Bioethanol Yield Research Articles

Combining ability and heterosis of sweet stem sorghum genotypes for bioethanol yield and related traits

Combining ability and heterosis of sweet stem sorghum genotypes for bioethanol yield and related traits

Lignocellulosic Bioethanol Production of Napier Grass Using Trichoderma reesei and Saccharomyces cerevisiae Co-Culture Fermentation

Bioethanol from agricultural waste is an attractive way to turn waste into added value that will solve the problem of food competition and waste management. Napier grass is a highly productive and effective lignocellulosic biomass, which is an important substrate of the second-generation biofuels. In addition, several processes are required in the production of ethanol from lignocellulosic materials; thus, co-culture fermentation can shorten the production process. This experimental research utilizes Trichoderma reesei and Saccharomyces cerevisiae co-culture fermentation in the bioethanol production of Napier grass using simultaneous saccharification and fermentation technology. To improve ethanol yield, Napier grass was pretreated with 3% (w/w) sodium hydroxide. An orthogonal experimental design was employed to optimize the Napier grass content, mixed crude co-culture loading, and incubation time for maximum bioethanol production. The results showed that pretreatment increased cellulose contents from 52.85% to 82%. The optimal fermentation condition was 15 g Napier grass, 15 g mixed crude co-culture, and 7 days incubation time, which maximizes the bioethanol yield of 16.90 g/L. Furthermore, the fermentation was upscaled 20-fold, and experiments were performed with and without supplemented sugar using laboratory-scale optimal fermentation conditions. The novelty of this research lies in the use of a mixed crude co-culture of T. reesei and S. cerevisiae to produce bioethanol from Napier grass with the maximum bioethanol concentration of 25.02 and 33.24 g/L under unadded and added sugar conditions and to reduce operational step and capital costs.

Role of different fermentation methods in the enhancement of bioethanol production – a review

Waste management and manufacture of hygienic affordable energy are two main challenges that our societies face. With the aims of protecting the environment and reducing dependence on petroleum and other conventional energy sources, the development of renewable energy sources has become increasingly important. Ethanol can be produced chemically from petroleum and from biomass or sugar substrates by fermentation. Food waste (FW) can be used as a feedstock to produce ethanol as it is rich in cellulose, hemicelluloses, and starch. However, the price of the essential enzymes used to convert FW to ethanol remains a complication. The on-site production of the necessary enzymes could be a possible solution. The yield of bioethanol depends on the nature of biomass and the fermentation method used. The yield can be improved by slight modifications in fermentation methods. This present study involves the discussion of conversion of organic wastes into bio-ethanol using different fermentation methods. Also, includes the comparative study between organic wastes and fermentation method.

Bioethanol Production Efficiency from Sorghum Waste Biomass

The problem of global warming is still a major issue, alongside shrinking oil reserves. A great alternative to fossil fuels is offered by biofuels, such as bioethanol from lignocellulosic plants. The sorghum biomass can be effectively used in many industrial directions. It is possible to use every part of this plant; the grain can be used for food production and straw can be used for energy purposes, i.e., for bioethanol. The aim of this study was to analyze the possibilities of bioethanol production from five varieties of sorghum biomass, which is a waste product of seed harvesting. The yields of sorghum cultivars in a three-year vegetation period; the amount of cellulose, hemicellulose, and lignin in the biomass of sorghum; and the amount of ethanol obtained per hectare were evaluated. It was observed that the highest average yield for all cultivars, except GK Emese, was found in the second year of the study. The bioethanol yield per hectare from this biomass was the highest for Sweet Caroline and was 9.48 m3∙ha−1. In addition, significant differences were found in the content of lignin and hemicellulose for the varieties tested in all years of the study and for the content of cellulose in the first and third years. The discussed results were confirmed by detailed statistical analyses, including combined matrices of Pearson correlation coefficients (crp) varieties and cluster analysis. In summary, the usefulness of the biomass of the studied sorghum varieties for the production of bioethanol was demonstrated.

