Oxygen and nitrogen-doped metal-free carbon catalysts for hydrochlorination of acetylene  

作　　者：Tongtong Zhang Jia Zhao Jiangtao Xu Jinhui Xu Xiaoxia Di Xiaonian Li 

机构地区：[1]Industrial Catalysis Institute of Zhejiang University of Technology, Hangzhou 310014, China

出　　处：《Chinese Journal of Chemical Engineering》2016年第4期484-490,共7页中国化学工程学报（英文版）

基　　金：Supported by the National Natural Science Foundation of China(21476207);the National Basic Research Program of China(2011CB710800)

摘　　要：Activated carbon was tested as metal-free catalyst for hydrochlorination of acetylene in order to circumvent the problem of environment pollution caused by mercury and high cost by noble metals. Oxygen-doped and nitrogen-doped activated carbons were prepared and characterized by XPS, TPD and N2 physisorption methods. The influences of the surface functional groups on the catalytic performance were discussed base on these results. Among all the samples tested, a nitrogen-doped sample, AC-n-US00, exhibited the best performance, the acety- lene conversion being 92% and vinyl chloride selectivity above 99% at 240 ~C and C2H2 hourly space velocity 30 h- 1. Moreover, the AC-n-US00 catalyst exhibited a stable performance during a 200 h test with a conversion of acetylene higher than 76% at 210 ~C at a C2H2 hourly space velocity 50 h 1. In contrary, oxygen-doped catalyst had lower catalytic activities. A linear relationship between the amount of pyrrolic-N and quaternary-N species and the catalytic activity was observed, indicating that these nitrogen-doped species might be the active sites and the key in tuning the catalytic performance. It is also found that the introduction of nitrogen species into the sample could significantly increase the adsorption amount of acetylene. The deactivation of nitrogen- doped activated carbon might be caused by the decrease of the accessibility to or the total amount of active sites.Activated carbon was tested as metal-free catalyst for hydrochlorination of acetylene in order to circumvent the problem of environment pollution caused by mercury and high cost by noble metals. Oxygen-doped and nitrogen-doped activated carbons were prepared and characterized by XPS, TPD and N2 physisorption methods.The influences of the surface functional groups on the catalytic performance were discussed base on these results.Among all the samples tested, a nitrogen-doped sample, AC-n-U500, exhibited the best performance, the acetylene conversion being 92% and vinyl chloride selectivity above 99% at 240 °C and C2H2 hourly space velocity30 h-1. Moreover, the AC-n-U500 catalyst exhibited a stable performance during a 200 h test with a conversion of acetylene higher than 76% at 210 °C at a C2H2 hourly space velocity 50 h-1. In contrary, oxygen-doped catalyst had lower catalytic activities. A linear relationship between the amount of pyrrolic-N and quaternary-N species and the catalytic activity was observed, indicating that these nitrogen-doped species might be the active sites and the key in tuning the catalytic performance. It is also found that the introduction of nitrogen species into the sample could significantly increase the adsorption amount of acetylene. The deactivation of nitrogendoped activated carbon might be caused by the decrease of the accessibility to or the total amount of active sites.

关 键 词：Acetylene hydrochlorinationActivated carbonSurface chemistryOxygenated groupNitrogen-doped 

分 类 号：TQ424.1[化学工程] O643.36[理学—物理化学]