Sustainable Biofuel Production Research Articles

Cu‐based catalysts for the one‐pot condensation‐hydrogenation of cyclopentanone to produce valuable SAF precursors

A process combining aldol condensation and hydrogenation of bio‐based cyclopentanone (CPO) in a one‐pot reaction is proposed. Cu‐based bifunctional catalysts obtained from hydrotalcite‐type precursors were found highly active in mild reaction conditions (i.e. 130‐170°C), producing valuable bi‐cyclic (C10) and tri‐cyclic (C15) aliphatic alcohols/ketones with interesting application as sustainable aviation fuel (SAF) precursors with enhanced properties. The presence of surficial strong basic sites active in aldol condensation, together with the formation of highly dispersed copper nanoparticles able to catalyze C=C and C=O hydrogenation (TOF of 0.06‐0.16 s‐1), assured high catalytic efficiency and fine control of the products nature and distribution. From the optimization of both catalysts formulation and reaction conditions it was found that, properly tuning the Cu content, it is possible to drive products distribution towards the production of bi‐cyclic C10 aliphatic alcohol with high selectivity (75% at total CPO conversion, when Cu = 10 wt.%, at 170°C, 1.0 MPa of H2) and short reaction time (4h). The optimized catalyst formulation showed impressive stability over multiple reaction/regeneration cycles, demonstrating the high potential of the proposed catalytic process for future applications in sustainable biofuels production.

Efficient Production of Platform Chemicals from Lignocellulosic Biomass by Using Nanocatalysts: A Review

This paper discusses significant advancements in using lignocellulosic biomass for the sustainable production of biofuels and chemicals. As fossil-based resources decline and environmental concerns rise, the paper emphasizes the role of integrated biorefineries in producing renewable liquid fuels and high-value chemicals from biomass. It highlights exploring various green pathways for biomass conversion, with a particular focus on nanocatalysis. Due to their large surface area-to-volume ratio, nanocatalysts provide enhanced catalytic activity and efficiency in biomass transformation processes. The review delves into the synthesis of value-added and furfural platform chemicals alongside the hydrogenolysis of 5-hydroxymethylfurfural (5-HMF) into biofuels like 2,5-dimethylfuran (DMF) and 2,5-dimethyltetrahydrofuran (DMTHF). The paper ultimately underscores the importance of nanotechnology in achieving high yield and selectivity in the biomass conversion process, positioning it as a promising approach for future sustainable energy and chemical production.

Optimization of Hydrocarbon Production in Catalytic Pyrolysis of Macaúba Epicarp and Macaúba and Baru Endocarps

The objective of this study was to examine the catalytic pyrolysis process of three distinct types of biomasses: baru endocarp (ENB), macaúba endocarp (ENM), and macaúba epicarp (EPM). This was performed with the aim of optimizing the production of hydrocarbons and other volatile compounds of interest through the use of different catalysts. The catalysts utilized in this study were calcium oxide (CaO), phosphate mining waste (PO), niobium pentoxide (Nb2O5), and Ni/Nb2O5. The methodology entailed pyrolyzing the biomass at temperatures spanning from 508 °C to 791 °C, utilizing a micropyrolyzer in conjunction with a gas chromatograph with mass spectrometry (GC/MS) for product analysis. An experimental design was implemented to assess the impact of catalyst concentration and temperature on the yield and composition of the volatile products. The findings demonstrated that CaO was efficacious in deoxygenating the compounds, particularly at elevated temperatures, thereby promoting the generation of saturated and unsaturated hydrocarbons. In contrast, Nb2O5 was effective in the formation of oxygenated compounds, particularly carboxylic acids and phenols. Ni/Nb2O5 has been shown to be effective in the production of cyclic, aromatic, alkadienes, and alkenes hydrocarbons. Phosphate mining waste exhibited moderate performance, with potential for specific applications at high temperatures, with important production of cyclic, aromatic, and alkane hydrocarbons. Among the biomasses, EPM demonstrated the greatest potential for hydrocarbon production, indicating its suitability for the development of advanced biofuels. This study advances our understanding of the catalytic pyrolysis of alternative biomasses and underscores the pivotal role of catalysts in optimizing the process, offering invaluable insights for the sustainable production of biofuels and interest in renewable chemicals.