Optimization of binary acids pretreatment of corncob biomass for enhanced recovery of cellulose to produce bioethanol

Lignocellulosic agricultural wastes are the most widely utilized resource for bioethanol production due to several advantages. Removal of hemicellulose and lignin is a prerequired step during bioethanol production from lignocellulosic biomass to upgrade cellulose recovery and the substrate porosity for saccharification. Chemical pretreatment of corncob was performed in the current research applying binary acids (H2SO4 + CH3COOH) in different ratios. The attained maximum removal of lignin and hemicellulose were 81.41 ± 2.3% and 85.6 ± 1.8%, respectively, with enhanced cellulose recovery of 93.5 ± 1.3% at the optimum conditions of binary acids concentration (3%, v/v), biomass loading ratio (0.1 g/mL), pretreatment temperature (120 °C) and time (60 min). The SEM, FTIR and XRD results revealed the removal of hemicelluloses and lignin from the corncob biomass by binary acids pretreatment and confirmed a change in the crystallinity index of corncob biomass. Ethanol fermentation was accomplished at 30 °C at 200 rpm for 4 days with the hydrolysates using Saccharomyces cerevisiae and obtained a maximum bioethanol concentration of 24.6 mg/mL. This study demonstrates that binary acids pretreatment is an alternative approach for the pretreatment of lignocellulosic biomass. The optimized process conditions could also increase cellulose recovery and bioethanol yield.

Bioethanol production from Chlorella vulgaris ESP-31 grown in unsterilized swine wastewater

The potential of microalgae to remove nutrients from swine wastewater and accumulate carbohydrates was examined. Chlorella sorokiniana AK-1 and Chlorella vulgaris ESP-31 were grown in 10% unsterilized swine wastewater and obtained a maximum carbohydrate content and productivity of 42.5% and 189 mg L−1d−1, respectively. At 25% wastewater and 25% BG-11 concentration, the maximum carbohydrate productivity and total nitrogen removal efficiency of C. vulgaris ESP-31 were improved to 266 mg L−1d−1 and 54.2%, respectively. Further modifications in light intensity, inoculum size, and harvesting period enhanced the biomass growth, carbohydrate concentration, and total nitrogen assimilation to 3.6 gL−1, 1.8 gL−1, and 92.2%, respectively. Ethanol fermentation of the biomass resulted in bioethanol yield and concentration of 84.2% and 4.2 gL−1, respectively. Overall, unsterilized swine wastewater was demonstrated as a cost-effective nutrient source for microalgal cultivation which further increases the economic feasibility and environmental compatibility of bioethanol production with concomitant swine wastewater treatment.

Role of nanomaterials in enhanced ethanol production through biological methods – Review on operating factors and machine learning applications

Renewable energy sources based on biomass are identified as sustainable solution to balance the carbon footprint and fuel requirements. The characteristics of bioethanol make it an ideal fuel additive due to its eco-friendliness and calorific value. Fermentation technology is used to convert carbohydrate-rich biomass into biofuel, but technical glitches and high costs have been identified as drawbacks. Nanomaterials have contributed significantly to bioethanol synthesis in terms of enhanced surface activity and selectivity. By using nanoparticles, various steps in the production of bio-alcohol can be made more efficient and cheaper. Based on the extensive review carried out, the best bioethanol yield reported were: dolomite at 121 °C (106%), methyl-functionalized cobalt ferrite– silica at 37 °C (126.9%) and calcium alginate at 37 °C (100%). Magnetic iron oxide covered cellulase yielded 60% in the temperature range of 24–96 °C and Silica-immobilized cellulase yielded 32 g/L at 25–60 °C. Methyl-functionalized cobalt ferrite–silica emerged as an efficient nano-bio catalyst as it gives highest ethanol yield at moderate temperature (37 °C) and pressure (1–2 atm). The mechanism of action of the nanoparticles is discussed in this research and the future directions of research are proposed. Machine learning applications for the prediction of bioethanol yield were discussed in detail.

Production and Bioethanol Potentials of Seven Dryland-Developed Grain Sorghum Cultivars in the Relatively Moist Mid-Atlantic Region

ABSTRACT Global demand for bio-based energy is on the rise and so is research on bioenergy feedstock productivity. In this study, seven cultivars of grain sorghums (‘301/41,’ ‘304/5,’ ‘319/8,’ ‘319/22,’ ‘341/10,’ ‘341/120,’ and ‘366/58’) which developed in the drylands of Texas-US were evaluated in the Mid-Atlantic, a relatively wet region. The objective of the study was to evaluate crop response to phosphorus, productivity in the Mid-Atlantic, and its potential for bioethanol production. Seed yield, starch, and element content, stover biomass, forage quality, and whole-plant bioethanol yield were determined. Phosphorus had no effect, and only cultivars were compared. Cultivar showed differences in seed and stover yield, seed quality attributes, and potential bioethanol yield. Cultivar ‘366/58’ produced the greatest seed yield averaged at 4934 kg ha −1 yr −1 while ‘301/41’ and ‘341/10’ produced the least averaged at 2,743 and 2,968 kg ha −1, respectively, Stover yield across years ranged from 6,798 to 13,365 kg ha −1, and the whole plant estimated bioethanol ranged from 3,159 to 5,770 L ha −1. The stover had appreciable forage quality, including a 49 g kg −1 crude protein, sufficient for animal maintenance needs. Up to 96 kg N ha −1 and 211 kg K ha −1 were removed from harvested stover, an issue of concern for crop fertilizer management strategy and sustained production.

