Abstract: A deactivated reforming catalyst comprising a type L zeolite containing a Group VIII noble metal may be regenerated and have enhanced dispersion by a method involving contacting the catalyst with oxygen and water at elevated temperatures, contacting the catalyst at elevated temperatures with a source of chlorine such as HCl or Cl.sub.2, and preferably oxygen and water, contacting the catalyst at elevated temperatures with oxygen and optionally water, and contacting the catalyst at elevated temperatures with hydrogen and optionally water to reduce the catalyst.Preferably the noble metal is platinum.

Abstract: Included is a process for redispersing catalysts wherein the catalyst metal is selected from the group consisting of ruthenium, osmium, rhodium and palladium comprising contacting the catalyst serially with (1) a reducing agent; (2) a halogen redispersing agent; and (3) a reducing agent, under conditions sufficient to redisperse the sintered catalyst. A preliminary oxygen treatment is optional. Also included are the novel catalysts such as redispersed by the foregoing process and processes in which sintered catalysts are redispersed and in which the redispersed catalysts are employed.The redispersed catalysts can have very high activity and can even have activity higher than originally found. A preferred metal is palladium and a preferred support is alumina.A preferred process for employing the redispersed catalyst is the production of .alpha.-substituted acrylate esters.

Abstract: The present invention relates to a process for the regeneration and stabilization of certain phosphorus-vanadium-oxygen complex catalysts or phosphorus-vanadium-oxygen co-metal complex catalysts, with halogen-containing components and subsequently treating the catalyst with phosphorus compounds. These catalysts are useful for the manufacture of maleic anhydride from butane feedstock.

Abstract: A method for regenerating coke-contaminated catalyst particles achieves better utilization of oxygen and minimizes surface area loss of the catalyst by confining particles in the combustion section of a regeneration zone to a tapered bed configuration. In this method, catalyst particles move through the regeneration zone in continuous or semi-continuous flow and are formed into a vertically elongated bed of particles in the regeneration zone. An oxygen-containing gas is passed through the particle bed in a transverse direction and initiates combustion of the coke deposits along a burn front that extends diagonally through the catalyst bed from the inlet surface of the bed to the outlet surface of the bed.

Abstract: The present invention is a process for regenerating a sulfur-contaminated, highly selective, large-pore zeolite catalyst. It comprises a multistep process involving exposure of the catalyst to a combination of oxidizing conditions, reducing conditions and treatment with a halogen acid gas. These conditions are effective to agglomerate a Group VIII metal and remove sulfur. Thereafter, the catalyst is oxychlorinated to redisperse the Group VIII metal over the catalyst surface. A carbon removal step is optionally included.

Abstract: A process for dispersing or redispersing relatively large crystallites of an agglomerated Group VIII noble metal species present on a porous inorganic support is disclosed. The process includes contacting the agglomerated noble metal species, e.g., palladium or platinum, present on the support, e.g., alumina, silica or a zeolite such as ZSM-5 from which at least a major portion of any extraneous matter such as coke or other residue has previously been removed, with nitric oxide (NO) alone or in admixture with a source of halogen such as Cl.sub.2 and thereafter removing sorbed nitrogen oxide(s). The thus treated metal-loaded catalyst demonstrates substantially increased benzene hydrogenation activity (BHA) compared to the same catalyst prior to treatment indicating significant dispersion/redispersion of the metal crystallities as smaller crystallities.

Abstract: Improvements in a reforming process for the regeneration and reactivation of a bed of a reforming catalyst, notably an iridium-containing catalyst, coked and catalytically deactivated during the on-oil portion of a reforming cycle. The reactor containing the catalyst is contained in a multi-reactor unit, the individual reactors of which are connected in series via suitable piping and valving. The reactor can be alternately manifolded with production facilities during the on-oil portion of the operating cycle during which period the catalyst of said reactor becomes coked, and can be manifolded alone or with other reactors with a ferrous metal regeneration circuit during the catalyst regeneration and reactivation portion of an operating cycle during which period the catalyst is regenerated and reactivated.

Abstract: An improved catalyst demetallization process involves chlorinating the metal contaminated catalyst at elevated temperatures and contacting the chlorinated catalyst with a liquid aqueous composition to produce a demetallized catalyst. Improved catalytic activity is obtained utilizing a catalyst comprising at least one crystalline material capable of promoting the hydrocarbon conversion, and cooling the chlorinated catalyst prior to contact with the liquid aqueous composition. An improved hydrocarbon conversion process is also disclosed.

Abstract: A process is described for rejuvenation of a deactivated highly siliceous noble metal-containing zeolite catalyst having a framework silica to alumina ratio of at least about 20 which contains agglomerated noble metal in its deactivated state. The process comprises redispersing the noble metals associated with the deactivated catalyst by contacting the catalyst with a stream of inert gas containing molecular chlorine, water and optionally, oxygen, a temperatures ranging from about 150.degree. to about 450.degree. C., a partial pressure of chlorine of from about 6 to about 15 Torr and a ratio of partial pressure of water to partial pressure of chlorine of from about 0.01 to about 2 for a period of time sufficient to achieve redispersion; purging said catalyst with an inert gas; and reducing said purged catalyst in a stream of hydrogen at a temperature ranging from about 140.degree. C. to 550.degree. C.

