Search

AbstractPervaporation separation of isopropanol–butanol–ethanol (IBE) aqueous mixture was carried out using polydimethylsiloxane (PMDS) membranes containing 5, 10, and 15 wt.% of nanosized SiO2. PDMS/SiO2 membranes prepared by solution-casting technique were characterized by Fourier transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA), and field emission scanning electron microscopy (FESEM). Sorption experiments were performed at 30 °C, 40 °C, and 50 °C, and the interaction parameters between the pure components and the membrane were calculated. Further, the activity coefficients, excess Gibbs energies, and binary interaction parameters of organic-water binary systems at different temperatures were estimated using the UNIFAC method. A single-component permeation through pristine PDMS and nanocomposite PDMS membranes, as well as the pervaporation separation performance of PDMS-based membranes at different temperatures for a model IBE mixture with a concentration of 20 g·L−1, were investigated. The pervaporation results showed that the highest butanol permeability (15514 Barrer) and selectivity (102.6) values were obtained for 5 wt.% and 15 wt.% SiO2-filled PDMS membranes at 30 °C, respectively. [ABSTRACT FROM AUTHOR]

In this study, an upflow anaerobic packed-bed reactor (UAPB) produced biobutanol from the main byproduct of biodiesel plants, commonly known as glycerol. Currently, butanol production is mostly limited to pure cultures and sterilized feedstocks. Using glycerol wastes from biodiesel production demands a new paradigm because sterilization is not economically feasible for the elevated amount of glycerol generated by the biodiesel industry. Different microbial consortia were evaluated as inoculum sources to convert glycerol to butanol. In the first stage, operations were carried out with an average organic loading rate (OLR) of 13 g COD L−1 d−1. Kefir grains, sucrose auto-fermentation consortium, and heat-treated anaerobic sludge produced 16.7, 48.5, and 12.8 mg of butanol per gram of chemical oxygen demand (COD), respectively. Besides butanol production, a significant amount of ethanol (241.5 mg g−1 COD), acetate (30.3 mg g−1 COD), and butyrate (183.4 mg g−1 COD) were generated with glycerol processed by sucrose auto-fermentation consortium. In the second stage, the organic loading rates of 6.5, 13.0, and 26.0 g COD L−1 d−1 were applied to the UAPB reactor inoculated with sucrose auto-fermentation consortium. The OLR of 13.0 g COD L−1 d−1 yielded the highest production of butanol (41.5 mg g−1 COD) and generated other valuable co-products such as butyrate (246.1 mg g−1 COD), acetate (37.3 mg g−1 COD), and propionate (19.6 mg g−1 COD). [ABSTRACT FROM AUTHOR]

Butanol as a biofuel, can be produced by ABE (acetone-butanol-ethanol) fermentation. Pervaporation is a promising process, especially for the separation of biofuels from aqueous mixtures such as ABE mixtures which consists of 3:6:1 ratio of ABE solvents and water around 97%. In this study, ionic liquid-based membranes were developed for the recovery of butanol from aqueous mixtures. The active layer providing the selectivity was formed by using polydimethylsiloxane (PDMS) and 1-butyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide ([bmim][Tf2N]) ionic liquid (IL). Porous polyvinylidenefluoride (PVDF) and polytetrafluoroethylene (PTFE) films were used as the support layers. Two different types of membranes were prepared, in which IL was mixed into PDMS and cast as a thin film on the support layer, and IL was impregnated into the pores of the support layers. The effects of feed concentration and temperature on separation performance were investigated. In addition, the membranes were prepared with and without IL, and the effect of IL on membrane performance was investigated. In general, an increase in flux and selectivity values ​​was observed with the addition of IL in PDMS. Butanol selectivities in pervaporation experiments with different process parameters were found between 24.7 and 61.3 when PTFE support layer was used and between 22.5 and 48.6 when PVDF support layer was used. Especially with the use of IL in the membrane, the fluxes increased 2.5-5 times, resulting in a significant increase in fluxes. As a result, it has been shown that PDMS+IL/PVDF and PDMS+IL/PTFE membranes can be used for effective butanol recovery by pervaporation. [ABSTRACT FROM AUTHOR]

Deep eutectic solvent-assisted delignification followed by a one-pot process of saccharification and extractive biobutanol production via ABE fermentation was achieved with sorghum straw biomass (SSB). Six protic natural deep eutectic solvents (PNADES) were synthesized and applied for the delignification of SSB. The eutectic mixture formed with choline chloride and citric acid was observed to have a significantly higher degree of lignin (90% w/w) and xylan (83% w/w) removal which was confirmed by observation under a scanning electron microscope. The cellulose-rich biomass was holistically exposed to enzymatic hydrolysis (Cellulase CTEC 21) and inoculated with Clostridium acetobutylicum (11,274) to facilitate biobutanol production. Response surface methodology optimization of influential parameters like inoculum size (9.75% v/v), biomass feed (24.5 mg/ml), and incubation time (122.5 h) has resulted in effective biobutanol productivity of (0.284 g L−1 h−1). Further, scale-up of the process carried out in a 2-L stirred tank bioreactor operated under anaerobic conditions resulted in a higher degree sugar utilization rate of 80% (w/w) enabling better butanol recovery (0.36 g L−1 h−1). This study successfully demonstrated sustainable operation conditions for the effective large-scale production of biobutanol through delignification followed by saccharification and extractive bioconversion of sorghum straw biomass. [ABSTRACT FROM AUTHOR]