Integration of plant and microbial oil processing at oilcane biorefineries for more sustainable biofuel production

AbstractOilcane—an oil‐accumulating crop engineered from sugarcane—and microbial oil have the potential to improve renewable oil production and help meet the expected demand for bioderived oleochemicals and fuels. To assess the potential synergies of processing both plant and microbial oils, the economic and environmental implications of integrating microbial oil production at oilcane and sugarcane biorefineries were characterized. Due to decreased crop yields that lead to higher simulated feedstock prices and lower biorefinery capacities, current oilcane prototypes result in higher costs and carbon intensities than microbial oil from sugarcane. To inform oilcane feedstock development, we calculated the required biomass yields (as a function of oil content) for oilcane to achieve financial parity with sugarcane. At 10 dw% oil, oilcane can sustain up to 30% less yield than sugarcane and still be more profitable in all simulated scenarios. Assuming continued improvements in microbial oil production from cane juice, achieving this target results in a minimum biodiesel selling price of 1.34 [0.90, 1.85] USD∙L−1 (presented as median [5th, 95th] percentiles), a carbon intensity of 0.51 [0.47, 0.55] kg CO2e L−1, and a total biodiesel yield of 2140 [1870, 2410] L ha−1 year−1. Compared to biofuel production from soybean, this outcome is equivalent to 3.0–3.9 as much biofuel per hectare of land and a 57%–63% reduction in carbon intensity. While only 20% of simulated scenarios fell within the market price range of biodiesel (0.45–1.11 USD∙L−1), if the oilcane biomass yield would improve to 25.6 DMT∙ha−1∙y−1 (an equivalent yield to sugarcane) 87% of evaluated scenarios would have a minimum biodiesel selling price within or below the market price range.

Applications of Machine Learning Technologies for Feedstock Yield Estimation of Ethanol Production

Biofuel has received worldwide attention as one of the most promising renewable energy sources. Particularly, in many countries such as the U.S. and Brazil, first-generation ethanol from corn and sugar cane has been used as automobile fuel after blending with gasoline. Nevertheless, in order to continuously increase the use of biofuels, efforts are needed to reduce the cost of biofuel production and increase its profitability. This can be achieved by increasing the efficiency of a sequential biofuel production process consisting of multiple operations such as feedstock supply, pretreatment, fermentation, distillation, and biofuel transportation. This study aims at investigating methodologies for predicting feedstock yields, which is the earliest step for stable and sustainable biofuel production. Particularly, this study reviews feedstock yield estimation approaches using machine learning technologies that focus on gradually improving estimation accuracy by using big data and computer algorithms from traditional statistical approaches. Given that it is becoming increasingly difficult to stably produce biofuel feedstocks as climate change worsens, research on developing predictive modeling for raw material supply using the latest ML techniques is very important. As a result, this study will help researchers and engineers predict feedstock yields using various machine learning techniques, and contribute to efficient and stable biofuel production and supply chain design based on accurate predictions of feedstocks.

Hydrothermal Valorization of Biosugars with Heterogeneous Catalysts: Advances, Catalyst Deactivation, Mitigation Strategies and Perspectives.

Sustainable production of valuable biochemicals and biofuels from lignocellulosic biomass necessitates the development of durable and high-performance catalysts. To assist the next-stage catalyst design for hydrothermal treatment of biosugars, this paper provides a critical review of (1) recent advances in biosugar hydrothermal valorization using heterogeneous catalysts, (2) the deactivation process of catalysts based on recycling tests of representative biosugar hydrothermal treatments, (3) state-of-the-art understandings of the deactivation mechanisms of heterogeneous catalysts, and (4) strategies for preparing durable catalysts and the regeneration of deactivated catalysts. Based on the review, challenges and perspectives are proposed. Some remarkable achievements in heterogeneous catalysis of biosugars are highlighted. The understanding of catalyst durability needs to be further enhanced based on full examination of the catalytic performance based on the conversion of substrates, the yield, and selectivity of products. Further, a full examination of the physiochemical changes based on multiple characterization techniques is required to eclucidate the relationships between treatment variables and catalyst durability. Collectively, a clear understanding of the relationships between chemical reaction pathways, treatment variables, and the physiochemistry of catalysts is encouraged to be gained to advise the development of heterogeneous catalysts for long-term and efficient hydrothermal upgrading of biosugars.

