Title: Tandem Lewis/Brønsted homogeneous acid catalysis: conversion of glucose to 5-hydoxymethylfurfural in an aqueous chromium(iii) chloride and hydrochloric acid solution

Abstract

Here, a kinetic model for the tandem conversion of glucose to 5-hydroxymethylfurfural (HMF) through fructose in aqueous CrCl₃–HCl solution was developed by analyzing experimental data. We show that the coupling of Lewis and Brønsted acids in a single pot overcomes equilibrium limitations of the glucose–fructose isomerization leading to high glucose conversions and identify conditions that maximize HMF yield. Adjusting the HCl/CrCl₃ concentration has a more pronounced effect on HMF yield at constant glucose conversion than that of temperature or CrCl₃ concentration. This is attributed to the interactions between HCl and CrCl₃ speciation in solution that leads to HMF yield being maximized at moderate HCl concentrations for each CrCl₃ concentration. This volcano-like behavior is accompanied with a change in the rate-limiting step from fructose dehydration to glucose isomerization as the concentration of the Brønsted acid increases. The maximum HMF yield in a single aqueous phase is only modest and appears independent of catalysts’ concentrations as long as they are appropriately balanced. However, it can be further maximized in a biphasic system. Our findings are consistent with recent studies in other tandem reactions catalyzed by different catalysts.

Authors:

Swift, T. Dallas ^[1]; Nguyen, Hannah ^[1]; Anderko, Andrzej ^[2]; Nikolakis, Vladimiros ^[1]; Vlachos, Dionisios G. ^[1]

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+ Show Author Affiliations

1. Univ. of Delaware, Newark, DE (United States)
2. OLI Systems Inc., Cedar Knolls, NJ (United States)

Publication Date:

2015-07-25

Research Org.:

Energy Frontier Research Centers (EFRC), Washington, D.C. (United States). Catalysis Center for Energy Innovation (CCEI)

Sponsoring Org.:

USDOE Office of Science (SC), Basic Energy Sciences (BES)

OSTI Identifier:

1370906

Grant/Contract Number:  

SC0001004

Resource Type:

Accepted Manuscript

Journal Name:

Green Chemistry

Additional Journal Information:

Journal Volume: 17; Journal Issue: 10; Related Information: CCEI partners with the University of Delaware (lead); Brookhaven National Laboratory; California Institute of Technology; Columbia University; University of Delaware; Lehigh University; University of Massachusetts, Amherst; Massachusetts Institute of Technology; University of Minnesota; Pacific Northwest National Laboratory; University of Pennsylvania; Princeton University; Rutgers University; Journal ID: ISSN 1463-9262

Publisher:

Royal Society of Chemistry

Country of Publication:

United States

Language:

English

Subject:

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY; catalysis (homogeneous); catalysis (heterogeneous); biofuels (including algae and biomass); bio-inspired; hydrogen and fuel cells; materials and chemistry by design; synthesis (novel materials); synthesis (self-assembly); synthesis (scalable processing)