Hydrogen-rich syngas fermentation for bioethanol production using Sacharomyces cerevisiea

Bioethanol is an eco-friendly biofuel due to its merit that makes it a top-tier fuel. The present study emphasized on bioethanol production from hydrogen-rich syngas through fermentation using Sacharomyces cerevisiea. Syngas fermentation was performed in a tar free fermenter using a syngas mixture of 13.05% H2, 22.92% CO, 7.9% CO2, and 1.13% CH4, by volume. In the fermentation process, effects of various parameters including syngas impurity, temperature, pH, colony forming unit, total organic carbon and syngas composition were investigated. The yield of bioethanol was identified by Gas chromatography-Mass spectrometry analysis and further, it was confirmed by Nuclear magnetic resonance (1H) analysis. From GC-MS results, it is revealed that the concentration of bioethanol using Saccharomyces cerevisiae was 30.56 mmol from 1 L of syngas. Thus, hydrogen-rich syngas is suited for bioethanol production through syngas fermentation using Saccharomyces cerevisiae. This research may contribute to affordable and environment-friendly bioethanol-based energy to decrease the dependency on fossil fuels. © 2019 Hydrogen Energy Publications LL

Implementation of Carbon Dioxide Gas Injection Method for Gas Recovery at Rashidpur Gas Field, Bangladesh

Natural gas plays an important role for the economic development of Bangladesh. It is the primary options to satisfy the environmentally clean energy, whereas coal is a dirty energy source and oil creates an unhealthy environment. Bangladesh is the seventh-largest producer of natural gas in Asia. Gas supplies meet 56% of domestic energy demand. The proven natural gas reserve in Bangladesh is only 19.73 Tcf. The Rashidpur Gas Field (RGF) is located in the Sylhet Basin, Northeast Bangladesh. It is 35 km long and 7 km anticlinal structure and asymmetric in nature with steeper eastern flank (22˚ to 25˚) and gentler western flank (8˚ to 12˚). There are two gas zones in depth between 1380m to 2787m below surface. Sandstone reservoirs of Miocene-Pliocene age and are considered to have been originated shallow marine depositional environment. The reservoir porosity-permeability values are very good, with estimated gas initially in place (GIIP) of the RGF was 2.242 Tcf with 58% recovery, thus recording an initial gas reserve is 1.309 Tcf. Five gas producing wells (RP-1, 3, 4, 6 and 7) in the RGF are producing 50 MMscf gas per day. Due to the demand of natural gas with decreasing production rate, this enhanced natural gas plays a vital role in the national economy of the country. This research depicts the development of the daily production of the RGF from 50 MMscfd to 99 MMscfd using software from the existing production wells. Thus the natural gas in the RGF would be enhanced/recovered using carbon dioxide (CO2) gas injection by Enhanced Gas Recovery (EGR) method from the RGF reservoir. Applying this method would play a vital role to increase the daily production rate of the RGF

Monitoring of Groundwater Quality in Arsenic and Salinity Prone Areas of Jashore, Bangladesh

The groundwater contamination by arsenic is a large-scale pollution in drinking water history. Safe water supply is a big challenge due to critical hydrogeological situation and water quality problems in this area. The analytical results show that a range of pH, TDS, chloride, total alkalinity, total hardness, sodium, potassium, calcium, magnesium, manganese, iron and arsenic were found between 7.50-7.23, 504.00-201.00 mg/L, 90.30-31.43 mg/L, 410.81-174.31mg/L, 616.47-202.97 mg/L, 52.59-13.28 mg/L, 17.13-2.87 mg/L, 108.57-44.53 mg/L, 83.87-22.29 mg/L, 1.78-0.01 mg/L, 11.78-1.45 mg/L, 0.42-0.02 mg/L, respectively. This study will help making a future plan for groundwater quality monitoring and its hydrogeological application for safe water source identificatio

Hydrogen energy–Potential in developing countries

Energy is essential for human life, societal civilization, and economic growth. Hydrogen energy has emerged as an important component of global energy policies and frameworks, especially in developed countries. This chapter discusses the potential for hydrogen energy in relation to hydrogen production in developing countries. The subsequent sections elaborate on the different sources of hydrogen production, technologies for processing paths, including thermal, electrolytic, photolytic, and fermentation processes. This chapter also focuses on the current and future challenges of hydrogen conversion to electricity. The extraction of hydrogen from renewable and nonrenewable sources presents an appealing potential to realize the maximum environmental value of hydrogen as an electricity carrier. Therefore, the purpose of this chapter is to provide the hydrogen production technologies followed by its present adoption status and future prospect in the developing economies