Agronomic characterization of Taiwan grass [<i>Cenchrus purpureus</i> (Schumach.) Morrone] and evaluation of its potential to produce bioethanol in the warm sub-humid climate of Mexico

The objective of this study was to evaluate the biomass production, chemical composition, proximate analysis, calorific value and theoretical yield of bioethanol of Taiwan grass under 6 cutting frequencies. The highest production of biomass (33 t DM/ha), cellulose content (41.3%), calorific value (17.5 MJ/kg DM) and potential bioethanol yield (7,936 L/ha) were recorded at a cutting frequency of 180 days. The highest moisture content of the dehydrated samples and ash and crude protein concentrations were observed at a harvest frequency of 30 days with 9.2, 12.1 and 10.5%, respectively. The highest concentrations of extractives were obtained at harvest frequencies of 60 and 120 days (13.9 and 13.7%, respectively), while lignin concentrations were greatest at harvest frequencies of 150 and 180 days (21.1 and 20.9%, respectively). The highest concentration of fixed carbon was observed at a harvest frequency of 90 days (18.5%), while the lowest concentration of volatile matter occurred at a harvest frequency of 30 days. The data indicate that Taiwan grass has significant potential for use to produce bioethanol but assessment of the carbon footprint, life cycle analysis, energy yield (energy produced:energy consumed) of the entire production process is needed to ensure there are positive effects on climate change and greenhouse gas emissions before this process is adopted.

Comparative Studies On Bioethanol Production From Some Starch Based Agricultural Waste Peels

The potential of some starch-based agricultural waste peels (cassava peels, yam peels and potato peels) for bioethanol production was investigated. They were pretreated with physico-chemical agents before being hydrolyzed using cellulase enzymes from the Trichoderma ressei micro-organism. Using co-cultures of Saccharomyces cerevisiae and Pichia stipitis fermentative yeasts, the different hydrolysates were fermented to bioethanol. The bioethanol yields of separate hydrolysis and co-fermentation (SHCF) and simultaneous saccharification and co-fermentation (SSCF) fermentative procedures were evaluated. The maximum bioethanol yields from the fermentation results for cassava peels, yam peels and potato peels were 4.87, 3.78 and 5.31 (% w/v wet biomass) respectively after 72 hours of fermentation. The SSCF method was shown to be more successful since it produced higher bioethanol yields in all of the substrates studied and was quicker. When compared to prior research using different microorganisms, the SSCF technique had a superior fermentation yield using mixed cultures of Trichoderma ressi, Saccharomyces cerevisiae and Pichia stipites.

Comparative Studies On Bioethanol Production From Some Sugar Based Agricultural Wastes

The suitability of some sugar-based agricultural wastes (pineapple peels, banana peels, and plantain peels) were examined for bioethanol production. They were subjected to different physico-chemical pretreatments in order to identify the most effective process and optimize the yield of bioethanol. They were further hydrolyzed by cellulase enzymes from Trichoderma ressei micro-organism isolated from the soil. The various hydrolysates obtained were subsequently fermented to bioethanol using co-cultures of Pichia stipitis and Saccharomyces cerevisiae fermentative yeasts. Separate hydrolysis and co-fermentation (SHCF) and simultaneous saccharification and co-fermentation (SSCF) methods were adopted and their bioethanol yields compared. The fermentation results revealed that the maximum bioethanol yields for pineapple peels, banana peels, and plantain peels were 4.94, 3.85, and 4.57 (% w/v wet biomass) respectively at 72 hours fermentation period. SSCF strategy was observed to be more effective as it gave better bioethanol yields in all the considered substrates and was less time consuming. Mixed cultures of Trichoderma ressi, Pichia stipitis and Saccharomyces cerevisiae through SSCF process resulted to a better fermentation yield when compared with previous studies by other workers.

