Efficient Conversion of Maltose into Sorbitol over Magnetic Catalyst in Extremely Low Acid

Abstract

Ni/Cu/Al/Fe hydrotalcite precursor was synthesized by a co-precipitation method. The activity of the reduced precursor for one-step conversion of maltose into sorbitol in the presence of H2 and extremely low phosphoric acid was investigated. XRD and XPS tests provided the essential properties of the precursor and prepared magnetic catalyst. Effects of various processing parameters towards the reaction performance were studied in detail. A desired sorbitol yield of 93.1% was attained at 458 K for 3 h with a catalyst dosage of 20%. A catalyst recycling experiment demonstrated that Ni4.63Cu1Al1.82Fe0.79 was a better catalyst and could be reused three or four times. The specific reasons for catalyst deactivation were considered in depth.