Application of Electroporation Technique in Biofuel Processing

Biofuels production is mostly oriented with fermentation process, which requires fermentable sugar as nutrient for microbial growth. Lignocellulosic biomass (LCB) represents the most attractive, low-cost feedstock for biofuel production, it is now arousing great interest. The cellulose that is embedded in the lignin matrix has an insoluble, highly-crystalline structure, so it is difficult to hydrolyze into fermentable sugar or cell protein. On the other hand, microbial lipid has been studying as substitute of plant oils or animal fat to produce biodiesel. It is still a great challenge to extract maximum lipid from microbial cells (yeast, fungi, algae) investing minimum energy. Electroporation (EP) of LCB results a significant increase in cell conductivity and permeability caused due to the application of an external electric field. EP is required to alter the size and structure of the biomass, to reduce the cellulose crystallinity, and increase their porosity as well as chemical composition, so that the hydrolysis of the carbohydrate fraction to monomeric sugars can be achieved rapidly and with greater yields. Furthermore, EP has a great potential to disrupt the microbial cell walls within few seconds to bring out the intracellular materials (lipid) to the solution. Therefore, this study aims to describe the challenges and prospect of application of EP technique in biofuels processing

Catalytic gasification of empty palm fruit bunches using charcoal and bismuth oxide for syngas production

The purpose of this research is to evaluate the intent of empty fruit bunches of palm oil (EFBpalm oil) to catalytic gasification of wood produced charcoal (Woodcharcoal) in order to notify the large-scale application of Woodcharcoal as a possible gasification feedstock. In this study, co-catalyst of bismuth oxide (Bi2O3) was also used to obtain syngas. The raw samples were characterized by proximate and ultimate analyses, X-ray diffraction (XRD), field emission scanning electron microscope (FESEM), transmission electron microscopy (TEM) and X-ray photoelectron spectroscopy (XPS) analyses. The produced syngas was analyzed by online portable gas analyzer and gas chromatography-thermal conductivity detector (GC-TCD). The syngas composition of H2 increased from 3.91 to 4.70% (increased 20.20%), CO increased from 5.73 to 6.30% (increased 10.53%), whereas CO2 decreased from 20.60 to 12.67% (decreased 38.50%) and CH4 concentration increased insignificantly from 0.35 to 0.37% (increased 5.7%) which was happened due to the use of WoodCharcoal and Bi2O3 with EFBpalm oil during gasification. According to the findings, carbon is abundant in WoodCharcoal, which may considerably boost the gasification reactivity with Bi2O3. The yield of syngas (H2 and CO) increased when WoodCharcoal and Bi2O3 were used instead of single EFBppo gasification, indicating that catalyst (WoodCharcoal) and co-catalyst (Bi2O3) have a high potential for thermal decomposition and dehydrogenation of volatile matter. Therefore, catalytic gasification of empty palm fruit bunches will be the prospective energy sources for the production of syngas with the utilization of WoodCharcoal and Bi2O3

A comprehensive review on advances in TiO2 nanotube (TNT)-based photocatalytic CO2 reduction to value-added products

The photocatalytic reduction of CO2 into solar fuels by using semiconductor photocatalysts is one of the most promising approaches in terms of pollution control as well as renewable energy sources. One of the crucial challenges for the 21st century is the development of potential photocatalysts and techniques to improve CO2 photoreduction efficiency. TiO2 nanotubes (TNTs) have recently attracted a great deal of research attention for their potential to convert CO2 into useful compounds. Researchers are concentrating more on CO2 reduction due to the rising trend in CO2 emissions and are striving to improve the rate of CO2 photoreduction by modifying TNTs with the appropriate configuration. In order to portray the potential applications of TNTs, it is imperative to critically evaluate recent developments in synthesis and modification methodologies and their capability to transform CO2 into value-added chemicals. The current review provides an insightful understanding of TNT production methods, surface modification strategies used to enhance CO2 photoreduction, and major findings from previous research, thereby revealing research gaps and upcoming challenges. Stability, reusability, and the improved performance of TNT photocatalysts under visible light as well as the selection of optimized modification methods are the identified barriers for CO2 photoreduction into valuable products. Higher rates of efficacy and product yield can be attained by synthesizing suitable photocatalysts with addressing the limitations of TNTs and designing an optimized photoreactor in terms of the proper utilization of photocatalysts, incident lights, and the partial pressure of reactants

