镧和铈改性CuNi/Al_2O_3催化剂上乙炔的选择加氢

Selective hydrogenation of acetylene on CuNi/Al_2O_3 catalyst

采用浸渍法制备了稀土镧和铈改性的CuNi/Al2O3催化剂,研究了稀土负载量对催化剂活性和选择性的影响,并研究了催化剂的还原性能。结果表明:La和Ce的存在均降低了活性相CuO和NiO的还原温度,使改性催化剂具有更高的催化活性,但催化剂上乙烯的选择性则是Ce改性催化剂高于La改性催化剂,当CeO2含量为1%时,CeCuNi/Al2O3催化剂上乙炔转化率达到98%,乙烯选择性和收率则分别达到84%和82.3%,比未改性的CuNi/Al2O3催化剂上乙烯收率高16.4%,显示出CeO2改性CuNi/Al2O3催化剂的优异性能。

The CuNi/Al2O3 catalyst modified by rare earth lanthanum and cerium oxides for selective hydro- genation of acetylene was prepared by impregnation method. The influences of lanthanum loading and cerium load- ing on the activity and selectivity of CuNi/Al2O3 catalyst were investigated, respectively. Reduction property of the catalyst was also studied. The experimental results showed that lanthanum and cerium in CuNi/Al2O3 catalyst re- duce the reduction temperature of active phases of CuO and NiO, which causes the modified catalyst to possess very high activity. Ce-modified catalyst CeCuNi/Al2O3 has higher ethylene selectivity than La-modified one. When the content of CeO2 is 1%, the conversion of acetylene will be up to 98%, while the selectivity and yield of ethy- lene on the modified catalyst CeCuNi/Al2O3 can reach 84% and 82.3%, respectively. The yield of ethylene is in- creased by 16.4% as compared with CuNi/Al2O3 has showed CeO2 modified catalyst＇s perfect performance.