In this study, we investigated the metabolic behavior of the engineered Clostridium acetobutylicum ATCC 824 (pCD07239) strain during the acidogenic phase under varying glucose concentrations and pH conditions. Unlike the wild-type C. acetobutylicum ATCC 824, the engineered strain exhibited negligible butyrate production and simultaneous butanol production during the acidogenic phase under limited glucose condition of 25 g/L. Specifically, batch fermentations of the engineered strain with 25 g/L glucose at a pH of around 5.0 (initially uncontrolled) demonstrated butanol production of 2.99 g/L, while butyrate remained below 0.30 g/L. Separately, in batch fermentations at pH 6.0 with 90 g/L glucose, acetate production nearly doubled compared to fermentations at pH 5.0 with the same glucose concentrations, reaching a maximum concentration of 11.43 g/L, while butyrate production remained relatively low at 4.04 g/L. Under these pH 6.0 and 90 g/L glucose conditions, butanol production reached 9.86 g/L. These findings indicate that C. acetobutylicum ATCC 824 (pCD07239) maintained low butyrate production, even under conditions favoring acidogenesis, and consistently produced butanol. Additionally, the negligible production of acetone at pH 6.0 further indicates that the traditional phase transition was not prominent, suggesting altered regulation mechanisms in the engineered strain. These findings highlight C. acetobutylicum ATCC 824 (pCD07239) strain's unique metabolic profile and its potential for efficient biobutanol production under diverse conditions. [ABSTRACT FROM AUTHOR]

The present study aims to evaluate the use of cranberry bush fruit pomace (CBFP) (Viburnum opulus L.), which has recently become popular raw material, as a substrate in the presence of a reducing agent to increase biobutanol production by Clostridium beijerinckii DSMZ 6422. For this purpose, some factors were optimized, including the pretreatment, initial concentration of CBFP (5–20%), different types of reducing agents (ascorbic acid, L-cysteine, sodium dithionite and sodium sulfite), different concentrations of sodium dithionite (2.5–15 mM), inoculum concentration (5%, 10%, and 20%), and fermentation time (24–96 h). The maximum biobutanol, total ABE, biobutanol yield, and biobutanol productivity were 9.45 g/L, 12.08 g/L, 0.21 g/g, and 0.13 g/L/h in the medium containing enzymatically hydrolyzed 10% CBFP, 10 mM sodium dithionite, and 20% inoculum at the end of 72 h, respectively. These findings demonstrate that CBFP can be considered as a sustainable, economical, and viable substrate on biobutanol production for the first time in the literature. [ABSTRACT FROM AUTHOR]

The biobutanol‐based biofuel fermentation is hindered by the challenge of inadequate fermentation broth concentration and the azeotropic systems of water. The application of eucalyptus oil in diesel fuel makes it a promising extractant for biobutanol extraction and dehydration, thus resulting in product recovery and the development of fuel blend technology. Eucalyptus oil‐derived 1,8‐cineole was applied to acetone‐butanol‐ethanol (ABE) and isobutanol systems to enhance the butanol recovery and dehydration. The recovery of n‐butanol and isobutanol reached 92% and 95%, respectively, while the water removal in a 2% butanol system exceeded 99%. These results demonstrated that 1,8‐cineole exhibited a high selectivity toward butanol, thus providing a robust theoretical foundation for the fermentation‐based biofuel recovery and the elimination of azeotropic systems. The introduction of high‐density diesel‐fuel‐like eucalyptus oil into low‐energy‐density biobutanol will increase the energy density of fermentation‐based alcohols, yielding linear and cyclic biofuel blends. [ABSTRACT FROM AUTHOR]

The current study proposes RBBR biosorption by Clostridium beijerinckii DSMZ 6422 biomass remaining after biobutanol production from pumpkin peel (PP) by a zero-waste approach. Efficient biobutanol production was achieved by investigating initial PP concentrations (5–20% without or with enzymatic hydrolysis) and fermentation time. According to this, the highest concentrations of biobutanol and total ABE were obtained as 4.87 g/L and 8.13 g/L in the presence of 10% PP without enzymatic hydrolysis at 96 h. Furthermore, based on the zero-waste approach, C. beijerinckii DSMZ 6422 biomass obtained after biofuel production was used as a biosorbent for the removal of RBBR dye. Response surface methodology (RSM), commonly utilized for the experimental design, was used to specify the optimized biosorption conditions of RBBR, including initial dye concentration (50–200 mg/L), initial pH (2–6), biosorbent concentration (1–3 g/L), and contact time (0–240 min). The highest biosorption under optimized conditions with RSM was 98% in the presence of 194.36 mg/L RBBR and 2.65 g/L biosorbent at pH 2 and 15 min. This is the first report in the literature about the biosorption of RBBR dye by anaerobic C. beijerinckii biomass after the biobutanol production process. This study also shows the efficient usage of agricultural and microbial wastes in different areas based on zero-waste applications. [ABSTRACT FROM AUTHOR]

Copyright of China Brewing is the property of China Brewing Editorial Office 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.)

