Towards a greener approach for the preparation of highly active gold/carbon catalyst for the hydrochlorination of ethyne
Towards a greener approach for the preparation of highly active gold/carbon catalyst for the hydrochlorination of ethyne
复制标题
寻找一种更绿色的方法来制备用于乙炔氢氯化的高活性金/碳催化剂
DOI：
10.1016/j.jcat.2018.06.030
复制
发表时间：
2018-09-01
影响因子：
7.3
通讯作者：
Li, Xiaonian
中科院分区：
文献类型：
--
作者：
Zhao, Jia;Wang, Bolin;Li, Xiaonian
活性炭载金（Au/AC）材料是一种很有前途的乙炔氢氯化催化剂。制备活性、稳定的Au/AC无王水乙炔氢氯化催化剂仍然是一个重大的挑战。一种新的催化剂制备协议，包括浸渍使用H2 O2/HCl混合物的高活性Au/AC催化剂，主要包括单中心阳离子Au物种，如系统的X射线光电子能谱（XPS），程序升温还原（TPR）分析和透射电子显微镜（TEM）成像所确定的。此外，通过程序升温脱附（TED）分析的Au-C界面的评价表明，活性炭的氧化由H2 O2/HCl混合物，这产生表面含氧官能团（SOG），是形成活性Au/AC催化剂的关键步骤。的结构测定和全面的实验证据允许密度泛函理论（DFT）预测，单中心的阳离子AuCl物种通过SOG通过-O-键稳定的Au催化乙炔氢氯化反应的有效活性位点。此外，这些催化剂可以重复使用几次，与H2 O2/HCl混合物处理后的性能变化可以忽略不计。因此，H2 O2/HCl混合物被设想为一个可行的，绿色替代有毒的王水制备Au/AC催化剂乙炔氢氯化。(C)2018爱思唯尔公司All rights reserved.
Gold on activated carbon (Au/AC) materials are promising alternative catalysts for ethyne hydrochlorination. The preparation of active, stable Au/AC catalysts without aqua regia for ethyne hydrochlorination remains a significant challenge. A novel catalyst preparation protocol involving impregnation using a H2O2/HCl mixture is established for highly active Au/AC catalysts comprising primarily of single-site cationic Au species, as identified by systematic X-ray photoelectron spectroscopy (XPS), temperature programmed reduction (TPR) analyses and transmission electron microscopy (TEM) imaging. In addition, evaluation of the Au-C interface by temperature-programmed desorption (TAD) analyses showed that the oxidation of activated carbon by the H2O2/HCl mixture, which creates surface oxygen-containing functional groups (SOGs), is a crucial step for the formation of active Au/AC catalysts. The structure determination and comprehensive experimental evidence allow density functional theory (DFT) to predict that single-site cationic AuCl species stabilized by SOGs via -O- linkages are efficient active sites for Au-catalyzed ethyne hydrochlorination. In addition, these catalysts can be reused for several times with negligible changes in performance after treatment with the H2O2/HCl mixture. The H2O2/HCl mixture is thus envisioned as a viable, green alternative to toxic aqua regia for the preparation of Au/AC catalysts for ethyne hydrochlorination. (C) 2018 Elsevier Inc. All rights reserved.