Hydrothermal liquefaction: exploring feedstock for sustainable biofuel production

A number of technological strategies utilizing various types of biomass for the production of hydrocarbons have been put forth but their energy intensive methods are a concern for improved efficiency of biofuel production. Hydrothermal liquefaction (HTL) has emerged as a promising and feasible technology towards utilization of lignocellulosic biomass. The suitability of different biomass feedstock for HTL is intricately tied to their macromolecular composition and process parameters. The comprehensive analysis of feedstock for hydrothermal liquefaction (HTL) signal towards the immense potential of various biomass feedstock, such as corn stover, Miscanthus, pine biomass, Spirulina, sugarcane bagasse, rice bran etc. in contributing significantly to renewable energy production. The study emphasizes that the composition of biomass is critical in influencing bio-oil yield during the HTL process. Biomass components like cellulose, hemicellulose, and lignin, each play distinct roles in determining the efficiency of conversion. Specifically, feedstock with higher cellulose and hemicellulose content, such as Miscanthus and sugarcane bagasse, demonstrate superior bio-oil yields. The analysis of proximate factors affecting HTL efficiency reveals that moisture content, ash content and high heating value (HHV) are pivotal in optimizing the process. In addition to composition and physical characteristics, the article underscores the significance of growth conditions and nutrient utilization in cultivating biomass feedstock. Integrating HTL with biomass cultivation can create a sustainable, closed-loop system where nutrients from the HTL process are recycled back into cultivation. Biomass offers a renewable energy alternative, however it also poses challenges related to land use and potential competition with food production. Sustainable practices, such as utilizing agricultural and forestry residues and optimizing collection as well as storage processes, can alleviate some of these concerns. By optimizing feedstock selection, process parameters, and integrating sustainable practices, HTL can play a decisive role in advancing biofuel production and contributing to a more sustainable energy future. The interplay between biomass composition, processing efficiency, environmental impacts, and economic feasibility is essential for realizing the full potential of HTL technology in the bio-economy. The current analysis sheds light on the relationship of bio-oil yield with macromolecular components including cellulose, hemicellulose, and lignin as well as process parameters like ash content, moisture content, higher heating value, fixed carbon and volatiles. Focusing on process optimization, this study embodies a closer analysis of literature aimed at defining optimum strategies for enhancement of HTL.

Developing microalgae harvesting: Enhanced efficiency with magnetite-urea nanocomposites for sustainable astaxanthin biorefinery

Harvesting costs, accounting for 15–30 % of total expenses, are a major bottleneck in microalgae biorefinery due to low cell density and energy-intensive processes. This study investigates Fe3O4-Urea (Fe@urea) nanocomposites (NCs) to replace conventional methods and improve the harvesting efficiency (HE) of Chlorella zofingiensis, known for its high lipid and astaxanthin content. Urea-coated magnetite nanoparticles (NPs) with additional functional groups significantly improved harvesting performance across all pH levels compared to conventional Fe3O4 NPs. HE was evaluated using both optical density and cell counting methods, with the latter proving superior results by eliminating interference from unreacted salts and debris. Optimization of nanocomposite concentrations and culture pH with Fe@urea achieves 95 % HE at 800 mg L−1 and pH 3–4. The Langmuir and Freundlich models confirmed the nanocomposite's multifaceted capabilities. Characterization techniques included SEM, FTIR, EDX, zeta potential analysis, and TEM. This innovative approach can revolutionize large-scale microalgae biorefineries, enhancing sustainable biofuel and bioproduct production and supporting the Sustainable Development Goal of Affordable and Clean Energy (SDGs 7).

Bio-Conversion Of Plastic Waste Into Sustainable Biofuels: A Comprehensive Review Of Microbial Degradation Approaches

Plastic's pervasive presence in contemporary society has revolutionized industries and daily life but has concurrently birthed environmental concerns necessitating innovative and sustainable solutions. This review navigates recent strides in plastic-to-fuel conversion, with a particular focus on the transformative potential of microbial degradation. Beginning with a critical assessment of environmental challenges linked to conventional plastic disposal, this review meticulously dissects microbial degradation. Unveiling the intricate processes orchestrated by bacteria and fungi, it delves into the unique advantages this method offers, including reduced land dependency, cost efficiency, and minimal environmental impact, setting it apart from traditional approaches like pyrolysis and gasification. Navigating challenges inherent in plastic-to-fuel conversion, such as energy consumption and emissions, this review synthesizes the latest research, technological breakthroughs, and ongoing initiatives. It culminates in a comprehensive overview of microbial degradation's potential for sustainable plastic waste management and biofuel production. As a synthesis of cutting-edge knowledge, this review not onlyq1 informs current scientific discourse but also charts course for future research, policy, and industrial practices, steering towards a harmonious equilibrium between the benefits of plastic and environmental considerations. This work serves as a beacon for those dedicated to fostering a sustainable future through a nuanced understanding of plastic waste management, environmental sustainability, and the evolving landscape of biofuel production.

