Applied Energy, Vol.160, 990-998, 2015
Hydrogenation and hydrodeoxygenation of difurfurylidene acetone to liquid alkanes over Raney Ni and the supported Pt catalysts
Direct HDO process for difurfurylidene acetone dimer (F2A) conversion to liquid alkanes (C8 C14) at 260 degrees C in a batch reactor was investigated over different material supported 1 wt%Pt catalysts, including SAPO-11, HZSM-5, SiO2-Al2O3, MCM-22, and home-made SiO2-ZrO2. CS-Cm alkanes of 55.8% was obtained over the optimized I wt%Pt/SiO2-ZrO2 due to its proper pore size of 9.0 nm and moderate acidic centers, together with more than 10% carbon yield of the oxygenated hydrocarbons, including C11-C13 chain alcohols 82 ketones and the hydrogenated F(2)A dimers with furan ring (H-F(2)A dimers). To improve the liquid alkane yield, a two-step process for F(2)A conversion was also investigated, which included low-temperature hydrogenation at 50 C over Raney Ni catalyst in a batch reactor and the subsequent high-temperature hydrodeoxygenation (HDO) at 280 degrees C over 1 wt%Pt/SiO2 ZrO2 in a fixed-bed reactor. The selectivity of 1,5-di(tetrahydro-2-furany1)-3-pentanol (II-c) was the highest of 83.0% among the hydrogenated intermediates of H-F2A dimers due to the protonation effect of methanol as the solvent and the hydrogenation of C=C bonds by Ni active centers. In the same time, the high content of this saturated alcohol H-dimer of II-C increased the solubility and stability of the intermediates in methanol solvent. High carbon yield of C-8-C-14 alkanes of 82.9%(mol) was obtained after oxygen atom removal from H-F(2)A dimers via, the second-step HDO reaction. Long time operation showed the stability of 1 wt%Pt/SiO2-ZrO2 as HDO catalyst, deduced from the steady phase structure, acidity of SiO2 ZrO2 support and Pt active centers by catalyst characterization. (C) 2015 Elsevier Ltd. All rights reserved.
Keywords:Hydrogenation/hydrodeoxygenation;Difurfurylidene acetone;Liquid alkanes;Raney Ni;Pt catalysts;Catalytic conversion