Abstract: A process for regenerating a silica-supported depleted alkali metal catalyst is described. The level of alkali metal on the depleted catalyst is at least 0.5 mol % and the silica support is a zero-gel. The process comprises the steps of contacting the silica supported depleted alkali metal catalyst with a solution of a salt of the alkali metal in a solvent system that has a polar organic solvent as the majority component. A re-impregnated catalyst prepared by the process of the invention any comprising a silica zero-gel support and a catalytic metal selected from an alkali metal in the range 0.5-5 mol % on the catalyst, wherein the surface area of the silica support is <180 m2/g is also described. The invention is applicable to a process for preparing an ethylenically unsaturated acid or ester comprising contacting an alkanoic acid or ester of the formula R1—CH2—COOR3, with formaldehyde or a suitable source of formaldehyde.

Abstract: A process for the reactivation of an acidic ion exchange resin is described. The invention relates to the treatment of an at least partially deactivated resin which has been deactivated by contact with an impure ethylenically unsaturated acid or ester containing target impurities. The reactivation includes the step of contacting the at least partially deactivated resin with an alcohol to thereby increase the activity thereof. The invention extends to reactivating a resin deactivated by contact with an impure ethylenically unsaturated acid, ester or nitrile containing target impurities by contacting the at least partially deactivated resin with an alcohol and a carboxylic acid to thereby increase the activity thereof. A reactivated resin and a process for preparing and purifying an ethylenically unsaturated acid or ester of the following formula: R1—C(?(CH2)m)—COOR2 are also described.

Abstract: A process for regenerating a silica-supported depleted alkali metal catalyst is described. The level of alkali metal on the depleted catalyst is at least 0.5 mol % and the silica support is a zero-gel. The process comprises the steps of contacting the silica supported depleted alkali metal catalyst with a solution of a salt of the alkali metal in a solvent system that has a polar organic solvent as the majority component. A re-impregnated catalyst prepared by the process of the invention any comprising a silica zero-gel support and a catalytic metal selected from an alkali metal in the range 0.5-5 mol % on the catalyst, wherein the surface area of the silica support is <180 m2/g is also described. The invention is applicable to a process for preparing an ethylenically unsaturated acid or ester comprising contacting an alkanoic acid or ester of the formula R1—CH2—COOR3, with formaldehyde or a suitable source of formaldehyde.

Abstract: A process for regenerating a silica-supported depleted alkali metal catalyst is described. The level of alkali metal on the depleted catalyst is at least 0.5 mol % and the silica support is a zero-gel. The process comprises the steps of contacting the silica supported depleted alkali metal catalyst with a solution of a salt of the alkali metal in a solvent system that has a polar organic solvent as the majority component. A re-impregnated catalyst prepared by the process of the invention any comprising a silica zero-gel support and a catalytic metal selected from an alkali metal in the range 0.5-5 mol % on the catalyst, wherein the surface area of the silica support is <180 m2/g is also described. The invention is applicable to a process for preparing an ethylenically unsaturated acid or ester comprising contacting an alkanoic acid or ester of the formula R1—CH2—COOR3, with formaldehyde or a suitable source of formaldehyde.

Abstract: A process for regenerating a silica-supported depleted alkali metal catalyst is described. The level of alkali metal on the depleted catalyst is at least 0.5 mol % and the silica support is a zero-gel. The process comprises the steps of contacting the silica supported depleted alkali metal catalyst with a solution of a salt of the alkali metal in a solvent system that has a polar organic solvent as the majority component. A re-impregnated catalyst prepared by the process of the invention any comprising a silicazero-gel support and a catalytic metal selected from an alkali metal in the range 0.5-5 mol % on the catalyst, wherein the surface area of the silica support is <180 m2/g is also described. The invention is applicable to a process for preparing an ethylenically unsaturated acid or ester comprising contacting an alkanoic acid or ester of the formula R1—CH2—COOR3, with formaldehyde or a suitable source of formaldehyde.