Bioethanol Production From Rice Husk Through Shcf And Sscf Processing Strategies

In many developing countries, there is great quest for achieving sustainable energy from the conversion of the huge biomass of organic wastes into useful biofuels such as bioethanol. Bioethanol is a renewable clean-liquid biofuel produced by fermentation of sugars or converted starch or cellulose from plant based feedstocks. It is conventionally produced from sugar and starch containing feedstocks. However, these feedstocks are unable to meet the global demand of bioethanol production due to their primary food value and legal pursuits against the legitimacy of their schemes. This study investigated and improved on the feasibility of producing bioethanol from rice husk agro-waste generated from rice production. It was first subjected to different physico-chemical pretreatments in order to optimize the hydrolysate sugar yield and identify the most effective process. It was further hydrolyzed by cellulase enzymes from Trichoderma ressei micro-organism isolated from the soil. Separate hydrolysis and co-fermentation (SHCF) and simultaneous saccharification and co-fermentation (SSCF) strategies/methods were adopted using both hydrometer and Pycnometer measurements. The fermentation results revealed that the maximum bioethanol yield through SHCF and SSCF strategies were 4.64 and 6.45 (% w/v dry biomass) respectively. SSCF strategy was more effective as it gave better bioethanol yield and was less time consuming. This study also shows that rice husk agro-waste of no or little commercial value can be utilized in the production of good quality bioethanol with implications for improved waste management, income and efficient energy generation.

An insight - A statistical investigation of consolidated bioprocessing of Allium ascalonicum leaves to ethanol using Hangateiclostridium thermocellum KSMK1203 and synthetic consortium

Bioethanol can be produced by cellulolytic and ethanogenic bacterial species could efficiently degrade lignocelluloses and have potential for biofuels production through consolidated bioprocessing (CBP). In this study, on-site cellulase production followed by saccharification and fermentation of pre-treated Allium ascalonicum leaves to bioethanol in a single reactor using Hangateiclostridium thermocellum KSMK1203 and consortium of Cellulomonas fimi MTCC 24 and Zymomonas mobilis MTCC 92. A. ascalonicum leaf pre-treatment with different alkalis and different pre-treatment conditions such as alkali dosage and time for proficient removal of hemicellulose and cellulose recovery was optimized using RSM method with the maximum hemicellulose removal of 85.25%. The essential medium components were screened through PBD and further optimized using RSM method for H. thermocellum KSMK1203 and the consortium for maximized bioethanol yield. Hence, this study proposed that wild-type H. thermocellum KSMK1203 strain and consortium could be used for cellulase secretion and simultaneous bioethanol conversion.

Implementation of graphitic carbon nitride nanomaterials and laser irradiation for increasing bioethanol production from potato processing wastes.

Agricultural and agro-industrial wastes (e.g., potato peel waste) are causing severe environmental problems. The processes of pretreatment, saccharification, and fermentation are the major obstacles in bioethanol production from wastes and must be overcome by efficient novel techniques. The effect of exposing the fungi (yeast) Saccharomyces cerevisiae to laser source with the addition of graphitic carbon nitride nanosheets (g-C3N4) with different concentrations on bioethanol production was investigated through the implementation of a batch anaerobic system and using potato peel waste (PPW). Dichromate test was implemented as quantitative analysis for quantification of the bioethanol yield. The benefits of this test were the appearance of green color indicating the identification of ethanol (C2H5OH) by bare eye and the ease to calculate the bioethanol yield through UV-visible spectrophotometry. The control sample (0.0ppm of g-C3N4) showed only a 4% yield of bioethanol; however, by adding 150ppm to PPW medium, 22.61% of ethanol was produced. Besides, laser irradiations (blue and red) as influencing parameters were studied with and without the addition of g-C3N4 nanomaterials aiming to increase the bioethanol. It was determined that the laser irradiation can trigger the bioethanol production (in case of red: 13.13% and in case of blue: 16.14% yields, respectively) compared to the control sample (in absence of g-C3N4). However, by adding different concentrations of g-C3N4 nanomaterials from 5 to 150ppm, the bioethanol yield was increased as follows: in case of red: 56.11% and, in case of blue: 56.77%, respectively. It was found that using fungi and exposing it to the blue laser diode source having a wavelength of 450nm and a power of 250 mW for a duration of 30min with the addition of 150mg L-1 of g-C3N4 nanomaterials delivered the highest bioethanol yield from PPW.

