摘要
采用4种方法制备了VMgO催化剂样品(w(V2O5)=30%,w(MgO)=70%),并将其用于正丁烷氧化脱氢气固相反应.结果表明,MgO经蒸馏水回流和焙烧处理后再用NH4VO3溶液浸渍所制得的VMgO,对正丁烷氧化脱氢生成丁烯和丁二烯反应具有更好的催化性能.这是由于用该法制备的VMgO催化剂中存在较多的Mg3V2O8物种.通过添加Ni对VMgO催化剂进行了改性.结果表明,适量添加Ni(n(Ni)/n(V)=0.3)有利于催化剂中Mg3V2O8的生成,而Ni以Ni3V2O8的形态存在.由此明显改善了VMgO催化剂对正丁烷氧化脱氢生成丁烯和丁二烯反应的催化性能.
The VMgO catalyst samples （ω（V2O5）= 30%, ω（MgO）= 70% ） were prepared by four different methods, characterized by XRD and FT-IR and used in oxidative dehydrogenation of n-butane. The VMgO catalyst sample prepared by impregnation using MgO as a support, which was treated in refluxing distilled water followed by calcination at 500 ℃ , showed higher activity and selectivity in the reaction. This was attributed to more Mg-orthovanadate （Mg3V2O8 ） and less Mg2V2O7 and V2O5 species in the sample. The VMgO catalyst was further modified with nickel component. By doping the VMgO catalyst with nickel at n （Ni）/n （V）= 0.3, the selectivity for butene and butadiene in the reaction was increased from 46.7 % at n-butane conversion of 18.3 % to 51.2% at n-butane conversion of 20.3%. The Ni-VMgO catalyst contained more Mg3V2O8 and less Mg2V2O7 species than the VMgO catalyst.
出处
《催化学报》
SCIE
CAS
CSCD
北大核心
2005年第8期650-654,共5页
关键词
正丁烷
氧化脱氢
丁烯
丁二烯
氧化钒
氧化镁
复合氧化物
氧化镍
n-butane, oxidative dehydrogenation, butene, butadiene, vanadium oxide, magnesium oxide, composite oxide, nickel oxide
