Mobil Oil Corporation

Exxon Research and Engineering Company

David S Shihabi

Clarence D Chang

Scott S Han

Sanjay B Sharma

David O Marler

Scott A Stevenson

John P McWilliams

Robert P Absil

James C Vartuli

Richard F Socha

Emmerson Bowes

Nai Y Chen

Jose G Santiesteban

Gary J Green

Thomas R Forbus, Jr

Costandi A Audeh

Paul G Rodewald, Jr

Cynthia T-w Chu

Paul B Weisz

Maria D Farnos

Tsoung Y Yan

Thomas F Degnan

Mae K Rubin

Daria N Lissy

Hye Kyung Timken

John D Lutner

Mohsen N Harandi

Ralph M Dessau

Philip Jay Angevine

Paul H Schipper

Pochen Chu

Charles T Kresge

Jeffrey S Beck

Werner O Haag

William E Garwood

Joseph N Miale

Joseph A Herbst

Sharon B McCullen

Rene B LaPierre

Catherine S Chen

Albert B Schwartz

Ajit V Sapre

Guenter H Kuehl

Donald J Klocke

Philip Varghese

John Dixon

Roland H Heck

Chwan P Kyan

Eric J Scott

Robert L Smith

Jeevan S Abichandani

Steven E Wentzek

Robert W Bortz

Rene B La Pierre

Donna M Mitko

Frank Thomas Diguiseppi

A shape-selective catalyst comprises a synthetic porous crystalline material having the structure of ZSM-5 and a composition involving the molar relationship: X O :(n)YO , wherein X is a trivalent element, such as aluminum, boron, iron and/or gallium, preferably aluminum; Y is a tetravalent element such as silicon and/or germanium, preferably silicon; and n is greater than about 12, and wherein the crystals have a major dimension of at least about 0.5 micron and a surface YO /X O ratio which is no more than 20% less than the bulk YO /X O ratio of the crystal. The crystals have a diffusion-modifying surface coating of a refractory material such as silica or coke. The catalyst is useful in a wide variety of selective hydrocarbon conversion processes, particularly the selective disproportionation of toluene to para-xylene.

Shape selective zeolite catalyst and its use in aromatic compound conversion

MCM-56 and MCM-49 have been demonstrated to be effective catalysts for the reduction of nitrogen oxide (NO.sub.x) emissions in a net oxidizing environment such as Selective Catalytic Reduction or lean burn engine exhaust applications. MCM-56 and MCM-49 can be utilized as a component of a spherical or cylindrical catalyst particle or as a wash coat on a ceramic or metallic monolith. Optionally, a transition metal such as copper, can be added to the catalyst for improved activity.

Catalytic reduction of nitrogen oxide emissions with MCM-49 and MCM-56

Large crystal ZSM-5, its synthesis and use

This invention is directed to a catalyst that comprises (i) an acidic solid oxide component comprising an oxide of a Group IVB metal modified with an anion or oxyanion of a Group VIB metal, and (ii) a Group IB metal or metal oxide component. This catalyst may be used, for example, to isomerize paraffins.

Catalyst having an acidic solid oxide component and a group IB metal or

Oxides of nitrogen (NO.sub.x) emissions from an FCC regenerator are reduced by operating the regenerator in partial CO burn mode to produce flue gas with more CO than O.sub.2 and with NO.sub.x precursors. This flue gas is then enriched with controlled amounts of oxygen and charged over catalyst, preferably Group VIII noble metal on a support, to convert most NO.sub.x precursors to nitrogen. Flue gas may then be charged to a CO boiler. Eliminating more than 90% of NO.sub.x emissions is possible by operating the FCC regenerator in partial CO burn mode, then adding air and catalytically converting NO.sub.x precursors at substoichiometric conditions. Conversion of NO.sub.x, if formed in the regenerator, may be achieved as well.

FCC regenerator in partial CO burn with downstream air addition

A method of preparing a modified catalytic molecular sieve for enhanced shape selective hydrocarbon conversions in which a catalytic molecular sieve is modified by being exposed to at least one ex situ selectivation sequence, each sequence including an impregnation of the molecular sieve with a selectivating agent in an aqueous emulsion and a subsequent calcination of the impregnated molecular sieve. The selectivating agent compositions for the ex situ selectivation method are also described, including the selectivating agents, the surfactants, and the aqueous components. Also, a method for moderate steaming of the ex situ selectivated molecular sieve. Also a method for in situ trim-selectivating the ex situ selectivated catalytic molecular sieve. Also described is the modified catalytic molecular sieve modified by this method. Also described is a process for shape selective hydrocarbon conversion comprising contacting a hydrocarbon feedstream under conversion conditions with the modified catalytic molecular sieve.

