Comparison of hydrogen fluoride saccharification of lignocellulosic materials with other saccharification technologies

Abstract

Laboratory investigations have been conducted for the past year in the MSU-DOE Plant Research Laboratory in collaboration with Chemical Engineering at Michigan State University on the hydrogen fluoride (HF) saccharification of cellulose and wood. Our work is an extension of the work done by Fredenhagen in Germany reported in 1933. We have produced evidence that HF saccharification of lignocellulosic materials when compared with hydrolysis saccharification techniques has the important features of: (1) high conversion of cellulose and hemicellulose to simple sugars; (2) recycle of HF in the process thereby eliminating the need for major acid neutralization requirements; (3) a valuable lignin byproduct for chemical use; and (4) no elaborate pretreatment requirements. High sugar yields and chemically useful lignin are essential in the long term if biomass is to replace petroleum and later coal as sources of chemical raw materials and liquid fuels. There are several laboratory investigations recommended in order to more fully evaluate the potential of HF saccharification of lignocellulosic materials. These investigations include studies on reaction conditions versus yield, removal and recycle methods, post-hydrolysis conditions versus oligomer distribution, sugar separation methods, and basic studies on uses for xylose and lignin. Results of these studies could be utilized to develop a process design and economic evaluation of the HF technology and to identify those processing steps which require pilot scale experimentation.