Search

Abstract This research seeks to comprehensively assess the water footprint and environmental sustainability of millet-based ethanol production in India, responding to the growing interest in resilient and nutritious alternatives. Utilizing a life cycle assessment approach, the study will scrutinize water usage across the entire production process, from millet cultivation to ethanol extraction. The primary aim is to gain an in-depth understanding of water consumption at each stage, pinpointing areas for enhancement and efficiency. Rajasthan exhibited the highest total water footprint at 6596 m3/ton, primarily due to its substantial ETc value, while Andhra Pradesh showcased the lowest at 1906 m3/ton, owing to its high average yield. Haryana displayed significant water usage during crop production, with a water footprint of 5870 m3/ton, where WFgreen, WFblue, and WFgrey contributed 3730 m3/ton, 2010 m3/ton and 130 m3/ton respectively. Uttar Pradesh demonstrated a comparatively lower total water footprint of 2564 m3/ton. These findings are anticipated to offer valuable insights into the viability and sustainability of millet-derived ethanol as an eco-friendly biofuel option in India, guiding policymakers, researchers, and stakeholders in promoting its adoption and addressing environmental challenges linked with conventional fuel sources.

This research seeks to comprehensively assess the water footprint and environmental sustainability of millet-based ethanol production in India, responding to the growing interest in resilient and nutritious alternatives. Utilizing a life cycle assessment approach, the study will scrutinize water usage across the entire production process, from millet cultivation to ethanol extraction. The primary aim is to gain an in-depth understanding of water consumption at each stage, pinpointing areas for enhancement and efficiency. Rajasthan exhibited the highest total water footprint at 6596 m3/ton, primarily due to its substantial ETc value, while Andhra Pradesh showcased the lowest at 1906 m3/ton, owing to its high average yield. Haryana displayed significant water usage during crop production, with a water footprint of 5870 m3/ton, where WFgreen, WFblue, and WFgrey contributed 3730 m3/ton, 2010 m3/ton and 130 m3/ton respectively. Uttar Pradesh demonstrated a comparatively lower total water footprint of 2564 m3/ton. These findings are anticipated to offer valuable insights into the viability and sustainability of millet-derived ethanol as an eco-friendly biofuel option in India, guiding policymakers, researchers, and stakeholders in promoting its adoption and addressing environmental challenges linked with conventional fuel sources. [ABSTRACT FROM AUTHOR]

Sugarcane (Saccharum sp. hybrid complex) is an important industrial crop as a source of food and bio-energy. Its juice can act as a cheaper renewable substrate for bio-ethanol production because it contains free sugars like sucrose or monosaccharides (especially, glucose) that can be directly converted into ethanol via fermentation with the help of microorganisms. The present study reports on bio-ethanol production potential of 22 different sugarcane varieties/clones (early and mid-late) that were initially screened for cane yield and components traits, physiological and juice quality traits. Among 22 clones/varieties, six varieties viz, CoPb 95, CoPb 92, Co 0118, CoPb 93, CoJ 88, and Co 0238, were identified for good bio-ethanol production potential on the basis of leaf area (cm2), fresh weight (kg), Brix (%), extraction (%) and fiber (%) cane. These varieties were further evaluated for other biochemical traits and bio-ethanol production potential under laboratory scale and scale-up studies using yeast strain (Saccharomyces cerevisiae MK 680910). Two varieties CoPb 92 (early) and CoJ 88 (mid-late) having higher initial sugars and ethanol content under laboratory scale were selected as potential sugarcane varieties for scale-up studies. Study at 5 L scale reported that CoPb 92 variety exhibiting initial Brix (20.97%), total sugars (20.05 g/100 mL), and reducing sugars (0.567 g/100 mL), yielded 12.40 (%v/v) initial ethanol content with fermentation efficiency of 96.21 (%) and ethanol yield 0.50 (g/g) in early group. After double distillation of the fermented wort, the ethanol content of 78.46% (v/v) was achieved with ethanol recovery of 0.329 L. Similarly, variety CoJ 88 reporting initial Brix (20.24%), total sugars (19.88 g/100 mL), and reducing sugars (0.814 g/100 mL juice) yielded initial ethanol content of 11.68 (%v/v) with fermentation efficiency of 94.49 (%) and ethanol yield of 0.47 (g/g) in mid-late group. Recovery of 0.301 L ethanol was obtained after double distillation with ethanol content of 75.45 (%v/v). The sustainability of economy/ revenue of sugar industry relies on either reduction in the production cost of sugar or to divert sugar industry toward energy and power generation. Therefore, a cultivar intended for the production of ethanol ought to possess elevated levels of total sugars or percentage of commercial cane sugar, in conjunction with a substantial cane yield. The information generated in the present study can be added as a basic input to scale-up technical process toward enhancing the production of bio-fuel in sugar industries by switching over from sole sugar production to ethanol production, depending on the situations (sugar deficit/sugar surplus) in the market. [ABSTRACT FROM AUTHOR]

