1995 Volume 21 Issue 6 Pages 1096-1103
We have developed methods of preventing catalytic deactivation on isomerization of 1-methylnaphthalene over HY-zeolite, by eliminating part of the aluminum from zeolite and adding a small amount of methyltetralin to the starting material. As a result of analysis of the coking behavior, a quantitative estimation method of catalytic life, which is necessary for the design of the catalyst, specification and reaction conditions, has been obtained. Because it was found that specific activity of the catalyst depended on the extent of coke deposition, accelerating the rate of coking by rasing the concentration of methylnaphthalene in the feed gas was effective for exact and rapid estimation. Consequently, it has been predicted that the desired yield of 2-methylnaphthalene, 60%, is maintained for one year or more, when HY-zeolite with a 24.32Å unit cell constant is used and 2-3% of methyltetralin is added to starting the 1-methylnaphthalene.