Heavea brasilienis (Rubber seed oil) as cost effective non edible feedstock for sustainable high quality biofuel production.

Biodiesel is renewable fuel acquired from biomass which has short chain alkyl esters derived from vegetable oil or animal fats. It has greater advantages over traditional diesel oil. In first level esterification, H2SO4 is used because the acid catalyst to decrease the FFA from 4. 5% to 0. 85 %. In 2nd stage, transesterification chemical process was carried with methanol and NaOH, the elevated temperature 600c and response time is 45 min to 75min. Only a few experiments have been carried out for evaluating the results of equation using a Scientific tool.

Production and optimization of biofuels from locally isolated algal biomass: Strategies for circular economy integration

In the present study, we investigated the potential of locally isolated algal strains as alternative energy sources for sustainable biofuel production. The focus of this study was to identify algal strains that are capable of accumulating oils rich in essential fatty acids. Algal samples were collected from different areas and 14 isolates were obtained. Among the various pretreatment methods tested, hydrothermal pretreatment using sulfuric acid at 95 °C yielded the best results, with sample IIB-14 containing more than 2% reducing sugars. These sugars were then used for fermentation with the S. cerevisiae strain, resulting in an ethanol concentration of 3.52% ± 0.2%. This holistic approach contributes to the development of low-cost and environmentally friendly alternatives to traditional energy sources. While algal biofuels offer a promising substitute for fossil fuels, further advancements are needed before they can be widely adopted in the fuel market. Among these, isolates IIB-8 and IIB-9 showed the highest oil yields of 22.84% and 24.69% (w/w), respectively. The specific environmental settings for optimal growth of these strains were determined, and the physicochemical parameters of the oils, including iodine value, viscosity, density, acid value, saponification value, unsaponifiable mass, and peroxide value, were analyzed. The transesterification of oils into fatty acid methyl esters (FAMEs) revealed the presence of significant amounts of fatty acids, including EPA, DHA, and linoleic acid. Moreover, the study also explored the potential of algal biomass for bioethanol production, addressing the sustainability concerns of renewable energy supplies. Hydrothermal pretreatment using sulfuric acid at 95 °C yielded the highest concentration of reducing sugars (>2%) in IIB-14. Sugar extracted from algal biomass was used for fermentation. The Saccharomyces cerevisiae strain used for the fermentation process yielded an ethanol concentration of 3.52% ± 0.2%. This holistic approach contributes to the development of low-cost and environment-friendly alternatives to renewable energy sources. Algal biofuels may offer a practical substitute for fossil fuels, but there is still a long way to go before they can enter the fuel market and are widely used.

Biomass Resources from Vineyard Residues for the Production of Densified Solid Biofuels in the Republic of Moldova

This paper explores the utilization of biomass resources derived from vineyard residues for producing densified solid biofuels in the Republic of Moldova, with the aim of quantitatively and qualitatively evaluating the residue from vine pruning, focusing on the feasibility of its use as raw material for the production of briquettes and pellets. The methodology includes the analysis of statistical data, as well as experimental investigations conducted at the Scientific Laboratory of Solid Biofuels of the Technical University of Moldova. Waste biomass samples were collected from various vineyards in the different districts of all three regions of the country, focusing on regions with significant plantations. Both quantitative and qualitative aspects of the biomass were assessed, considering the moisture content, calorific value, and ash content. It was found that about 1013 kg/ha of waste biomass is generated from the pruning of technical grape varieties with a net calorific value of 15.6 MJ/kg at a moisture content of 10 wt.% and about 1044 kg/ha with a calorific value of 16.4 MJ/kg from the table ones; both with an average ash content of 3 wt.%. The results indicated that vineyard pruning residues in the Republic of Moldova could provide a substantial biomass source, with an estimated total energy potential of approximately 370 TJ/y (80% located in the Southern region); they also highlighted the need for technological advancements and quality assurance procedures through which to ensure the efficiency and sustainability of biofuel production. The conclusions emphasize the numerous benefits of utilizing viticultural residue, both economically and ecologically, contributing to the sustainable development of the viticulture industry in the Republic of Moldova, as well as environmental protection.