Zymomonas mobilis is a gram-negative facultative anaerobic spore, which is generally recognized as a safe. As a promising ethanologenic organism for large-scale bio-ethanol production, Z. mobilis has also shown a good application prospect in food processing and food additive synthesis for its unique physiological characteristics and excellent industrial characteristics. It not only has obvious advantages in food processing and becomes the biorefinery chassis cell for food additives, but also has a certain healthcare effect on human health. Until to now, most of the research is still in theory and laboratory scale, and further research is also needed to achieve industrial production. This review summarized the physiological characteristics and advantages of Z. mobilis in food industry for the first time and further expounds its research status in food industry from three aspects of food additive synthesis, fermentation applications, and prebiotic efficacy, it will provide a theoretical basis for its development and applications in food industry. This review also discussed the shortcomings of its practical applications in the current food industry, and explored other ways to broaden the applications of Z. mobilis in the food industry, to promote its applications in food processing. Potential applications of Zymomonas mobilis in food industry summarized for the first time. Research status of Z. mobilis in food additive synthesis, fermentation applications, and probiotics are discussed in details. Future research perspectives of Z. mobilis in food industry further proposed. [ABSTRACT FROM AUTHOR]

Bio-ethanol is a promising renewable energy but its production is expensive from high cost of feedstocks. In this study, sweet sorghum (Sorghum bicolor (L.) Moench) stalk juice was investigated for bio-ethanol production. Most reports on bio-ethanol productions use commercial Saccharomyces cerevisiae as yeast. However, this study used finger millet (Eleusine coracana) malt with already high adaptation to local conditions and high economic viability as it is being utilized by the indigenous communities. Five sweet sorghum varieties of IESV-92001-DL (V1), NTJ (V2), 15233-IESV (V3), 92008-DJ (V4) and IESV-92028-DL (V5) were planted at 0°3'45.4644" North, 34°17'16.1052" South, in Kenya. °Brix content of juice was determined at 11th to 16th weeks after sowing. Highest °Brix for all varieties were at 15th week where V1 was highest at 22.07. V1 was then harvested for the juice. Factors affecting fermentation; temperature, time, pH and yeast to substrate ratio were optimized using Taguchi method and were obtained as 30 °C, 48 hours, pH 5 and 5 g/L, respectively. Kinetics parameters of Vmax and Km were 0.35 g/L/h and 12.56 g/L, respectively. The optimized and kinetic parameters were within literature values and therefore finger millet malt has a great potential, as a substitute yeast source, in commercial bio-ethanol production. [ABSTRACT FROM AUTHOR]

One way to mitigate the adverse impacts of climate change is through aggressive replacement of fossil energy sources with plant derived renewable energy. The potential of different grades of cassava starch, including decayed cassava starch, as viable alternative and cheaper source of renewable raw materials for bio-ethanol production was studied. The global population keeps expanding and poverty levels keep increasing. Conflict in the use of food-grade cassava starch as raw material for bio-ethanol production will pose a threat to food security. The highest alcohol yield (AY) of 539 LA/t dm was obtained from food grade cassava starch. Food grade cassava starch per-boiled for 5 min produced lower AY (524 LA/t dm). Cassava starch per-boiled for more than 5 min gave much lower AY (507 LA/t). The mildly decayed cassava starch gave a relatively higher AY of 491 LA/t dm than the more decayed cassava substrate that produced AY of 453 LA/t dm. The AY value obtained from the more decayed cassava starch is similar to the AY values obtained with some cereals. Decayed cassava is not fit for human consumption, would not compete with food requirements. This will assist in food security, secure our environment from pollution and other adverse effects.

Copyright of Chemical Engineering (China) / Huaxue Gongcheng is the property of Hualu Engineering Science & Technology Co Ltd. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Microalgae have a high growth rate, high CO2 absorption capacity, and high content of chlorophyll, proteins, vitamins, mineral salts, carbohydrates, antioxidant substances, and fatty acids. In recent years, Chlorella vulgaris has been widely used as a feedstock for producing third-generation biofuels, such as bioethanol. Thus, this work aims to develop a strategy to increase the production scale of the microalgae Chlorella vulgaris grown in distilled reused water, supplemented with a modified BG-11 medium, to use biomass in the production of bioethanol. The total cultivation of 72 L presented a concentration of 0.415 g·L−1·d−1, with 61.32 g of final biomass. To improve carbohydrate extraction, the biomass was pre-treated with sulfuric acid at different concentrations (1.5% and 3% v/v). The hydrolyzed solution was supplemented with YPD (yeast extract peptone dextrose) medium and inoculated with Saccharomyces cerevisae yeast, initiating fermentation. In each sample, the Brix degree, cell concentration, reducing sugar concentration, and alcohol content were analyzed. The sample pre-treated with sulfuric acid 1.5% v/v was the one that presented the best result, with alcohol content after distillation of 68 °GL (Gay-Lussac). It appears that the cultivation of the microalgae Chlorella vulgaris in scale-up, with reused water, has high potential in the production of third-generation biofuel.

Biofuels have attracted a lot of attention due to the growing demand for energy resources and concerns about greenhouse gas emissions. Unlike other green energy resources, biofuels like bioethanol, can provide liquid fuels that is essential for transportation. Second-generation bioethanol can be produced from lignocellulosic biomass through acid hydrolysis and fermentation. Lignocellulosic biomass is widely available and does not affect on the nutritional needs of agricultural crops. In this study, the aquatic plant Ceratophyllum demersum was used. Ceratophyllum demersum is a type of invasive aquatic plant that can live in fresh and brackish waters, and it is abundant in most regions of southern Iraq. The bioethanol with the highest concentration was identified by high-performance liquid chromatography (HPLC). The results showed that 14% of bioethanol was produced in the absence of acid hydrolysis, while the concentration of it increased to 25% with the presence of acid hydrolysis. Acid hydrolysis aims to increase the breaking bonds of lignin and hemicellulose, increase the porosity of the material, and damage the crystalline structure of cellulose, and thus facilitates its conversion to glucose and increases the percentage of ethanol production.

