Recent innovations for reviving the ABE fermentation for production of butanol as a drop-in liquid biofuel

Abstract

Butanol is a key microbial product that provides a route from renewable carbohydrate resources to a "drop-in" liquid biofuel, broadening its market in the near future. The acceptable performance of butanol as a neat or a blended fuel in different engines both from the technical and environmental points of view has attracted a wide range of research for reviving the old acetone-butanol-ethanol (ABE) fermentation. In this review, recent findings on fuel characteristics of butanol, different generations of substrate for large scale butanol production, and alternative process designs for upstream, mainstream, and downstream operations have been critically reviewed and discussed. In the upstream, studies devoted to designing and optimization of pretreatments based on prerequisites of butanol production, e.g., maximizing cellulose and hemicellulose recovery and minimizing lignin degradation, are presented. In the mainstream, different microbial systems and process integrations developed for facilitating ABE production (e.g., in-situ butanol removal) are scrutinized. Finally, innovations in ABE recovery and purification as "Achilles Heel" of butanol production processes which directly controls the energy return on investment (EROI), are reviewed and discussed.

Developments in Downstream Butanol Separation from Acetone, Butanol, and Ethanol Fermentation

“…In this context, biofuels are a remarkable option. Among them, butanol produced by fermentation has stood out for his potential as biofuel and for being useful in many industrial applications [1][2][3][4][5][6].…”

Hexanol biosynthesis from syngas by Clostridium carboxidivorans P7 – product toxicity, temperature dependence and in situ extraction

“…The traditional route for biotechnological butanol production from renewable resources is acetone-butanol-ethanol (ABE) fermentation. This process has been known for more than a century ( Jones and Woods, 1986 ; Weizmann, 1915 ) and research is still ongoing ( Amiri, 2020 ; Friedl, 2016 ; Li et al., 2021 ; Pudjiastuti et al., 2021 ). In this sugar based fermentation process, biomass from different sources can be used as feedstock.…”

“…The use of municipal solid waste or lignocellulosic biomass derived from agricultural byproducts allows for the potential reduction of CO 2 emissions, but requires pretreatment of the substrates as well as downstream processing of the fermentation broth for the isolation of the different end products. The energy needed for these steps significantly influences the return on investment of this process ( Amiri, 2020 ; Friedl, 2016 ).…”

“…Since the available products of syngas fermentations are broadly similar to the products of ABE fermentations (mostly short to medium chain organic acids and alcohols), downstream processing technologies like product separation techniques initially developed for ABE fermentation can be adapted for syngas fermentation. Many technologies like adsorption, gas stripping, liquid-liquid extraction, membrane extraction, membrane distillation, reverse osmosis, thermopervaporation, sweeping gas pervaporation, and vacuum pervaporation were applied in ABE fermentations and are reviewed elsewhere ( Amiri, 2020 ; Friedl, 2016 ; Núñez-Gómez et al., 2014 ; Vees et al., 2020 ).…”

Advanced Metabolic Engineering Approaches and Renewable Energy to Improve Environmental Benefits of Algal Biofuels: LCA of Large-scale Biobutanol Production with Cyanobacteria Synechocystis PCC6803

“…Considering conventional acetone-butanol-ethanol (ABE) fermentation, several critical aspects, e.g. recovery and purification methods, influencing the energy return on investment (EROI) similar to in the presented biobutanol production [23][24][25][26][27]. Nevertheless, Garcia et al [28] highlight the potential of improving the overall efficiency of the fermentation by adequate pretreatment of the raw material, altering the fermentation process itself, product recovery and purification processes.…”