Two-stage dilute-acid pretreatment of softwoods |
| |
Authors: | Nguyen Quang A Tucker Melvin P Keller Fred A Eddy Fannie P |
| |
Institution: | (1) National Renewable Energy Laboratory, 1617 Cole Boulevard, 80401-3393 Golden, CO |
| |
Abstract: | Whole treechips obtained from softwood forest thinnings were pretreated via single-and two-stage dilute-sulfuric acid pretreatment.
Whole-tree chips were impregnated with dilute sulfuric acid and steam treated in a 4-L steam explosion reactor. In single-stage
pretreatment, wood chips were treated using a wide range of severity. In two-stage pretreatment, the first stage was carried
out at low severity tomaximize hemicellulose recovery. Solubilized sugars were recovered from the first-stage prehydrolysate
by washing with water. In the second stage, water-insoluble solids from first-stage prehydrolysate were impregnated with dilute
sulfuric acid, then steam treated at more severe conditions to hydrolyze a portion of the remaining cellulose to glucose and
to improve the enzyme digestibility. The total sugar yields obtained after enzymatic hydrolysis of two-stage dilute acid-pretreated
samples were compared with sugar yields from single-stage pretreatment. The overall sugar yield from two-stage dilute-acid
pretreatment was approx 10% higher, and the net enzyme requirement was reduced by about 50%. Simultaneous saccharification
and fermentation using an adapted Saccharomyces cerevisiae yeast strain further improved cellulose conversion yield and lowered the enzyme requirement. |
| |
Keywords: | Softwood pretreatment acid hydrolysis enzymatic hydrolysis ethanol |
本文献已被 SpringerLink 等数据库收录! |
|