Sustainable Production of Biofuels from Biomass Feedstocks Using Modified Montmorillonite Catalysts.

The rampant exploitation of fossil fuels has led to the significant energy scarcity and environmental disruption, affecting the sound momentum of development and progress of human civilization. To build a closed-loop anthropogenic carbon cycle, development of biofuels employing sustainable biomass feedstocks stands at the forefront of advancing carbon neutrality, yet its widespread adoption is mainly hampered by the high production costs. Montmorillonite, however, has garnered considerable attention serving as an efficient heterogeneous catalyst of ideal economic feasibility for biofuel production, primarily due to its affordability, accessibility, stability, and excellent plasticity. Up to now, nevertheless, it has merely received finite concerns and interests in production of various biofuels using montmorillonite-based catalysts. There is no timely and comprehensive review that addresses this latest relevant progress. This review fills the gap by providing a systematically review and summary in controllable synthesis, performance enhancement, and applications related to different kinds of biofuels including biodiesel, biohydrogenated diesel, levulinate, γ-valerolactone, 5-ethoxymethylfurfural, gaseous biofuels (CO, H2), and cycloalkane, by using montmorillonite catalysts and its modified forms. Particularly, this review critically depicts the design strategies for montmorillonite, illustrates the relevant reaction mechanisms, and assesses their economic viability, realizing sustainable biofuels production via efficient biomass valorization.

A growth-based screening strategy for engineering the catalytic activity of an oxygen-sensitive formate dehydrogenase.

Enzyme engineering is a powerful tool for improving or altering the properties of biocatalysts for industrial, research, and therapeutic applications. Fast and accurate screening of variant libraries is often the bottleneck of enzyme engineering and may be overcome by growth-based screening strategies with simple processes to enable high throughput. The currently available growth-based screening strategies have been widely employed for enzymes but not yet for catalytically potent and oxygen-sensitive metalloenzymes. Here, we present a screening system that couples the activity of an oxygen-sensitive formate dehydrogenase to the growth of Escherichia coli. This system relies on the complementation of the E. coli formate hydrogenlyase (FHL) complex by Mo-dependent formate dehydrogenase H (EcFDH-H). Using an EcFDH-H-deficient strain, we demonstrate that growth inhibition by acidic glucose fermentation products can be alleviated by FHL complementation. This allows the identification of catalytically active EcFDH-H variants at a readily measurable cell density readout, reduced handling efforts, and a low risk of oxygen contamination. Furthermore, a good correlation between cell density and formate oxidation activity was established using EcFDH-H variants with variable catalytic activities. As proof of concept, the growth assay was employed to screen a library of 1,032 EcFDH-H variants and reduced the library size to 96 clones. During the subsequent colorimetric screening of these clones, the variant A12G exhibiting an 82.4% enhanced formate oxidation rate was identified. Since many metal-dependent formate dehydrogenases and hydrogenases form functional complexes resembling E. coli FHL, the demonstrated growth-based screening strategy may be adapted to components of such electron-transferring complexes.IMPORTANCEOxygen-sensitive metalloenzymes are highly potent catalysts that allow the reduction of chemically inert substrates such as CO2 and N2 at ambient pressure and temperature and have, therefore, been considered for the sustainable production of biofuels and commodity chemicals such as ammonia, formic acid, and glycine. A proven method to optimize natural enzymes for such applications is enzyme engineering using high-throughput variant library screening. However, most screening methods are incompatible with the oxygen sensitivity of these metalloenzymes and thereby limit their relevance for the development of biosynthetic production processes. A microtiter plate-based assay was developed for the screening of metal-dependent formate dehydrogenase that links the activity of the tested enzyme variant to the growth of the anaerobically grown host cell. The presented work extends the application range of growth-based screening to metalloenzymes and is thereby expected to advance their adoption to biosynthesis applications.