Microalgae have a high growth rate, high CO2 absorption capacity, and high content of chlorophyll, proteins, vitamins, mineral salts, carbohydrates, antioxidant substances, and fatty acids. In recent years, Chlorella vulgaris has been widely used as a feedstock for producing third-generation biofuels, such as bioethanol. Thus, this work aims to develop a strategy to increase the production scale of the microalgae Chlorella vulgaris grown in distilled reused water, supplemented with a modified BG-11 medium, to use biomass in the production of bioethanol. The total cultivation of 72 L presented a concentration of 0.415 g·L−1·d−1, with 61.32 g of final biomass. To improve carbohydrate extraction, the biomass was pre-treated with sulfuric acid at different concentrations (1.5% and 3% v/v). The hydrolyzed solution was supplemented with YPD (yeast extract peptone dextrose) medium and inoculated with Saccharomyces cerevisae yeast, initiating fermentation. In each sample, the Brix degree, cell concentration, reducing sugar concentration, and alcohol content were analyzed. The sample pre-treated with sulfuric acid 1.5% v/v was the one that presented the best result, with alcohol content after distillation of 68 °GL (Gay-Lussac). It appears that the cultivation of the microalgae Chlorella vulgaris in scale-up, with reused water, has high potential in the production of third-generation biofuel. [ABSTRACT FROM AUTHOR]

Bioethanol (15 wt%) derived from waste rice straw blended with diesel [e-diesel (B15)] and tested in a variable compression ratio (VCR) compression ignition (CI) engine with compression ratios of 14 and 18 under 0% and 100% load conditions. The engine performances of diesel fuel with 25, 50, 75 ppm of Al2O3 nanoparticles [nanofuel (N25, N50, N75)] and B15 with 25, 50, 75 ppm of Al2O3 nanoparticles [nanofuel (NB25, NB50, NB75)] are next investigated similarly. The performance measures investigated are energy efficiency, exergy efficiency, brake specific fuel consumption (BSFC), heat release rate (HRR), peak cylinder pressure, and CO, HC, and NOx emissions. The cost of e-diesel and nanofuels are predicted using economic analysis and compared to regular diesel (D) fuel. Other parameters, with BSFC exception, are observed to increase as load changes from 0 to 100%. From different fuel types, N75 exhibits maximum energy efficiency of 34.3%, exergy efficiency of 65.27%, heat release rate of 68 J/crank angles, peak cylinder pressure of 84.1 bar, the relative cost of −14.63%, minimum BSFC of 0.449 kg/kW-hr, CO emission of 0.2%, and HC emission of 32 ppm for maximum load and compression ratio conditions, whereas the N50 exhibit minimum NOx emission of 398 ppm.

The organic fraction of municipal solid waste (OFMSW) and refuse-derived fuel (RDF) mainly consisting of paper/cardboard can be used as feedstock for the production of cellulosic ethanol. In this paper, an efficient technology is described to convert waste paper/cardboard into cellulosic ethanol. The process involves separation of the OF from the other components in the waste stream. An acid pretreatment is used to liberate the cellulosic fibers and the accessibility of the enzyme Cellic CTEC3 loading 3.75–11.25 FPU/g paper in a fed-batch addition up to 22.5% solid yield, 15 g sugars/l with a saccharification yield up to 90%. A semi-simultaneous fermentation process (SSFP) with a saccharomyces cerevisae strain MDS130 capable of fermenting both pentoses and hexoses are growing an ethanol titer (%v/v) of 8.4% on pilon-plant scale.

This paper presents a study on the performance and emission characteristics of a currently used motorcycle fueled with either gasoline or ethanol at cold starting and idling condition. The engine's fuel system was modified by extending the injection pulse width to allow it to operate with pure ethanol or gasoline. The ethanol-fueled engine required three to four cranking times to achieve success starting at an ambient temperature between 15°C and 20°C. In cold idling conditions, the ethanol-fueled engine operated at a high coefficient of variation of speed (COVspeed) of 1.20% to 2.49% at an ambient temperature of 17°C, while a COVspeed of 0.92% of the gasoline-fueled engine was observed. However, with the aid of the electric-based heating system (EHS), the ethanol-fueled engine performance was enhanced significantly as the COVspeed was 0.95% at 15°C, 0.85% at 17°C, and 0.73% at 20°C in idling condition and achieved successful starting at the first time of cranking after 30 s of pre-heating. During the warm-up stage, a significant fluctuation of emission was observed with different test cases. However, with the heating system, the engine enhanced completed combustion quicker as incomplete combustion products of HC and CO were reduced rapidly in idling compared to gasoline and ethanol-fueled engine. NOx emissions increased with the aid of the heating system but were still lower compared to the gasoline-fueled engine during idling condition. [ABSTRACT FROM AUTHOR]

The optimization of production and characterization of bio-fuel produced by enzyme fermentation of hydrolyzed mixed peel (cassava and potato peels) were carried out. Proximate analysis was used to characterize the substrate and response surface methodology was employed to optimize the fermentation process parameters while the kinetics and thermodynamics of the bio-ethanol production by enzyme fermentation were studied using Michealis-Menten model. The result obtained showed that the mixed peels contained hydrolyzable cellulose. The optimum conditions for the bio-ethanol yield of 80% by enzymatic (yeast) fermentation are temperature, 46oC, time, 6days, pH 5.7 and enzyme dosage, 2.2ml. The kinetics studies of the enzymatic (yeast) fermentation of hydrolyzed mixed peel obeyed the Michealis-Menten kinetic model and the reaction was feasible. The properties of the bio-ethanol were similar to normal ethanol. Therefore, the result has proved that hydrolyzable sugar from mixed Peels (Cassava and potato peels) is a good substrate for bio-ethanol production as biofuel via enzymatic fermentation.

