Abstract: There is provided a mixed catalyst of ZSM-5 and ZSM-12. Alkylbenzenes, especially heavy aromatic bottoms from cumene production, may be cracked over this mixed catalyst.

Abstract: Alumina-composited zeolite catalysts are activated by contact with an aqueous ammonium solution under ammonia gas pressure such that a pH of at least about 8 is maintained in the solution. The treated zeolite may thereafter be calcined without prior ammonium-exhange to provide the zeolite in the hydrogen form. Catalysts which are activated in this manner are useful for converting alcohols and/or ethers to hydrocarbons including aromatics.

Abstract: Alumina-composited zeolite catalysts are activated by contact with an aqueous ammonium solution under ammonia gas pressure such that a pH of at least about 10 is maintained in the solution. The treated zeolite may thereafter be calcined without prior ammonium-exchange to provide the zeolite in the hydrogen form.

Abstract: Alumina-composited zeolite catalysts are activated by contact with an aqueous ammonium solution under ammonia gas pressure such that a pH of at least about 8 is maintained in the solution. The treated zeolite may thereafter be calcined without prior ammonium-exchange to provide the zeolite in the hydrogen form.

Abstract: There is disclosed a process for recovering olefin monomers, e.g., C.sub.3 -C.sub.10 alpha-olefins, from a vent gas of a vapor phase process for polymerizing olefins. The method comprises passing the vent gas, obtained by purging a resin produced in the polymerization process with an inert gas, such as nitrogen, into contact with an adsorbent to effect the adsorption of an olefin monomer. Subsequently, the adsorbed monomer is removed by contacting the adsorbent with a second monomer having lower molecular weight than the adsorbed monomer.

Abstract: A process is disclosed for converting a methanol-containing feed to a light olefin-containing product over a ZSM-12 zeolite catalyst, preferably modified by incorporation of either magnesium, manganese or both magnesium and manganese. By using such Mg and/or Mn-modified ZSM-12 zeolite catalysts, methanol and/or methyl ether can be converted to an olefin-containing hydrocarbon product enriched in C.sub.2 to C.sub.4 olefins and especially enriched in the particular light olefin propylene.

Abstract: Carbon molecular sieves are used in the oxidative dehydrogenation of alkyl aromatic compounds, for example, in the dehydrogenation of ethylbenzene to styrene.

Abstract: There is provided a mixed catalyst of ZSM-5 and ZSM-12. Alkylbenzenes, especially heavy aromatic bottoms from cumene production, may be cracked over this mixed catalyst.

Abstract: There is provided a mixed catalyst of ZSM-5 and ZSM-12. Alkylbenzenes, especially heavy aromatic bottoms from cumene production, may be cracked over this mixed catalyst.

Abstract: A process for converting a methanol feed to light olefins over a zeolite catalyst comprising at least some crystalline aluminosilicate zeolitic material having a Constraint Index of about 1 to 12 and a silica/alumina mole ratio of at least about 12, e.g., ZSM-5, in the presence of an aldehyde-containing diluent comprising formaldehyde, acetaldehyde or mixtures thereof, under methanol conversion conditions. By using such a ZSM-5 type zeolite catalyst and an aldehyde-containing diluent, methanol can be converted to an olefin-containing hydrocarbon product enriched in C.sub.2 to C.sub.4 olefins such as ethylene.