摘要
以活性炭为催化剂载体,采用浸渍法制备Pd、Cu、Pd-Cu三种催化剂,将催化剂应用于三氟三氯乙烷(CFC-113)加氢脱氯制三氟氯乙烯(CTFE)的反应,考察Cu的引入对Pd催化剂性能的影响。对反应前后及再生的Pd-Cu催化剂进行X射线衍射(XRD)、X射线光电子能谱(XPS)、氮气吸附-脱附(BET)、氢气程序升温还原(H2-TPR)、热重(TG)、氨气程序升温脱附(NH3-TPD)等表征分析。研究表明,Pd催化剂具有较高的加氢脱氯性能,其主要产物为三氟乙烷,Cu的加入有利于提高CTFE的选择性。这应与Cu、Pd之间存在相互作用并形成合金,抑制了Pd的脱氯性能有关。反应后的催化剂存在表面结焦、反应过程中吸附Cl以及金属Cu价态变化和迁移等现象,其中表面高沸物的形成、卤元素吸附导致的金属迁移和Cu-Pd相互作用的改变是Pd-Cu催化剂失活的主要原因。
Using activated carbon as the catalyst carrier,we prepared three catalysts of Pd/AC,Cu/AC and Cu-Pd/AC by impregnation method.The catalysts were applied to trifluorochloroethane hydrodechlorination to prepare trifluorochloroethylene.The effect of Cu introduction on the performance of the catalysts was studied.The properties of fresh,spent,and regenerated Pd-Cu catalysts were measured using XRD,XPS,BET,H2-TPR,TG and NH3-TPD.The results showed that the Pd catalyst had good hydrodechlorination performance,and the main product was trifluoroethane.The addition of Cu was beneficial to improve the selectivity of chlorotrifluoroethylene.This should be related to the interaction between Cu and Pd and the formation of alloys,which inhibited the dechlorination.Surface coking,adsorption of Cl,and the change and migration of the valence state of the metal Cu were observed on the catalyst.The formation of high boiling species on surface,metal migration due to halogen adsorption,and changes in Cu-Pd interaction were the main reasons for the deactivation of Pd-Cu catalysts.
作者
陆子薇
廖湘洲
粟小理
隋志军
LU Ziwei;LIAO Xiangzhou;SU Xiaoli;SUI Zhijun(State Key Laboratory of Chemical Engineering,East China University of Science and Technology,Shanghai 200237,China;Technology Research Institute of Shanghai Huayi Group,Shanghai 200241,China)
出处
《化工进展》
EI
CAS
CSCD
北大核心
2023年第1期282-288,共7页
Chemical Industry and Engineering Progress
基金
上海市2021年度“科技创新行动计划”(21XD1432200)。
关键词
加氢
脱氯
三氟氯乙烯
催化剂
失活
hydrogenation
dechlorination
chlorotrifluoroethylene
catalyst
deactivation
