Abstract: Vinyl aromatic-conjugated diene copolymers having polymer chains which end with an alkali metal and which are obtained by the polymerization in solution of at least one vinyl aromatic hydrocarbon and of a conjugated diene in the presence of a catalyst based on an alkali metal are decolorized by treating the copolymer with a monocarboxylic acid of general formula(Y).sub.2-n --X--(R--COOH).sub.nin which X is S, S--CH.sub.2 --S, or S--S, and Y and R are alkyl radicals having 1 to 16 carbon atoms and n is 1 or 2.

Abstract: The present invention relates to a process for removing arsine from a light olefin to containing hydrocarbon feedstock, said process comprising the steps of (a) passing said feedstock over an absorbent material comprising nickel deposited on a support material wherein nickel is present as both nickel oxide and metallic nickel; and (b) recovering a stream having a substantially reduced arsine content.

Abstract: A process is disclosed for eliminating waxy paraffins from hydrocarbon feedstocks having an initial boiling temperature above about 180.degree. C. and containing sulphur, by selective cracking of the straight chain paraffinic hydrocarbons, said process comprising passing said feedstock over a crystalline silica polymorph of the silicalite type under suitable operating conditions for cracking the straight chain paraffins.

Abstract: A process for the treatment of a gas oil fraction to produce a lighter fraction useful as diesel fuel and/or gasoline comprising subjecting the gas oil fraction to dewaxing and mild hydracracking treatments. The dewaxing is carried out over a silicalite dewaxing catalyst. The dewaxing and mild hydrocracking treatments may be carried out sequentially or simultaneously. The gas oil feed may be passed successively through a silicalit-catalyst bed, a bed of hydrotreating catalyst and a bed of hydrocracking catalyst.

Abstract: A novel crystalline silica composition having a silica to alumina atomic ratio not lower than 80 and having a certain specific X-ray diffraction pattern after calcination in air for at least 3 hours at a temperature of at least 500.degree. C.

Abstract: A process for the alkylation of aromatic compounds employing silicalite of extremely low sodium content. A feedstock containing an aromatic substrate such as benzene is supplied along with an alkylating agent such as ethylene to a reaction zone containing a silicalite alkylation catalyst having a sodium content of less than 100 ppm Na.sub.2 O. Steam may be cofed to the reaction zone in an amount of at least 1 wt. % based upon the aromatic substrate. The low sodium silicalite has a substantially better aging quality in the alkylation process than does silicalite which normally has a higher sodium content.

Abstract: Disclosed is a process for preparing crystalline silicas having the monoclinic symmetry which comprises the step of calcining in air for at least 3 hours at a temperature of at least 500.degree. C. a crystalline silica of the silicalite type having a silica to alumina atomic ratio of at least 80.

Abstract: A process for pretreating a Ziegler-type catalyst for use in olefin polymerization reactions. An olefin monomer is aded to a fluid carrier stream containing a Ziegler-type catalyst. The carrier stream containing the monomer and the catalyst is passed through an elongated tubular reactor at a flow rate sufficient to provide a residence time in the tubular reactor of less than 1 minute and under temperature conditions to prepolymerize the catalyst within the tubular reactor without plugging of the reactor. In a specific embodiment the residence time within the reactor is no more than 10 seconds, and more particularly, no more than 2 seconds.

Abstract: A process for the disproportionation of a toluene feedstock containing ethylbenzene over an aluminum deficient mordenite catalyst. The mordenite catalyst has a silica/alumina mole ratio of at least 30. The feedstock contains at least 5 wt. % ethylbenzene. Hydrogen is supplied to the disproportionation reactor zone along with the toluene feedstock.

Abstract: A catalytic treatment process is disclosed, which is carried out under pressure, in the presence of water, and with a molecular sieve catalyst which is TEA-silicate or silicalite previously stabilized by halogenation. This process may be applied to the aromatization or to the isomerization of hydrocarbon feedstocks, and to the oligomerization of olefins. The conversion rate of the process is very stable as a function of time.

Abstract: Process for the isomerization of xylene feedstock employing an aluminum-deficient mordenite catalyst. The xylene feedstock is passed into a reaction zone and in contact with a mordenite catalyst having a silica/alumina mole ratio of at least 30. The xylene feedstock may comprise a substantially pure meta-xylene, a mixture of xylene isomers, or in the preferred embodiment, a mixture of xylene isomers and ethylbenzene in which para-xylene is present in less than an equilibrium amount, and ethylbenzene present in an amount greater than the para-xylene content. The reaction zone is operated at a temperature within the range of 350.degree.-600.degree. C. and a hydrogen pressure within the range of 200-1000 psig to effect isomerization of xylene isomers to provide an increased para-xylene content and disproportionation of ethylbenzene to provide a reduced ethylbenzene content in the product.