Insights into cell robustness against lignocellulosic inhibitors and insoluble solids in bioethanol production processes

Increasing yeast robustness against lignocellulosic-derived inhibitors and insoluble solids in bioethanol production is essential for the transition to a bio-based economy. This work evaluates the effect exerted by insoluble solids on yeast tolerance to inhibitory compounds, which is crucial in high gravity processes. Adaptive laboratory evolution (ALE) was applied on a xylose-fermenting Saccharomyces cerevisiae strain to simultaneously increase the tolerance to lignocellulosic inhibitors and insoluble solids. The evolved strain gave rise to a fivefold increase in bioethanol yield in fermentation experiments with high concentration of inhibitors and 10% (w/v) of water insoluble solids. This strain also produced 5% (P > 0.01) more ethanol than the parental in simultaneous saccharification and fermentation of steam-exploded wheat straw, mainly due to an increased xylose consumption. In response to the stress conditions (solids and inhibitors) imposed in ALE, cells induced the expression of genes related to cell wall integrity (SRL1, CWP2, WSC2 and WSC4) and general stress response (e.g., CDC5, DUN1, CTT1, GRE1), simultaneously repressing genes related to protein synthesis and iron transport and homeostasis (e.g., FTR1, ARN1, FRE1), ultimately leading to the improved phenotype. These results contribute towards understanding molecular mechanisms that cells might use to convert lignocellulosic substrates effectively.

ТЕХНОЛОГИЯ И ОБОРУДОВАНИЕ ПЕРЕРАБОТКИ АКТИВИРОВАННЫХ СЕЛЬСКОХОЗЯЙСТВЕННЫХ РАСТИТЕЛЬНЫХ ОТХОДОВ В БИОЭТАНОЛ

The article is devoted to the development of technology and equipment for the production of bioethanol from agricultural plant waste, activated by the steam explosion method. The value and novelty of research lies in obtaining new data on the effective acidic and enzymatic hydrolysis of activated raw materials, and developing a technology for the conversion of plant raw materials into bioethanol. The studies were carried out on the basis of the Department of Wood Materials Processing of Kazan National Research Technological University (Republic of Tatarstan, Kazan). A pilot plant for the production of bioethanol and the principle of its operation are presented. Pine wood waste and wheat straw (collected in Kukmor region of the Republic of Tatarstan in the period August-September 2021) were used as raw materials. Steam-explosive activation of raw materials was carried out at temperatures of 165 ⁰C and 210 ⁰C for 5 minutes. Acid hydrolysis parameters: H2SO4 concentration - 0.5% and 1.5%, hydromodule 1:15, hydrolysis temperature - 187⁰C, hydrolysis duration - 5 hours. Enzymatic hydrolysis parameters: preparation - Cellulox-A (OOO PO Sibbiopharm, Russia) - 6 and 12 g/kg of raw material, hydrolysis temperature - 45 ⁰C, substrate pH 4.7 (acetate buffer), raw material concentration in the substrate 33 g/l, the duration of hydrolysis is 72 h. Alcoholic fermentation of hydrolysates was carried out at 32-34⁰C using Saccharomyces cerevisiae yeast, fermentation duration 7 h, yeast concentration 25 g/l. The bioethanol yield in % of reducing substances was recalculated after determining the mass yield. It is concluded that the vapor-explosive activation of pine wood at a temperature of 210 ºC makes it possible to obtain by acid hydrolysis and anaerobic fermentation of reducing substances up to 0.26 kg (0.33 l) of ethanol from 1 kg of activated raw materials, and activation of wheat straw at the same temperature allows obtaining up to 0.172 kg (0.218 l) ethanol with 1 kg of activated straw

Integrating mild chemical pretreatments with endogenous protein supplement for complete biomass saccharification to maximize bioethanol production by enhancing cellulases adsorption in novel bioenergy Amaranthus

Amaranthus is a fast-growing perennial plant containing large amounts of extractable green proteins and lignocellulose residues. However, it remains to explore optimal Amaranthus biomass process technology for biofuel production. In this study, we examined that mild alkali and acid pretreatments (1% NaOH, 2% H2SO4) were sufficient for near-complete biomass enzymatic saccharification, while 8% Amaranthus endogenous proteins were supplemented into the enzymatic hydrolyses. By performing classic yeast fermentation with all carbon sources from directly-extractable sugars and starch and lignocellulose enzymatic hydrolysis, this work achieved the bioethanol yield up to 23.5% (% dry matter). Notably, with respect to extremely high yield of Amaranthus straw, the maximum bioethanol yield was estimated at 14.46 t/ha/year, which was much higher than those of other major bioenergy crops as previously reported. Furthermore, this work proposed a hypothetic model to elucidate how the complete biomass saccharification was achieved to maximize bioethanol production at large scale, based on the effective wall polymer extraction and distinct lignocellulose feature modification for remarkably enhanced biomass porosity and cellulases adsorption. Hence, this work has demonstrated that Amaranthus could be applied as a novel and leading bioenergy crop, providing a powerful strategy for optimal biomass processing towards high bioethanol production.