Recent progress in TiO2-Based photocatalysts for conversion of CO2 to hydrocarbon fuels: A systematic review

Photocatalytic conversion of CO2 by using sunlight and TiO2 photocatalysts is a promising approach which produce hydrocarbon fuels to meet the future energy demands with hardly affecting the environment. This systematic review aims to provide rigorous overview of recent progress in TiO2-based CO2 photoreduction to produce hydrocarbon fuels along with future challenges. Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) method was adopted to perform this systematic review. It uses explicit systematic approaches that are chosen to prevent bias, resulting in accurate data collection which helps to draw reliable conclusions. Peer-reviewed articles published in English language between year 2018–2022 were chosen from two main databases, namely Web of Science and Scopus. Depending on the search criteria 62 articles were selected for reviewing critically. Literature suggests that TiO2-based photocatalysts have been increasingly used for reducing CO2 to hydrocarbon fuels. Morphological alterations and surface modification techniques have been widely utilized to improve the photocatalytic performance and minimize limitations of pure TiO2. Despite extensible efforts in this field, the utilization of hydrocarbon fuels still far away from practical applications. There are some challenges need to be addressed like environment friendly low-cost synthesis and modification method development, maximum visible light utilization, design of photoreactor with suitable product selectivity and kinetic model development for CO2 reduction. This study portrays increased clarity regarding the advances and way forwards of crucial topics TiO2-based CO2 photoreduction. Such systematic review is crucial for researchers and academicians for setting future planning

Comprehensive characterization and kinetic analysis of coconut shell thermal degradation : Energy potential evaluated via the Coats-Redfern method

Coconut shell represents a promising biomass for energy production, given their wide availability. In this study, the thermo-kinetics of coconut shells were examined through thermogravimetric analysis from 30 °C to 1000 °C at 5 °C/min under N2. Advanced analytical tools assessed the elemental, microstructural, and morphological attributes of the samples. The thermal degradation unveiled three phases: dehydration, devolatilization, and combustion. Notably, the Coats-Redfern method detailed the devolatilization stage, pinpointing the coconut shell's thermal and kinetic attributes. The Zhuravlev diffusion equation (DM6) emerged as the most suitable model, with an activation energy (Ea) and pre-exponential factor of 68.9 kJ mol−1 and 0.05 min−1, respectively. Thermodynamic values such as enthalpy (ΔH), Gibbs free energy (ΔG), and entropy (ΔS) for devolatilization were 65.2, 193.1, and −0.28117, respectively. Collectively, the findings underscore the significant bioenergy potential of coconut shells, positioning them as a sustainable alternative to traditional energy. Such insights play a crucial role in improving pyrolysis reactor designs and comprehending the mechanisms of coconut shell pyrolysis, offering potential solutions for energy deficits and environmental concerns

Advancements in hydrogen generation, storage, and utilizations: A comprehensive review of current trends in Bangladesh

Bangladesh is a developing country heavily reliant on fossil fuels, which emits toxic gases during its combustion. In that scenario, hydrogen is an eco-friendly fuel source with a calorific value of 120 MJ/kg which is significantly higher than fossil fuels. With a density of 0.09 kg/m3 at 273 K, hydrogen is just 1/14th that of air. Considering the enriched agricultural resources of Bangladesh, biomass gasification emerges as the most advantageous method for hydrogen production. Compared to other methods like steam reforming and electrolysis, biomass gasification offers significant cost advantages. Furthermore, being an overpopulated country generates significant organic waste annually. The mismanagement of these wastes creates problematic situations for both lives and surroundings. This review approaches the way of waste management and hydrogen production and additionally discusses the current scenario, several hydrogen production pathways, utilization, and storage. This study focused on hydrogen production and utilization in Bangladesh, which will help the researchers to identify suitable and cost-effective methods to obtain the decarbonization goal in the energy sector