2026 Masters and Doctoral Admissions

URBAN WATER CYCLE AND WATER TREATMENT TECHNOLOGIES

MSc Project

Synergistic hybrid system for enhanced removal of oils and suspended organics from industrial wastewater

Supervisor: Dr Tshepo J Malefetse (maleftj@unisa.ac.za)

Co-supervisors: Prof Thabo TI Nkambule; Dr. Luthando Tshwenya

This project proposes a hybrid water treatment system combining electrocoagulation with aluminium anodes and natural bio-polymers for improved removal of oils and suspended organics from industrial wastewater. The approach seeks to synergistically enhance floc formation, settling velocity, and process efficiency over conventional methods. The structured methodology involves reactor construction, standalone and hybrid process evaluation, optimization, and real effluent validation. Outcomes will be a greener and economically attractive treatment protocol, mechanistic insights, high-impact publications, and postgraduate skills development.

MSc Project

Smart water and artificial intelligence for drinking water treatment in Gauteng, South Africa

Supervisor: Prof Thabo TI Nkambule (nkambtt@unisa.ac.za)

Co-supervisors: Dr W. Moyo; Dr G. Mamba; Dr D. Ramutshatsha-Makhwedzha; Prof E. Mnkandla (CAIDS)

Gauteng, a province of over 15 million people, faces escalating water supply and quality pressures linked to infrastructure strain, catchment pollution, and high distribution losses. Conventional approaches are proving inadequate, creating risks of service interruptions and rising treatment costs. The project will incorporate smart monitoring and digital innovation to strengthen water governance. Real-time sensing, data analytics, and virtual modelling will guide faster decisions, improve operational efficiency, and engage communities through transparent information tools. The outcome of the project will include a rollout across major utilities aimed at enhancing compliance with national standards, reducing costs, building resilience to drought and contamination, and supporting Sustainable Development Goal.

PhD Project

Enhancing nutrient removal in wastewater treatment: comparative assessment of bacterial isolates from conventional processes

Supervisor: Dr Tshepo J Malefetse (maleftj@unisa.ac.za)

Co-supervisors: Prof S Mosebi; Rand Water Supervisor

This research project investigates the role and efficiency of nutrient-degrading bacteria isolated from conventional wastewater treatment plants, specifically focusing on enhancing ammonia, nitrate, and phosphate removal. By isolating and identifying bacterial strains from activated sludge and biotrickling filter systems at selected South African plants, the study aims to compare their nutrient removal efficiencies, both as single strains and in mixed cultures. Findings will inform optimization strategies for microbial-based treatment processes, potentially mitigating eutrophication risks in water bodies by improving nutrient management at wastewater facilities.

PhD Project

Recovery of nitrates and phosphates from wastewater using bacteria-immobilized systems

Supervisor: Dr Tshepo J Malefetse (maleftj@unisa.ac.za)

Co-supervisors: Dr Gcina Mamba; Prof Salerwe Mosebi

The research develops a biotechnological system using bacteria immobilized on natural mineral-based adsorbents for simultaneous phosphate and nitrate removal and recovery from wastewater. Using naturally occurring minerals as carriers, this eco-friendly strategy addresses nutrient pollution and promotes use of low-cost South African resources. This mitigates eutrophication risks and produces nutrient-enriched mineral matrices as slow-release biofertilizers, supporting the circular bioeconomy and sustainable agriculture.

PhD Project

Sustainable resource recovery from drinking water sludge in South Africa (Industry Project – uMngeni-uThukela Water)

Supervisor: Prof Thabo TI Nkambule (nkambtt@unisa.ac.za)

Co-supervisors: Dr TJ Malefetse; Dr Yadira B Fernandez (Cranfield University, UK)

This project focuses on the characterisation and management of by-products generated during drinking water purification, with particular attention to drinking water treatment sludge (DWTS) from South African facilities. Through detailed analysis of DWTS physical and chemical properties, including the fate and forms of heavy metals and the impacts of different treatment strategies, the study seeks to inform improved sludge management and resource recovery. The research integrates both chemical and biological methods for recovering valuable materials, striving to generate novel data that supports reduced environmental and health risks. By advancing sustainable approaches to residuals management and promoting circular economy principles, the project offers a valuable opportunity for researchers aiming to address emerging global challenges in water sustainability and responsible waste management.

MSc Project

Magnetic sustainable materials for the sorption and degradation of organic pollutants from wastewater and sludge matrices

Supervisor: Dr Tshepo J Malefetse (maleftj@unisa.ac.za)

Co-supervisors: Dr G Mamba; Dr D Ramutshatsha-Makhwedzha; Dr D Mogopodi (UB)

This project focuses on designing magnetically responsive, environmentally friendly materials for water remediation. Designed to adsorb and degrade persistent organic contaminants, the materials enable rapid separation, recovery, and potential reuse, reducing secondary pollution and operational costs. The project adopts a circular economy perspective, targets resource-efficient remediation, and evaluates performance under real wastewater conditions, supporting sustainable treatment and global water safety goals.

PhD Project

Development of a decentralized treatment regime for industrial wastewater towards non-potable reuse

Supervisor: Dr Gcina Mamba (mambag@unisa.ac.za)

Co-supervisors: Dr SC Tshangana; Dr ME Managa; Dr OT Mahlangu

Industrial wastewater treatment is essential towards ensuring that municipal wastewater treatment plants are not overburdened with highly concentrated and complex influent, which may ultimately compromise the overall effectiveness of the treatment. Also, the decentralized treatment systems could enable adequate treatment of the industry-specific wastewater to produce high quality effluent which may be recycled for non-potable uses within the same industry and other interested sectors such as agriculture. Therefore, this project seeks to explore the integration of various conventional tertiary wastewater treatment methods and with chemical oxidation for the treatment and disinfection of industrial wastewater such as brewery, dairy and abattoir wastewater. The treatment will target the removal of suspended particulates, dissolved organic matter including emerging pollutants and microbials. the aim is to produce high quality effluent which can be considered for re-use in non-potable applications.

MSc Project

Valorization of industrial wastewater treatment sludge for development of catalytic materials for degradation of pharmaceuticals in surface water

Supervisor: Dr Gcina Mamba (mambag@unisa.ac.za)

Co-supervisors: Dr L Tshwenya; Dr D Ramutshatsha-Makhwedzha

Sludge valorization is one of the most sustainable strategies towards reducing its potentially negative environmental impact. Therefore, this project will focus on exploring the beneficiation of wastewater treatment sludge from food industries such as abattoirs, brewery and dairy, to produce catalytic materials. These sustainable materials will be studied for their capability towards oxidative removal of emerging pollutants such as pharmaceuticals in surface water. This strategy provides a sustainable route for development of the catalytic materials through the conversion of waste to valuable materials.

