Ring opening of decalin over zeolitesII. Activity and selectivity of platinum-modified zeolites
作者:David Kubička、Narendra Kumar、Päivi Mäki-Arvela、Marja Tiitta、Vesa Niemi、Hannu Karhu、Tapio Salmi、Dmitry Yu. Murzin
DOI:10.1016/j.jcat.2004.07.015
日期:2004.10.25
platinum-modified zeolites (Beta, Y, Mordenite) were investigated in the ring opening of decalin at 473–543 K in the presence of hydrogen. In the course of decalin transformation, skeletal isomerization, stereoisomerization, ring opening, and cracking took place. The presence of platinum resulted in an enhancement of isomerization and ring-opening rates, as compared to the proton-form zeolites. The isomerization
在氢存在下,萘烷在473–543 K的开环中研究了铂改性沸石(β,Y,丝光沸石)的活性和选择性。在萘烷转化的过程中,发生了骨架异构化,立体异构化,开环和开裂。与质子型沸石相比,铂的存在导致异构化和开环速率的提高。异构化和开环速率分别增加了3倍和5倍。发现氢气压力抑制了次级反应并防止了催化剂失活。异构化和开环反应不受氢的存在的影响。观察到催化剂失活的变化,并归因于有机沉积物的不同位置。铂和布朗斯台德酸位点之间的相互作用表明,铂微晶部分位于所研究沸石的通道中。这些相互作用的结果是,在铂改性的沸石上,与相应的母体沸石相比,在可比较的转化率下,布朗斯台德酸位点的强度降低,因此形成的裂化产物更少。