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AssigneeDavy Process Technology Limited
InventorsGeorge E. Harrison, John Scarlett, Michael A. Wood, Donald H. McKinley
Estimating the term…
Esterification is carried out in a column reactor (14) in which there is a plurality of esterification trays (15) each having predetermined liquid hold-up and containing a charge of a solid esterification catalyst thereon. e.g. an ion exchange resin containing a --SO.sub.3 H and/or --COOH groups. A liquid phase containing the carboxylic acid component, e.g. a fatty acid mixture, flows down the column reactor from one esterification tray to the next downward one against an upflowing alcohol vapour stream, e.g. methanol vapour. Relatively dry alcohol vapour is injected (21) into the bottom of the column reactor. Water of esterification is removed from the top of the column reactor in the vapour stream (26), whilst ester product is recovered (23) from the sump of the reactor. As the liquid flows down the trays it encounters progressively drier alocohol and the esterification equilibrium reaction is driven further and further towards 100% ester formation. A polishing reactor (304) operated under liquid phase conditions may follow the column reactor, the ester-containing product from which is mixed with further alcohol before admission to the polishing reactor.
A continuous process for the production of carboxylic acid esters by reaction of a carboxylic acid component selected from a group consisting of mono-, di- and polycarboxylic acids, anhydrides thereof, and mixtures thereof, and of an alcohol component selected from a group consisting of mono-, di- and polyhydric alcohols, phenols and mixtures thereof, in which the carboxylic acid component and alcohol component are passed in countercurrent through an esterification zone maintained under esterification conditions and containing a solid esterification catalyst selected from particulate ion exchange resins having sulphonic acid groups, carboxylic acid groups or both, (i) wherein the esterification zone comprises a column reactor provided with a plurality of esterification trays mounted one above another, each adapted to hold a predetermined liquid volume and a charge of particles of a solid esterification catalyst thereon, liquid downcomer means associated with each esterification tray adapted to allow liquid phase to pass down the column reactor from that esterification tray but to retain the particles of solid esterification catalyst thereon, and vapor upcomer means associated with each esterification tray adapted to allow vapor to enter that esterification tray from below and to agitate and maintain the suspension of the mixture of liquid and solid esterification catalyst on that esterification tray, each esterification tray having a floor that slopes towards a zone of turbulence under said vapor upcomer means to prevent formation of stagnant zones of particles of catalyst thereon, (ii) wherein the less volatile component of the carboxylic acid component and of the alcohol component is supplied in liquid phase to an upper part of the column reactor above the uppermost esterification tray, while the more volatile component of the carboxylic acid component and of the alcohol component is supplied in vapor form beneath the lowermost one of said plurality of esterification trays, (iii) wherein vapor comprising said more volatile component and water of esterification is recovered from an upper part of the column reactor, and (iv) wherein said carboxylic acid ester is recovered from a lower part of the column reactor.
Apparatus for use in the production of a carboxylic acid ester by reaction of a carboxylic acid component selected from a group consisting of mono-, di- and polycarboxylic acids, anhydrides thereof, and mixtures thereof, and of an alcohol component selected from a group consisting of mono-, di- and polyhydric alcohols, phenols and mixtures thereof, comprising a column reactor provided with a plurality of esterification trays mounted one above another, each adapted to hold a predetermined liquid volume and a charge of particles of a solid esterification catalyst thereon, liquid downcomer means associated with each esterification tray adapted to allow liquid phase to pass down the column reactor from that esterification tray but to retain the particles of solid esterification catalyst thereon, vapor upcomer means associated with each esterification tray adapted to allow vapor to enter that esterification tray from below and to agitate and maintain the suspension of the mixture of liquid and solid esterification catalyst on that esterification tray, each esterification tray having a floor that slopes towards a zone of turbulence under said vapor upcomer means to prevent formation of stagnant zones of particles of catalyst thereon, means for supplying the less volatile component of the carboxylic acid component and of the alcohol component in liquid phase to an upper part of the column reactor above the uppermost esterification tray, means for supplying the more volatile component of the carboxylic acid component and of the alcohol component in vapor form to a lower part of the column reactor below the lowermost esterification tray, means for recovering carboxylic acid ester from a lower part of the column reactor below the lowermost esterification tray, and means for recovering from an upper part of the column reactor above the uppermost esterification tray a vaporous stream comprising said more volatile component and water of esterification.
Dependencies are inferred from the claim text.