PhD Project

Exploring the effectiveness of UV-mediated AOPs integrated processes for hospital wastewater treatment

Supervisor: Dr Gcina Mamba (mambag@unisa.ac.za)

Co-supervisor: Dr Tshepo J Malefetse; Dr W Moyo

Healthcare facilities are essential service providers responsible for the treatment of various ailments and injuries. In the course of their duty, hospitals generate wastewater that contains a cocktail of pharmaceuticals and microbial pollutants such as bacteria and viruses along with their drug-resistant strains and freestanding genetic material. These pollutants are elusive to conventional wastewater treatment systems. Therefore, this work will investigate the application of UV-driven advanced oxidation systems coupled with conventional treatment to target the treatment of hospital wastewater. UV systems of various wavelengths will be tested for their effectiveness when coupled with an oxidant for both degradation of pharmaceuticals and disinfection. This approach is expected to generate high quality effluent that can be discharged safely into the environment.

PhD Project

Wastewater treatment and resource recovery based on electrochemical anaerobic membrane bioreactor

Supervisor: Prof Thabo TI Nkambule (nkambtt@unisa.ac.za);

Co-supervisor: Prof MM Motsa; Dr Tshepo J Malefetse; Dr L Tshwenya

Anaerobic membrane bioreactor (AnMBR), one of the safest and least carbon-emitting wastewater treatment technologies, exhibits excellent application prospects in sustainable water treatment, resource recovery, and energy conversion in the post-COVID-19 and carbon-neutral era. However, severe membrane fouling is recognized as the main barrier to the widespread application of AnMBR. This project aims to establish a novel electrochemical AnMBR (eAnMBR) system, which can effectively mitigate membrane fouling by utilizing electrochemical reaction and micro-electric field. The microbial activity could be enhanced in the presence of micro-electric field, thus contributing to improved anaerobic digestion efficiency. Overall, this new eAnMBR technique is expected to simultaneously tackle three key aspects of the water-energy-food nexus: decentralized water treatment, water reuse, and nutrition recovery.

PhD Project

Assessment of water quality and nature-based solutions for the treatment of hypereutrophic water in South Africa

Supervisor: Prof Thabo TI Nkambule (nkambtt@unisa.ac.za)

Co-supervisors: Dr Gcina Mamba; Dr K Gajaje; Dr D Ramutshatsha-Makhwedzha

Untreated or inadequately treated municipal wastewater contributes to the alarming increase in eutrophic water systems across South Africa as evidenced by the rapid growth of invasive water plants such as water hyacinth and lettuce. This research will focus on the development of advanced water quality monitoring methods particularly for dissolved organic matter, emerging pollutants, antibiotic resistant bacteria and genetic material. In addition, the research will investigate the conversion of waste into useful materials for remediation of water pollution through catalytic, adsorptive and filtration approaches. Recovery of nutrients and other valuable chemicals from wastewater will also form part of this research.

PhD Project

Establishing a three-dimension correlation between natural organic matter and its heterogenous adsorption behaviour on activated carbon derived from different sources using EEM-PARAFAC

Supervisor: Prof Thabo TI Nkambule (nkambtt@unisa.ac.za)

Co-supervisors: Dr EM Managa; Dr W Moyo; Prof JM Madito

An effective and commonly used process when upgrading conventional water treatment plants for the removal of NOM and emerging micropollutants is adsorption (particularly activated carbon filtration). However, one disadvantage of using this method is that the recovery of powdered activated carbon (PAC) from the sludge is normally not easy. The use of Parallel Factor (PARAFAC) analysis in water treatment has the potential to simplify the complexity of unknown NOM fractions by identifying NOM components. The use of innovative low-cost and rapid online NOM fractions monitoring tools eliminates the use of traditional analytical instruments which may be cumbersome and costly. This study aim is to develop a custom-made powdered activated carbon and granular activated carbon filter for a specific water treatment plant based on an informed decision by EEM-PARAFAC.

MSc Project

Performance evaluation of low-cost waste-derived coagulants for sustainable inorganic contaminants removal from groundwater

Supervisor: Dr D Ramutshatsha-Makhwedzha (ramumd@unisa.ac.za)

Co-supervisors: Dr Tshepo J Malefetse; Dr TS Munonde

Groundwater supports South Africa’s urban water cycle by supplementing surface water during droughts and facilitating aquifer recharge through wastewater return. However, many South African groundwater sources contain high levels of inorganic pollutants such as fluoride, arsenic, and iron, posing health risks and limiting safe use. Conventional chemical coagulants for treatment are often too costly for large-scale application. This research will evaluate inexpensive coagulants derived from agricultural and industrial by-products to remove inorganic pollutants. By utilizing waste-derived treatment agents, the study supports circular economy principles, reduces costs, and promotes groundwater protection. Findings will demonstrate how treated groundwater can be more effectively integrated into urban water systems to strengthen water security and resilience in South African cities.

PhD Project

Integrating DAF and anoxic processes for optimization of nutrients removal and mitigating rising sludge in wastewater treatment plant

Supervisor: Prof Thabo TI Nkambule (nkambtt@unisa.ac.za)

Co-supervisors: Dr D Ramutshatsha-Makhwedzha; Prof AA Muleja

The research project aims to integrate Dissolved Air Flotation (DAF) and Anoxic processes for optimization of nutrients removal and to mitigate rising sludge in wastewater treatment plants. The project will investigate modular design to optimize efficiency for the removal of nutrients and assess how inadequate operating processes management leads to rising sludge that negatively affects wastewater treatment performance. This will address operational problems that contribute to an increase of sludge in the secondary clarifier and below standard discharge effluent. The research will evaluate three process optimization methods which include hydraulic system modifications and aeration management and sludge handling techniques to boost nutrients elimination while preventing sludge bulking and flotation problems. The research will leverage implementation of process engineering principles in wastewater treatment practices to develop sustainable solutions which enhance treatment plant efficiency while meeting effluent discharge requirements and promoting environmentally friendly water management systems.

MSc Project

Mechanistic and scalable breakthrough studies using fixed-bed columns for organic pollutant removal from wastewater

Supervisor: Dr D Ramutshatsha-Makhwedzha (ramumd@unisa.ac.za)

Co-supervisors: Dr Gcina Mamba; Dr W Moyo

This research project will investigate fixed-bed adsorption column technology for organic pollutant removal from wastewater through breakthrough studies. The conventional wastewater treatment plants fail to remove trace organic contaminants which include pharmaceuticals and pesticides and industrial solvents thus posing danger for human health and environmental systems. The research will perform continuous-flow fixed-bed column tests with waste materials as adsorbents. The breakthrough capacity, performance indicators and pollutant removal mechanisms will be assessed through breakthrough curve analysis. The research will study how different operational factors affect the process. The modelling and mechanistic evaluation will help develop methods to increase scaling up of the process for implementation in actual wastewater treatment plants. The research will develop an efficient sustainable method to remove organic pollutants from wastewater which will enhance water quality and protect public health.

