275222 Cycloaddition of Biomass Derived Furans for the Renewable Production of p-Xylene

Tuesday, October 30, 2012: 1:10 PM
315 (Convention Center )
Christopher L. Williams1, Chun-Chih Chang1, Phuong T. Do2, Nima Nikbin2, Stavros Caratzoulas3, Dionisios G. Vlachos4, Raul F. Lobo2, Wei Fan1 and Paul Dauenhauer1, (1)Chemical Engineering, University of Massachusetts Amherst, Amherst, MA, (2)Chemical Engineering, University of Delaware, Newark, DE, (3)Catalysis Center for Energy Innovation, University of Delaware, Newark, DE, (4)Catalysis Center for Energy Innovation, Chemical and Biomolecular Engineering, University of Delaware, Newark, DE

Increasing demand for domestic energy and renewable materials has led to an accelerated research effort to develop biomass-derived fuels and chemicals [1]. One sustainable feedstock for these renewable chemicals is sugars produced by the saccharification of biopolymers (e.g., cellulose, hemicellulose) [2]. The catalytic conversion of sugars to high value commodity chemicals, like p-xylene (used in the production of PET plastics [3]), is currently a research area of interest [4]. In this work, we investigate the conversion of dimethylfuran to p-xylene by a two-part reaction (Diels-Alder cycloaddition followed by dehydration).  By reacting dimethylfuran with high-pressure ethylene, competitive side reactions that reduce p-xylene yield are identified and minimized. Multiple catalyst types are investigated providing insight into the relevant catalyst active sites and microstructure. 75% yield of p-xylene is demonstrated using Y-zeolite in combination with an aliphatic solvent at high temperature.  Additionally, it is found that Diels-Alder cycloaddition (the first step in conversion of DMF to p-xylene) is promoted by confinement within microstructured zeolites and the second step (dehydration) is catalyzed by Brønsted acid sites, rendering the first step (cycloaddition) rate limiting. Gas phase DFT calculations supporting the necessity of Brønsted acid sites are also presented. This catalytic system introduces a new chemical pathway to convert biomass-derived furans to high-value aromatic feedstocks.



[1] Climent, M. J.; Corma, A.; Iborra, S. Green Chemistry 2011, 13, 520-540

[2] Vlachos, D. G.; Chen, J. G.; Gorte, R. J.; Huber, G. W.; Tsapatsis, M. Catalysis Letters 2010, 140, 77-84.

[3] Sheehan, R. J. In Ulmann's Encyclopedia of Industrial Chemistry; Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim, 2011; pp. 17-28

[4] Williams, C. L.; Chang, C.-chih; Do, P.; Nikbin, N.; Caratzoulas, S.; Vlachos, D. G.; Lobo, R. F.; Fan, W.; Dauenhauer, P. J. ACS Catalysis 2012, 2, 935-939



Extended Abstract: File Not Uploaded