Abstract: A reactor having a shell comprising one or more reactor tubes located within the shell, said reactor tube or tubes comprising a plurality of catalyst receptacles containing catalyst; means for providing a heat transfer fluid to the reactor shell such that the heat transfer fluid contacts the tube or tubes; an inlet for providing reactants to the reactor tubes; and an outlet for recovering products from the reactor tubes; wherein the plurality of catalyst receptacles containing catalyst within a tube comprises catalyst receptacles containing catalyst of at least two configurations.

Abstract: A reactor having a shell comprising one or more reactor tubes located within the shell, said reactor tube or tubes comprising a plurality of catalyst receptacles containing catalyst; means for providing a heat transfer fluid to the reactor shell such that the heat transfer fluid contacts the tube or tubes; an inlet for providing reactants to the reactor tubes; and an outlet for recovering products from the reactor tubes; wherein the plurality of catalyst receptacles containing catalyst within a tube comprises catalyst receptacles containing catalyst of at least two configurations.

Abstract: A reactor having a shell comprising one or more reactor tubes located within the shell, said reactor tube or tubes comprising a plurality of catalyst receptacles containing catalyst; means for providing a heat transfer fluid to the reactor shell such that the heat transfer fluid contacts the tube or tubes; an inlet for providing reactants to the reactor tubes; and an outlet for recovering products from the reactor tubes; wherein the plurality of catalyst receptacles containing catalyst within a tube comprises catalyst receptacles containing catalyst of at least two configurations.

Abstract: A reactor having a shell comprising one or more reactor tubes located within the shell, said reactor tube or tubes comprising a plurality of catalyst receptacles containing catalyst; means for providing a heat transfer fluid to the reactor shell such that the heat transfer fluid contacts the tube or tubes; an inlet for providing reactants to the reactor tubes; and an outlet for recovering products from the reactor tubes; wherein the plurality of catalyst receptacles containing catalyst within a tube comprises catalyst receptacles containing catalyst of at least two configurations.

Abstract: A reactor having a shell comprising: one or more reactor tubes located within the shell, said reactor tube or tubes comprising a plurality of catalyst receptacles containing catalyst; means for providing a heat transfer fluid to the reactor shell such that the heat transfer fluid contacts the tube or tubes; an inlet for providing reactants to the reactor tubes; and an outlet for recovering products from the reactor tubes; wherein the plurality of catalyst receptacles containing catalyst within a tube comprises catalyst receptacles containing catalyst of at least two configurations.

Abstract: A reactor having a shell comprising: one or more reactor tubes located within the shell, said reactor tube or tubes comprising a plurality of catalyst receptacles containing catalyst; means for providing a heat transfer fluid to the reactor shell such that the heat transfer fluid contacts the tube or tubes; an inlet for providing reactants to the reactor tubes; and an outlet for recovering products from the reactor tubes; wherein the plurality of catalyst receptacles containing catalyst within a tube comprises catalyst receptacles containing catalyst of at least two configurations.

Abstract: In a process for carrying out a chemical reaction gaseous reactants are supplied to a first reaction zone including a first catalyst having a first particle equivalent diameter. The first reaction zone is operated such that when the reactants are contacted with the first catalyst a portion of the reactants is converted to the desired product. An intermediate stream of unreacted reactants and the desired product is removed and passed to a second reaction zone including a tubular reactor. Tubes of the reactor are catalyst carriers containing a second catalyst having a second particle equivalent diameter smaller than the first particle equivalent diameter. The second reaction zone is operated such that when the unreacted reactants are contacted with the second catalyst, at least some of the unreacted reactants are converted to the desired product. A product stream is then recovered. Apparatus for carrying out the process is also described.

Abstract: In a process for carrying out a chemical reaction gaseous reactants are supplied to a first reaction zone including a first catalyst having a first particle equivalent diameter. The first reaction zone is operated such that when the reactants are contacted with the first catalyst a portion of the reactants is converted to the desired product. An intermediate stream of unreacted reactants and the desired product is removed and passed to a second reaction zone including a tubular reactor. Tubes of the reactor are catalyst carriers containing a second catalyst having a second particle equivalent diameter smaller than the first particle equivalent diameter. The second reaction zone is operated such that when the unreacted reactants are contacted with the second catalyst, at least some of the unreacted reactants are converted to the desired product. A product stream is then recovered. Apparatus for carrying out the process is also described.

Abstract: In a process for recovering water, metals, soluble organics and insoluble organics from a process for the production of a polycarboxylic acid, the stream is cooled to a temperature at which dissolved organics precipitate. The precipitate organics are separated from a liquid stream and recycled to the production process. The liquid stream is then treated with an alkali to convert remaining organics to the alkali salt form and the metals present to be converted to an insoluble form. The insoluble metals are recovered from a liquid stream and this liquid stream, with the alkali salts of the organics, is passed to a membrane separation unit where it is separated into a permeate comprising water and a retentate comprising water and alkali organic salts. The permeate is recovered and recycled to the production process. The retentate also is recovered.

Abstract: In a reactor tube in which a plurality of catalyst carriers are disposed, each catalyst carrier is an annular container having a perforated inner wall defining a tube, a perforated outer wall, a top surface closing the annular container and a bottom surface closing the annular container. A surface closes the bottom of the tube and a skirt extends upwardly from the perforated outer wall of the annular container from a position at or near the bottom surface of the container. A seal is located at or near the top surface and extends outward from the container beyond an outer edge of the skirt. The reactor tube additionally includes a temperature measuring device configured to measure the temperature in two or more catalyst carriers within the reactor tube.

