CuCl_2/13X催化剂在乙炔氢氯化反应中的应用

Performance of CuCl_2/13X catalyst in acetylene hydrochlorination

将13X分子筛与氯化铜活性组分相结合,制备了稳定性和选择性优异的乙炔氢氯化反应催化剂CuCl_2/13X.系统考察了氯化铜负载量、反应温度、反应气空速、预处理温度对CuCl_2/13X催化剂反应性能的影响.发现经300℃预处理后,在反应温度220℃和乙炔空速30 h^(-1)条件下,氯化铜负载量25%的25CuCl_2/13X催化剂具有最佳的反应性能,乙炔转化率高于78%、氯乙烯选择性超过99%,反应16 h后催化剂的活性和选择性稳定且略有升高.运用低温氮气物理吸附、穿透实验、热重分析以及X射线衍射分析等手段对催化剂及反应过程进行了表征.分析了反应条件对结果产生影响的原因,并发现催化剂对HCl的强吸附性能和13X与氯化铜之间的相互促进作用,是CuCl_2/13X性能优于CuCl_2/AC的原因.

1Catalysts CuCl2/13 X were prepared from the combination of 13 X zeolite and copper chloride, and they exhibited excellent stability and vinyl chloride monomer（VCM） selectivity in acetylene hydrochlorination. The effects of copper chloride loading amount, reaction temperature, acetylene space velocity and pretreatment temperature on CuCl2/13 X catalyst＇s catalytic performance were investigated. It was found that after pretreatment under 300 ℃25 CuCl2/13 X displayed the best catalytic performance at reaction temperature of 220 ℃ and acetylene space velocity of30 h^（-1）, and its acetylene conversion and VCM selectivity was higher than 78% and 99%, respectively, and the catalyst＇s reactivity slightly increased after 16-h reaction. Different techniques including low temperature physical adsorption of nitrogen, breakthrough experiment, thermogravimetric analysis（TG）, differential scanning calorimetry（XRD） and Xray diffraction（XRD） were employed to characterize the catalysts. The results demonstrated that the strong HCl adsorption ability of CuCl2/13 X catalyst and the enhancement between 13 X and copper chloride explained why the catalytic performance of CuCl2/13 X was better than that of CuCl2/AC.