abstract |
Described are catalyst compositions comprising a HAMS-1B crystalline borosilicate molecular sieve, the majority of the crystallites of which are between about 1 micron and about 15 micron in largest diameter, incorporated into an inorganic matrix, which have been impregnated with a small amount of a magnesium compound, said impregnated compositions having improved para-selectively for toluene methylation to xylene. Such impregnated compositions, when used for the methylation of toluene using methanol or dimethylether, yield a xylene product containing a very high proportion of the para isomer compared to corresponding unimpregnated or magnesium compound-impregnated borosilicate-based compositions containing standard size (0.2 mu to 0.5 mu ) borosilicate molecular sieve crystallites. |