Pentose syrup production from hemicellulose

摘要

A method for the production of pentose syrup from hemicellulosic material comprising the separate steps of: (a) mixing said hemicellulose material with an acid selected from the group consisting of sulfuric and hydrochloric to obtain a final concentration of from about 1% to 15% at liquid:solid ratios between 0.1 and 4.0 whereby the material is ready for hydrolyzing directly or being stored for an indefinite period of time at ambient temperatures without degradation; (b) hydrolyzing the acidified material from step (a) by heating the material to a reaction temperature of from 90 DEG to 120 DEG C. for a period of time sufficient to hydrolyze substantially all of the hemicellulose; (c) leaching the hydrolyzed material at a temperature of from about 15 DEG to 100 DEG C. with an aqueous medium by percolating said medium through the hydrolyzed material at a velocity of 0.016 to 0.83 mm/sec; and (d) recovering a syrup containing at least 5 percent of pentoses whereby there is obtained a pentose syrup having a low PH and suitable for storage for extended periods of time without microbial degradation. The hydrolysis and leaching steps are carried out in a packed bed reactor. The resulting pentose syrup may be subsequently fermented to produce alcohol.