Production of Bio-Oil from Sugarcane Bagasse through Hydrothermal Liquefaction Processes with Modified Zeolite Socony Mobil-5 Catalyst

In response to the increasing global demand for sustainable energy alternatives, this research explores the efficient conversion of sugarcane bagasse to bio-oil through hydrothermal liquefaction (HTL) processes with modified Zeolite Socony Mobil-5 catalysts (ZSM-5). The study systematically investigates the impact of feedstock quantity, reaction temperature, duration, and catalyst loading on bio-oil yield and quality. Optimisation experiments revealed that a feedstock amount of 10 grammes, an HTL temperature of 340 °C for 60 min and a ZSM-5 catalyst loading of 3 grammes resulted in the highest bio-oil yield. Furthermore, the introduction of Ni and Fe metals to ZSM-5 exhibited enhanced catalytic activity without compromising the structure of the zeolites. Comprehensive characterisation of modified catalysts using SEM-EDS, XRD, TGA, TEM, and FTIR provided insight into their structural and chemical properties. The successful incorporation of Ni and Fe into ZSM-5 was confirmed, highlighting promising applications in hydrothermal liquefaction. Gas chromatography–mass spectrometry (GC-MS) analysis of bio-oils demonstrated the effectiveness of the 2% Fe/ZSM-5 catalyst, highlighting a significant increase in hydrocarbon content. FTIR analysis of the produced bio-oils indicated a reduction in functional groups and intensified aromatic peaks, suggesting a shift in chemical composition favouring aromatic hydrocarbons. This study provides valuable information on HTL optimisation, catalyst modification, and bio-oil characterisation, advancing the understanding of sustainable biofuel production. The findings underscore the catalytic prowess of modified ZSM-5, particularly with iron incorporation, in promoting the formation of valuable hydrocarbons during hydrothermal liquefaction.

Valorization of fish waste for sustainable biofuel production: A case study in Ghana

Fish processing plants generate significant waste annually, which harms the environment. To tackle this, the waste can be converted into biofuel, pharmaceuticals, fertilizer, and animal feed. Biofuels, specifically biogas and biodiesel, are emphasized for their eco-friendly properties that help combat global warming. The study focuses on producing biodiesel through transesterification and biogas via anaerobic digestion of fish waste. Analyses of the rate constant (K), activation energy (Ea), entropy (ΔS), enthalpy (ΔH), and Gibbs free energy (ΔG) at varied temperatures show highest Ea, K, ΔH, and ΔS values of 60.74 kJ/mol, 31.43 s−1, 66.01 kJ/mol, and 30.99 kJ/mol K, respectively. The biodiesel was also characterized by Fourier transform infrared (FTIR) spectroscopy and kinematic viscosity. Additionally, the properties; relative density, viscosity, oxidation stability, pour point, cloud point, flash point, and cetane number were found to be 0.669, 5.090 mm2s−1, >7, −7 °C, 0.999 °C, 151 °C, and 51, respectively. Biogas production using varying ratios of fish waste and cow dung (1:1,1:2, 1:3, and 1:4) indicates that a 1:4 ratio yields optimal results with 69% methane (CH4) and 21.5% carbon dioxide (CO2), suitable for scalable biogas production. The process is efficient at a neutral pH (7.1–7.3) and 27 °C, offering a viable solution to reduce fish waste pollution while generating renewable energy. Finally, a proposed model of a biodigester for optimum biogas production is discussed.

Enhancing bioethanol yield from food waste: Integrating decontamination strategies and enzyme dosage optimization for sustainable biofuel production

Amidst the global surge in energy demand, the public’s focus has shifted from fossil fuels to more sustainable and eco-friendly fuels like bioethanol. Thus, the prospect of producing bioethanol from food waste (FW) is gaining traction, offering a sustainable solution to both waste management and energy needs. However, increasing bioethanol yields during food waste fermentation requires an approach that addresses the variability of these heterogeneous feedstocks in terms of chemical composition, microbial contamination, enzyme dosage requirements, and high moisture content. Hence, this study evaluated thermal and chemical decontamination strategies for pre- and post-consumer food waste and minimised the exogenous enzyme dosage by applying an engineered, amylase-producing strain (Saccharomyces cerevisiae ERT12). Results show that thermal sterilisation at an elevated liquefaction temperature significantly improved ethanol yields (from pre-and post-consumer food waste) more than chemical decontamination methods. Also, key findings show that applying the amylase-secreting yeast reduced enzyme dosages by up to 33 %. During fed-batch fermentation with strain ER T12, the highest possible solids loading increased the final ethanol concentrations by 96 % (for pre-consumer FW) and 85 % (for post-consumer FW) compared to batch fermentation. Also, the pre-consumer to post-consumer FW fed-batch fermentation maintained acceptable volumetric production rates of 2.35 to 1.57 g/l.h and yielded 87.6 to 61.2 % of the theoretical maximum. Although the maximum solids loadings, ethanol titres and yields achievable in food waste fermentations were still limited by the inherent moisture contents of the feed, they demonstrated performances that may be appropriate for industrial implementation, considering the negative feedstock costs.