ANALYTICAL AND ENVIRONMENTAL RESEARCH THEMATIC AREA

MSc Project (NRF Thuthuka funded project)

Microwave digestion and sequential extraction of selected metals and phosphorus from municipal wastewater sludge using green solvents

Supervisor: Dr TS Munonde (munonts@unisa.ac.za)

Co-supervisor: Dr N Magwaza

Implementation of newly effective methods for phosphorus and ammonium recovery from wastewater sludge is critical to advance sustainable fertilizer production. However, municipal sewage sludge consists of various inorganic and organic pollutants, with most organic pollutants dealt with during microwave digestion. However, the concentrations of metals and phosphorus during digestion remain the same. This allows for the sequential extraction of metals with phosphorus recovery from sewage sludge ash through an easily soluble form. Based on the observations from the literature, it appears that there is potential to use microwave digestion as an effective means to recover and reuse both the metals and the valuable phosphorus present in sewage sludges. This work aims to find a method for creating easily soluble and recoverable forms of metals whilst recovering phosphorus, with the potential of being used as a fertilizer.

MSc Project

Integrated process optimization and mathematical modelling towards the adsorptive recovery of ammonium and phosphates in wastewater

Supervisor: Dr TS Munonde (munonts@unisa.ac.za)

Co-supervisors: Dr MP Mubiayi; Dr D Ramutshatsha-Makhwedzha

Integrated processes that combine adsorption with mathematical modelling can be used for recovering ammonium and phosphate from wastewater, often with optimized conditions. The integrated approach improves the ability of adsorbents to capture ammonium and phosphates efficiently for use as slow fertilizers, aligning with the circular economy. Thus, in addition to studying the adsorption of ammonium and phosphates, mathematical models such as Response Surface Methodology (RSM) and Artificial Neural Networks are employed to identify the most effective operating conditions for the adsorption process, whilst predicting the optimal operating conditions. This work aims to develop an adsorption method for recovering ammonium and phosphate from wastewater, combined with models that will help predict how changes in process parameters will affect nutrient removal, allowing for efficient control and optimization of the method.

MSc Project (NRF Thuthuka funded project)

Layered double hydroxide/carbon nanocomposite for the optimized adsorptive recovery of ammonium and phosphates from municipal wastewater

Supervisor: Dr TS Munonde (munonts@unisa.ac.za)

Co-supervisor: Prof L De Kock

Nutrient recovery from wastewater is a sustainable approach to wastewater management, particularly with the end goal resulting in their transformation into high-performing fertilizers, which helps in closing the loop for resource utilization. The adsorption and recycling of nutrients (ammonium and phosphates) will be done in this study in an effort to design a low-cost technology that can be used for routine recovery of phosphates. The HPLC and UV will be used for the detection and quantification of the targeted nutrients, alongside other detected contaminants from wastewater. Multivariate analysis will be used to come up with optimum conditions for the effective adsorption of ammonia nitrogen (AN) and phosphorus (P) in wastewater. The main goal of this work is to develop adsorption technology that can be used for the recovery of ammonium and phosphates using advanced Layered double hydroxide composites and the feasibility of using the recovered nutrients as fertilizers.

MSc Project

Assessment of antioxidant activity, chemical contaminants, and metabolic pathways in surface water using liquid and gas chromatography techniques

Supervisor: Dr N Magwaza (magwan@unisa.ac.za)

Co-supervisors: Dr TS Munonde; Prof LM Madikizela

This study aims to evaluate antioxidant activity, chemical contaminants, and metabolic pathways in surface water samples. Surface water is a vital resource that is increasingly impacted by natural and anthropogenic pollutants, which may pose risks to environmental and human health. Chemical contaminants will be identified and quantified using Liquid Chromatography (LC) and Gas Chromatography (GC) techniques, providing accurate analysis of both polar and non-polar compounds. The metabolic pathways of these contaminants will be investigated to understand their transformation and persistence in the aquatic environment. Additionally, the antioxidant potential of the water samples will be assessed to identify bioactive compounds that may counteract oxidative stress. The findings will contribute to a better understanding of water quality, pollutant behaviour, and potential protective properties, supporting informed water management and environmental monitoring strategies.

MSc Project

Heavy metals in marine organisms: A source apportionment

Supervisor: Prof LM Madikizela (madiklm@unisa.ac.za)

Co-supervisors: Prof N Mketo; Dr TS Munonde

The discharge of heavy metals into the open oceans through the contaminated estuarine water is an environmental concern. Several studies have reported the occurrence of heavy metals in the coastal environments. Hence, the proposed study will monitor the occurrence of such metals in the marine environment which include selected organisms, while also tracing their sources. Analytically, heavy metals will be monitored with inductively coupled plasma after microwave digestion. Finally, the distribution of these contaminants in coastal environments and various organs of the fish will be evaluated.

PhD Project

Development of water hyacinth-based material for solid-phase extraction and removal of selected personal care products in water

Supervisor: Prof LM Madikizela (madiklm@unisa.ac.za)

Co-supervisors: Prof VE Pakade; Dr Gcina Mamba

The contamination of South African water resources with personal care products has become a public knowledge. Hence, this study aims to monitor the quantities of these contaminants and their removal in South African waters. Environmental monitoring for personal care products will be performed with solid-phase extraction-liquid chromatography. This will be followed by the developments of agricultural waste-based adsorbents for remediation. A wide range of state-of-the-art, top-of-the-range, analytical tools are available for characterization.

PhD Project

Tracing of environmental pollutants in marine organisms: A case of selected pharmaceuticals in fish

Supervisor: Prof LM Madikizela (madiklm@unisa.ac.za)

Co-supervisors: Prof TAM Msagati; Prof N Mketo

The discharge of pharmaceuticals into the open oceans through the contaminated estuarine water is an environmental concern. Several studies have reported the occurrence of various pharmaceuticals belonging to therapeutic classes of antibiotics, antiretroviral drugs and non-steroidal inflammatory drugs in South African coastal environments. Hence, the proposed study will monitor the occurrence of these drugs in the marine environment which include selected organisms. Analytical methods for pharmaceutical analysis will comprise of solvent extraction followed by preconcentration with solid-phase extraction and finally chromatographic quantitation on LC-MS. Finally, the distribution of these contaminants in coastal environments and various organs of the fish will be evaluated.

PhD Project

Synthesis of molecularly imprinted polymer for selective extraction of sildenafil in aqueous phase

Supervisor: Prof LM Madikizela (madiklm@unisa.ac.za)

Co-supervisor: Prof L De Kock

The project will involve the synthesis and full characterization of a selective molecularly imprinted polymer prior to its application.

MSc Project

Assessment of natural biopolymers in the removal of turbidity and heavy metals from wastewater treatment plants

Supervisor: Dr TS Munonde (munonts@unisa.ac.za)

Co-supervisors: Dr Ngandjui Tchangoue, Yvan Anderson; Dr Gcina Mamba

Access to safe water remains a challenge in South Africa, particularly in rural communities exposed to contaminated surface waters. Conventional coagulants like alum are effective but raise concerns over cost, residual aluminum, and health risks. Natural biopolymers offer biodegradable, eco-friendly alternatives with promising coagulation and flocculation properties.

This project will compare the performance of biopolymers and alum in removing turbidity and heavy metals from local surface waters using laboratory jar tests. Key parameters (pH, turbidity, metal concentration, and settling time) will be analysed to determine optimal dosages and removal efficiencies. Findings aim to promote sustainable, low-cost water treatment options that support South Africa’s pursuit of safe water access and Sustainable Development Goal 6.

