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少量Ti对Pt/Al_2O_3所起的作用,总的趋势是随着Ti量的增加使环戊烷氢解反应活性中心的密度减少,活性频率下降,活化能和指前因子增加并互为补偿效应。这可能是因为催化剂还原时生成的Ti~(<4+)或Ti~0对Pt所起的集团效应和电子配位体效应的结果。另外,当催化剂中Ti的含量在0.25—1.0％(重)时,上述各种参数随Ti量而变化的幅度不大,这可能是因为催化剂中未被还原的Ti~(4+)具有增强Pt的活性的作用,因此它部分抵消了Ti~(<4+)或Ti~0所起的减弱Pt的活性的作用。
The effect of a small amount of Ti on Pt / Al_2O_3 shows that the overall trend is that as the amount of Ti increases, the density of cyclopentane hydrogenolysis reaction centers decreases, the activity frequency decreases, and the activation energy and pre-exponential factors increase and complement each other . This may be attributed to the group effect of Ti ~ (<4+) or Ti ~ 0 on Pt caused by catalyst reduction and the effect of electron ligand. In addition, when the content of Ti in the catalyst is 0.25-1.0% by weight, the above parameters do not vary greatly with the amount of Ti, which may be because the unreduced Ti ~ (4+) in the catalyst has enhanced Pt activity, so it partially offset the effect of Ti ~ (<4+) or Ti ~ 0 to weaken Pt activity.