Investigation of the Effect of Zeolite Supports and the Role of W‐Species for One‐Pot Catalytic Conversion of Cellulose to Ethylene Glycol: Theoretical & Experimental Studies.

Abstract

AbstractEndeavors were made to study the influence of various zeolite (HY, NaY, NaZSM‐5 and HZSM‐5) supports with (Al)−Ni−W metal combination catalysts for the ethylene glycol (EG) production, selectively from cellulose. From the experimental results ZSM‐5 (NaZSM‐5/73.3% & HZSM‐5/67.7%) support is superior over HY & NaY support in selective EG production from cellulose. It was understood that W‐ species with oxygen vacancies (WO3‐x, XPS analysis) plays an important role in producing the glycolaldehyde (GA) intermediate (via C−C cleavages), which on hydrogenation over Ni‐ sites selectively produce EG. Further, the studies based on the Density Functional Theory (DFT) were conducted to substantiate the involvement of the WO3‐x species in the reaction. The adsorption energies and structural changes establish that the C2−C3 bond of the glucose elongates and thereby activates on adsorbing to WO3‐x sites supporting the formation of GA. Activation of GA on Ni‐ sites is distinguished by an increase of 0.1 Å in C=O bond length, which facilitates the hydrogenation of C=O resulting in EG. The reaction pathway is explained through an analysis of CDD and DOS.