MSc Project

Investigating multi-process phyto-electrocoagulation treatment for quality improvement of water in mining sites

Supervisor Dr TS Munonde (munonts@unisa.ac.za)s

Co-supervisors: Dr AO Adeeyo; Dr Tshepo J Malefetse

Water resources impacted by mining activities have been reported to contain antimicrobial-resistant microbes and various forms of metal pollutants. This project aims to investigate novel phyto-coupled electrocoagulation process in the treatment of mine-impacted water. Artificial intelligence-based tools will be employed to identify key variables for optimizing the process. The research will integrate microbiological studies with the green synthesis of phytometabolites, alongside the application of process optimization tools to strengthen scientific outcomes.

INDUSTRY PROJECTS

PhD Project

Early Warning Model Development for Cyanobacterial Bloom Forecasting

Supervisor: Dr Tshepo J Malefetse (maleftj@unisa.ac.za)

Co-supervisors: Prof Thabo TI Nkambule; Prof LM Madikizela; Dr Annelie Swanepoel (Rand Water)

This research aims to enhance the management of strategically important reservoirs by developing innovative forecasting tools for cyanobacterial blooms in Southern African water systems. The project will focus on integrating real-time monitoring technologies and advanced modelling approaches to predict the proliferation of select algal species under varying environmental conditions. By coupling online water quality data with robust modelling systems, this work seeks to support early warning capabilities for water managers and treatment facilities. The anticipated outcomes include improved predictive capacity for harmful algal events and insights that can optimize water treatment and safeguard water supply reliability.

MSc Project

Mitigating water quality risks in hypereutrophic dams in South Africa: Evaluation of alternative coagulants and functionalized adsorbents

Supervisor: Prof Thabo TI Nkambule (nkabutt@unisa.ac.za)

Co-supervisors: Dr W. Moyo; Dr Gcina Mamba; Dr D. Ramutshatsha-Makhwedzha

Eutrophication in surface waters, driven by nutrient enrichment and persistent algal blooms, poses major challenges for drinking water treatment. High dissolved organic matter (DOM) levels reduce efficiency, increase costs, and heighten risks of cyanotoxins, taste and odour isssues, and disinfection by-product (DBP) formation. Conventional coagulants such as alum and ferric chloride, though widely applied, often require high doses, generate large sludge volumes, and show limited effectiveness against low-molecular weight organics and toxins. The study will investigate hybrid and alternative approaches, including waste-derived coagulants, bio-based polymers, and engineered adsorbents. By integrating water characterization, treatment performance, and optimization, the project aims to deliver sustainable, cost-effective solutions.

PhD Project

Treatment of Saline Waters with Freeze Crystallization

Supervisor: Prof Johannes Maree (mareejp@unisa.ac.za)

Co-supervisors: Prof MA Kebede; Dr Tshepo J Malefetse

This project focuses on advanced water treatment and resource recovery, specifically using Pipe Freeze Crystallization (PFC) for managing saline industrial effluents such as mining-influenced waters, hazardous leachates, and desalination brines. Traditional brine management methods like evaporation ponds and dams present environmental risks and high costs, whereas freeze crystallization offers a sustainable approach by generating clean water and valuable salts, supporting zero-waste discharge objectives. The research will involve optimizing PFC technology through enhanced heat exchanger design, selective salt recovery strategies, product quality assessments, and techno-economic feasibility studies. The project aims to develop a scalable and commercially viable freeze crystallization process, producing high-impact publications, technology demonstrations, and practical industry guidelines.

NANOSTRUCTURED MATERIALS

MSc Project

Inactivation of bacterial contaminants in water with solar energy driven expanded porphyrins combined with green synthesized nanoparticles

Supervisor: Dr ME Managa (managme@unisa.ac.za)

Co-Supervisor: Prof Thabo TI Nkambule

Pathogenic microorganisms continue to excel in causing infectious diseases through the transfer of antibiotic resistance genes. Porphyrins and porphyrin-like compounds are one of the most studied second-generation photosensitizers in antimicrobial photodynamic inactivation (aPDI). Expanded porphyrins are now emerging as a promising class of molecules for application as photosensitizers. Due to their facile synthetic modifications, a number of expanded porphyrins have been prepared either by insertion of metals, connecting the pyrrole rings, changing the substituents, and replacing the pyrrole rings with thiophene or furan rings. These properties can be enhanced by conjugation of nanoparticles that are synthesised using green chemistry which then mitigate environmental pollution which in turn address environmental issues. The interaction between nanoparticles and the Porphyrins and porphyrin-like compounds is expected to improved singlet oxygen generation when excited with light. Singlet oxygen is the predominant cytotoxic substrate amongst all the reactive oxygen species (ROS). The ROS interacts with various bacterial cell components such as proteins and the deoxyribonucleic acid (DNA) bases. There are various mechanisms through which bacterial inactivation occurs because of these ROS.

MSc Project

Use of low-density polyethylene reinforced with hyacinth-derived biochar for the removal of phosphate and nitrates from wastewater

Supervisor: Dr TN Moja (mojatn@unisa.ac.za)

Co-supervisors: Prof ZN Cabunda and Dr TS Munonde

Nitrates (NO^3-) and Phosphates (PO₄^3-) are essential nutrients but contaminants when their concentration are too high in water bodies. High concentrations of NO^3- and PO₄^3- can cause eutrophication and algae-like bacteria in water that can eventually cause rapid plant growth and reduce water quality. These elevated nutrients are usually caused by agricultural runoff, such as fertilizers utilized in major farming, household products, and industrial waste discharge. To address the stated accumulation of   NO^3- and PO₄^3- in water bodies, the use of an adsorbent derived from water hyacinth and polyethylene biopolymer composite will be applied for the remediation of  NO^3- and PO₄^3- in dams, rivers, and wastewater. Characterization techniques such as ion chromatography and colorimetric techniques will be used to determine the concentration level of  NO^3- and PO₄^3-, and TEM, SEM-EDS, FTIR, and XRD will be utilized for surface morphology.

MSc Project

Fabrication of a sustainable water filtration system for the removal of microbial and heavy metal pollution in surface water

Supervisor: Dr MP Mubiayi (emubiamp@unisa.ac.za)

Co-supervisors: Dr G Mamba and Prof ZN Cabunda

The quality and access to freshwater around the world is deteriorating due to numerous factors, including climate change and pollution from various domestic and industrial activities. To achieve Sustainable Development Goal 6 (SDG 6), it is crucial to develop sustainable and accessible water treatment systems to address the significant drinking water challenges faced by numerous communities on a daily basis. This project focuses on the design and fabrication of a facile, simple point-of-use filtration system using natural and sustainable materials for the removal of microbial contaminants and heavy metals in surface waters. To ensure improved water quality and longevity of the filtration system, it will be coupled with a pre-treatment step to reduce the pollutant loading. The water filtration system is anticipated to provide better quality water, especially to communities using untreated, polluted surface water daily.

