Composite coal fly ash solid acid catalyst in synergy with chloride for biphasic preparation of furfural from corn stover hydrolysate

摘要

A solid acid catalyst SO42-/SnO2-Al2O3-CFA was synthesized based on industrial waste coal fly ash (CFA) as carrier and applied in the conversion of oxalic acid pretreated corn stover hydrolysate to produce furfural. Physical properties of the solid acid catalyst were characterized by SEM, FTIR, XRD, BET, EDAX, and NH3-TPD. Highly wrinkled structure of SO42-/SnO2-Al2O3-CFA could provide more specific surface area for the covalent linkage between SiO2 and SnO2. Factors influencing the efficacy of SO42-/SnO2-Al2O3-CFA were systematically explored. The highest furfural yield of 84.7% was reached in NH4Cl-toluene biphasic system at 180 degrees C for 30 min. The recyclability of SO42-/SnO2-Al2O3-CFA and toluene could be achieved for five batches with stable performance in transformation of xylose-rich corn stover hydrolysate. This study provided a novel solid acid catalyst with promising potential in the synthesis of furfural from corn stover.