Mixed matrix membranes (MMMs) have shown great potential in pervaporation (PV). As for many novel membrane materials however, lab-scale testing often involves synthetic feed solutions composed of mixed pure components, overlooking the possibly complex interactions and effects caused by the numerous other components in a real PV feed. This work studies the performance of MMMs with two different types of fillers, a core-shell material consisting of ZIF-8 coated on mesoporous silica and a hollow sphere of silicalite-1, in the PV of a real fermented wheat/hay straw hydrolysate broth for the production of bio-ethanol. All membranes, including a reference unfilled PDMS, show a declining permeability over time. Interestingly, the unfilled PDMS membrane maintains a stable separation factor, whereas the filled PDMS membranes rapidly lose selectivity to levels below that of the reference PDMS membrane. A membrane autopsy using XRD and SEM-EDX revealed an almost complete degradation of the crystalline ZIF-8 in the MMMs. Reference experiments with ZIF-8 nanoparticles in the fermentation broth demonstrated the influence of the broth on the ZIF-8 particles. However, the observed effects from the membrane autopsy could not exactly be replicated, likely due to distinct differences in conditions between the in-situ pervaporation process and the ex-situ reference experiments. These findings raise significant questions regarding the potential applicability of MOF-filled MMMs in real-feed pervaporation processes and, potentially, in harsh condition membrane separations in general. This study clearly confirms the importance of testing membranes in realistic conditions.

A polysaccharide molecule called starch exists in nature and is cheap, renewable, biodegradable, and readily accessible. The main objective of this project is to extract and characterize anchote (Coccinia abyssinica) starch, as well as to generate bio-ethanol from its pulp/waste. The anchote sample used in this investigation came from Ethiopia’s western Oromia region. Anchote (Coccinia abyssinica) starch was extracted, and the pulp from the tuber was peeled and the supernatant isolated for bio-ethanol production. The extracted starch from anchote and bio-ethanol from pulps were characterized by physicochemical, functional properties and FT-IR analysis. The result of physicochemical and functional properties of anchote starch was found to be pH (4.44), WHC (112%), Solubility (5.03%), swelling power (5.781%), Gelatinization temperature (53.33 °C), WAC (2 g/g), bulk density (0.605 g/cm3) and OAC (3 g/g). According to this FTIR research, anchote starch has a chemical structure that is similar to corn, cassava, and potato starch. As the results showing a promising alcoholic content (25% v/v) and the existence of bioethanol being validated by a combustion test, the pulps/wastes recovered from anchote are also good sources of bioethanol. Finally, the FTIR spectroscopic analysis revealed that ethyl alcohol was produced from anchote pulps/waste after acid hydrolysis, fermentation, and distillation.

The organic fraction of municipal solid waste (OFMSW) and refuse-derived fuel (RDF) mainly consisting of paper/cardboard can be used as feedstock for the production of cellulosic ethanol. In this paper, an efficient technology is described to convert waste paper/cardboard into cellulosic ethanol. The process involves separation of the OF from the other components in the waste stream. An acid pretreatment is used to liberate the cellulosic fibers and the accessibility of the enzyme Cellic CTEC3 loading 3.75–11.25 FPU/g paper in a fed-batch addition up to 22.5% solid yield, 15 g sugars/l with a saccharification yield up to 90%. A semi-simultaneous fermentation process (SSFP) with a saccharomyces cerevisae strain MDS130 capable of fermenting both pentoses and hexoses are growing an ethanol titer (%v/v) of 8.4% on pilon-plant scale. [ABSTRACT FROM AUTHOR]

The design and preliminary estimations of biomass supply chains are essential in matching energy supply to energy demand. This is especially true of novel/future fuels and technologies in large industries. In this paper, a Mixed Integer Linear Programming (MILP) model was formulated to represent biofuel supply chains across Europe for the production of three novel marine fuels and to allow the selection of fuel conversion technologies, biomass supply locations, and the logistics of transportation from resources to conversion and from conversion to final markets. On top of this, the total production costs and emissions were calculated and compared to current marine fuels to assess the implementation potential and feasibility of these fuels. The MILP model was used to design and analyze optimal distribution and conversion systems, using a realistic data-set covering the European member states and 15 of the largest bunkering ports in the EU. The results showed that on average, the fuels obtained a 72% greenhouse gas (GHG) reduction compared to a fossil fuel comparator and ranged from 22–36 €/GJ in total production costs. It was also discovered that forestry residues were the best-suited biomass for the production of these fuels and that Poland had the highest supply potential of all considered states. The available supply of biomass was sufficient for the demand in the foreseeable future, the largest impediment to the adoption of these fuels is the available refining potential in Europe.