MSc Project

Fabrication of porous multilayered clay-based ceramic membrane for the removal of heavy metals in aqueous solution

Supervisor: Dr MP Mubiayi (emubiamp@unisa.ac.za)

Co-supervisors: Dr TN Moja and Prof MM Motsa

The pollution of drinking water by heavy metals results in a detrimental effect on living organisms. It is recommended that comprehensive water management strategies are crucial for addressing the water challenges faced in certain regions. This can be achieved by implementing technological innovations for the facile and cost-effective removal of pollutants in water and wastewater. The reuse of waste from various sectors, including agriculture, will have a positive impact on the reduction of secondary pollution from some of those wastes. The waste-to-wealth concept will provide solutions to reduce its detrimental effect on the environment.  This project will focus on the fabrication of a multilayered clay-based porous ceramic membrane for the removal of heavy metals such as zinc, arsenic, and lead in aqueous solutions. Waste materials from the agriculture sector will be used, and an investigation into the formation of pores will be carried out. The optimum ceramic membrane exhibiting the best properties will be proposed for further study, such as being used in an integrated water treatment system targeting numerous pollutants.

MSc Project

Nanobubble ozonation for removal of contaminants of emerging concern (CECs) in water

Supervisor: Prof AT Kuvarega (kuvarat@unisa.ac.za)

Co-supervisors: Prof ZN Cabunda and Dr ME Managa

This project entails the use of UV or visible light photons to activate ozone nanobubbles for enhanced degradation of CEC such as pharmaceuticals and personal care products. The study evaluates the in-situ activation of ozone to form reactive radicals from ozone nanobubbles generated from a nanobubble generator. The effect of oxidants such peroxydisulfate (S₂O₈²), and/or use of high energy UV photons, solar light, or ultrasound energy or a combination of these on the efficacy of the removal of the target pollutants will be evaluated. Techniques such as UV-Vis, LC-MS, TOC and EPR will be used to assess the merits of the optimized parameters of the study.

MSc Project

 Carbon sphere-supported semiconductor heterojunctions for photocatalytic degradation of organic dye pollutants in water

Supervisor: Prof ZN Cabunda (tetanzn@unisa.ac.za)

Co-supervisors: Prof AT Kuvarega and Dr ME Managa

This project focuses on the fabrication of carbon sphere-supported semiconductor heterojunction photocatalysts for the degradation of organic dye pollutants in water. The unique combination of water wettability and dye adsorption capabilities in these composites is expected to enhance the photocatalytic process compared to single-component photocatalysts. The large surface area of carbon spheres offers abundant active sites for catalytic reactions, while their excellent electrical conductivity facilitates efficient charge transfer between the heterojunction photocatalysts and the target dyes. This synergy leads to improved photocatalytic performance by promoting effective separation of photo-generated electron-hole pairs within the heterojunction. The enhanced photocatalytic activity of the proposed nanocomposites arises from the combined effects of the large surface area and superior electrical conductivity of the carbon spheres, which together boost the overall degradation efficiency of organic dyes in water.

PhD Project

Catalytic ozonation on glass beads supported g-C₃N₄/BiVO₄ visible light active photocatalysts for the removal of fluoroquinolones in water

Supervisor: Prof AT Kuvarega (kuvarat@unisa.ac.za)

Co-supervisors: Prof D Liu, Prof BB Mamba and Dr PM Mubiayi

This project involves the use of an integrated ultrasonication-nanobubble ozonation system for solar light degradation of selected fluoroquinolones (ciprofloxacin and levofloxacin) in a reactor with submerged glass supported Z-scheme photocatalysts (g-C₃N₄/BiVO₄). The sonicator will be used to sonicate solutions of the Z-scheme photocatalysts supported on a flat glass surface while bubbling ozone through the reactor system. The Z-scheme photocatalysts will be synthesised through a hydrothermal method and characterised. The photocatalyst will then be supported on a piece of glass through a simple spraying technique. The study on the synergist effect of ultrasonication-ozonolysis of the supported g-C₃N₄/BiVO₄ on the degradation of the fluoroquinolones under visible light irradiation will then be carried out.

PhD Project

Metal-Organic Framework-derived carbon-based photocatalysts for the degradation of organic contaminants in aqueous systems

Supervisor: Prof ZN Cabunda (tetanzn@unisa.ac.za)

Co-supervisors: Dr TN Moja, Dr PM Mubiayi and Prof U Feleni

In this project, visible-light-active semiconductor/MOF/carbon-based nanocomposites will be fabricated for the photocatalytic degradation of organic dye pollutants in water. Doping MOFs with active agents is highly desirable, as it can significantly enhance photocatalytic efficiency compared to the bare frameworks. The materials used in this study include a class of MOFs known as zeolitic imidazolate frameworks (ZIFs), carbon nanomaterials, and semiconductor materials. These semiconductor/MOF/carbon nanocomposites are characterized by high porosity, good thermal and chemical stability, ease of functionalization, strong adsorption capacity, elevated photocatalytic activity, and a high surface area-to-volume ratio compared to the parent MOF. The composite materials will be thoroughly characterized using various analytical techniques and then evaluated for their effectiveness in the photodegradation of organic dye pollutants in water.

MEMBRANE SCIENCE AND TECHNOLOGY

MSc Project

Membrane filtration and influence of peracetic acid coupled with AOP in the degradation of contaminants of emerging concern in water

Supervisor: Dr SC Tshangana (tshansc@unisa.ac.za)

Co-supervisors: Prof AA Muleja, Dr L Nthunya and Prof Thabo TI Nkambule

Membrane filtration is applied in the water industry for potable or wastewater treatment purposes. It is a non-destructive technology where substances smaller than the membrane pore sizes filter as the permeate. Peracetic acid (PAA) is known as a strong disinfectant used in water treatment. Advanced oxidation process (AOP) is a destructive technology where complex compounds can be mineralized into simpler molecules. AOP can generate various radical species with the ability to discriminately attack other molecules in the same medium. In this work, the influence of PAA and superoxide radicals in the destruction of contaminants of emerging concern (short chain PFAS and pharmaceuticals) will be investigated to elucidate the mechanism of removal. Various materials (i.e. graphene oxide quantum dots, biochar and natural zeolite) and energy sources (i.e. UV/Vis) will be studied to achieve this objective. The AOP unit will be assisted by membrane filtration with the aim to ensure efficiency of removing potential by-products (i.e. disinfection by-products) and other undesirable residuals in water for drinking purpose. To shed some light on the treated water, the hybrid system will be tested for integration before disinfection stage in a water treatment plant.

MSc Project

Low pressure-high integrity membrane for removal of pathogens

Main supervisor: Dr NN Madzivha (gumbinn@unisa.ac.za)

Co-supervisors: Prof AA Muleja, Prof MM Motsa, Dr FH Mudau

When membrane integrity is compromised, pathogens and other unwanted substances can easily pass through the membrane and contaminate the product water. The study proposes the development of low-pressure, but high integrity membranes for pretreatment purposes, particularly for the removal of pathogens in contaminated water through structure control and the infusion of various carbon-based nanomaterials in the membrane matrix.