Method of preparation of ex situ selectivated zeolite catalysts for

There is provided a multizone catalytic process for the treatment of exhaust gas comprising nitrogen oxides, hydrocarbons, and carbon monoxide. In the multizone catalytic process, the exhaust gas is directed through a first zone, a second zone, and a third zone. The first zone comprises a catalyst that is effective for the three-way conversion of nitrogen oxides, hydrocarbons, and carbon monoxide. The second zone comprises materials effective to sorb hydrocarbons, e.g., zeolites ZSM-5 and Beta, particularly iron modified zeolites ZSM-5 and Beta. The second zone is effective for the adsorption of hydrocarbons from the exhaust gas during the cold-start period of operation of an internal combustion engine. The third zone comprises a catalyst that is effective for the oxidation of hydrocarbons and carbon monoxide.

Process for exhaust gas NO.sub.x, CO, and hydrocarbon removal

A molecular sieve catalyst is composited with an inert binder derived from an organic silicon source and organic polymer. The catalyst is used in dewaxing of petroleum chargestocks.

Catalytic dewaxing over silica bound molecular sieve

Raffinate is catalytically hydrodewaxed to lube basestock in a mixture containing between 0.01 and 1 weight percent of pour point depressants comprising the copolymer residue of a mixture of 1-alkene comonomers selected from the group consisting of C.sub.3 -C.sub.28 1-alkenes. The mixture is contacted with hydrogen and shape selective metallosilicate catalyst particles under mild hydrodewaxing conditions to produce an increased yield of lube basestock having a pour point below -25.degree. F. and viscosity index greater than 100.

Catalytic dewaxing of lube basestock raffinates in contact with pour

There is presented a process for the treatment of exhaust gas, which process uses a specially prepared catalyst composition, for the selective catalytic reduction of NO.sub.x contained in the exhaust gas. An embodiment of the process of this invention comprises a catalytic stage to selectively catalytically reduce NO.sub.x over a catalyst composition comprising a molecular sieve that has been treated with a metal in a way effective to maximize metal dispersion. The catalyst of this invention typically comprises a silica, titania, or zirconia binder, e.g. a binder including a high molecular weight, hydroxyl functional silicone resin. The catalyst of this invention may be formed into a desired shape, e.g., by extrusion, and finished in a humidified atmosphere after forming.

Catalytic system for the reducton of nitrogen oxides

There is provided a catalytic method for converting nitrogen oxides to nitrogen (i.e., N.sub.2). The catalyst for this method comprises an acidic solid component comprising a Group IVB metal oxide modified with an oxyanion of a Group VIB metal and further comprising at least one metal selected from the group consisting of Group IB, Group IVA, Group VB, Group VIIB, Group VIII, and mixtures thereof. An example of this catalyst is zirconia, modified with tungstate, and iron. This method may be used for reducing emissions of nitrogen oxides from waste gases, including industrial exhaust gases and automobile exhaust gases. In a particular embodiment, nitrogen oxides in waste gases may be reacted with ammonia before the waste gases are discharged to the atmosphere.

Selective catalytic reduction of nitrogen oxides

A catalytic molecular sieve which has been preselectivated by agglomerating with an organosilicon compound. The invention also includes a method for agglomeration-preselectivation and the shape selective catalyst which results from the agglomeration preselectivation.

Extrusion-modified molecular sieve

There is provided a process for the treatment of exhaust gas, which process uses a specially prepared catalyst composition, for the selective catalytic reduction of NO.sub.x contained in the exhaust gas. An embodiment of the process of this invention comprises a catalytic stage to selectively catalytically reduce NO.sub.x over a catalyst composition comprising an intermediate pore size zeolite catalyst that has been treated with a water soluble iron salt or salt precursor in a way effective to maximize iron dispersion. The intermediate pore size zeolite of this invention preferably has a silica:alumina molar ratio of between about 20 and about 1000. The catalyst of this invention typically comprises a silica, titania, or zirconia binder, preferably a binder including a high molecular weight, hydroxyl functional silicone resin. The catalyst of this invention is preferably formed, e.g., extruded, and then simultaneously calcined and hydrothermally treated.

Method for the reduction of nitrogen oxides using iron impregnated

An exhaust gas treatment process useful for the removal of nitrogen oxides using an iron impregnated zeolite as the catalyst and ammonia as a reducing agent. It is desired to extend the effective temperature range for the selective catalytic reduction (SCR) of nitrogen oxides below about 400.degree. C. This is accomplished in the instant invention through the use of an intermediate pore size zeolite, such as ZSM-5, based catalyst which has been ferrocene treated to substantially incorporate iron into its pores. The catalyst may also be hydrothermally treated at least once, if desired.

Selective catalytic reduction of nitrogen oxides using a ferrocene

A process is described wherein the HCN in FCC hydrocarbon gas streams is converted to NH.sub.3 over a catalyst. This conversion has the desirable result of decreasing the amount of CN.sup.- in the water leaving the sour-water stripper, and ultimately in the refinery water effluent.

Process for the removal of hydrogen cyanide from FCC hydrocarbon product

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Pennington, NJ, United States of America

David S Shihabi