A New Facilitated Process of Biomass-Derived Furans to p-Xylene with Ethanol over Zeolite

In a typical experiment, 15 mL of the model compound 2,5-Dimethylfuran (99% Sigma-Aldrich), 8.2 mL of ethanol (99.5% Sigma-Aldrich) and 0.4 g of zeolite were used over a temperature range of 200 to 300 °C and 1.0 mL of tridecane as an internal standard. The reaction vessel was flushed with inert gas (N2). Liquid products were identified and quantified using a gas chromatograph/mass spectrometer (Agilent 6890 and Agilent MSD 5973 (N)) calibrated with pure standards. After reaction, the autoclave was cooled down to −60°C by dry ice/acetone bath. The gas products (CO, CO2, CH4) analyzed by a Perkin Elmer Autosystem XL Arnel Gas phase GC-FID-Methanator. C2H4 gas product was assumed to be mainly produced from ethanol. The solid residue was filtrated and washed with acetone and dried overnight (80 °C). Then it was analyzed by thermogravimetric analyses (TA instruments Q50), the samples were heated at 10 °C min from room temperature to 900 °C under air to quantify the coke on zeolite to complete the carbon balance. The conversion was expressed in term of the molar conversion of 2,5-dimethylfuran and carbon balance was achieved at the minimum of 90-95%.