MSc Project

Assessing the integration of membrane, foam fractionation and destructive technologies for effective removal of PFAS in water treatment plants

Supervisor: Prof AA Muleja (mulejaa@unisa.ac.za)

Co-supervisors: Dr NN Madzivha, Prof MM Motsa, Prof Thabo T.I Nkambule

Per- and polyfluoroalkyl substances (PFAS) are manufactured chemicals known as “forever chemicals” with extensive applications in everyday products. Such applications result in their widespread presence in the environment/water. There is identified associations between PFAS exposure, and several health impacts i.e. increases in cholesterol levels, pregnancy-induced hypertension and preeclampsia. These chemicals have also been found in drinking water treatment facilities in Southern African countries including Namibia and South Africa. It is therefore imperative to remove PFAS from water due to their reported health effects. The principal objective this project is to assess the integration of modular units of membrane (i.e. ultrafiltration, nanofiltration or reactive electrochemical membrane), foam fractionation and destructive technologies (i.e. electrochemical oxidation or photocatalytic oxidation) for efficient removal of PFAS in a continuous mode for implementation in water treatment plants. Recently it has been reported that “investing in PFAS removal is not just about compliance; it is about protecting public health and preserving our most vital resource of clean water. As we continue to innovate and adapt, it is important to ensure that the solutions we deploy are not only effective but also equitable and sustainable”. The outcome of this project aims to contribute significantly towards achieving these goals.

PhD Project

Charged Hollow-fibre Nanofiltration membrane for efficient organic removal in landfill leachate/wastewater effluent

Supervisor: Prof MM Motsa (motsamm@unisa.ac.za)

Co-supervisors: Dr NN Madzivha, Prof AA Muleja

Nanofiltration (NF) is the intermediate mark between ultrafiltration and reverse osmosis. By definition nanofiltration is capable of high removal of divalent metal ions, anions with poor retention of monovalent ions. It also has efficient removal of dissolved organics (organic compounds). Pre-treated landfill leachate and municipal wastewater effluent is often dominated by low molecular weight organics, metal species and nutrients. As such part of this project seeks to build-up on previous research developments on ultrafiltration hollow-fibre membranes to prepare chemically stable nanofiltration hollow fibres in a single-step for fit-for-purpose treatment of wastewater effluent and pre-treated landfill leachate. The work will extend to membrane module design, evaluation and in-place cleaning processes. Benchmarking will also be conducted using commercially available nanofiltration membrane variants.

PhD Project

Development of a Hybrid Photocatalytic-NF Desalination System for Brackish Water Treatment

Supervisor: Prof EN Nxumalo (nxumaen@unisa.ac.za)

Co-supervisors: Dr NN Madzivha, Prof BB Mamba and Prof L Shao

This project pioneering research project develops a photocatalytic-NF desalination membrane device. Existing membrane systems in the potable water treatment industry are typically ultrafiltration, thereby are incapable of removing the metallic salts from either seawater or salty brackish water systems. As such a nanofiltration membrane device for desalination of brackish water will be utilised in this project. Nanofiltration membranes by themselves are prone to pore clogging by organic pollutants, the strategy of fouling mitigation through photocatalytic enhancement will be investigated in our system and the NF membranes will be embedded with photocatalytic nanomaterials to abate fouling so as to enhance the longevity of the salt rejection.

PhD Project

Assessment of effectiveness of integrating pretreatment protocol with zwitterionic membranes for enhanced solute rejection and high reusability potential in complex wastewater treatment

Supervisor: Prof RM Moutloali (moutlrm@unisa.ac.za) 

Co-supervisors: Prof MM Motsa and Dr F Matebese

Over the years, multiple reports of water contamination through sewage discharge and ingress in places like the Vaal catchment, Hammanskraal in Tshwane, Makhanda in the Eastern Cape, and many more areas is well published. This is further aggravated by underperforming wastewater treatment plants (WWTPs) which contributes to the contamination of rivers downstream. The integration of membrane technology into the current WWTP treatment chain is considered one of the solutions for this challenge. Membrane systems, however, are currently undermined by their propensity to foul under complex wastewater streams. In this project, membranes will be integrated with chemical coagulation/flocculation treatment processes prior to membrane filtration. On the other hand, the surfaces of the membranes will be modified with stimuli-responsive zwitterionic grafts to mitigate against solute deposition and attachment onto the membrane surfaces. The combination of chemical treatment and stimuli-responsive zwitterionic membranes is expected to lead to predictable solute-membrane surface interactions which will lead to better membrane design for solute selectivity and fouling mitigation. Several environmental changes and factors will be explored to activate the surface grafts to induce the required activation due to the wide range of emerging solutes in complex wastewater feed. The project seeks to develop a process framework towards effective pretreatment choices and integration with membrane filtration based on the complexity of the feed wastewater.

APPLIED ELECTROCHEMISTRY

MSc Project

Enhanced desalination performance of capacitive deionization based on novel graphene-manganese oxide nanocomposite electrocatalyst as the effective electrode in water purification

Supervisor: Dr NW Hlongwa (hlongnw@unisa.ac.za)

Co- supervisors: Prof MM Motsa and Dr SE Sekhosana

Capacitive Deionization (CDI) method for water purification shares the same ion storage mechanism as a supercapacitor. This is cutting-edge technology, suitable for low to medium ion concentration water purification. This technology works by desalinated ions driven to and then absorbed on oppositely charged electrodes under low voltage (≤ 2 V). Unlike reverse osmosis and thermal-based distillations, ions are absorbed directly from the water body instead of taking water molecules out during the charge step, which could save lots of energy, during the discharge. The stored ions will be released, electrodes will be regenerated, and partial energy could be recovered, the same as a supercapacitor. The key component in achieving the whole adsorption and desorption process is the electrodes. Many forms of carbon have been utilized for CDI electrodes. The research will involve the synthesis and characterization of novel nanostructured materials to be used as electrodes in the study of water purification. The objectives of this research are to desalinate seawater, and we will begin to use common salt (NaCl, KCl) in the lab to test the CDI device constructed.

MSc Project

Ruthenium-Doped MoS₂ Nanoflowers Supported on Graphitic Carbon Nitride for Electrochemical Sensing of Ronidazole in Water

Supervisor: Dr KE Sekhosana (sekhoke@unisa.ac.za)

Co-supervisors: Dr Nobuhle Ndebele and Prof Mesfin Kebede

Various infections that proliferate in hypoxic conditions are normally combatted with a class of imidazole ring-based drugs known as nitroimidazoles. This class of drugs includes metronidazole, tinidazole, ronidazole and nimorazole all of which exhibit antiparasitic, antibacterial, and anticoccidial effects. Ronidazole, being a veterinary drug, is applied in the treatment of coccidiosis and histomoniasis in poultry, swine dysentery in pigs, bovine trichomoniasis in cattle, parasitic infections in farmed fish, human bacterial and protozoal infections. Ronidazole may be carcinogenic, genotoxic, and mutagenic and can pose a scare to the natural balance of ecosystems due to its low biodegradability and high-water solubility. It is, thus, very much considerable that highly sensitive tools for establishing ronidazole in water bodies and other environments be developed. In this study, functionalized molybdenum sulfide doped with ruthenium ions and clicked to phthalocyaninato chelates will be developed, with nanocomposite used in the fabrication of an electrochemical sensor on the platform of glassy carbon electrode with graphitic carbon nitride sheets. 