The fermentation route for producing biobutanol from renewable plant biomass was used extensively during the last century. The key factors affecting performance in the standard batch industrial fermentation process are highlighted. Four species of Clostridium were utilized for the industrial production of solvents, and although they share many features in common, they also exhibit significant differences. The salient features of the existing industrial species and strains are reviewed. These include their suitability for the type of process and fermentation substrate used. The strains are also assessed with respect to their potential for future applications.

The fermentation route for producing biobutanol from renewable plant biomass was used extensively during the last century. The key factors affecting performance in the standard batch industrial fermentation process are highlighted. Four species of Clostridium were utilized for the industrial production of solvents, and although they share many features in common, they also exhibit significant differences. The salient features of the existing industrial species and strains are reviewed. These include their suitability for the type of process and fermentation substrate used. The strains are also assessed with respect to their potential for future applications. [ABSTRACT FROM AUTHOR]

In this study, Micractinium sp. was randomly mutated by UV mutagenesis, and the contributions of Micractinium strains to the total biofuel and pigment production were investigated by adding abscisic and salicylic acid and examining the antioxidant activities of the strains to determine how they responded to these environmental and genetic alterations. As a result, compared with the control, the M-25 strain with 8 mg/L salicylic acid exhibited an increase of 54% in biodiesel production and 23% in biobutanol production, providing the maximum lipid percentage of 40%, whereas the M-7 strain and 0.2 mg/L abscisic acid showed an increase of 77% in biobutanol production while providing the highest carbohydrate percentage of 23%. The maximum total biofuel production was 139% for M-25 at 8 mg/L salicylic acid, and the highest amount of carotenoids (10.8 mg/g) was found to be approximately twice as high in the M-25 strain at 0.2 mg/L abscisic acid compared with the control. [ABSTRACT FROM AUTHOR]

This study aims the third generation biobutanol production in P2 medium supplemented D. salina biomass mixotrophically cultivated with marble waste (MW). The wastes derived from the marble industry contain approximately 90% of carbon-rich compounds. Microalgal growth in mixotrophic conditions was optimized in the 0.4-2 g/L of MW concentration range. The highest microalgal concentration was obtained as 0.481 g/L in the presence of 1 g/L MW. Furthermore, some important parameters for the production of biobutanol, such as microalgal cultivation conditions, initial mixotrophic microalgal biomass loading (50-300 g/L), and fermentation time (24-96 h) were optimized. The highest biobutanol, total ABE, biobutanol yield and productivity were determined as 11.88 g/L, 13.89 g/L, 0.331 g/g and 0.165 g/L/h at the end of 72 h in P2 medium including 60 g/L glucose and 200 g/L microalgal biomass cultivated in 1 g/L MW, respectively. The results show that D. salina is a suitable raw material for supporting Clostridium beijerinckii DSMZ 6422 cells on biobutanol production. To the best of our knowledge, this is the first study on the use of MW which is a promising feedstock on the mixotrophic cultivation of D. salina for biobutanol production. [ABSTRACT FROM AUTHOR]

The selective oxidation of biobutanol to prepare butyric acid is an important conversion process, but the preparation of low-temperature and efficient catalysts for butanol oxidation is currently a bottleneck problem. In this work, we prepared Pt-TiO2 catalysts with different Pt particle sizes using a simple one-step hydrothermal/solvothermal method. Transmission electron microscopy and X-ray diffraction results showed that the average size of the Pt particles ranged from 1.1 nm to 8.7 nm. Among them, Pt-TiO2 with an average particle size of 3.6 nm exhibited the best catalytic performance for biobutanol. It was capable of almost completely converting butanol, even at room temperature (30 °C), with a 98.9% biobutanol conversion, 98.4% butyric acid selectivity, and a turnover frequency (TOF) of 36 h−1. Increasing the reaction temperature to 80 and 90 °C, the corresponding TOFs increased rapidly to 355 and 619 h−1. The relationship between the electronic structure of Pt and its oxidative performance suggests that the synergistic effect of the dual sites, Pt0 and Pt2+, could be the primary factor contributing to its elevated reactivity. [ABSTRACT FROM AUTHOR]

To facilitate depolymerization of cellulose into fermentable sugars, a novel deep eutectic solvent (DES)–mediated Fenton-like system was developed for efficient removal of hemicellulose and lignin components from lignocellulosic biomass. Water hyacinth (WH) was treated with the newly synthesized DES (choline chloride-ethylene glycol-FeCl3; ChCl-EG-FeCl3) at 140 °C for 2 h and then subjected to treatment with 32 mL 30 wt% H2O2 (Fe3+: H2O2 = 1:50 mol·mol–1) for 1 h in a Fenton-like reaction system (DES/H2O2). Hydrolysate containing 28 g·L–1 glucose was obtained, which was 19.6- and 1.6-fold of raw WH and WH pretreated by DES, respectively. The DES/H2O2-WH hydrolysate was further evaluated for butanol fermentation; no significant inhibition was observed on butanol production, giving butanol titer of 8.3 g·L–1, along with a yield of 0.18 g·g–1 glucose and a productivity of 0.12 g·L–1·h–1. Remarkably, DES could be recovered and recycled for five consecutive batches. [ABSTRACT FROM AUTHOR]