Often, clean energy concept is tagged with the bio-ethanol production from the agricultural sources. Herein, we are first to report on use of nanoscale materials (nano-CaO and nano-MgO) in fermentation process for bio-ethanol production from nanoscale materials (zinc, calcium and magnesium)-driven bio-fortified sweet sorghum. A field experiment was conducted during 2014 and 2015, and nanoscale materials of CaO and MgO (mean size 69.6 nm and 42 nm) at concentrations of 10 ppm and 20 ppm, respectively, alone and in combination were added during the fermentation process. Ethanol production significantly increased by 24.7% and 17.5% by adding nano-CaO and nano-MgO, respectively. Significantly higher ethanol content (8.83% and 8.94%) was recorded in the treatment which received nanoscale-driven bio-fortified sweet sorghum juice with added nanoscale nutrients (CaO and MgO) during fermentation process. Thus, nanoscale materials increase the rate of fermentation process which may lead to the enhanced bio-ethanol production. [ABSTRACT FROM AUTHOR]

This paper discusses the epochal change in the reputation of carbon dioxide, which is now considered as a raw material alternative to fossil C for the synthesis of chemicals, materials and fuels, as opposed to a waste material that must be confined underground. In particular, its use as renewable C is compared to biomass. In this paper, a specific point is discussed: is ethanol (or any fuel) produced via the catalytic conversion of atmospheric CO2 different from the relevant biomass-sourced product(s)? The answer to this question is very important because it ultimately determines whether or not fuels derived from atmospheric CO2 (either e-fuels or solar fuels) have the right to be subsidized in the same way that biofuels are. Conclusions are drawn demonstrating that ethanol derived from atmospheric CO2 deserves the same benefits as bio-ethanol, with the additional advantage that its synthesis can be less pollutant than its production via the fermentation of sugars. The same concept can be applied to any fuel derived from atmospheric CO2. [ABSTRACT FROM AUTHOR]

[Display omitted] • Efficient catalytic system for ethanol homologation to biofuel. • Suitable transformation of wine waste bio-ethanol to second generation biofuel. • Boosting the Guerbet reaction: a tandem homogeneous catalytic solution. The catalytic activity of anionic ruthenium complexes toward the transformation of bio-ethanol to 1-butanol and higher alcohols is found to be dependent on the imidazolium counterion. After the identification of a parallel reaction involving the catalyst in hydrogen evolution, conversion and selectivity are impressively boosted by the addition of p-benzoquinones as co-catalysts. The catalytic system avoids the side reaction and led to highly competitive conversions up to 88% (0.2 % mol ruthenium catalyst loading, 1.5 % mol benzoquinone loading). Butanol and higher alcohols are produced in yields up to 85% (overall selectivity 97%) as a mixture of valuable alcohols for advanced biofuel and lubricants applications. The catalytic system can be recycled and the reaction shows comparable efficiency on a real matrix (alcohol from wine production chain wastes) even in the presence of significant amounts of water, thus closing a hypothetic economic circle. A reaction mechanism is proposed for the most promising ruthenium complex working in cooperation with the most efficient co-catalyst: p-benzoquinone. [ABSTRACT FROM AUTHOR]

Alternative fuels have risen in importance and play a vital part in compression ignition engines, therefore the need to reduce reliance on Diesel as a fuel, as well as its economic implications, has arisen as a top priority. Various studies have mostly focused on the usage of alternative fuel to examine if there is a reduction in fuel consumption. To investigate the performance and pollutant emissions of a four-stroke CI engine running on ethanol-Diesel blend of 0%, 5%, 10%, 15%, 20% and 25%. Bioethanol characteristics were assessed using American Society for Testing and Materials (ASTM) standards. The results of the experiments demonstrated that utilizing ethanol-diesel mixed fuels enhanced the engine's power and torque output by a small margin. The aim of the research is to examine the range of options and future prospects for introducing Ethanol-Diesel blends, as well as subsequent alternative fuels in varying percentage ratios, into existing CI engines by diagnosing various aspects such as air-fuel ratio, operating cylinder pressure, ignition timing, and compression ratio that are only related to performance parameters. [ABSTRACT FROM AUTHOR]

S. polyrhiza will be considering as a 2G feedstock, as generating 15–22 g/m2d fresh biomass by improving the quality of sewage. We propose a tractable circular process for pigments, lipid, Nano-catalysts and energy dense substrate (starch) from S. polyrhiza biomass. A ton of S. polyrhiza biomass was responsible for production of 0.8–1.2 kg of R-phycoerythrin, 0.7–0.9 kg of R-phycocyanin, 2.7–4.3 kg of lipids, 5.3–6.1 kg of ZVI, 79.7–80.4 kg of starch. The produced starch was further fermented to yield 38.8–40.8 l of ethanol. The waste generated in each step was utilized to produce 2.23 lakh liter biogas equivalent 8.51 GJ energy. The elimination of residue, reduce ∼79–85% in chemicals and energy usage in starch extraction. The synthesized ZVI efficiently mineralized RV5 wastewater at the rate of 26.29 ± 0.23 kgCODm−3d−1 up to seven cycles. S. polyrhiza reduce ∼240 kgCO 2 -eq for attaining one-ton fresh biomass. Overall findings will the base for starting bio-industries which minimizing the dependence on the terrestrial resources for food, energy and chemicals. [Display omitted] • First study on production of traceable commodity chemicals from S.polyrhiza. • Synthesized ZVI has maximum reduction efficiency of 26.29 ± 0.23 kg COD m−3d−1. • The waste generated was utilized to produce bioethanol and 2.23 lakh liter of biogas. • S. polyrhiza reduce ∼240 kgCO 2 -eq for attaining one-ton fresh biomass. [ABSTRACT FROM AUTHOR]