MSc Project

Development of Self-powered water desalination device using Aluminium-air (Al-air) as electrochemical desalination system

Main supervisor: Prof MA Kebede (Mesfiak@unisa.ac.za )

Co-supervisors: Prof X Fuku and Dr NW Hlongwa

The project intends to develop a self-powered water desalination device using metal-air (Al-air) battery with the capability of simultaneous generation of electricity. The project targets to develop optimized devices to decrease the salinity of saltwater by reasonable percent with promising energy generation in operation hours. Metal-Air Desalination Battery such as Al-air desalination battery system will be fabricated which will be concurrently function as a desalination system and a power source. The desalination battery will be fabricated using the carbon felt as the cathode and aluminum/zinc sheet as the anode.

MSc Project

Wastewater Treatment Sludge-Derived Electrochemically Exfoliated Graphene–Based Composites for Hybrid Supercapacitors

Supervisor: Prof. M.J Madito (maditmj@unisa.ac.za)

Co-supervisors: Dr N.W Hlongwa, Prof M. Kebede and Dr Mojeed Olailekan Bello

This project explores the sustainable transformation of wastewater treatment sludge into high-value materials. The study focuses on converting sludge into activated carbon and subsequently into electrochemically exfoliated graphene (EEG). This approach not only offers an innovative pathway for sludge valorization but also addresses critical challenges in wastewater sludge management, water contamination control, and the protection of aquatic ecosystems. By integrating resource recovery with advanced material synthesis, the project contributes to the preservation of water quality and long-term sustainability. Importantly, the development of EEG from sludge-derived activated carbon remains largely unexplored, opening opportunities for novel applications in high-performance hybrid supercapacitors

MSc Project

Dual-Mode Colorimetric-Electrochemical Sensors for Rapid Detection of Hazardous Chemicals in Water Systems

Supervisors: Prof X Fuku (fukuxg@unisa.ac.za)

Co-supervisors: Prof Usisipho Feleni, Dr Nobuhle Ndebele and Dr Kutloano Sekhosana

Water contamination by hazardous chemicals such as heavy metals, pesticides, and industrial pollutants poses serious risks to human health and the environment. Conventional detection methods are often time-consuming, expensive, and require sophisticated laboratory infrastructure, which limits their application for on-site and real-time monitoring. There is a critical need for rapid, sensitive, and cost-effective sensing technologies that can provide accurate detection of hazardous substances in diverse water systems to support water safety, environmental protection, and public health.

MSc Project

Waste-derived catalysts for wastewater splitting

Supervisors: Prof X Fuku (fukuxg@unisa.ac.za)

Co-supervisors: Dr K Sekhosana, Prof Mesfin Kebede and Dr TS Munonde

Hydrogen production through water electrolysis remains constrained by high costs, intensive energy requirements, and the need for stable, efficient catalysts. Conventional electrocatalysts often rely on scarce and expensive noble metals, which limit their scalability and sustainability. At the same time, the increasing generation of wastewater and solid waste presents environmental management challenges, while their potential as alternative resources for clean energy production remains underexplored. The lack of cost-effective, sustainable catalytic systems for wastewater splitting represents a significant barrier to advancing large-scale hydrogen production and addressing both energy and environmental concerns.

MSc Project

Hybrid Gel-Electrolyte Membrane-Free Electrolyzers for Sustainable Hydrogen Production Using E-Waste-Derived Catalysts and Mixed Wastewater Feeds

Supervisors: Prof X Fuku (fukuxg@unisa.ac.za)

Co-supervisors: Prof Moshawe Madito and Dr Idris Mustapha

This project aims to develop a new generation of membrane-free electrolyzers that utilize polymer/agar-based gel electrolytes for safe and efficient hydrogen production. The system integrates catalysts synthesized from e-waste metals with mixed wastewater streams as the electrolyte feed. This dual approach not only addresses the global e-waste crisis but also contributes to wastewater valorization and green hydrogen generation.

MSc Project

Electrochemical biosensor system for monitoring anti-depressants in wastewater detection

Supervision team: Prof Usisipho Feleni (felenu@unisa.ac.za)

Co-supervisors: Dr Valentine Saasa and Dr Simphiwe Zwane

The rise in mental health disorders has resulted in antidepressants (ATDs) and their metabolites detection in wastewater treatment (WWTP) plant influent and effluent at concentrations ranging from 72.62 – 5011.8 ng.L^-1 and 114.48 – 6992.40 ng.L^-1, respectively. The increase in their concentrations in the effluent suggests a negative removal of the micropollutants, indicating the resistance of the drugs to conventional WWTP technologies and may be forming ATDs-conjugates during biological treatment. ATDs are emerging environmental micropollutants that need to be monitored and removed from wastewater to minimize their risks to human health and the aquatic environment. This study proposes the use of thiolated aptamer combined with hexagonal boron nitride and molybdenum disulfide (MoS₂) nanoparticles as electrode material for monitoring fluoxetine (FLX) and citalopram (CIT) in wastewater.

MSc Project

Electroanalytical monitoring of fluoroquinolones in wastewater

Supervisor: Prof Usisipho Feleni

Co-supervisors: Dr TS Munonde and Prof Thabo TI Nkambule

Water quality monitoring requires new water electroanalytical systems with highly sensitive and low-power consumption to detect pollutants. This involves the use of electrochemistry and analytical techniques to monitor fluoroquinolones in water. The electrochemical system development will employ a composite material focusing on lanthanide-based nanocomposite as a platform. On the other hand, the analytical tools will be employed for validation.

PhD Project

Flexible and Portable Dual-Sensor Devices for Remote Water Monitoring and Green Hydrogen Generation

Supervisors: Prof X Fuku (fukuxg@unisa.ac.za)

Co-supervisors: Dr Idris Mustapha, Prof Mxolisi Motsa and Dr Ntuthuko Hlongwa

Access to clean water remains a major global challenge, particularly in remote or resource-limited areas where heavy metal contamination (e.g., Pb, As, Cd, Hg) threatens human health. Conventional monitoring requires laboratory-based analysis, which is costly and inaccessible in the field. At the same time, there is a pressing need for decentralized renewable energy solutions. A flexible, portable device that combines real-time water monitoring with green hydrogen production could address both challenges simultaneously.

PhD Project

Spectroelectrochemical reactor for the detection of Influenza antibiotics in water bodies

Supervisor: Prof Usisipho Feleni (felenu@unisa.ac.za)

Co-supervisors: Prof Xolile Fuku, Prof Bhekie B. Mamba and Dr Simphiwe Zwane

Antiviral drugs (ATVs) are pharmaceuticals that are widely used to treat illnesses caused by viruses us such as infuenza. Particularly, ATVs were consumed in such large quantities during the pandemic that high concentrations are detected in wastewater and aquatic environment. There has been rising research on the behavior of ATVs in the environment has surged since the pandemic. Therefore, a comprehensive assessment of the occurrence, removal, and risk of ATVs is urgently needed. This project is focused on the development of an electrochemiluminescence (ECL) reactor for monitoring Oseltamivir and zamanivir in water bodies.