Abstract: A process for the disproportionation of a toluene containing feedstock over an aluminum deficient mordenite catalyst having a silica/alumina mole ratio of at least 30. The feedstock and hydrogen co-feed are supplied to a reaction zone containing the mordenite catalyst and which is operated under a temperature and pressure condition to effect the disproportionation of toluene to benzene and xylene. The supply of toluene feedstock to the reaction zone is interrupted while continuing the supply of hydrogen to the reaction zone. By continuing the supply of hydrogen to the reaction zone during periods of interruption of the toluene feedstock, the aging quality of the aluminum-deficient mordenite catalyst is improved.

Abstract: Process for the isomerization of a xylene feedstock employing a silicalite catalyst. A xylene feedstock containing a mixture of xylene isomers and ethylbenzene is passed to a reaction zone containing the silicalite catalyst. Para-xylene is present in the feedstock in less than an equilibrium amount, and ethylbenzene is present in a concentration greater than the para-xylene concentration. Hydrogen and/or water are also supplied to the reaction zone. The reaction zone is operated under conditions to effect isomerization of xylene isomers to provide an increased para-xylene content, and disproportionation of ethylbenzene to provide a decreased ethylbenzene content.

Abstract: Process for the disproportionation of toluene employing an aluminum deficient mordenite catalyst. A toluene containing feedstock is supplied to a reaction zone containing a mordenite catalyst having a silica/alumina mole ratio of at least 30. The toluene WHSV is more than one. A hydrogen cofeed is supplied at a hydrogen/toluene mole ratio of 3-6, and the reaction zone is operated at a temperature within the range of 370.degree.-500.degree. C. and a hydrogen pressure of at least 500 psig. The toluene feedstock can have a moisture content in excess of 25 ppm and typically will have a water content ranging from about 50 ppm up to about the saturation point, about 250 ppm. A start-up procedure employs passing a hot preflush gas over the catalyst to dehydrate water from the catalyst prior to passing the toluene feedstock to the catalyst.

Abstract: A process for the selective alkylation of monoalkylbenzene into dialkylbenzenes wherein the para isomer of the disubstituted product is present in a concentration greater than in a thermodynamic equilibrium is provided.The method comprises passing the monoalkylbenzene and an alkylating agent capable of methylation, ethylation or propylation through a reaction zone containing an unmodified crystalline silica catalyst of the silicalite type having the monoclinic symmetry.

Abstract: A process for producing aromatic compounds from a paraffin containing feedstock in which the feedstock is passed to a reaction zone into contact with a multi-component catalyst system. The catalyst system comprises a discreet physical mixture of a silicalite homologation catalyst and a metal or metal oxide dehydrogenation catalyst. The process is carried out to cause the dehydrogenation of paraffins to olefins, the oligomerization of olefins to cyclic napthenes and the aromatization of the napthenes. Reaction conditions and relative catalyst concentrations to provide a relationship between the thermodynamic constraint for the dehydrogenation of the paraffins and the balancing of the kinetics of the dehydrogenation and oligomerization reactions to limit the olefin concentration to a value which does not result in substantial coking of the catalyst system.

Abstract: Downhole well tools and anchoring means therefore including a chemical cutting tool having improved slip actuating and slip array assemblies. The cutting tool includes a slip shaft provided with fluid passageway and having a slip array slidably disposed thereon. The tool further includes slip expansion means secured to the shaft adjacent to the slip array. A piston sleeve is slidably disposed on the shaft and connected to the slip array and defines a piston chamber in fluid communication with the shaft passageway such that the application of fluid pressure drives the piston sleeve and slip array to a deployed position in which the slip array is expanded. Biasing means located externally of the piston sleeve function to bias the piston sleeve to a retracted position upon release of fluid pressure. The slip array is comprised of spaced slip segments which are biased inwardly by means of cantilever springs secured to a structural member of the logging tool.

Abstract: A cylindrical downhole chemical jet cutting tool including a generally cylindrical slip body having pipe gripping slips connected to a co-axially disposed expandable piston-cylinder biased toward a retracted position by a return spring; each slip includes a pivoting head pivotally retained by the slip body and biased toward a retracted from deployed position by a garter spring. Each slip defines at least two sets of gripping teeth having different gripping faces such that each gripping face becomes substantially parallel with the tool body axis as the slip becomes deployed a different respective distance from the tool. A slip expansion mandrel disposed within the slip array deploys the slips into gripping engagement as the piston-cylinder is actuated in response to application of fluid pressure. A chemical fluid cutting means including a fluid chamber defined within the tool body between two diaphragms can rupture from application of a designated differential fluid pressure.

Abstract: An ion exchange process for the recovery of uranium from a pregnant lixiviant employed in uranium leaching operations in which the lixiviant contains chloride ions inhibiting the adsorption of uranyl ions. The ion exchange resin employed to adsorb uranium from the lixiviant has cationic adsorption sites provided by quaternary ammonium groups having a hydroxyalkyl group as a quaternizing substituent. Through the use of a resin of this type, the resin loading in the presence of chloride ions is materially increased.

Abstract: A radioactivity well logging tool employs an epithermal neutron detector having a thermal neutron counter surrounded by a thermal neutron shield. Located between the counter and the shield is a neutron moderating material for slowing down epithermal neutrons penetrating the thermal neutron shield to enable their counting by the thermal neutron counter.