1
Ashim Kumar Ghosh: Aromatic alkylation process. Fina Technology, Pamela S Smith, William D Jackson, M Norwood Cheairs, May 25, 1999: US05907073 (39 worldwide citation)

A process for the alkylation of an aromatic substrate over a molecular sieve zeolite catalyst involving supplying an aromatic substrate to a reaction zone containing the catalyst. The molecular sieve catalyst is an effective aromatic alkylation catalyst and comprises a modified zeolite beta alkylati ...


2
James T Merrill, James R Butler, Ashim Kumar Ghosh: Gas phase alkylation with split load of catalyst. Fina Technology, Pamela S Smith, William D Jackson, M Norwood Cheairs, May 2, 2000: US06057485 (25 worldwide citation)

Ethylbenzene is produced by alkylation over a split load of monoclinic silicalite alkylation catalysts having different silica/alumina ratios. A feedstock containing benzene and ethylene is applied to a multi-stage alkylation reaction zone having a plurality of series-connected catalyst beds. At lea ...


3
Ashim Kumar Ghosh, James T Merrill, James R Butler: Gas phase alkylation-liquid phase transalkylation process. Fina Technology, Pamela S Smith, William D Jackson, M Norwood Cheairs, December 8, 1998: US05847255 (23 worldwide citation)

Process for the production of ethylbenzene by alkylation over a silicalite alkylation catalyst with the subsequent transalkylation of diethylbenzene with the alkylation catalyst and conditions selected to retard xylene production and also heavies production. A feedstock containing benzene and ethyle ...


4
James R Butler, Ashim Kumar Ghosh: Gas phase alkylation method and catalyst. Fina Technology, John K Abokhair, M Norwood Cheairs, July 18, 2000: US06090991 (22 worldwide citation)

Ethylbenzene is produced by alkylation over monoclinic silicalite catalysts having a weak acid site concentration of less than 50 micromoles per gram. A feedstock containing benzene and ethylene is applied to an alkylation reaction zone having at least one catalyst bed containing a monoclinic silica ...


5
James R Butler, Ashim Kumar Ghosh: Catalysts with low concentration of weak acid sites. Fina Technology, John K Abokhair, Jim D Wheelington, July 31, 2001: US06268305 (20 worldwide citation)

Ethylbenzene is produced by alkylation over monoclinic silicalite catalysts having a weak acid site concentration of less than 50 micromoles per gram. A Feed stock containing benzene and ethylene is applied to an alkylation reaction zone having at least one catalyst bed containing a monoclinic silic ...


6
Ashim Kumar Ghosh, James T Merrill, James R Butler: Gas phase alkylation-liquid phase transalkylation process. Fina Technology, William D Jackson, Jim D Wheelington, April 24, 2001: US06222084 (20 worldwide citation)

Process for the production of ethylbenzene by alkylation over a silicalite alkylation catalyst with subsequent transalkylation of diethylbenzene with the alkylation catalyst and conditions selected to retard xylene production and also heavies production. Benzene and ethylene are applied to a multi-s ...


7
Ashim Kumar Ghosh: Zeolite catalyst with enhanced dealkylation activity and method for producing same. Fina Technology, William D Jackson, Pamela S Smith, M Norwood Cheairs, August 1, 2000: US06096938 (20 worldwide citation)

An improved zeolite catalyst having enhanced dealkylation activity is provided. The catalyst is prepared by incorporating fluorine into the zeolite structure. In another embodiment, a transition element such as nickel is additionally incorporated into the zeolite structure. The process for producing ...


8
Ashim Kumar Ghosh, Neeta Kulkarni, Pamela Harvey, Roncalli J Twomey: Hydrothermal treatment of phosphorus-modified zeolite catalysts. Saudi Basic Industries Corporation, Grady K Bergen, Jim D Wheelington, Griggs Bergen, December 4, 2007: US07304194 (19 worldwide citation)

A method of treating a ZSM-5-type zeolite catalyst is carried out by treating a ZSM-5 zeolite catalyst having a silica/alumina mole ratio of at least about 200 with a phosphorus compound. The phosphorus-treated ZSM-5 zeolite catalyst is calcined and steamed. Steaming of the catalyst is carried out a ...


9
Ashim Kumar Ghosh: Zeolite catalyst with enhanced dealkylation activity and method for producing same. Fina Technology, Pamela S Smith, William D Jackson, M Norwood Cheairs, November 23, 1999: US05990031 (19 worldwide citation)

An improved zeolite catalyst having enhanced dealkylation activity is provided. The catalyst is prepared by incorporating fluorine into the zeolite structure. In another embodiment, a transition element such as nickel is additionally incorporated into the zeolite structure. The process for producing ...


10
Ashim Kumar Ghosh, Gopalakrishnan Juttu, Pamela Harvey, Neeta Kulkarni: Method of modifying zeolite catalyst. Saudi Basic Industries Corporation, Grady K Bergen, Jim D Wheelington, October 23, 2007: US07285511 (17 worldwide citation)

A method of modifying a zeolite catalyst to increase para-xylene selectivity of the zeolite catalyst in toluene methylation reactions is provided. The method includes forming a slurry of a ZSM-5-type zeolite and an aqueous solution of a phosphorus compound. Water is removed from the slurry to provid ...