PhD Project

Optimization and validation of electrochemical system for antiretroviral drugs in water

Supervisors: Prof Usisipho Feleni (felenu@unisa.ac.za)

Co-supervisors: Dr Kutloano E. Sekhosana, Dr Ntuthuko W Hlongwa and Prof Zikhona N Cabunda

There is a growing concern about the pollution of the aquatic environment by environmentally persistent pharmaceuticals pollutants (E3P). Of particular interest are E3P that originate from drugs that are highly prescribed for the treatment of highly contagious diseases that are endemic in South Africa, such as human immunodeficiency virus (HIV). The challenge is the lack of sufficient studies, as well as tools for determine the extent to which the HIV drugs constitute the E3P. In this study, the focus will be on the determination of HIV drug pollutants in environmental surface water, using nevirapine as a model pharmaceutical substance. South Africa has the highest number of HIV patients (4.4 million or 60%) in the world that are undergoing treatment with antiretroviral drugs (ARVs). Optimization of a proof-of-concept electrochemical sensors for upscaling and commercialization is major key in this project.

EXTERNALLY FUNDED PROJECTS

MSc Project

Photodynamic activity of novel transition metal porphyrin complexes conjugated to boron clusters against platonic bacteria in water

Supervisor: Dr ME Managa (managme@unisa.ac.za)

Co-Supervisors: Prof TA Kuvarega and Dr T Masebe

The high fluorescence of metal-free porphyrins causes a dramatic decrease in their reactive oxygen species (ROS) generation. This drawback can be addressed by their versatile synthetic modifications, connecting the pyrrole rings, changing the substituents, and replacing the pyrrole rings with thiophene or furan rings. Furthermore, metalation of porphyrins with zinc(II), indium (III) and tin(IV) has shown a great improvement in their photophysical properties. Therefore, there is a need to develop new porphyrins to mitigate these drawbacks. In this context, it is remarkable that icosahedral boron clusters, especially carborane and metallacarboranes connected to organic fluorophores suppress such π-π interactions due to specific binding modes of the fluorophores to their 3D structures. They provide multiple streams of activation which include light and magnetic fields. Therefore, this will enhance the antimicrobial activity of the nanoconjugates.

MSc Project

Acid Mine Water Treatment

Supervisor: Prof JP Maree (mareejp@unisa.ac.za)

Co-supervisors: Prof M Kebede

Conventional management of mine leachate and desalination brines often relies on evaporation ponds or storage on waste dumps, practices that risk groundwater contamination and are environmentally unsustainable. At a key site in Mpumalanga, leachate from a coal disposal site is partially treated but still presents challenges of salinity, scaling, and brine management.

PhD Project

Removal of trace organic compounds (TrOCs) by high retention membrane bioreactors (HR-MBR)

Supervisor: Prof BB Mamba (mambabb@unisa.ac.za)

Co-supervisors: Dr OT Mahlangu, Dr L Nthunya and Prof AA Muleja

The removal of trace organic compounds (TrOCs) by MF/UF-MBRs depends mainly on the biological activity because MF/UF membranes have poor TrOCs removal. In this work, the application of high-retention membrane bioreactors (HR-MBRs) is proposed to achieve better removal of dissolved solids, organic compounds, nutrients and pathogens by facilitating the biodegradation of organics and physical removal by the membranes in wastewater. Moreover, energy-efficient UF membranes with antifouling and high-solute rejection properties will be prepared for energy efficiency of the proposed system. Herein, commercial pressure driven membrane processes (NF/RO) will be compared to the laboratory prepared low pressure UF membrane to assess the removal performance, fouling and the effects of fouling and cleaning on the membrane performance. Several challenges associated with the proposed system including membrane fouling and salinity build-up will be addressed through advanced pretreatment options, membrane surface modification and the introduction of microfiltration (for intermittent microfiltration experiments). The option to incorporate crude enzymes to enhanced pollutant degradation and reduce sludge production will be looked at. This work is expected to advance knowledge on the removal of TrOCs by HR-MBRs and help improve wastewater treatment efficiency resulting in wastewater reuse and improvement of the Green Drop status.

INDUSTRY BASED PROJECT (PHD PROJECT)

Improving water recovery and fouling mitigation of reverse osmosis membranes applied in landfill leachate treatment

Supervisor: Prof Mxolisi M Motsa (motsamm@unisa.ac.za)

Co-supervisors: Prof LM Madikizela, Dr CS Tshangana and Dr N Motsoane

Solid waste landfills are the most dominant method by which municipalities manage waste generated within their precincts. Overtime, due to physical, chemical and biological processes, there is generation of toxic liquor referred to as landfill leachate and is commonly composed of high levels of organic matter, heavy metals, microbial species, ammonia as well as methane and hydrogen sulphide. Locally, the generic leachate treatment approach involves pre-treatment with granular media, adsorption, centrifugal separation and chlorination. The pre-treatment is followed by a low-pressure membrane process and finally terminated by reverse osmosis which produces clean water to meet the stringent municipal discharge limits for landfill leachate. Additionally, the water can be used within the facilities, irrigation or as retailed supply to other industries.

However, there has been reports on significant challenges in maintaining both the reverse osmosis membrane permeability and permeate quality (product water quality) due to membrane fouling. As a result, the treatment costs get escalated whilst membrane performance and life span is compromised. This study seeks to elucidate the reverse osmosis membrane fouling mechanisms through various feed and membrane analysis and operational conditions. The study will also extend to developing effective membrane cleaning protocols to reduce membrane performance loss and downtime. Most importantly, the study will address the critical question of whether reverse osmosis is the only technology that can guarantee the expected product water quality. The study will be performed in collaboration with a waste management facility that is currently operating several landfill leachate treatment plants in South Africa.

MAMDIWAS ALIGNED PROJECT WITH CO-SUPERVISION FROM GERMANY

PhD project

Pilot study exploring the suitability of a combined demonstration plant for nanofiltration and sequential precipitation for Mine Impacted Wastewater in the Western Basin

Supervisor: Prof Richard M. Moutloali (moutlrm@unisa.ac.za)

Co-supervisors: Jahannes P. Maree and Dr Denga Ramutshatsha-Makhwedzha

The legacy of gold mining on the Witwatersrand basin has left a negative legacy on the current water quality. The natural decent of mine impacted wastewater (MIW) into the catchment areas of the Crocodile and Vaal River as well as local water resources has been devastating and is projected to persist in the future. This wastewater, if properly treated, can be an alternate source of clean water and minerals with economic benefits for both communities and industry. Achieving this goal requires a combined use of two main technologies: sequential and selective precipitation of metal salts followed by membrane filtration to produce water of potable quality standard. The project seeks to explore, on a pilot and continuous scale, the integration of sequential precipitation process and nanofiltration process. In particular, the effect of the first process on the scaling potential for the nanofiltration membranes will form the core aspect of the study. Specific outcomes expected are the effect of the neutralized effluent and membrane surface chemistry manipulation on the scaling potential and protocols to delay and eliminate scaling whilst producing water of potable quality. The project forms part of a long-term pilot study involving both academic and industrial resources.