Factors influencing fuel cell life and a method of assessment for state of health

Philosophiae Doctor - PhDProton exchange membrane fuel cells (PEMFC) converts chemical energy from the electrochemical reaction of oxygen and hydrogen into electrical while emitting heat, oxygen depleted air (ODA) and water as by-products. The by-products have useful functions in aircrafts, such as heat that can be used for ice prevention, deoxygenated air for fire retardation and drinkable water for use on board. Consequently, the PEMFC is also studied to optimize recovery of the useful products. Despite the progress made, durability and reliability remain key challenges to the fuel cell technology. One of the reasons for this is the limited understanding of PEMFC behaviour in the aeronautic environment. The aim of this thesis was to define a comprehensive non-intrusive diagnostic technique that provides real time diagnostics on the PEMFC State of Health (SoH). The framework of the study involved determining factors that have direct influence on fuel cell life in aeronautic environment through a literature survey, examining the effects of the factors by subjecting the PEMFC to simulated conditions, establishing measurable parameters reflective of the factors and defining the diagnostic tool based on literature review and this thesis finding

Application of mineralogy in the interpretation of laboratory scale acid rock drainage (ARD) prediction tests : a gold case study

Includes bibliographical references.The mining and beneficiation of gold generates large tonnages of waste, with up to 99% of mined gold ore discharged as waste. The waste generated contains unoxidized sulfides that when exposed to air and water react to form acid, which results in acid rock drainage (ARD). ARD is usually associated with low pH, high sulfate content and elevated concentrations of toxic elements. The mobility of ARD affects our scarce water resources, land and aquatic species. Methods applied to treat ARD do not provide a walk-away solution and they are either expensive or difficult to maintain. The best solution to completely eradicate ARD is to prevent it from the source. However, the effectiveness of ARD prevention depends on the accuracy of predicting future drainage quality. This can be done by using ARD prediction tests, which are generally classified as either static (acid base accounting, ABA, net acid generation, NAG) or kinetic (column leach, humidity cell, biokinetic test). There is no single test capable enough to accurately predict acid generating potential. It is therefore usual practise to conduct more than one test and cross-check results to ensure that the appropriate conclusions are made. In doing so, the reliability of the tests is improved but in some cases the different test results do not correlate. Mineralogy is an analytical technique that can be used to understand the nature of the errors and to better understand the leaching behaviour of minerals in the different tests. This study uses mineralogy to analyse both static and biokinetic test results of a Witwatersrand gold sample in order to improve the understanding of behaviour of mine wastes under different ARD prediction test conditions. A run-of-mine gold sample from the Witwatersrand region in South Africa was used as a case study to explore the mineral leaching behaviour for different ARD prediction tests

Commercialization of green hydrogen production from kraal manure in the Eastern Cape, South Africa: A review

Renewable Energy Independent Power Producer Procurement launched in 2011 contracts renewable energy producers to supplement the national electricity grid. No preferred bidders produce energy using hydrogen fuel cells, particularly Proton Exchange Membrane Fuel Cell (PEMFC), possibly due to technicalities associated with qualifying hydrogen and fuel cells as renewable. The study explores processes to be followed in South Africa to commercialize green hydrogen production for PEMFC from kraal manure. The paper employed an integrative literature review methodology. There are different stages in product commercialisation, such as developing a product, taking the product to markets, growth, and diffusion. The discussions indicate a huge amount of hydrogen that can be produced from kraal manure that is in abundance in the Eastern Cape. Commercialization of hydrogen production can address global economic goals such as waste management, fighting poverty, reducing unemployment and addressing energy challenges.  

Microalgae as a biocathode and feedstock in anode chamber for a self-sustainable microbial fuel cell technology: A review

Microbial fuel cell (MFC) technology has been investigated for over a decade now and it has been deemed as a preferred technique for energy generation since it is environmentally benign and does not produce toxic by/end products. However, this technology is characterized by low power outputs, poor microbial diversity detection, and the presence of methanogenic microorganisms, poor electrochemically active microorganisms’ enrichment techniques, and the type of electrode that is used, amongst others. Furthermore, this technology has relied mostly on refined chemicals for energy production and this practice is not sustainable for long-term application of this technology. This paper reviews the use of a microalgae-assisted MFC for a self-sustainable microbial fuel cell where a microalgae-assisted cathode is established to facilitate the oxidation/reduction reactions (ORR) while recycling the generated algal biomass to the anode compartment as a feedstock for improved energy generation. Furthermore, this review proposes for the utilization of cell disruption techniques to maximize nutrient availability for maximal power generation while also making use of molecular diagnostic tools such as metagenomics and metatranscriptomics to monitor the microbial community structure and function

Microalgae as a biocathode and feedstock in anode chamber for a selfsustainable microbial fuel cell technology : a review

Abstract:Microbial fuel cell (MFC) technology has been investigated for over a decade now and it has been deemed as a preferred technique for energy generation since it is environmentally benign and does not produce toxic by/end products. However, this technology is characterized by low power outputs, poor microbial diversity detection, and the presence of methanogenic microorganisms, poor electrochemically active microorganisms’ enrichment techniques, and the type of electrode that is used, amongst others. Furthermore, this technology has relied mostly on refined chemicals for energy production and this practice is not sustainable for long-term application of this technology. This paper reviews the use of a microalgae-assisted MFC for a self-sustainable microbial fuel cell where a microalgae-assisted cathode is established to facilitate the oxidation/reduction reactions (ORR) while recycling the generated algal biomass to the anode compartment as a feedstock for improved energy generation. Furthermore, this review proposes for the utilization of cell disruption techniques to maximize nutrient availability for maximal power generation while also making use of molecular diagnostic tools such as metagenomics and metatranscriptomics to monitor the microbial community structure and function

