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This critical review examines the potential of household biogas technology in Africa, focusing on biogas production and techno‐economic feasibility studies. The review highlights the benefits of biogas technology, including renewable energy generation, waste management, and improved public health. A significant portion of Africa's rural population, approximately 60%, grapples with limited access to reliable power sources. The study analyzes various biogas production systems, including anaerobic digesters and biomass gasifiers, and evaluates their economic viability in different African contexts. The review identifies key factors influencing the adoption of household biogas technology, including policy and regulatory frameworks, financing mechanisms, and public awareness. Biogas production stands out as one of the promising renewable energy sources. However, it also discusses the challenges and limitations of implementing this technology on a continental scale. The study analyzes various biogas production systems, including anaerobic digesters and biomass gasifiers, and evaluates their economic viability in different African contexts. The review identifies key factors influencing the adoption of household biogas technology, including policy and regulatory frameworks, financing mechanisms, and public awareness. The study concludes by recommending strategies for scaling up biogas technology in Africa, including capacity building, technology transfer, and innovative financing models. The review aims to provide a comprehensive resource for researchers, policymakers, and practitioners working towards sustainable energy solutions in Africa. [ABSTRACT FROM AUTHOR]

The economies of several countries have benefited significantly from the sugarcane industry, as a result of investment in the industry, foreign exchange earnings, the generation of substantial employment, and connections with significant suppliers. Sugarcane industry participants have been forced to find ways to offset high operating costs due to industry pressures. Proper management of wastes generated from sugar production is essential to reduce the environmental burden of pollution. This study reviews physical, chemical, and biological procedures for reusing or recycling wastewater and other sugar industry waste for various applications. Different countries are continuing to invest in industrial sugar waste, for example biomass and wastewater, to generate renewable energy, but limited investment in the sugar industry in African countries has been identified. Some by‐products, including wastewater and filter cake, have been largely unused for the production of energy. The potential to generate bioenergy from sugarcane industry wastewater has been explored. Numerous technologies for obtaining energy from sugarcane wastewater are reviewed, including the reduction of energy needs through waste heat and process heat integration, generating biomass, combustion and gasification, anaerobic digestion for biogas, fermentation for bioethanol, and the direct production of electricity using microbial fuel cells. Reusing and recycling the sugar industry's waste would increase profits, create more job opportunities, and help to boost the global economy. [ABSTRACT FROM AUTHOR]

Climate change has become a global nightmare, and the awareness of the causes of carbon emissions has resulted in rigorous studies. These studies linked the increase in global warming with booming economic growth. Since global warming has become more apparent, researchers have explored ways to decouple economic activities from carbon growth. Economic and carbon growth must be decoupled to achieve a low-carbon economy to support the carbon-growth plan or emission-reduction strategy. The world is transitioning toward a carbon-neutral and green ecosystem, so finding ways to decouple carbon emissions from economic activities is an exciting topic to explore. This study reviews current information on the importance of decoupling energy from economic growth innovative techniques that thoroughly examine the challenges and constraints of low-carbon energy systems. In order to examine the detrimental effects of carbon emissions on ecosystems and the ways in which economic expansion contributes to carbon footprints, more than three hundred research papers were gathered using several search engines, including Elsevier and Google Scholar. This review revealed that decarbonization and dematerialization had been achieved without declining global economic growth. It also provides information on energy use and economic activities leading to global carbon emissions and alternative solutions to the global challenge of climate change. The decoupling methods commonly used to determine the impact of energy decarbonization on economic growth are explored. All the results suggest that economic growth is a primary mover of global carbon emission increase and must be separated to achieve a carbon environment. [ABSTRACT FROM AUTHOR]

