文献类型：期刊文献

英文题名：Carbonization of Chitosan in Palladium-Chitosan/ Montmorillonite Composites to Prepare Novel Heterogeneous Catalysts for Heck Reactions

作者：Wang, Yudong[1];Liu, Qi[1];Xu, Mengdie[1];Shu, Guiqing[1];Jiang, Minjuan[1];Fei, Gangxuan[1];Zeng, Minfeng[1]

机构：[1]Shaoxing Univ, Zhejiang Key Lab Alternat Technol Fine Chem Proc, Shaoxing 312000, Peoples R China

年份：2017

卷号：56

期号：9

起止页码：670

外文期刊名：JOURNAL OF MACROMOLECULAR SCIENCE PART B-PHYSICS

收录：SCI-EXPANDED(收录号：WOS:000414210700005)、、EI(收录号：20174104251485)、Scopus(收录号：2-s2.0-85030653863)、WOS

基金：The authors acknowledge the financial support from the National Natural Science Foundation of China (Grant number11475114).

语种：英文

外文关键词：carbonization; catalysis; chitosan; montmorillonite

外文摘要：Palladium-carbon/montmorillonite (Pd-C/MMT) heterogeneous catalysts were prepared by carbonization of chitosan in palladium-chitosan/montmorillonite (Pd-CS/MMT) composites under a N-2 atmosphere. The main purpose of this study was to determine the effects of the carbonization temperature (250, 450, and 650 degrees C) on the material microstructure and its catalytic performance. X-ray diffraction patterns revealed that the formation of an intercalation of the carbonaceous material between the clay mineral layers which was also confirmed by Fourier transform infrared spectra results. The N content of the Pd-C/MMT catalyst decreased as the carbonization temperature was increased. Thermogravimetry curves revealed that the thermal stability of the Pd-C/MMT catalyst increased obviously as the carbonization temperature was increased. Pd nanoparticles, sized at about 20nm, were mainly dispersed on the surface of the MMT, as observed by high-resolution transmission electron microscopy (HR-TEM). The prepared Pd-C/MMT catalysts had good catalytic activity when applied in Heck coupling reactions of aromatic halides and alkenes to produce aryl olefins. The relations between the recyclability and the material composition are discussed.