Research on the potential of some sweet sorghum genotypes as bioethanol source underMediterranean conditions

Sweet sorghum (Sorghum bicolor var. saccharatum (L.) Mohlenbr.) is a variety of sorghum developed for the harvest of sweet juice, rather than grain. It has been identified as a potential ethanol feedstock crop for rainfed areas in different parts of the world. It is a promising source of bioenergy due to its high biomass, drought tolerance and low input. This study was conducted to determine the potential of bioethanol production from different sweet sorghum varieties under the Çukurova conditions with a Mediterranean climate. Experiments were conducted over two years in 2016 and 2017 on the experimental fields of the Eastern Mediterranean Agricultural Research Institute in Adana province between June and October in randomized blocks design with four replications. Harvest was performed at the dough stage of panicle grains. Based on two-year data, an average of days to harvest values of the varieties varied between 98.6 and 134.4 days, plant height between 233.2 and 429.3 cm, stalk diameters between 22.26 and 26.55 mm, stalk yields between 69.0 and 182.6 t ha-1, juice yields between 22.98 and 62.74 m3 ha-1, juice recoveries between 26.79% and 39.94%, brix values between 12.55% and 20.0% and theoretical bioethanol yields between 2020 and 5302 L ha-1. Grass1, M81E, Roma, Theis, UNL Hybrid#3 and No91 genotypes had stalk yields over 150 t ha-1 and bioethanol yields over 4500 L ha-1, thus they were superior to the other varieties in stalk and bioethanol yields. Present findings revealed that the Çukurova region was quite suitable for maximum bioethanol production from sweet sorghum.

Sequential fermentation of organosolv pretreated corn stover for improved cellulose hydrolysis and bioethanol yield

In this study, organosolv pretreatment of corn stover using 40% acetic acid was investigated for its amenability for enzymatic saccharification and bioethanol production. The pretreated corn stover resulted in 63.4±1.7% solids, 46.4±2.5% hemicellulose and 53.7±2.1% cellulose recoveries with 84.6% delignification. The reducing sugars of 0.107g/gds (107/Kg) released during pretreatment can be fermented to produce 0.125ml/gds (125ml/Kg) bioethanol. The saccharification of pretreated biomass under optimized conditions released 0.395g/gds reducing sugars, which upon subsequent fermentation by Saccharomyces cerevisiae and Pachysolen tannophilus produced 0.112g/gds (140ml/Kg) ethanol, with 66.54% fermentation efficiency and 33.9% ethanol yield (YPS), under separate hydrolysis and fermentation (SHF) conditions. The net price for the bioconversion of 1Kg corn stover for bioethanol (265 ml) production was calculated to be Rs. 144.3/L of ethanol. This price is high being calculated on laboratory scale (1Kg) and will decrease substantially upon upscaling.

Effect of hydrogen peroxide acetic acid pretreatment on kapok (ceiba pentandra) fruit peel waste for bioethanol production using separated hydrolysis and fermentation methods

The increase in the world's population has an impact on the increasing demand for fuel energy. With the increasing need for fuel, it causes the depletion of fossil fuel sources. For this reason, the search for alternative energy sources for fuel must be developed so that it can be applied for mass use, one of which is bioethanol. Bioethanol is a renewable energy source that has the potential to be developed in Indonesia. Bioethanol is ethanol from the fermentation of sugar, starchpatian or lignocellulosic biomass. This study examines the effect of hydrogen peroxide acetic acid (HPAC) pretreatment of kapok fruit peel waste on the cellulose, hemicellulose, and lignin content produced, examines the effect of fermentation pH on the levels of bioethanol produced, and examines the effect of fermentation time on the levels of bioethanol produced. In the research of bioethanol production, the variables used were pretreatment of raw materials, pH of fermentation (4, 4.5, 5), fermentation time (3, 5, 7 days). The results showed that the pretreatment of HPAC was able to remove 90% of the lignin content in kapok fruit peel waste, while the optimum pH and optimum time for fermentation were obtained at pH 4.5 and day 5 with the content of bioethanol 8.268% and the highest yield of bioethanol is 8.78%.