Catalytic hydrolysis of cellulose to total reducing sugars with superior recyclable magnetic multifunctional MCMB‐based solid acid as a catalyst

Abstract

AbstractBACKGROUNDEffective cellulose hydrolysis has a huge potential for producing high value‐added biomass‐based platform chemicals, such as glucose, hydroxymethylfurfural, levulinic acid, and total reducing sugars (TRS). Particularly, a magnetic multifunctional solid acid catalyst (Fe3O4/Cl–MCMB–SO3H) was synthesized by loading the active groups on the magnetic mesocarbon microbead (MCMB) derived from the co‐calcination of coal tar pitch and ferroferric oxide, which was applied as a catalyst in the conversion of cellulose into TRS.RESULTSGiven the superior properties of MCMB, a novel magnetic MCMB‐based solid acid with cellulose‐binding domain (–Cl group) and catalytic domain (–SO3H group) was successfully prepared. Results indicated that this catalyst exhibited superior catalytic activity, recyclability and regenerability, and easy separation from the reactant. The acidic densities of –SO3H and –Cl in Fe3O4/Cl–MCMB–SO3H reached 1.77 and 1.32 mmol/g, respectively. The 68.6% TRS yield can be obtained from cellulose at 140 °C for 3 h in distilled water by using Fe3O4/Cl‐MCMB‐SO3H as the catalyst. The TRS yield still reached 61.1% after the catalyst was used six times. Importantly, through catalyst regeneration, the –SO3H density and TRS yield still reached 1.69 mmol/g and 67.3%, indicating that the catalyst exhibited excellent regenerability.CONCLUSIONSuch multifunctional magnetic catalyst would be a promising catalyst in the conversion of cellulose into biofuels, which was attributed to the efficient catalytic performance, magnetism, and excellent recyclability and regenerability. © 2019 Society of Chemical Industry