Butanol is a promising alternative to fossil-derived fuels. Clostridium genus bacteria are known for their ability to produce butanol as one of the metabolites, however, at the moment this solution is not economically viable. To solve it, the process of butanol production should be optimized. While ABE fermentation has been extensively studied, information about the optimal growth conditions for specific microorganisms often differs from one study to another. Therefore, this study aims to search for optimal growth conditions in sealed serum bottle tests for three widely used strains in ABE fermentation. In this study effects of temperature, pH, and agitation were tested on Clostridium acetobutylicum, Clostridium beijerinckii, and Clostridium saccharoperbutylacetonicum. The optimal temperature for C. beijerinckii growth and butanol production was 32 °C, the optimal agitation speed for growth was 0 rpm, but for butanol production, it was 200 rpm. For C. saccharoperbutylacetonicum growth and butanol production pH 7.5, 30 °C temperature and an agitation rate of 100 rpm were optimal, however, this effect was slight. For C. acetobutylicum cultivation optimal temperature, pH, and agitation rate were respectively 37 °C, 6.5, and 200 rpm.

In this study, an upflow anaerobic packed-bed reactor (UAPB) produced biobutanol from the main byproduct of biodiesel plants, commonly known as glycerol. Currently, butanol production is mostly limited to pure cultures and sterilized feedstocks. Using glycerol wastes from biodiesel production demands a new paradigm because sterilization is not economically feasible for the elevated amount of glycerol generated by the biodiesel industry. Different microbial consortia were evaluated as inoculum sources to convert glycerol to butanol. In the first stage, operations were carried out with an average organic loading rate (OLR) of 13 g COD L−1 d−1. Kefir grains, sucrose auto-fermentation consortium, and heat-treated anaerobic sludge produced 16.7, 48.5, and 12.8 mg of butanol per gram of chemical oxygen demand (COD), respectively. Besides butanol production, a significant amount of ethanol (241.5 mg g−1 COD), acetate (30.3 mg g−1 COD), and butyrate (183.4 mg g−1 COD) were generated with glycerol processed by sucrose auto-fermentation consortium. In the second stage, the organic loading rates of 6.5, 13.0, and 26.0 g COD L−1 d−1 were applied to the UAPB reactor inoculated with sucrose auto-fermentation consortium. The OLR of 13.0 g COD L−1 d−1 yielded the highest production of butanol (41.5 mg g−1 COD) and generated other valuable co-products such as butyrate (246.1 mg g−1 COD), acetate (37.3 mg g−1 COD), and propionate (19.6 mg g−1 COD).

The study aims to optimize the medium composition for biobutanol production using a Palm Kernel Cake (PKC) hydrolysate by Clostridium saccharoperbutylacetonicum N1-4. Various nutrient factors affecting biobutanol production were screened using the Plackett-Burman design. These factors included: NH4NO3, KH2PO4, K2HPO4, MgSO4.7H2O, MnSO4.7H2O, FeSO4.7H2O, yeast extract, cysteine, PABA, biotin, and thiamin. The results were analyzed by an analysis of variance (ANOVA), which showed that cysteine (P=0.008), NH4NO3 (P=0.011) dan yeast extract (P=0.036) had significant effects on biobutanol production. The established model from the ANOVA analysis had a significant value of Pmodel>F = 0.0299 with an F-value of 32.82 which explains that the factors can explain in detail the variation in the data about the average and the interpretation is true with an R2 value of 0.993. The estimated maximum biobutanol production was 10.56 g/L, whereas the optimized medium produced 15.49 g/L of biobutanol. Process optimizations with optimum concentration of cysteine, NH4NO3, and yeast extract have produced 21.33 g/L biobutanol which is a 37.7% improvement from the non-optimized medium. The findings show that PKC hydrolysate with the addition of optimal concentrations of the three types of medium namely, cysteine (0.15 g/L), NH4NO3 (0.50 g/L), and yeast extract (1.5 g/L) during ABE fermentation, yielded a maximum biobutanol concentration of 21.33 g/L. Therefore, the results of this study provide good indications for promoting PKC hydrolysate as a new source of novel substrates with great potential in producing high biobutanol through ABE fermentation by C. saccharoperbutylacetonicum N1-4. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Petroleum Research & Studies is the property of Republic of Iraq Ministry of Higher Education & Scientific Research (MOHESR) 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.)