[Display omitted] • WT + ZSM-5 produces hydrochar peaking at 29.0 MJ/kg HHV and 1.4 enhancement factor. • At 260 °C in a 60 min, hydrochar with a remarkable 76.7 % carbon content was obtained. • At 180 °C in a 15 min WT process achieved an exceptional 89.8 % ethanol selectivity. • At 240 °C in a 60 min WT, outstanding 69.5 % selectivity for levulinic acid was achieved. Creating a sustainable society hinges on efficient chemical and fuel production from renewable cellulosic biomass, necessitating the development of innovative transformation routes from cellulose. In this investigation, we unveil a pioneering chemocatalytic method, utilizing an H-ZSM-5 catalyst within a batch reactor under a nitrogen atmosphere, for the simultaneous one-pot generation of levulinic acid (LA) and/or ethanol during wet torrefaction (WT) of wood cellulose pulp residue (WCPR), yielding high-quality solid fuel. WT parameters include a temperature range of 180 to 260 °C, H 2 O/WCPR = 10, and reaction durations of 15 to 60 min. Optimal conditions for bio-ethanol production are identified at 180 °C and 15 min, achieving an outstanding 89.8 % selectivity with H-ZSM-5 catalyst. Notably, 69.5 % LA formation occurs at 240 °C after 60 min. Hydrochar assessments include higher heating values (HHVs), decarbonization (DC), dehydrogenation (DH), deoxygenation (DO), enhancement factor, carbon enrichment, surface area, pore diameter, weight loss, and yields of solid, carbon, hydrogen, and energy. The highest carbon content of 76.7 % is attained at 260 °C for 60 min, resulting in an HHV of 29.0 MJ/kg, an enhancement factor of 1.44, and carbon enrichment of 1.59, with a sequence of element removal as DO > DH > DC. A proposed reaction pathway elucidates WT of WCPR with the H-ZSM-5 catalyst, emphasizing the direct cellulose conversion into hydroxyacetone and subsequent ethanol generation through C–C cleavage of hydroxyacetone. Through this research approach, both ethanol and LA can be produced efficiently from renewable cellulosic biomass, offering a novel pathway to reduce dependence on fossil resources. [ABSTRACT FROM AUTHOR]

Methanol is an important intermediate in the utilization of natural gas for synthesizing other feedstock chemicals. Typically, chemical approaches for building C-C bonds from methanol require high temperature and pressure. Biological conversion of methanol to longer carbon chain compounds is feasible; however, the natural biological pathways for methanol utilization involve carbon dioxide loss or ATP expenditure. Here we demonstrated a biocatalytic pathway, termed the methanol condensation cycle (MCC), by combining the nonoxidative glycolysis with the ribulose monophosphate pathway to convert methanol to higher-chain alcohols or other acetyl-CoA derivatives using enzymatic reactions in a carbon-conserved and ATP-independent system. We investigated the robustness of MCC and identified operational regions. We confirmed that the pathway forms a catalytic cycle through (13)C-carbon labeling. With a cell-free system, we demonstrated the conversion of methanol to ethanol or n-butanol. The high carbon efficiency and low operating temperature are attractive for transforming natural gas-derived methanol to longer-chain liquid fuels and other chemical derivatives.

Abstract Background A microorganism engineered for non-native tasks may suffer stresses it never met before. Therefore, we examined whether a Kluyveromyces marxianus strain engineered with a carotenoid biosynthesis pathway can serve as an anti-stress chassis for building cell factories. Results Carotenoids, a family of antioxidants, are valuable natural products with high commercial potential. We showed that the free radical removal ability of carotenoids can confer the engineered host with a higher tolerance to ethanol, so that it can produce more bio-ethanol than the wild type. Moreover, we found that this engineered strain has improved tolerance to other toxic effects including furfurals, heavy metals such as arsenate (biomass contaminant) and isobutanol (end product). Furthermore, the enhanced ethanol tolerance of the host can be applied to bioconversion of a natural medicine that needs to use ethanol as the delivery solvent of hydrophobic precursors. The result suggested that the engineered yeast showed enhanced tolerance to ethanol-dissolved hydrophobic 10-deacetylbaccatin III, which is considered a sustainable precursor for paclitaxel (taxol) bioconversion. Conclusions The stress tolerances of the engineered yeast strain showed tolerance to several toxins, so it may serve as a chassis for cell factories to produce target products, and the co-production of carotenoids may make the biorefinary more cost-effective.