Abstract: A process for purifying methyl methacrylate (MMA) is described. The process involves contacting liquid MMA having impurities therein with a sulphonic acid resin, in the presence of formaldehyde or a suitable source of methylene or ethylene of formula I. R5 and R6 are independently selected from C1-C12 hydrocarbons or H; X is either O or S; n is an integer from, 1 to 100; and m is 1 or 2: The compound of formula I may be suitable source of formaldehyde.

Abstract: A process for the reactivation of an acidic ion exchange resin is described. The invention relates to the treatment of an at least partially deactivated resin which has been deactivated by contact with an impure ethylenically unsaturated acid or ester containing target impurities. The reactivation includes the step of contacting the at least partially deactivated resin with an alcohol to thereby increase the activity thereof. The invention extends to reactivating a resin deactivated by contact with an impure ethylenically unsaturated acid, ester or nitrile containing target impurities by contacting the at least partially deactivated resin with an alcohol and a carboxylic acid to thereby increase the activity thereof. A reactivated resin and a process for preparing and purifying an ethylenically unsaturated acid or ester of the following formula: R1—C(?(CH2)m)—COOR2 are also described.

Abstract: A process for the reactivation of an acidic ion exchange resin is described. The invention relates to the treatment of an at least partially deactivated resin which has been deactivated by contact with an impure ethylenically unsaturated acid or ester containing target impurities. The reactivation includes the step of contacting the at least partially deactivated resin with an alcohol to thereby increase the activity thereof. The invention extends to reactivating a resin deactivated by contact with an impure ethylenically unsaturated acid, ester or nitrile containing target impurities by contacting the at least partially deactivated resin with an alcohol and a carboxylic acid to thereby increase the activity thereof. A reactivated resin and a process for preparing and purifying an ethylenically unsaturated acid or ester of the following formula: —R1—C(?(CH2)m)—COOR2 are also described.

Abstract: A production process for the manufacture of ethylenically unsaturated acids or esters thereof is described. The process includes the steps of reaction of an alkanoic acid, or ester of an alkanoic acid, of the formula R3—CH2—COOR4 where R3 and R4 are each independently hydrogen or an alkyl group, in the presence of a catalyst system to produce an ethylenically unsaturated acid or ester product. The process is characterised in that the acid or ester product is subsequently contacted with a dienophile to thereby remove discolouration therefrom. An ethylenically unsaturated acid or ester crude product purification process is also described.

Abstract: A process for the reactivation of an acidic ion exchange resin is described. The invention relates to the treatment of an at least partially deactivated resin which has been deactivated by contact with an impure ethylenically unsaturated acid or ester containing target impurities. The reactivation includes the step of contacting the at least partially deactivated resin with an alcohol to thereby increase the activity thereof. The invention extends to reactivating a resin deactivated by contact with an impure ethylenically unsaturated acid, ester or nitrile containing target impurities by contacting the at least partially deactivated resin with an alcohol and a carboxylic acid to thereby increase the activity thereof. A reactivated resin and a process for preparing and purifying an ethylenically unsaturated acid or ester of the following formula:— R1—C(?(CH2)—COOR2 are also described.

Abstract: A process for purifying methyl methacrylate (MMA) is described. The process involves contacting liquid MMA having impurities therein with a sulphonic acid resin, in the presence of formaldehyde or a suitable source of methylene or ethylene of formula I. R5 and R6 are independently selected from C1-C12 hydrocarbons or H; X is either O or S; n is an integer from, 1 to 100; and m is 1 or 2: The compound of formula I may be suitable source of formaldehyde.

Abstract: A production process for the manufacture of ethylenically unsaturated acids or esters thereof is described. The process includes the steps of reaction of an alkanoic acid, or ester of an alkanoic acid, of the formula R3—CH2—COOR4 where R3 and R4 are each independently hydrogen or an alkyl group, in the presence of a catalyst system to produce an ethylenically unsaturated acid or ester product. The process is characterised in that the acid or ester product is subsequently contacted with a dienophile to thereby remove discolouration therefrom. An ethylenically unsaturated acid or ester crude product purification process is also described.