Biobutanol stands out as an advanced renewable biofuel, yet its production through fermentation yields a low butanol concentration, necessitating expensive and energy-intensive separation methods, particularly by distillation. Alternative approaches, including adsorptive separation, have emerged, with the 2-column zeolite-based process showing promise. This study employed Aspen Plus for simulating adsorptive separation, utilized Pinch technology for heat integration, and analyzed various alternatives using the life cycle assessment (LCA) approach. Compared to the base case, which relied on our previously acquired experimental data and further purification through atmospheric distillation, the adoption of indirect heating/cooling adsorption reduced heating energy demand by 59.5%. Additionally, cooling energy usage was increased notably by 68.9%, and chilling prerequisites were eliminated. The implementation of Pinch technology further reduced heating and cooling energy requirements by approximately 36%. Multi-pressure distillation was also explored, revealing its potential to reduce heating energy consumption by 46.6%, accompanied by a modest 6.2% increase in cooling energy demand. A gate-to-gate LCA framework was used to evaluate the environmental impacts. The results showed that the combination of indirect heating/cooling adsorption, multi-pressure distillation, and energy-efficient practices resulted in over a 98% reduction in damages related to human health, ecosystem well-being, and resource depletion compared to the base case. Prioritization of key performance indicators revealed that human health had the most significant influence, with prominent midpoint effects attributed to human toxicity and global warming. This study underscores the pivotal role of energy targeting in curtailing energy consumption and enhancing the sustainability of adsorptive biobutanol separation. [ABSTRACT FROM AUTHOR]

Cassava (Manihot esculenta Crantz) has garnered global attention due to its importance as a crucial raw material for ethanol and other derivative production. Nonetheless, its agroindustry generates a substantial amount of residues. We examined the potential utilization of co–products from both agricultural and industrial sectors concerning starch extraction processes. A total of 319 million tons of fresh cassava roots are globally produced, yielding up to 55% of agricultural co–products during harvesting. For every ton of starch extracted, 2.5 tons of bagasse, along with 100 to 300 kg of peel per ton of fresh processed cassava, and 17.4 m3 of residual liquid tributaries are generated. Consequently, both solid agricultural biomass and solid/liquid residues could be directed towards cogenerating bioenergy such as bioethanol, biobutanol, biodiesel, bio–oil, charcoal, and other bioproducts. In conclusion, the conversion of cassava agroindustrial co–products into food and non–food products with high added value could be promoted, thus fostering a circular economy to enhance profitability, sustainability, and crop promotion. [ABSTRACT FROM AUTHOR]

Rapid global urbanisation emphasises the necessity to explore sustainable energy resources to fulfill escalating energy demands. Biobutanol emerges as a promising biofuel due to heightened energy density and molecular similarity to petrol. Microalgae, rich in carbohydrates, offer a potential glucose source for biobutanol fermentation. The current study shows that varying CO 2 concentrations affect carbohydrate content in the biomass of P. kessleri bh-2 and Scenedesmus sp.k-7. The introduction of 1% CO 2 significantly improved carbohydrate productivity, reaching 74.5% for P. kessleri bh-2 and 71.0% for Scenedesmus sp.k-7. Enzymatic hydrolysis was found to be most effective for ABE fermentation, with optimal results obtained at enzyme loads of 8 mg g−1 cellulase and 2 mg g−1 amylase for both strains. When C. acetobutylicum cells were cultivated with pretreated P. kessleri bh-2 biomass, the biobutanol yield amounted to 4.8 gL-1 at a glucose concentration of 5.30 gL-1, demonstrating strain's superior performance compared to Scenedesmus sp.k-7. [Display omitted] • Microalgae are potential feedstocks for biofuel production. • Parachlorella kessleri bh-2 biomass holds promising potential for butanol production. • CO 2 as a carbon source enhanced P. kessleri bh-2 biomass and carbohydrate productivity. [ABSTRACT FROM AUTHOR]

This study investigates the impact of different biofuels, such as pure hydrogenated vegetable oil, hydrogenated vegetable oil, and biobutanol, as well as their blends, on the non-energetic operational characteristics of a compression ignition internal combustion engine. The research investigations were conducted using a turbocharged direct injection compression ignition engine that was put within a Skoda Octavia 1.9 TDI automobile. Throughout the investigation, the primary emphasis was placed on analyzing energy characteristics such as power, brake-specific fuel consumption (BSFC), brake thermal efficiency (BTE), and other related factors. The analysis involved the utilization of multiple combinations of bio-based fuels, namely four mixes of HVO with biobutanol (HVO100, HVOB5, HVOB10, and HVOB20), which were subsequently compared to fossil diesel (D100). The findings of the study indicate that the utilization of HVO100 fuel results in notable reductions in power output and mass fraction when compared to D100 gasoline. HVO100 fuel demonstrates superior performance to D100 gasoline, exhibiting a range of 1.7% to 28% improvement in brake-specific fuel consumption. Additionally, at an engine speed of 4500 rpm, the use of HVO100 fuel leads to a decrease in brake thermal efficiency of 4.4%. [ABSTRACT FROM AUTHOR]

