Abstract: There is provided a catalyst and a process for converting methanol or dimethyl ether to a product containing C.sub.2 to C.sub.4 olefins. The catalyst comprises a porous crystalline material having a Diffusion Parameter for 2,2-dimethylbutane of about 0.1-20 sec.sup.-1 when measured at a temperature of 120.degree. C. and a 2,2-dimethylbutane pressure of 60 torr (8 kPa). In addition, the catalyst is characterized by a hydrothermal stability such that, after steaming the catalyst at 1025.degree. C. for 45 minutes in 1 atmosphere steam, the catalyst exhibits a methanol conversion activity of at least 50% when contacted with methanol at a methanol partial pressure of 1 atmosphere, a temperature of 430.degree. C. and 0.5 WHSV. The porous crystalline material is preferably a medium-pore zeolite, particularly ZSM-5, which contains phosphorus and has been severely steamed at a temperature of at least 950.degree. C.

Abstract: There is provided a process for converting methanol and/or dimethyl ether to a product containing C.sub.2 to C.sub.4 olefins which comprises the step of contacting a feed which contains methanol and/or dimethyl ether with a catalyst comprising a porous crystalline material, said contacting step being conducted in the presence of an aromatic compound under conversion conditions including a temperature of 350.degree. C. to 480.degree. C. and a methanol partial pressure in excess of 10 psia (70 kPa), said porous crystalline material having a pore size greater than the critical diameter of the aromatic compound and the aromatic compound being capable of alkylation by the methanol and/or dimethyl ether under said conversion conditions.

Abstract: This is a process for upgrading a petroleum naphtha fraction. The naphtha is subjected to reforming and the reformate is cascaded to a benzene and toluene synthesis zone over a benzene and toluene synthesis catalyst comprising a molecular sieve of low acid activity. The preferred molecular sieve is steamed ZSM-5. The benzene and toluene synthesis zone is operated under conditions compatible with the conditions of the reformer such as pressures of above about 50 psig (446 kPa) and temperatures above about 800.degree. F. (427.degree. C). In one aspect of the invention, the benzene and toluene synthesis catalyst includes a metal hydrogenation component such as cobalt, nickel, platinum or palladium. In one mode of operation, the benzene and toluene synthesis catalyst replaces at least a portion of the catalyst of the reformer. The process produces a product containing an increased proportion of benzene and toluene, and a reduced proportion of C8 aromatics, particularly ethylbenzenes, as compared to the reformate.