| 摘要 |
PURPOSE:To isomerize xylenes in a high isomerization yield by bringing a raw material mixture contg. xylene isomer into vapor contact with a platinum modified catalyst compsn. contg. crystalline alumino silicate zeolite subjected to ion exchanging with Mg or Ca. CONSTITUTION:The crystalline alumino silicate zeolite expressed by the formula I (the formula is expressed in the form of oxide in an anhydrous state, wherein M is Mg<2+> or Ca<2+>, N is >=1 kinds cations of valency n except alkaline earth metals. X; 0.1-1:y; 15-200) and platinum of the under-mentioned amt. are used as the essential active components of this catalyst compsn.: The amt. corresponding to 1-2,000 R expressed by the formula II (m1, m2, m3, m4 are respectively the mol. wts. of MO, N2/nO, Al2O3, SiO2 in the formula I , m is the atomic weight of platinum, W is weight% of platinum based on the weight of the above-described zeolite). This catalyst compsn. is formulated to provide 0.1- 0.9 1, 3, 5-trimethyl benzene adsorptivity and >=60 ethyl benzene/xylene reaction selectivity. |
