Abstract: An oxidation process for the production of an aromatic carboxylic acid, said process comprising contacting in the presence of a catalyst, within a continuous flow reactor, one or more precursor(s) of the aromatic carboxylic acid with an oxidant, such contact being effected with said precursor(s) and the oxidant in an aqueous solvent comprising water under supercritical conditions or near supercritical conditions, wherein said catalyst comprises copper.

Abstract: A reactor for the oxidation of a precursor to an aromatic carboxylic acid or ester thereof in a liquid phase reaction mixture is disclosed. The reactor comprises an elongate vessel, substantially vertical in use, having an upper mixing element and a lower mixing element, characterised in that the upper mixing element is an axial pumping impeller and the lower mixing element is a radial pumping impeller. A process of producing a carboxylic acid or ester thereof in a reactor of the invention is also disclosed. In use, the configuration of mixing elements leads to three highly turbulent mixing zones. In a preferred embodiment of the process of the present invention oxidant, from one inlet, and solvent, precursor and catalyst, are introduced directly into a mixing zone. The highly turbulent mixing zones lead to rapid mass transfer suppressing the formation of unwanted, coloured by-products and reduced reactor fouling.

Abstract: The present invention relates to a method for increasing the production capacity of a conventional oxidation reactor for catalytic liquid phase oxidation of paraxylene by staging the oxidation reaction into a first high pressure and high solvent ratio reaction zone followed by the conventional reactor.

Abstract: Improved process for producing aromatic carboxylic acids by catalytic liquid phase oxidation of a corresponding precursor in a suitable solvent comprising feeding the reactants to a first oxidation reaction zone at high pressure and high solvent ratio, wherein uptake of oxygen is less than that required for full conversion of the precursor to its corresponding carboxylic acid, and then feeding the resulting reaction medium to a second oxidation reaction zone.

Abstract: A reactor for the oxidation of a precursor to an aromatic carboxylic acid or ester thereof in a liquid phase reaction mixture is disclosed. The reactor comprises an elongate vessel, substantially vertical in use, having an upper mixing element and a lower mixing element, characterised in that the upper mixing element is an axial pumping impeller and the lower mixing element is a radial pumping impeller. A process of producing a carboxylic acid or ester thereof in a reactor of the invention is also disclosed. In use, the configuration of mixing elements leads to three highly turbulent mixing zones. In a preferred embodiment of the process of the present invention oxidant, from one inlet, and solvent, precursor and catalyst, are introduced directly into a mixing zone. The highly turbulent mixing zones lead to rapid mass transfer suppressing the formation of unwanted, coloured by-products and reduced reactor fouling.

Abstract: The present invention relates to a method for increasing the production capacity of a conventional oxidation reactor for catalytic liquid phase oxidation of paraxylene by staging the oxidation reaction into a first high pressure and high solvent ratio reaction zone followed by the conventional reactor.

Abstract: Improved process for producing aromatic carboxylic acids by catalytic liquid phase oxidation of a corresponding precursor in a suitable solvent comprising feeding the reactants to a first oxidation reaction zone at high pressure and high solvent ratio, wherein uptake of oxygen is less than that required for full conversion of the precursor to its corresponding carboxylic acid, and then feeding the resulting reaction medium to a second oxidation reaction zone.

Abstract: The present invention relates to a method for increasing the production capacity of a conventional oxidation reactor for catalytic liquid phase oxidation of paraxylene by staging the oxidation reaction into a first high pressure and high solvent ratio reaction zone followed by the conventional reactor.