Abstract: The present invention relates to a process for the activation of siliceous catalysts selected among zeolites with a high silica content, organosilicates, polymorphous crystalline silicas and zeolites deactivated by treatment with water vapor.According to the invention, the catalyst is activated by reacting aluminum chloride and hydrogen chloride, both in gaseous phase with the catalyst, at a temperature between about 150.degree. and 600.degree. C. in the same reactor, the possible excess of gaseous hydrogen chloride being removed by means of an inert gas, such as nitrogen.

Abstract: A process is described for rejuvenation of a deactivated highly siliceous noble metal-containing zeolite catalyst which contains agglomerated noble metals. The process comprises initially reducing the deactivated catalyst in hydrogen, pretreating the thus reduced catalyst with an inert gas stream containing about 0.001 to 10 weight percent hydrogen chloride, redispersing the noble metal with an inert gas stream containing about 0.001 to 10 weight percent Cl in the form of Cl.sub.2 or Cl-containing organic material, and subsequently reducing the catalyst. The Cl-treatments may optionally occur in the presence of oxygen or sources of oxygen.

Abstract: A process is provided for converting oxygenates to hydrocarbons over catalyst prepared by a method for reactivating a catalyst composition comprising a crystalline zeolite material having a silicon/aluminum atomic ratio of at least about 2, said catalyst composition having been deactivated by contact with steam. The catalyst preparation method involves contacting said steam-deactivated catalyst composition with an aluminum compound at elevated temperature, and contacting said aluminum compound contacted catalyst composition with an aqueous acid solution.

Abstract: Reaction mixtures which are obtained on hydroformylation or carbonylation of olefinically unsaturated compounds and which contain dissolved non-volatile complex compounds of metals of group VIII of the periodic table are worked up by a method wherein the products, after distillative removal of low-boiling constituents alone, or of these constituents plus a part of the high-boiling residue, or a part of the high-boiling residue after distillative removal of the desired products, are or is extracted with carbon dioxide, a C.sub.2 -C.sub.4 -paraffin, a C.sub.2 -C.sub.4 -olefin or a normally gaseous halohydrocarbon at above the critical temperature and above the critical pressure of these (extractant) compounds.

Abstract: In a process for treatment of a fresh iridium-containing catalyst, the improvement consists of a three step procedure in sequence including treatment with oxygen, treatment with hydrogen chloride, and treatment with a reducing agent such as hydrogen.

Abstract: The useful life of vanadium-phosphorus-oxygen (PVO) catalyst in fixed bed reactors can be substantially extended by treatment with a phosphorus compound followed by steam treatment. The PVO catalysts may be treated with steam after long periods (months) of only phosphorus compound treatment and the benefit of the present invention obtained or the phosphorus and steam treatments may be of only a few hours duration and sequential. In extending the useful life of the PVO catalyst according to the present invention, the temperature profile in the catalyst bed is restored to substantially the same profile as the fresh catalyst.

Abstract: A process is disclosed for reactivating a coked and agglomerated iridium and selenium containing catalyst and particularly platinum-iridium-selenium on alumina reforming catalysts. The process includes a low temperature decoking step to achieve partial decoking while minimizing agglomeration, a reducing step involving contacting the decoked agglomerated catalyst with a reducing gas such as hydrogen to reduce agglomerated iridium oxides to the free metal, a halide pretreatment step to increase the chloride level of the catalyst to about 1.3 weight percent and above, and a halogen redispersion step. The redispersion step is performed with a mixture of elemental halogen and water vapor.

Abstract: A process is described for reactivating agglomerated iridium-containing catalysts such as Pt-Ir on Al.sub.2 O.sub.3 reforming catalyst. The agglomerated catalyst is decoked to remove carbon deposits; treated with hydrogen to reduce metal oxides to the free metals; pretreated with hydrogen halide to provide at least about a 1.3 weight percent halide content; and treated with a low mass flow rate of chlorine of about one gram chlorine per 100 grams catalyst per hour. Use of a low mass halogen flow rate significantly retards ferrous metal corrosion and significantly reduces the quantity of chlorine normally used in achieving high redispersion values.

Abstract: A process is disclosed for reactivating an agglomerated iridium-containing catalyst and particularly platinum-iridium on alumina reforming catalysts. The process includes a reducing step involving contacting a decoked agglomerated catalyst with a reducing gas such as hydrogen to reduce agglomerated iridium oxides to the free metal, a hydrogen halide pretreatment step to provide a halide level to the catalyst of about 1.3 weight percent, and an elemental halogen redispersion step. The hydrogen halide pretreatment step is performed under elemental oxygen-free conditions prior to redispersion and allows high iridium redispersion values to be obtained. If no iridium oxides are initially present, the hydrogen step is optional.

