ABSTRACT A solid acid catalyst of zirconium sulfate (ZS) on a pure hexagonal mesoporous silica (HMS) sieve was prepared and characterized by small angle X-ray diffraction, NH3-temperature programmed desorption, and thermogravimetric analysis. The obtained ZS/HMS catalyst displayed a typical mesoporous structure, ZS was well dispersed on the HMS support, and the acidity increased with the amount of ZS loading. Gossypol was extracted from cottonseed cake with acetone as solvent, and then the gossypol solution was esterified with ZS/HMS as catalyst to yield products of acetic acid gossypol. Under the optimal conditions, the conversion efficiency of gossypol was as high as 96.7%.
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