In the practical process for

in 2005 for the production of biodiesel [185]. Following their work, a great many of carbonaceous solid acid catalysts, which are generally prepared by the incomplete carbonization of natural organic matters and the subsequent sulfonation of the resulting amorphous carbons in the presence of concentrated sulfuric acid, fuming sulphuric acid or chlorosulfonic acid [186], [187], [188], [189], [190], [191], [192], [193], [194] and [195], have been designed for the hydrolysis of cellulose.