Core-shell particles is a type of materials that consist of an inner core structure and an outer shell made from different components. They have been employed as a catalyst due to their unique properties, arising from the combination of the core and shell materials. In addtion, the properties of the core-shell particles can be designed using several suface modification techniques in order to improve the activity and stability of the catalyst. Chemical grafting is a surface modification method that involves the reaction between a metal alkoxide precursor and the surface hydroxyl group of a support. This technique has been reported to be one of the most interesting surface modification techniques that provide a well-dispersed metal oxide on the surface of a support. Micro-emulsion is also considered as one of the simplest and effective methods for the preparation of nano-sized particles with a narrow size distribution, which can be immobilized on the surface of a support. In this work, the impact of preparation methods on the physical and chemical properties of the CuO@ZrO2/FeMgAl-LDO shell@core catalyst and 1,3-butadiene production were investigated. The catalyst samples were characterized using several techniques, including XRD, XRF, BET, NH3-TPD, CO2-TPD, TEM-EDX, and SEM-EDX. The activity of catalyst samples on ethanol conversion was performed in a continuous U-tube fixed-bed reactor at 400 ​°C and atmospheric pressure. It was found that the conversion of ethanol to 1,3-butadiene was a surface sensitive reaction. Therefore, the specific catalyst preparation method was required in order to achieve a high 1,3-butadiene yield. Particularly, in this case, the catalyst that provided the highest yield of 1,3-butadiene was in the form of ZrO2-grafted granular catalyst (CuO@gf-ZrO2/g-FeMgAl-LDO one). Based on the characterization results, the grafted granular core-shell catalyst was the one that had the highest ratio of total base/acid sites.

Renewable plant wastes constitute environmental nuisance. Their conversion by enzymes into bioethanol can be beneficial. We investigated the use of renewable plant waste as substrate for enzyme production and hydrolysis of the plant waste for ethanol production using an indigenous yeast strain. Five yeast strains; MCC-1, MCC-2, MCC-3, MCC-4 and MCC-5 were evaluated for production of sugars, α-amylase, glucoamylase and bioethanol using soluble starch. Phylogenetic analysis using partial sequence of the ITS gene classified MCC-4 as Pichia exigua. Proximate composition of plant wastes - cassava, wild yam, mango seed, udara seed and breadfruit were determined. Results showed total carbohydrate of (83.9%) for cassava flour. The ability of yeast to utilize these substrates and the effect of culture conditions (inoculum, pH, nitrogen source and substrate concentration) were also determined. Cassava pulp flour was the best substrate producing reducing sugar (1.471 ± 0.056mg/mL), α-amylase (0.573 ± 0.019U/mL), glucoamylase (1.605 ± 0.119U/mL), and ethanol (4.440 ± 0.014g/L). Culture conditions revealed optimum for inoculum concentration as (1mL), pH (4), nitrogen source (soya bean, 3g/L) and substrate concentration of (8%). Pichia exigua (MCC-4) a natural yeast strain isolated from the soil has the potential for both enzyme and ethanol production in a single step process. [ABSTRACT FROM AUTHOR]

Moderate Intensity Low Oxygen Diluted (MILD) combustion has been investigated for a long time in order to minimize NOX emission still enhancing thermal efficiencies in the combustion equipment. Many researches about MILD combustion have been recently performed, but studies on MILD combustion of renewable fuel such as ethanol has been very scarce and particularly, specific information on the NOX production in ethanol-air MILD combustion has not been reported yet. In order to satisfy the condition for MILD combustion, internal recirculation is known to be essential in order to entrain the combustion products gas into air and fuel jets of combustion system. In this work, a series of numerical analysis with simplified opposed jet geometry have been done using the OPPDIF in Ansys program. Numerical analysis on how the recirculation ratio (KV) affects NOX emission in the ethanol-air combustion for MILD formation were carried out under the condition of various burnt gas dilution in reactant flow. The results show that the temperature was decreased by the increase of the recirculation ratio and the maximum heat release value became also low by the increase of the recirculation ratio. It was also found that the pyrolysis zone of the heat release was disappeared and the two heat release peaks are merged into one as combustion pattern is changed to MILD combustion mode.

One‐pot direct synthesis of renewable p‐xylene (PX) via Diels‐Alder cycloaddition of completely bio‐based ethanol and 2,5‐dimethylfuran (DMF) was studied comparatively over dealuminated HBeta zeolite and functionalized mesoporous MCM‐41. The sulfonic group‐functionalized MCM‐41 had better catalytic performances. Under the optimized conditions, an ethanol conversion of ∼100 %, 2,5‐DMF conversion of 79 % and PX selectivity of 80 % were obtained over NH3‐Silylated‐MCM‐41‐10 %SO3H catalyst with 0.8 wt % N content, which is much better than HBeta zeolite catalyst. X‐ray diffraction (XRD), thermogravimetric analysis (TGA), 29Si cross‐polarization magic‐angle spinning (CP/MAS) NMR and infared (IR) characterizations showed that sulfonic and silylated groups have been successfully grafted onto MCM‐41. Quantitative 1H MAS NMR with d5‐pyridine adsorption unambiguously demonstrated that silylated MCM‐41‐SO3H with NH3 pre‐treatment has much higher amount and stronger strength of Brönsted acid than zeolite catalyst. This is the vital factor to catalyze the dehydration of ethanol to ethylene and speed up the Diels‐Alder cycloaddition reaction, ultimately increase PX selectivity and reduce much less soft‐coke deposit on MCM‐41‐SO3H (∼4 wt %) than on HBeta zeolite (∼12 wt %). This work demonstrates a simple and economical strategy to further improve the potential for the production of sustainable chemicals from complete biomass. [ABSTRACT FROM AUTHOR]

