Abstract:
A process for regenerating a spent particulate wax-containing cobalt-based Fischer-Tropsch synthesis catalyst is provided. The process includes subjecting the spent wax-containing catalyst sequentially to a dewaxing treatment, an oxidation treatment and a reduction treatment. During the dewaxing treatment, the spent wax-containing catalyst is at least partially dewaxed, with dewaxed catalyst particles being produced. During the oxidation treatment, an oxygen-containing gas is passed through a bed of the dewaxed catalyst particles at an operating temperature T°C where 150
Abstract:
Used noble metal-containing titanium or vanadium zeolite catalysts, that have been employed in the epoxidation of olefins with hydrogen and oxygen, are regenerated by contacting the spent catalyst with water or an alcohol/water mixture at a temperature of 25°C to 200°C.
Abstract:
A method for recovering and reusing a ring-halogenation catalyst comprises: (A) contacting an aromatic compound with chlorine or bromine in the presence of a catalyst composition, where the catalyst composition comprises at least one salt comprising a Group 4 - 13 metal, a lanthanide metal, or an actinide metal; and at least one organic counterion derived from an organic acid having a pKa relative to water of 0 or greater; and at least one organic sulfur compound; to form a first product mixture comprising a monochloro or a monobromo aromatic compound and a Group 4 - 13 metal halide, a lanthanide metal halide or an actinide metal halide; (B) separating the metal halide from the first product mixture; and (C) contacting at least a portion of the metal halide and an aromatic compound with chlorine or bromine, and at least one organic sulfur compound; to form a second product mixture comprising a monochloro or a monobromo aromatic compound and a Group 4 - 13 metal halide, a lanthanide metal halide or an actinide metal halide.ving a pKa relative to water of 0 or greater; and at least one organic sulfur compound.
Abstract:
A method of regenerating an acidic catalyst is described. A silane compound is contacted with an acidic catalyst that contains conjunct polymer, which releases the conjunct polymer from the acidic catalyst. The acidic catalyst can then be re-activated with acid. The conjunct polymer can be separated from the silane compound, and the silane compound can be recycled.
Abstract:
A process for the preparation of a catalyst useful for conducting carbon monoxide hydrogenation reactions, especially Fischer-Tropsch reactions. The steps of the process begin with the activation, or reactivation, of a deactivated catalyst, or with the preparation and activation of a fresh catalyst. In accordance with the latter, the steps of the process comprise, first contacting, in one or more steps, a powder or preformed, particulate refractory inorganic support with a liquid, or solution in which there is dispersed or dissolved a compound, or salt of a catalytically active metal, or metals, to impregnate and deposit the metal, or metals, upon the support, or powder. The metal, or metals, impregnated support is calcined following each impregnation step to form oxides of the deposited metal, or metals. The calcined catalyst precursor is then treated with a solution of a chelating compound, preferably a poly-or multidentate chelating compound, sufficient to complex with, extract and remove a portion of the oxides of the metal, or metals. The catalyst is activated by reduction; suitably by contact with hydrogen. In the activation, or reactivation of a deactivated catalyst, the catalyst is first treated with the chelating compound to extract a portion of the oxides of the metal, or metals, and the catalyst is then reduced. In either event, the activated or reactivated catalyst has high activity, or high C5+ selectivity, or both high activity and C5+ selectivity in conducting carbon monoxide hydrogenation reactions. The productivity of the process is increased.
Abstract:
A process for the regeneration of a catalyst is presented. The catalyst is in a reactor for use in benzene alkylation, and periodically needs to be regenerated. The reactor is taken off-line, and a regenerant is passed through the reactor, producing an effluent stream. A portion of the effluent stream is recycled through the reactor without passing through a clean-up process.
Abstract:
Systems, methods and apparatuses for regenerating a Fischer-Tropsch ("FT") catalyst that is to be regenerated with a first wash fluid comprising at least one hydrocarbon and contacting the washed FT catalyst with a gas comprising hydrogen, method of regenerating a Fischer-Tropsch ("'FT") catalyst that is at least partially spent through having been utilized to produce FT hydrocarbons via FT synthesis in an FT reactor. The method includes the steps of washing the FT catalyst to be regenerated with a first wash fluid. The FT catalyst to be regenerated comprises pores, and at least a fraction of the pores contain a first mixture of hydrocarbons, The first wash fluid comprises at least one hydrocarbon, and the average molecular weight of the at least one hydrocarbon of the first wash fluid is less than the average molecular weight of the hydrocarbons in the first mixture of hydrocarbons.
Abstract:
A method for regenerating a titanosilicate catalyst, comprising a step of mixing a titanosilicate having reduced catalytic ability with a cyclic secondary amine, and a method for producing an oxirane compound, which comprises a step of reacting hydrogen peroxide with a C2-C12 compound having a carbon-carbon double bond, in the presence of a titanosilicate catalyst obtained by the regeneration method.
Abstract:
A unified process which couples a unique in-situ catalyst regeneration process with a continuous reactive distillation under pressure for the alkylation of light aromatic hydrocarbons such as benzene with C 2 -C 30 olefins using a solid acid alkylation catalyst supported in the reflux zone (21) of a distillation column (section A). Periodic regeneration of the catalyst (sections E, F and G) is carried out with a countercurrent injection of a C 4 -C 16 paraffin (35) below the benzene rectification zone at the top of the column, but above the catalyst zone while the aromatic hydrocarbon reaction feedstock (17) is injected continuously at a point above a rectification zone at the base of the column where the aromatic compound is separated from the paraffin and by-products washed from the catalyst. The use of the C 4 -C 16 paraffin with the aromatic at a mole fraction in the range of 40 to 90% enables a regeneration temperature of about 175 - 250°C. to be achieved and maintained by adjusting the column pressure and aromatic reflux rate. Significantly lower pressures, on the order of 125 to 370 psig, are required to achieve regeneration temperature than would be otherwise required with the use only of the aromatic hydrocarbon to dilute and wash the by-products from the catalyst surfaces.