Abstract: Molecular sieve catalysts, such as alumino-silicate zeolites, used in hydrocarbon conversion and separation processes, are restored after their recommended use-cycle service, by novel methods of regeneration and metal redispersion, or rejuvenation.An additive compound is injected into the catalyst during regeneration, or coke removal. The additive is of a molecular diameter large enough to prevent the additive from being captured by a cell of the catalyst, and is preferably of a pH which promotes adsorption of the additive onto the zeolite material.Metal-coated zeolite catalysts are rejuvenated, preferably after regeneration, by injecting a halogen compound followed by the above additive compound, and then heating the catalyst to a high temperature. This procedure is effective in re-dispersing metal agglomerates uniformly throughout the catalyst to restore the original metal coating.

Abstract: Catalysts containing niobium or tantalum halides which have been deactivated by contact with oxygen are regenerated by being contacted with a halogenated hydrocarbon.

Abstract: A process is described for the redispersion of iridium-containing catalysts involving a low temperature hydrogen reduction step, i.e., from 190.degree. C. up to about 250.degree. C. after a coke burn-off. The low temperature reduction step allows milder conditions during subsequent halogen redispersion.

Abstract: A process is provided for reactivating a catalyst composition comprising a crystalline zeolite material having a silicon/aluminum atomic ratio of at least about 2, said catalyst composition having been deactivated by contact with steam. The method involves contacting said steam-deactivated catalyst composition with an aluminum compound at elevated temperature, and contacting said aluminum compound contacted catalyst composition with an aqueous acid solution.

Abstract: A process is disclosed for re-activating a used solid acid catalyst wherein the catalyst is calcined to burn off heavy hydrocarbons and subsequently halogenated with chlorine and/or fluorine or their compounds entrained by an inert gas or a non-reducing gas. The resulting re-activated catalyst finds wide application in isomerization and oligomerization of olefins, conversion of methanol into hydrocarbons, and isomerization, disproportionation or trans-alkylation of aromatic hydrocarbons.

Abstract: A process is disclosed for reactivating an agglomerated iridium-containing catalyst and particularly platinum-iridium on alumina reforming catalysts. The process includes a reducing step involving contacting a decoked agglomerated catalyst with a reducing gas such as hydrogen to reduce agglomerated iridium oxides to the free metal, a hydrogen halide pretreatment step to provide a halide level to the catalyst of about 1.3 weight percent, and an elemental halogen redispersion step. The hydrogen halide pretreatment step is performed under elemental oxygen-free conditions prior to redispersion and allows high iridium redispersion values to be obtained. If no iridium oxides are initially present, the hydrogen step is optional.

Abstract: A process is disclosed for reactivating an agglomerated iridium-containing catalyst and particularly a platinum-iridium on alumina reforming catalyst. The process includes contacting an agglomerated catalyst with a reducing gas such as hydrogen to reduce agglomerated iridium oxides to the free metal, a hydrogen chloride pretreatment step to increase the chloride level of the catalyst to about 1.6 weight percent and above, and a redispersion step involving contacting with elemental oxygen. The process eliminates the need for gaseous chlorine in the redispersion feedstream. If no iridium oxides are initially present, the hydrogen reduction step is optional.

Abstract: A process is disclosed for reactivating an agglomerated iridium-containing catalyst and particularly platinum-iridium on alumina reforming catalysts. The process includes contacting a substantially decoked agglomerated catalyst with a reducing gas such as hydrogen to reduce agglomerated iridium oxides present to the free metal, a hydrogen halide pretreatment step to increase the halogen level of the catalyst to about 1.3 weight percent and above, and a redispersion step involving hydrogen halide and elemental oxygen. Use of hydrogen halide and elemental oxygen in the redispersion treatment eliminates the need for use of elemental chlorine gas. If no iridium oxides are initially present, the hydrogen reduction step is optional.

Abstract: A process is described for reactivating agglomerated iridium-containing catalysts such as Pt-Ir on Al.sub.2 O.sub.3 reforming catalyst. The agglomerated catalyst is decoked to remove carbon deposits; treated with hydrogen to reduce metal oxides to the free metals; pretreated with hydrogen halide to provide at least about a 1.3 weight percent halide content; and treated with a low mass flow rate of chlorine of about one gram chlorine per 100 grams catalyst per hour. Use of a low mass halogen flow rate significantly retards ferrous metal corrosion and significantly reduces the quantity of chlorine normally used in achieving high redispersion values.

Abstract: A method of hydrocracking using a zinc catalyst in the hydrogenation step comprising providing a hydrocarbonaceous feed of coal or tar to a hydrogenation means,removing spent zinc and catalyst from said hydrogenation means to a regeneration means,heating said spent zinc catalyst in said regeneration means,providing hydrogen chloride to said regeneration means,said spent zinc catalyst comprising ZnS, whereby ZnCl.sub.2 gas is formed,contacting at least a portion of said ZnCl.sub.2 with steam to form ZnO,conveying said ZnO and ZnCL.sub.2 to said hydrogenation means.

Abstract: A process for reactivating a vanadium-containing oxidation catalyst, wherein the catalyst is treated first at from 100.degree. to 600.degree. C., with a volatile phosphorus compound in the presence of an oxygen-containing gas, and then at from 50.degree. to 600.degree. C. with sulfur trioxide or a mixture of a volatile sulfur compound and an oxygen-containing gas.