Background: Distillers' grain waste (DGW) is the main by‐product in the Baijiu‐making process and its management remains a great challenge for the Baijiu industry. To address this issue, an integrated biobutanol and biomethane production process was established to obtain valuable products from DGW and reduce environmental pollution. Results: In the integrated process, DGW was hydrolyzed and detoxified to produce biobutanol, while the distillery waste derived from solvent extraction process was used for biomethane fermentation. After the optimization of overliming detoxification of DGW hydrolysate by artificial neural network and genetic algorithm, totals of 10.65 ± 0.07 g L−1 butanol and 4.51 ± 0.21 g L−1 isopropanol were attained with negligible amounts of acetone and ethanol (i.e. 0.14 ± 0.00 and 0.52 ± 0.06 g L−1, respectively). Anaerobic digestion of the distillery waste was efficient, and the chemical oxygen demand removal rate approached 92.3 ± 0.1% with a methane yield of 167.8 ± 1.2 mL g−1 TCODremoved. Moreover, the anaerobic digestion effluent could be recycled as a potential substitute for process water in biobutanol fermentation without having any negative effect on enzymatic hydrolysis of DGW, and the butanol production also reached 8.19 ± 0.29 g L−1. Conclusion: The present study provides a new idea for comprehensive utilization of DGW towards energy and resource recovery, without secondary pollution. © 2023 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

The escalating environmental concerns and burgeoning energy crises, coupled with the desire to achieve net-zero carbon emissions by 2050 to avert potential climate change disaster, highlight the urgent need for sustainable production methods, and innovative technological advancements. Microbial fermentation plays a pivotal role in the pursuit of sustainable production of biofuels and chemicals with properties similar to those of fossil-derived fuels and chemicals. Biofuels, such as biohydrogen and biobutanol derived from renewable sources, offer a promising, cost-effective, and eco-friendly solution for mitigating long-term carbon footprint. Currently, there is a surge of interest in biohydrogen (bioH2) and biobutanol production through dark fermentation using diverse biomass feedstocks, due to its capacity to simultaneously generate gas and liquid fuels from renewable nonfood resources. Furthermore, the incorporation of nanoparticles in fermentation process has demonstrated considerable potential in enhancing bioH2 yields. Similarly, biobutanol emerges as an eco-friendly, less polluting, and potentially commercially viable substitute for conventional gasoline. This review emphasizes the diverse spectrum of nanoparticle applications in biomanufacturing, with a particular focus on their role in enhancing microbial activities to boost bioH2 and biobutanol yields. Additionally, the review highlights potential underlying mechanisms of nano-catalyzed fermentation pathways, future trends, and the prospects of nano-catalysts in advancing biofuel technology.

Oil Palm Frond (OPF) juice has been the focus of Malaysian bioenergy producers through acetone-butanol-ethanol (ABE) fermentation. However, due to the high concentration of phenolic compounds in the hydrolysate, usually gallicacid and ferulic acids, the fermentation medium turns acidic which hinders the growth of most microorganisms. A suitable method of phenolic compound removal with a minimal effect on the sugar stability of OPF juice has been employed using Amberlite XAD-4 resin. During the detoxification process, the effects of temperature and pH on the removal of phenolic compounds and sugar stability were also assessed. The Amberlite XAD-4 resin managed to adsorb about 32% of phenolic compound from the OPF hydrolysate at an optimum temperature of 50 °C and hydrogen ion concentration (pH) of 6. In addition, it maintained as much as 93.7 % of the sugar in the OPF juice. The effect of detoxifying OPF hydrolysate was further tested for biobutanol production in batch culture using strain Clostridium acetobutylicum SR1, L2, and A1. Strain L2 gave the highest improvement in biobutanol and total solvent production by 22.7% and 14.41%, respectively, in medium with detoxified OPF juice. Meanwhile, compared to non-detoxified OPF juice, the acid production of strain L2 significantly decreased by 2.99-fold when using detoxified OPF juice, despite a 1.2-fold increase in sugar consumption. Conclusively, using Amberlite XAD-4 resin to detoxify OPF hydrolysate at pH 6 and 50 °C removed the phenolic compound while increasing the strain L2 capability to improve biobutanol and total solvent production.

Abstract In Germany alone, more than 5·106 tons of municipal green waste is produced each year. So far, this material is not used in an economically worthwhile way. In this work, grass clippings and tree pruning as examples of municipal green waste were utilized as feedstock for the microbial production of platform chemicals. A pretreatment procedure depending on the moisture and lignin content of the biomass was developed. The suitability of grass press juice and enzymatic hydrolysate of lignocellulosic biomass pretreated with an organosolv process as fermentation medium or medium supplement for the cultivation of Saccharomyces cerevisiae, Lactobacillus delbrueckii subsp. lactis, Ustilago maydis, and Clostridium acetobutylicum was demonstrated. Product concentrations of 9.4 gethanol L−1, 16.9 glactic acid L−1, 20.0 gitaconic acid L−1, and 15.5 gsolvents L−1 were achieved in the different processes. Yields were in the same range as or higher than those of reference processes grown in established standard media. By reducing the waste arising in cities and using municipal green waste as feedstock to produce platform chemicals, this work contributes to the UN sustainability goals and supports the transition toward a circular bioeconomy. Graphical Abstract

The increasing demand for sustainable energy has brought biobutanol as a potential substitute for fossil fuels. The Clostridium genus is deemed essential for biobutanol synthesis due to its capability to utilize various substrates. However, challenges in maintaining fermentation continuity and achieving commercialization persist due to existing barriers, including butanol toxicity to Clostridium, low substrate utilization rates, and high production costs. Proper substrate selection significantly impacts fermentation efficiency, final product quality, and economic feasibility in Clostridium biobutanol production. This review examines underutilized substrates for biobutanol production by Clostridium, which offer opportunities for environmental sustainability and a green economy. Extensive research on Clostridium, focusing on strain development and genetic engineering, is essential to enhance biobutanol production. Additionally, critical suggestions for optimizing substrate selection to enhance Clostridium biobutanol production efficiency are also provided in this review. In the future, cost reduction and advancements in biotechnology may make biobutanol a viable alternative to fossil fuels.

