文献类型：期刊文献

英文题名：Poison Tolerance to the Selective Hydrogenation of Cinnamaldehyde in Water over an Ordered Mesoporous Carbonaceous Composite Supported Pd Catalyst

作者：Chen, Shangjun[1,2];Meng, Li[1,2];Chen, Bingxu[3];Chen, Wenyao[3];Duan, Xuezhi[3];Huang, Xing[4];Zhang, Bingsen[5];Fu, Haibin[1,2];Wan, Ying[1,2]

机构：[1]Shanghai Normal Univ, Shanghai Key Lab Rare Earth Funct Mat, Minist Educ, Key Lab Resource Chem, Shanghai 200234, Peoples R China;[2]Shanghai Normal Univ, Dept Chem, Shanghai 200234, Peoples R China;[3]East China Univ Sci & Technol, State Key Lab Chem Engn, 130 Meilong Rd, Shanghai 200237, Peoples R China;[4]Fritz Haber Inst Max Planck Soc, Dept Inorgan Chem, Faradayweg 4-6, D-14195 Berlin, Germany;[5]Chinese Acad Sci, Inst Met Res, Shenyang Natl Lab Mat Sci, Shenyang 110016, Peoples R China

年份：2017

卷号：7

期号：3

起止页码：2074

外文期刊名：ACS CATALYSIS

收录：;EI(收录号：20173204025175);WOS:【SCI-EXPANDED(收录号:WOS:000395726500070)】；

基金：This work was supported by the State Key Basic Research Program of China (2013CB934102), NSF of China (21322308), Ministry of Education of China (PCSIR-T_IRT_16R49 and 20123127110004), International Joint Laboratory on Resource Chemistry of China (IJLRC), and Shanghai Sci. & Tech. and Edu. Committee (14YF1409200).

语种：英文

外文关键词：C-modified; Pd; hydrogenation; poison tolerance; thermal reduction

摘要：A coordination-assisted pyrolysis procedure was adopted to encapsulate palladium (Pd) nanoparticles in a mesoporous carbonaceous matrix. X-ray diffraction and transmission electron microscopy measurements revealed that approximately 2.5 nm nanoparticles were highly dispersed inside the well-ordered porous framework. High-resolution TEM and temperature-programmed hydride decomposition analysis demonstrated the formation of interstitial carbon in the Pd lattice. Diffuse reflectance infrared Fourier transform spectroscopy indicated that carbon species could be deposited on low-coordinated surface sites of the Pd particles. This catalyst exhibited high activity in the selective hydrogenation of cinnamaldehyde (CAL) at 80 degrees C under an H-2 pressure of 1.0 MPa (turnover frequency (TOF) of 2.4 s(-1)) to produce hydrocinnamyl aldehyde with high selectivity (HCAL; approximately 80%) in water and could be reused eight times with no dear activity loss. A trapping agent poisoning experiment using solid SH-SBA-15 revealed unobvious leaching of Pd into the solution. Exposure to thiourea with a S:Pd ratio of 0.1 resulted in slight activity and undetectable selectivity losses over the current catalyst in the selective hydrogenation of CAL at 80 degrees C under an H2 pressure of 1.0 MPa. However, a 50% activity loss was observed for commercial Pd/C. Even after an increase in the thiourea concentration to a S:Pd ratio of 3, the TOF remained at 1.9 s(-1) with a negligible effect on the HCAL selectivity. Nearly complete deactivation of Pd/C occurred upon high exposure to thiourea. DFT calculations showed that the presence of surface or subsurface carbon can enhance the poison tolerance of the encapsulated Pd catalysts. The enhanced hydrogenation activity and strong poison tolerance are consistent with the interpretation that Pd nanoparticles are modified by carbonaceous deposits.