利用浸渍法和共沉淀法得到La-Ni改性的硫酸化氧化锆催化剂,并对其在正丁烷异构化反应的性能进行考察.结果表明:改性方法对其催化异构化反应性能具有显著影响;用共沉淀法制得的催化剂在不降低异丁烷收率的前提下,通过减少副反应的发生来提高异丁烷选择性;而用浸渍法得到的催化剂表现出很高的异丁烷选择性,但正丁烷转化率显著降低,造成异丁烷收率也明显降低.利用Py-FTIR、低温氮气吸附-脱附、红外硫碳分析等表征,发现La-Ni改性处理对正丁烷在催化剂表面氧化脱氢能力影响不大,但对质子活化途径影响较大.共沉淀得到的催化剂表面超强B酸位密度的适度降低有利于提高单分子异构化途径所占的比例,而浸渍法所得催化剂表面B酸密度的显著降低导致其正丁烷转化受阻.%The La/Ni modified sulfated zirconia catalyst was prepared by impregnation and co-precipitation method,and its structure-activity relationship in n-Butane isomerization was investigated.The results show that the modification method has a remarkable influence on the isomerization performance.The catalyst prepared by co-precipitation method improved the selectivity to isobutane by reducing the side reaction without decreasing in the yield of isobutane,while the impregnation promoted the selectivity to isobutane,but strikingly decreased the conversion of n-butane,leading to an obvious decrease in the yield of isobutane.The catalysts were characterized by Py-FTIR,low temperature nitrogen absorption and desorption,infrared sulfur and carbon analysis.It was found that La/Ni modified treatment had little influence on the oxidative activation of n-butane,but significantly influence its protonation activation pathway.The moderately decrease in the density of surface strong Brφnsted acid by co-precipitation enhances the proportion of monomolecular isomerization pathway.However,the impregnation modification leads to a remarkable decrease in the density of strong Brφnsted acid on the surface,as well as n-butane conversion.
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