The invention relates to a comprehensive utilization process of the classification conversion of
straw. The process is characterized in that the
straw is split selectively and structurally by the combined pretreatment technology in which
steam explosion is taken as a core to form
hemicellulose-enriched washing liquor, a
hybrid-
cell-enriched component, a
cellulose-enriched component and a
lignin component; and
steam explosion washing liquor is catalyzed directly to form
furfural, the
hybrid-
cell-enriched component is burned to form nanometer
silicon dioxide, the
cellulose-enriched component and the
lignin component are liquefied respectively to form
plant-based polyether polyalcohol, and the
lignin component is also used for preparing phenolic resin further. In the method, the
furfural is prepared by a two-
step method, so the conversion rate is improved; a
solid acid catalyst also can be used repeatedly, and the
cellulose-enriched component and the lignin component are liquefied respectively, so the conversion rate of a substrate is improved; and the relative molecular weight of the polyether polyalcohol is distributed narrowly, so the polyether polyalcohol can be used for preparing high-quality
polyurethane materials. By the method, the problems of low conversion efficiency, secondary
pollution and the like during the utilization of the integral
plant of the
straw are solved, and the high-efficiency cleaning conversion of the straw is realized.