负载双金属磷酸铝分子筛的裂化活性

用单浸溃和双浸溃法制得 Mo/AlPO_4-5、Ni/ALPO_4-5、MoNi/AIPO_4-5、NiMo/AIPO_4-5和(MoNi)/AIPO_4-5分子筛催化剂。测试它们的裂化活性、电子顺磁共振谱图和透射电子显微图,结果表明,高温预处理对 Ni/AIPO_4-5和 Mo/AIPO4-5的裂化活性有着相反的作用。从 EPR信号得知,MO~(5+)使 Mo/AIPO_4-5裂化反应的活性增加。镍对其活性影响很大。对于负载双金属磷酸铝分子筛,镍钼浸溃的先后次序以及样品中 NiO/MoO_3比值的大小对裂化活性存在着一定的规律性。负载型分子筛催化剂的催化活性主要是由后浸渍的金属决定。

The Cracking Activity of Supported Bimetal Aluminophosphate Molecular Sieves

Gracking activity,electron paramagnetic resonance spectra and transmission electron micrograph of Mo/AlPO_4-5,Ni/AlPO_4-5,MoNi/AlPO_4-5,NiMo/AlPO_4-5 and (MoNi)/AlPO_4-5 molecular sieves prepared by single or double impregnation were studied.Results demonstrate that high temperature pretreament of Ni/ AlPO_4-5 and Mo/AlPO_4-5 shows opposite effect in regard to cracking activity. EPR signals show that Mo~(+5) raised cracking activity of Mo/AlPO_4-5.Nickel strong- ly affects the activity of Mo/AlPO_4-5 also.There exists correlation between crack- ing aotivity and the order of impregnation of nickel and molybdenum as well as the ratio NiO/MoO_3 in the samples.The catalytic activity of supported bimetal aluminophosphate molecular sieves is mainly determined by the last impregnated metal.