Butanol-producing strains Clostridium sp. UCM B-7570 and C. acetobutylicum UCM B-7407 were used for research from "Collection of strains of microorganisms and plant lines for food and agricultural biotechnology" of the Institute of Food Biotechnology and Genomics of the National Academy of Sciences of Ukraine, glycerol (BASF, Germany) and apple pomace (total moisture 4%) after apple juice production. The aim of this work was to study the possibility of using apple pomace by domestic butanol-producing strains of Clostridium sp. UCM B-7570 and C. acetobutylicum UCM B-7407 as a substrate. Producers were cultured on medium with different concentrations of apple pomace, glycerol was used for the inoculation. The presence of ethanol, acetone, and butanol in the culture liquid was determined using a gas chromatograph. It was determined that a significant part of the macrocomponent composition of the extracts can be used in bioconversion by producing strains of the genus Clostridium. It was determined that the highest concentration of butanol (10 g/dm3) was at a concentration of 120 g/dm3 in the extracts. The obtained data showed the possibility of using apple pomace as a substrate in biobutanol technology. Key points: • The highest butanol concentration (10 g/dm3) was accumulated using apple pomace. [ABSTRACT FROM AUTHOR]

Jackfruit (Artocarpus heterophyllus Lam) waste (JFW), a lignocellulosic biomass, is a potential raw material that can be tapped to produce energy and valuable products for human use. In the present work, biobutanol production was studied using jackfruit waste. Initially, the jackfruit waste was pretreated using acid and alkaline agents and hydrolyzed to produce fermentable sugars. The hydrolyzed jackfruit waste was fermented using Clostridium acetobutylicum NCIM 2877 to produce biobutanol. Among the studied pretreatments, sulfuric acid pretreatment produced a maximum sugar yield of 84.21 ± 2.6 mggds−1 in the acid liquor. Enzyme hydrolysis of pretreated jackfruit waste produced a total glucose yield of 215.12 ± 13.44 mggds−1 after optimization. After detoxification using activated charcoal, the JFW hydrolysate produced a maximum biobutanol titer and yield of 1.60 ± 0.5 g L−1, and 106.59 ± 5.1 mg/gglucose, respectively. Central composite design optimization of acetone‐butanol‐ethanol fermentation produced a maximum biobutanol titer of 5.6 ± 0.2 g L−1 (250.00 ± 11.4 mg/gglucose) and total solvent titer of 7.28 ± 0.3 g L−1 (325.00 ± 13.1 mg/gglucose). A 31 ton annual biobutanol production from JFW, simulated using SuperPro Designer, revealed the unit production cost and payback time to be $10.49/kg and 8.94 years. [ABSTRACT FROM AUTHOR]

The main problems with the butanol fermentation process include high cost of grain raw materials, low product concentration and low butanol productivity caused by butanol cytotoxicity. In this study, cassava, a cheap crop, was used as the raw material. A symbiotic system TSH06, which possesses the capability to synthesize butanol under non-strict anaerobic conditions, was used as the fermentation strain. The fermentation performance of TSH06 in a cassava system was investigated. In order to eliminate product inhibition and promote the concentration and productivity of butanol, a strategy of continuous fermentation coupled with online gas stripping was developed. By using the strategy of two-stage continuous fermentation using immobilized cells coupled with online gas stripping, the butanol productivity reached 0.9 g/(L·h); at the same time, a high butanol concentration was achieved, and the concentration of butanol obtained in the condensate reached 71.2 g/L. [ABSTRACT FROM AUTHOR]

Biobutanol is a potential biofuel produced from various biomass and can serve as a suitable alternative to the nonrenewable fossil-based gasoline fuel. The fermentative microbes used for biobutanol production are solvent-producing Clostridium organisms by Acetone-Butanol-Ethanol (ABE) fermentation. The major challenges of ABE fermentation are butanol toxicity to the host strain, lack of effective fermentation strategies, inefficient butanol separation, and low 0.5–2% w/w yield. Butanol forms an azeotropic mixture with water and requires 79.5 MJ/kg energy for separation using conventional distillation when the energy content of butanol is only 36 MJ/kg; hence the separation by traditional distillation processes is inefficient. Recent developments in membrane technology, coupled with novel extractants and adsorbents, are promising for efficient, energy-effective, and economical bio-butanol separation. Among the techniques, liquid-liquid extraction has shown a high separation efficiency of 75–85% butanol with an energy demand of 25 MJ/kg, whereas adsorption and pervaporation have shown an energy demand of 35–40 MJ/kg. In the present review, a critical analysis of the recent trends, strategies, technical prospects, challenges, and economical evaluation of different methods of biobutanol recovery is presented. [ABSTRACT FROM AUTHOR]

