Biomass Refineries Based on Hybrid Thermochemical‐Biological Processing‐An Overview

Biomass pyrolysis for chemicals

“…In 1999 So and Brown [49,50] compared the cost of producing ethanol from cellulosic biomass via a hybrid thermochemical biorefinery approach, analogous to Shafizadeh's concept [7], to acid hydrolysis and enzymatic hydrolysis technologies. The results indicate that the production cost of ethanol via the fast pyrolysis based concept is competitive with the production cost via the conventional approaches.…”

Biomass Pyrolysis for Hybrid Biorefineries

“…4 The acid hydrolysis transforms the hemicellulose in water-soluble carbohydrates while the subsequent fast pyrolysis step converts the resulting lignocellulose complex into a high levoglucosan-containing biooil. [52][53][54] In 1999, they compared the cost of producing ethanol from cellulosic biomass via the hybrid thermochemical biorefinery approach, to acid hydrolysis and enzymatic hydrolysis technologies. The highest yield of this process was found especially for softwoods, since their hemicelluloses contain a large fraction of (fermentable) C 6 sugars (mannose and galactose).…”

An examination of biorefining processes, catalysts and challenges

“…Autotrophs use C1 compounds, such as CO, CO 2 and methanol, for their carbon source and hydrogen as their energy source while unicarbonotrophs use C1 compounds alone for both these purposes [142]. These microorganisms also utilise metals such as cobalt and nickel (which are contained in their enzymes) for the conversion of C1 compounds into value added products such as ethanol, but they are less sensitive to many of the gas contaminants, such a sulphur, that poison metal-based catalysts [143].…”

“…These microorganisms also utilise metals such as cobalt and nickel (which are contained in their enzymes) for the conversion of C1 compounds into value added products such as ethanol, but they are less sensitive to many of the gas contaminants, such a sulphur, that poison metal-based catalysts [143]. Also, the adjustment of the H 2 :CO ratio via the water gas shift reaction is not necessary where biological catalysts are employed and synthesis conditions can be much milder [142]. Alico Inc. aim to use Clostridium ljungdahlii to produce ethanol from syngas in their planned commercial biorefinery.…”