Abstract: In a process for recovering water, metals, soluble organics and insoluble organics from a process for the production of a polycarboxylic acid, the stream is cooled to a temperature at which dissolved organics precipitate. The precipitate organics are separated from a liquid stream and recycled to the production process. The liquid stream is then treated with an alkali to convert remaining organics to the alkali salt form and the metals present to be converted to an insoluble form. The insoluble metals are recovered from a liquid stream and this liquid stream, with the alkali salts of the organics, is passed to a membrane separation unit where it is separated into a permeate comprising water and a retentate comprising water and alkali organic salts. The permeate is recovered and recycled to the production process. The retentate also is recovered.

Abstract: In a reaction vessel for the purification of crude aromatic carboxylic acid, a bed of hydrogenation catalyst having a vapor space is located above the hydrogenation catalyst bed. A packed bed and a holdup section are located within the vapor space and spaced above the catalyst bed. The reaction vessel has means for introducing crude aromatic carboxylic acid and means for introducing hydrogen to the reaction vessel at respective locations such that in use the crude carboxylic acid contacts the hydrogen in the packed bed. The reaction vessel also has means for removing purified aromatic carboxylic acid.

Abstract: In a process for the separation of solid carboxylic acid fines from mother liquor that includes such fines, the mother liquor is fed to a settlement drum at above atmospheric pressure. The mother liquor having a lower concentration of carboxylic fines than that fed to the settlement drum is then removed, wherein the mother liquor removal occurs at a point above the point at which the mother liquor containing fines is fed to the settlement drum. In a system for performing the separation process, a settlement drum has an inlet for mother liquor with carboxylic acid fines and an outlet for mother liquor having a lower concentration of carboxylic acid fines content than that of the mother liquor introduced via the inlet. The settlement drum is configured to operate at above atmospheric pressure and the outlet is located at a point in the settlement drum above the inlet.

Abstract: In a process for the separation and drying of crude carboxylic acid crystals from a slurry in a solvent, the slurry is supplied to a filter operating at pressure and at a temperature above the atmospheric boiling point of the solvent. A cake of separated crystals is removed from the filter and passed to a thermal dryer. In a system for the separation and drying of crude carboxylic acid from a slurry in a solvent, a pressure filter device has a slurry inlet and an outlet for a cake of carboxylic acid crystals. The system also has a thermal dryer and means for transporting the cake of carboxylic acid crystals from the pressure filter device to the dryer. The pressure filter device is configured to operate at a pressure and temperature above the atmospheric boiling point of the solvent.

Abstract: In a process/system for the purification of aromatic dicarboxylic acid (ACA), crude ACA solids are slurried with water recycled from at least a filtration step in a feed preparation zone. Flash steam in vapour phase is supplied to the zone from at least one of a crystallisation step, a filtration step, and a drier step. The slurried ACA solids are preheated to form a solution that is then hydrogenated. The ACA is allowed to crystallise and then crystals of pure ACA are filtered out and water is recovered in a single stage filtration process. Recovered water is supplied to the feed preparation zone and the crystals are dried and recovered. The flash steam recovered from the crystallisation step, filtration step and/or drier step is recovered as a vapour phase stream having a pressure from about atmospheric to 5 barg and supplied to the feed preparation zone without phase change.

Abstract: In a process for the separation and drying of crude carboxylic acid crystals from a slurry in a solvent, the slurry is supplied to a filter operating at pressure and at a temperature above the atmospheric boiling point of the solvent. A cake of separated crystals is removed from the filter and passed to a thermal dryer. In a system for the separation and drying of crude carboxylic acid from a slurry in a solvent, a pressure filter device has a slurry inlet and an outlet for a cake of carboxylic acid crystals. The system also has a thermal dryer and means for transporting the cake of carboxylic acid crystals from the pressure filter device to the dryer. The pressure filter device is configured to operate at a pressure and temperature above the atmospheric boiling point of the solvent.

Abstract: In a process for the separation of solid carboxylic acid fines from mother liquor that includes such fines, the mother liquor is fed to a settlement drum at above atmospheric pressure. The mother liquor having a lower concentration of carboxylic fines than that fed to the settlement drum is then removed, wherein the mother liquor removal occurs at a point above the point at which the mother liquor containing fines is fed to the settlement drum. In a system for performing the separation process, a settlement drum has an inlet for mother liquor with carboxylic acid fines and an outlet for mother liquor having a lower concentration of carboxylic acid fines content than that of the mother liquor introduced via the inlet. The settlement drum is configured to operate at above atmospheric pressure and the outlet is located at a point in the settlement drum above the inlet.

Abstract: In a process for the separation of carboxylic acid from a slurry in a solvent, a slurry with crystals of carboxylic acid is supplied to a filter operating at pressure and at a temperature above the atmospheric boiling point of the solvent. Inert gas is mixed with the solvent and the mixture is supplied to the filter. A cake of separated crystals is removed from the filter. Inert gas removed from the filter is not recycled. In a system for performing such separation, a pressure filter device has a slurry inlet, and an outlet. Means for mixing inert gas and solvent, and means for supplying the mixture to the pressure filter are provided. The pressure filter device is configured to operate at pressure and at a temperature above the atmospheric boiling point of the solvent. The system does not include means for recycling inert gas removed from the filter.