Advancements in Synthetic Biology for Enhancing Cyanobacterial Capabilities in Sustainable Plastic Production: A Green Horizon Perspective

This comprehensive review investigates the potential of cyanobacteria, particularly nitrogen-fixing strains, in addressing global challenges pertaining to plastic pollution and carbon emissions. By analyzing the distinctive characteristics of cyanobacteria, including their minimal growth requirements, high photosynthetic efficiency, and rapid growth rates, this study elucidates their crucial role in transforming carbon sequestration, biofuel generation, and biodegradable plastic production. The investigation emphasizes cyanobacteria’s efficiency in photosynthesis, positioning them as optimal candidates for cost-effective bioplastic production with minimized land usage. Furthermore, the study explores their unconventional yet promising utilization in biodiesel production, mitigating environmental concerns such as sulfur emissions and the presence of aromatic hydrocarbons. The resulting biodiesel exhibits significant combustion potential, establishing cyanobacteria as a viable option for sustainable biofuel production. Through a comprehensive assessment of both achievements and challenges encountered during the commercialization process, this review offers valuable insights into the diverse contributions of cyanobacteria. Its objective is to provide guidance to researchers, policymakers, and industries interested in harnessing bio-inspired approaches for structural and sustainable applications, thereby advancing global efforts towards environmentally conscious plastic and biofuel production.

Role of cultivation parameters in carbohydrate accretion for production of bioethanol and C-phycocyanin from a marine cyanobacterium Leptolyngbya valderiana BDU 41001: A sustainable approach

The investigation aimed to augment carbohydrate accumulation in the marine cyanobacterium Leptolyngbya valderiana BDU 41001 to facilitate bioethanol production. Under the standardised physiochemical condition (SPC), i.e. 90 µmol photon m−2 s−1 light intensity, initial culture pH 8.5, 35 °C temperature and mixing at 150 rpm increased the carbohydrate productivity ∼70 % than the control, while a 47 % rise in content was obtained under the nitrate (N)-starved condition. Therefore, a two-stage cultivation strategy was implemented, combining SPC at the 1st stage and N starvation at the 2nd stage, resulting in 80 % augmentation of carbohydrate yield, which enhanced the bioethanol yield by ∼86 % as compared to the control employing immobilised yeast fermentation. Moreover, biomass utilisation was maximised by extracting C-phycocyanin, where a ∼77 % rise in productivity was recorded under the SPC. This study highlights the potential of L. valderiana for pilot-scale biorefinery applications, advancing the understanding of sustainable biofuel production.

Highly potent novel SnS2/Zeolite (SFAZ) photocatalyst: An eco-friendly and sustainable strategy for producing biodiesel

Recently, many efforts have been undertaken to advance the development of sustainable biofuel production by transesterifying various oil feedstocks with methanol. In an attempt to contribute in this vein, the current research highlights the synthesis of a novel SnS2/Zeolite (SFAZ) composite photocatalyst for sustainable biodiesel production from soyabean oil through photocatalytic transesterification reaction under visible light irradiation. The reaction parameters influencing the biodiesel yield were optimized using Response Surface Methodology (RSM), and almost complete conversion (99.78 %) of soyabean oil into methyl esters was accomplished at a photocatalyst loading of 3 wt%, methanol-to-oil ratio of 14:1 within 60 min of visible light irradiation at 338 K. The photocatalytic transesterification reaction followed pseudo-first-order kinetics, and the activation energy needed to initiate the transesterification reaction was 28.29 kJ/mol, much lower than other catalysts. The excitation of electrons and the production of holes were required to initiate the transesterification reaction suggested by the scavenger tests, and the photocatalytic mechanism was proposed. The prepared SFAZ composite showed excellent stability and reusability of 80.46 ± 1.13 % in the fifth run. Thus, the current research provides useful insights into sustainable biodiesel production through photocatalytic transesterification reactions under visible light.