Hybrid ionic fluids (HIFs) are newly emerging and fascinating sustainable solvent media, which are attracting a great deal of scientific interest in protecting the native structure of proteins. For a few decades, there has been a demand to consider ionic liquids (ILs) and deep eutectic solvents (DESs) as biocompatible solvent media for enzymes; however, in some cases, these solvent media also show limitations. Therefore, this work focuses on synthesising novel HIFs to intensify the properties of existing ILs and DESs by mixing them. Herein, HIFs have been synthesised by the amalgamation of a deep eutectic solvent (DES) and an ionic liquid (IL) with a common cation or anion. Later on, the stability and activity of hen's egg white lysozyme (Lyz) in the presence of biocompatible solvent media and HIFs were studied by various techniques such as UV-vis, steady-state fluorescence, circular dichroism (CD), Fourier transform infrared spectroscopy (FT-IR) and dynamic light scattering (DLS) measurements. This work emphasises the effect of a DES (synthesised using 1 : 2 choline chloride and malonic acid) [Maline], ILs (1-butyl-3-methylimidazolium chloride [BMIM]Cl or choline acetate [Chn][Ac]) and their corresponding HIFs on the structure and functionality of Lyz. Moreover, we also studied the secondary structure, thermal stability, enzymatic activity and thermodynamic profile of Lyz at pH = 7 in the presence of varying concentrations (0.1 to 0.5 M) of [BMIM]Cl and [Chn][Ac] ILs, Maline as a DES, and Maline [BMIM]Cl (HIF1) and Maline [Chn][Ac] (HIF2). Spectroscopic results elucidate that ILs affect the activity and structural stability of Lyz. In contrast, the stability and activity are inhibited by DES and are enhanced by HIFs at all the studied concentrations. Overall, the experimental results studied explicitly elucidate that the structure and stability of Lyz are maintained in the presence of HIF1 while these properties are intensified in HIF2. This study shows various applications in biocompatible green solvents, particularly in the stability and functionality of proteins, due to their unique combination where the properties counteract the negative effect of either DESs or ILs in HIFs. [ABSTRACT FROM AUTHOR]

Numerous dye removal techniques have been reported by researchers; however, adsorption and degradation have been identified as the best options due to their low operating costs and greater efficiency. The use of zeolite imidazole based metal organic frameworks (ZIF-MOFs) for dye adsorption and degradation is an effective and preferred approach owing to their desired features such as variable pore diameters and large surface area. Furthermore, there is an increasing interest in using these porous materials to remove toxins from aquatic settings. In this work, two CSM-SA@Ni-MOF composite beads were prepared, evaluated, and used to remove both bromophenol blue (BB, anionic) and malachite green (MG, cationic) dyes from aqueous solutions. Adsorption studies revealed that these materials have good anionic and cationic dye capture ability which is primarily due to the electrostatic interaction between the materials' surface positive or negative charges, as well as the affinity of the interlinked natural adsorbents (chitosan and sodium alginate) for the dyes, and excellent reusability. [ABSTRACT FROM AUTHOR]

The increase in population and urbanization have resulted in an increase in the number of wastewater treatment plants in South Africa. Although wastewater treatment plants serve a great purpose in the reduction of environmentally threatening contaminants from wastewater, the increase in energy consumption by these plants raises concerns about climate change. Thus, there has been a rise in literature attempting to map the energy consumption of wastewater treatment plants to help decision-making in the search for alternative energy sources to promote self-sufficient wastewater treatment plants. There has been a proposition of capturing energy from sewers to mitigate the greenhouse gas emanating from energy consumption by wastewater treatment plants. Literature has proven that sewers can produce 10 times the energy required to operate wastewater treatment plants with the correct factors considered including the characteristics of the wastewater being treated, the technology used, and the management practices employed. This has resulted in a rise in the number of studies investigating biogas production from wastewater treatment plants. Although sewage has been proven to be able to produce sufficient biogas to support the energy requirements of wastewater treatment plants to go off-grid. There are still challenges in the implementation of self-sufficient wastewater treatment plants especially in developing countries such as technological barriers and capital investments. Therefore, this paper will investigate possible ways of making wastewater treatment plants more energy sustainable. Out of many approaches of making WWTP sustainable (resource recovery and energy efficiency improvements); energy generation is the main focus of this mini review. [ABSTRACT FROM AUTHOR]