Abstract
Biomass and other carbonaceous materials can be gasified to produce syngas with high concentrations of CO and H2. Feedstock materials include wood, dedicated energy crops, grain wastes, manufacturing or municipal wastes, natural gas, petroleum and chemical wastes, lignin, coal and tires. Syngas fermentation converts CO and H2 to alcohols and organic acids and uses concepts applicable in fermentation of gas phase substrates. The growth of chemoautotrophic microbes produces a wide range of chemicals from the enzyme platform of native organisms. In this review paper, the Wood–Ljungdahl biochemical pathway used by chemoautotrophs is described including balanced reactions, reaction sites physically located within the cell and cell mechanisms for energy conservation that govern production. Important concepts discussed include gas solubility, mass transfer, thermodynamics of enzyme-catalyzed reactions, electrochemistry and cellular electron carriers and fermentation kinetics. Potential applications of these concepts include acid and alcohol production, hydrogen generation and conversion of methane to liquids or hydrogen.
Highlights
Introduction to Syngas FermentationSyngas fermentation is a hybrid thermochemical/biochemical platform that takes advantage of the simplicity of the gasification process and the specificity of the fermentation process to deliver ethanol and potentially other chemicals
We present a review of feedstocks, syngas production, metabolic pathway, bioreactor design, mass transfer, thermodynamics, electrochemistry and microbial kinetics of the syngas fermentation process and propose a conceptual model to describe the syngas fermentation
When gasification is coupled with fermentation of the syngas, the robustness and adaptability of the acetogenic bacteria reduce the requirements for gas cleaning and adjustment by the water gas shift reaction required for catalytic conversion of syngas
Summary
Syngas fermentation is a hybrid thermochemical/biochemical platform that takes advantage of the simplicity of the gasification process and the specificity of the fermentation process to deliver ethanol and potentially other chemicals. Energy-rich biomass and waste materials are converted by gasification to syngas, which consists of CO, H2 and CO2 These gases are converted to ethanol and other chemicals by acetogenic autotrophic microbes [2]. Efficiency represented retaining the heating the value from the products, through gasification [5] product and as increased product yield from fermentation products, through gasification [5] and as increased yield from fermentation [6], and the use of [6], andefficient the useseparation of energy technologies, efficient separation such as membrane separation, very energy such astechnologies, membrane separation, are very important toare achieve achieve a profitable commercial process for fuels or chemicals.
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