This paper proposed a methodology to realize the co‐production of bio‐ethanol and bio‐oil from macroalgae. Bio‐ethanol were obtained from three different species of macroalgae (Enteromorpha prolifera, Undaria pinnatifida and Gelidium amansii) by hydrolysis and fermentation. And then the residues after hydrolysis were converted into bio‐oil with high heating value via deoxy‐liquefaction. The yield of reducing sugar and bio‐ethanol from three macroalgae were calculated. The red algae (Gelidium amansii) produced the reducing sugar with largest yield of 320±4.1 mg/g and ethanol with a maximum content of 9.09±0.07 g/L. Besides, the properties and components of the liquid oils have been analyzed and compared with each other. The lower oxygen content (4.47 %, 4.98 % and 4.02 %) and higher heating value (45.06, 44.53 and 45.12 MJ/kg) of the liquid oils were detected respectively. The results indicated that macroalgae had a great potential for co‐production of bio‐ethanol and high‐quality bio‐oil. [ABSTRACT FROM AUTHOR]

• Bio-ethanol production from Scenedesmus obliquus deoiled cake (SO) was performed. • Biomass properties of SO has been examined and evaluated using suitable techniques. • Green catalyst (CBPA, CWH, CCPS, CTGL, K-RAC) were employed for saccharification. • Fermentation by Saccharomyces cerevisiae isolate BY01. • Maximum ethanol yield of 68.32 % at 8.24 g/L was achieved using CTGL green catalyst. Microalgae have been accepted as a potential feedstock for biofuel production due to their high oil content and rapid biomass production. In this study, deoiled Scenedesmus obliquus (SO) was used for evaluating whether deoiled algal biomass residue is potential as an alternative energy resource for bio-ethanol production with different heterogeneous catalysts. The SO biomass was examined for its physiochemical properties and also evaluated using FTIR, XRD, and TGA techniques. The successful hydrolysis of SO was performed employing different eco-friendly bio-based heterogeneous catalysts and hydrolysate thus obtained was then subjected to fermentation using Saccharomyces cerevisiae and was analyzed through HPLC and GC which resulted in the production of bio-ethanol with the highest yield of 68.32 % at 8.24 g/L concentration. [ABSTRACT FROM AUTHOR]

Reducible sugar solution has been produced from waste broken rice by a novel saccharification process using a combination of bio-enzyme (bakhar) and commercial enzyme (α-amylase). The reducible sugar solution thus produced is a promising raw material for the production of bioethanol using the fermentation process. Response surface methodology (RSM) and Artificial neural network-genetic algorithm (ANN-GA) have been used separately to optimize the multivariable process parameters for maximum yield of the total reducing sugar (TRS) in saccharification process. The maximum yield (0.704 g/g) of TRS is predicted by the ANN-GA model at a temperature of 93 °C, saccharification time of 250 min, 6.5 pH and 1.25 mL/kg of enzyme dosages, while the RSM predicts the maximum yield of 0.7025 g/g at a little different process conditions. The fresh experimental validation of the said model predictions by ANN-GA and RSM is found to be satisfactory with the relative mean error of 2.4% and 3.8% and coefficients of determination of 0.997 and 0.996. [ABSTRACT FROM AUTHOR]

This paper discusses the epochal change in the reputation of carbon dioxide, which is now considered as a raw material alternative to fossil C for the synthesis of chemicals, materials and fuels, as opposed to a waste material that must be confined underground. In particular, its use as renewable C is compared to biomass. In this paper, a specific point is discussed: is ethanol (or any fuel) produced via the catalytic conversion of atmospheric CO2 different from the relevant biomass-sourced product(s)? The answer to this question is very important because it ultimately determines whether or not fuels derived from atmospheric CO2 (either e-fuels or solar fuels) have the right to be subsidized in the same way that biofuels are. Conclusions are drawn demonstrating that ethanol derived from atmospheric CO2 deserves the same benefits as bio-ethanol, with the additional advantage that its synthesis can be less pollutant than its production via the fermentation of sugars. The same concept can be applied to any fuel derived from atmospheric CO2.

Abstract The pentose phosphate pathway (PPP) plays an important role in the synthesis of ribonucleotides and aromatic amino acids. During bioethanol production from cellulosic biomass composed mainly of d-glucose and d-xylose, the PPP is also involved in xylose metabolism by engineered Saccharomyces cerevisiae. Although the activities and thermostabilities of the four PPP enzymes (transaldolase: TAL1, transketolase: TKL1, ribose-5-phosphate ketol-isomerase: RKI1 and d-ribulose-5-phosphate 3-epimerase: RPE1) can affect the efficiency of cellulosic ethanol production at high temperatures, little is known about the suitable expression levels of these PPP genes. Here, we overexpressed PPP genes from S. cerevisiae and the thermotolerant yeast Kluyveromyces marxianus either singly or in combination in recombinant yeast strains harboring a mutant of xylose isomerase (XI) and evaluated xylose consumption and ethanol production of these yeast transformants in glucose/xylose mixed media at 36 °C. Among the PPP genes examined, we found that: (1) strains that overexpressed S. cerevisiae TKL1 exhibited the highest rate of xylose consumption relative to strains that overexpressed other PPP genes alone; (2) overexpression of RKI1 and TAL1 derived from K. marxianus with S. cerevisiae TKL1 increased the xylose consumption rate by 1.87-fold at 24 h relative to the control strain (from 0.55 to 1.03 g/L/h); (3) the strains with XI showed higher ethanol yield than strains with xylose reductase and xylitol dehydrogenase and (4) PHO13 disruption did not improve xylose assimilation under the experimental conditions. Together these results indicated that optimization of PPP activity improves xylose metabolism in genetically engineered yeast strains, which could be useful for commercial production of ethanol from cellulosic material.