Entrepreneurship education to stimulate entrepreneurial mindset in chemistry students

Chemistry is a field of study that teaches students critical skills in producing day-to-day products ranging from detergents, cosmetics, energy components and supplies for treating water. The majority of chemistry students seek formal employment after completing their studies, which helps to explain the increased incidence of unemployed South African graduates. This occurrence is more apparent in the Eastern Cape where there are very few chemistry industries with such employment opportunities. However, having an entrepreneurial mindset can lead to students venturing into business during or after their studies. Student businesses not only benefit the student but the community with accessible personalized solutions to their problems, institutions with reputation, creating a circular economy and possibly employment of others. Hence, this study aims to evaluate whether the offered entrepreneurship education to chemistry students stimulates an entrepreneurial mindset. The paper employed the qualitative narrative literature review methodology and the connectivism learning theory to achieve the set aim. Explored themes in realizing the aim are graduate attributes, science-based entrepreneurship education and entrepreneurial mindset. The key findings are that science-based entrepreneurship education lacks the embedment of fundamental chemistry that creates familiarity with the concept and subsequent relatability with the course content. The connectivism learning theory supports the link between familiarity and new learning opportunities whereby, in this case, an entrepreneurial mindset can be stimulated. The study proposes that entrepreneurship education for chemistry students must include chemistry-related case studies and a participatory practical approach as a co-curricula. The co-curricula aspect will involve opportunities to start a real business on campus during the semester in which the course is offered

Can enabling entrepreneurship ecosystem improve commercialization of research in South African Higher Education Institutions?

An entrepreneurship ecosystem entails a community of practice that displays the characteristics of creativity and innovation, risk-taking, a strategist, and an active participant in identifying opportunities and making decisions among others in the organization. The ecosystem can be key when Higher Education Institutions are engaged in the transformation process of commercialization. The paper intends to explore whether an entrepreneurship ecosystem can stimulate the commercialization of the research process in a sustainable way. The qualitative thematic review methodology is employed to achieve this aim. The commercialization process is viewed in an entrepreneurship ecosystem by looking at the entrepreneurial institutions, stakeholders involved, and the sustainable business model. It is recommended that adopting an entrepreneurial ecosystem for commercialization of research in Higher Education Institutions can play a crucial role in building their structures to be economically active; addressing graduate unemployment; providing recovery strategies to reboot businesses in communities, especially after the COVID-19 pandemic; and position themselves as entrepreneurial institutions

Entrepreneurship education to stimulate entrepreneurial mindset in chemistry students

Chemistry is a field of study that teaches students critical skills in producing day-to-day products ranging from detergents, cosmetics, energy components and supplies for treating water. The majority of chemistry students seek formal employment after completing their studies, which helps to explain the increased incidence of unemployed South African graduates. This occurrence is more apparent in the Eastern Cape where there are very few chemistry industries with such employment opportunities. However, having an entrepreneurial mindset can lead to students venturing into business during or after their studies. Student businesses not only benefit the student but the community with accessible personalized solutions to their problems, institutions with reputation, creating a circular economy and possibly employment of others. Hence, this study aims to evaluate whether the offered entrepreneurship education to chemistry students stimulates an entrepreneurial mindset. The paper employed the qualitative narrative literature review methodology and the connectivism learning theory to achieve the set aim. Explored themes in realizing the aim are graduate attributes, science-based entrepreneurship education and entrepreneurial mindset. The key findings are that science-based entrepreneurship education lacks the embedment of fundamental chemistry that creates familiarity with the concept and subsequent relatability with the course content. The connectivism learning theory supports the link between familiarity and new learning opportunities whereby, in this case, an entrepreneurial mindset can be stimulated. The study proposes that entrepreneurship education for chemistry students must include chemistry-related case studies and a participatory practical approach as a co-curricula. The co-curricula aspect will involve opportunities to start a real business on campus during the semester in which the course is offered

Can enabling entrepreneurship ecosystem improve commercialization of research in South African Higher Education Institutions?

An entrepreneurship ecosystem entails a community of practice that displays the characteristics of creativity and innovation, risk-taking, a strategist, and an active participant in identifying opportunities and making decisions among others in the organization. The ecosystem can be key when Higher Education Institutions are engaged in the transformation process of commercialization. The paper intends to explore whether an entrepreneurship ecosystem can stimulate the commercialization of the research process in a sustainable way. The qualitative thematic review methodology is employed to achieve this aim. The commercialization process is viewed in an entrepreneurship ecosystem by looking at the entrepreneurial institutions, stakeholders involved, and the sustainable business model. It is recommended that adopting an entrepreneurial ecosystem for commercialization of research in Higher Education Institutions can play a crucial role in building their structures to be economically active; addressing graduate unemployment; providing recovery strategies to reboot businesses in communities, especially after the COVID-19 pandemic; and position themselves as entrepreneurial institutions

Commercialization of green hydrogen production from kraal manure in the Eastern Cape, South Africa: A review

Renewable Energy Independent Power Producer Procurement launched in 2011 contracts renewable energy producers to supplement the national electricity grid. No preferred bidders produce energy using hydrogen fuel cells, particularly Proton Exchange Membrane Fuel Cell (PEMFC), possibly due to technicalities associated with qualifying hydrogen and fuel cells as renewable. The study explores processes to be followed in South Africa to commercialize green hydrogen production for PEMFC from kraal manure. The paper employed an integrative literature review methodology. There are different stages in product commercialisation, such as developing a product, taking the product to markets, growth, and diffusion. The discussions indicate a huge amount of hydrogen that can be produced from kraal manure that is in abundance in the Eastern Cape. Commercialization of hydrogen production can address global economic goals such as waste management, fighting poverty, reducing unemployment and addressing energy challenges.  &nbsp