Oil Palm Frond (OPF) juice has been the focus of Malaysian bioenergy producers through acetone-butanolethanol (ABE) fermentation. However, due to the high concentration of phenolic compounds in the hydrolysate, usually gallicacid and ferulic acids, the fermentation medium turns acidic which hinders the growth of most microorganisms. A suitable method of phenolic compound removal with a minimal effect on the sugar stability of OPF juice has been employed using Amberlite XAD-4 resin. During the detoxification process, the effects of temperature and pH on the removal of phenolic compounds and sugar stability were also assessed. The Amberlite XAD-4 resin managed to adsorb about 32% of phenolic compound from the OPF hydrolysate at an optimum temperature of 50 ℃ and hydrogen ion concentration (pH) of 6. In addition, it maintained as much as 93.7 % of the sugar in the OPF juice. The effect of detoxifying OPF hydrolysate was further tested for biobutanol production in batch culture using strain Clostridium acetobutylicum SR1, L2, and A1. Strain L2 gave the highest improvement in biobutanol and total solvent production by 22.7% and 14.41%, respectively, in medium with detoxified OPF juice. Meanwhile, compared to non-detoxified OPF juice, the acid production of strain L2 significantly decreased by 2.99-fold when using detoxified OPF juice, despite a 1.2-fold increase in sugar consumption. Conclusively, using Amberlite XAD-4 resin to detoxify OPF hydrolysate at pH 6 and 50 ℃ removed the phenolic compound while increasing the strain L2 capability to improve biobutanol and total solvent production. [ABSTRACT FROM AUTHOR]

Palm oil methyl ester (POME) has been partially blended with diesel and applied to diesel vehicles according to its advantages of lowering carbon monoxide (CO) and particulate matter (PM) but carbon dioxide (CO2) and nitrogen oxides (NOx) are yet trade-off. By premixed combustion technique, performance and exhaust emissions of a diesel engine-generator system fueled with POME combined with carbureting biobutanol are studied, at 3,000 rpm speed under load variation without engine re-calibration. POME was combined with the low activity biobutanol, supplied by carburetion with the rates of 0.20 to 0.34 g/s. The results of the engine test have shown the continuous reduction of engine performance and exhaust emissions for the highly fumigated biobutanol, combined with POME. The POME combined with 0.20 g/s carbureting biobutanol improved the thermal efficiency, albeit the specific fuel consumption was slightly higher than the neat POME. The releases of CO2, NOxand PM were reduced by 5%, 6% and 24%, respectively but suffering from 18% CO incrementation compared with POME. The premixed biobutanol is limited by a carburetor main jet that may lead to the addition of CO. The premixing method modification is required for further research.

Biobutanol is a valuable biochemical and one of the most promising biofuels. Clostridium saccharoperbutylacetonicum N1-4 is a hyperbutanol-producing strain. However, its strong autolytic behavior leads to poor cell stability, especially during continuous fermentation, thus limiting the applicability of the strain for long-term and industrial-scale processes. In this study, we aimed to evaluate the role of autolysin genes within the C. saccharoperbutylacetonicum genome related to cell autolysis and further develop more stable strains for enhanced butanol production. First, putative autolysin-encoding genes were identified in the strain based on comparison of amino acid sequence with homologous genes in other strains. Then, by overexpressing all these putative autolysin genes individually and characterizing the corresponding recombinant strains, four key genes were pinpointed to be responsible for significant cell autolysis activities. Further, these key genes were deleted using CRISPR-Cas9. Fermentation characterization demonstrated enhanced performance of the resultant mutants. Results from this study reveal valuable insights concerning the role of autolysins for cell stability and solvent production, and they provide an essential reference for developing robust strains for enhanced biofuel and biochemical production.IMPORTANCE Severe autolytic behavior is a common issue in Clostridium and many other microorganisms. This study revealed the key genes responsible for the cell autolysis within Clostridium saccharoperbutylacetonicum, a prominent platform for biosolvent production from lignocellulosic materials. The knowledge generated in this study provides insights concerning cell autolysis in relevant microbial systems and gives essential references for enhancing strain stability through rational genome engineering.

To carry out the calculations required for modelling and computing for kinetics biobutanol and bioethanol yields and production rates, several procedures should be accomplished; this requires time and effort, and there is a chance that mistakes will be made. The goal of this study is to provide a tool that will assist users, engineers, and experts in conducting these computations by creating a mobile application to reduce time and effort. The calculations were carried out using a mathematical model. The mathematical model was then included in a flowchart that was created later. After that, Kodular was used to configure the mobile application by fusing the interface design, mathematical model, and flowchart. Information was gathered from publications, wastewater treatment facilities, non-governmental organizations (NGOs), and government groups. To offer output data that matched the output data obtained from the configured program, the data collected for doing the calculations in the conventional manner was used. Both the standard strategy and the program's outcomes were consistent. The created mobile application can do kinetic modeling and determine the yields and rates of generation of biobutanol and bioethanol from agricultural waste. [ABSTRACT FROM AUTHOR]