This disclosure provides for catalyst systems and processes for forming an α,β-unsaturated carboxylic acid or a salt thereof. In an aspect, the catalyst system can comprise: a transition metal precursor comprising a Group 8-11 transition metal and at least one first ligand; optionally, at least one second ligand; an olefin; carbon dioxide (CO.sub.2); a diluent; and an oxoacid anion-substituted polyaromatic resin comprising a sulfonated polyaromatic resin, a phosphonated polyaromatic resin, a sulfinated polyaromatic resin, a thiosulfonated, or a thiosulfinated polyaromatic resin, and further comprising associated metal cations. Methods of regenerating the polyaromatic resin with associated metal cations are described.

There is disclosed a method of forming chlorine dioxide comprising passing chlorous acid through a membrane including a catalyst suitable to catalyse the formation of chlorine dioxide from chlorous acid. There is also disclosed a membrane suitable for forming an aqueous solution of chlorine dioxide comprising a catalyst suitable to catalyse the formation of chlorine dioxide from chlorous acid or alkali metal chlorite.

There is disclosed a method of forming chlorine dioxide comprising passing chlorous acid through a membrane including a catalyst suitable to catalyse the formation of chlorine dioxide from chlorous acid. There is also disclosed a membrane suitable for forming an aqueous solution of chlorine dioxide comprising a catalyst suitable to catalyse the formation of chlorine dioxide from chlorous acid or alkali metal chlorite.

A method for producing dicarboxylic acid. The method includes: subjecting a raw material system including a cyclic olefin and a lower monocarboxylic acid to an addition reaction in the presence of an addition reaction catalyst to generate an intermediate product system including cyclic carboxylic acid ester; and subjecting the intermediate product system including cyclic carboxylic acid ester to a ring-opening and oxidation reaction in the presence of an oxidant and an oxidation catalyst to generate a corresponding dicarboxylic acid product. The addition reaction in the dicarboxylic acid synthesis route achieves a high single-pass conversion rate, and the selectivity of the corresponding cyclic carboxylic acid ester is high. The addition-oxidation synthesis route achieves faster reaction rates for both the addition reaction and oxidation reaction, and high yield of corresponding dicarboxylic acid product. The addition-oxidation based synthesis route is suitable for continuous, stable and large-scale production of corresponding dicarboxylic acid product.

A method for producing dicarboxylic acid. The method includes: subjecting a raw material system including a cyclic olefin and a lower monocarboxylic acid to an addition reaction in the presence of an addition reaction catalyst to generate an intermediate product system including cyclic carboxylic acid ester; and subjecting the intermediate product system including cyclic carboxylic acid ester to a ring-opening and oxidation reaction in the presence of an oxidant and an oxidation catalyst to generate a corresponding dicarboxylic acid product. The addition reaction in the dicarboxylic acid synthesis route achieves a high single-pass conversion rate, and the selectivity of the corresponding cyclic carboxylic acid ester is high. The addition-oxidation synthesis route achieves faster reaction rates for both the addition reaction and oxidation reaction, and high yield of corresponding dicarboxylic acid product. The addition-oxidation based synthesis route is suitable for continuous, stable and large-scale production of corresponding dicarboxylic acid product.

Provided is a method of cleaning a collection of resin beads, wherein the method comprises bringing the collection of resin beads into contact with an aqueous solution, wherein the aqueous solution comprises one or more dissolved amine compounds, wherein the collection of resin beads comprises polymer that comprises attached carboxylic acid groups or sulfonic acid groups or a mixture thereof.

This disclosure provides for catalyst systems and processes for forming an ,-unsaturated carboxylic acid or a salt thereof. In an aspect, the catalyst system can comprise: a transition metal precursor comprising a Group 8-11 transition metal and at least one first ligand; optionally, at least one second ligand; an olefin; carbon dioxide (CO.sub.2); a diluent; and an oxoacid anion-substituted polyaromatic resin comprising a sulfonated polyaromatic resin, a phosphonated polyaromatic resin, a sulfinated polyaromatic resin, a thiosulfonated, or a thiosulfinated polyaromatic resin, and further comprising associated metal cations. Methods of regenerating the polyaromatic resin with associated metal cations are described.

This disclosure provides for catalyst systems and processes for forming an ,-unsaturated carboxylic acid or a salt thereof. In an aspect, the catalyst system can comprise: a transition metal precursor comprising a Group 8-11 transition metal and at least one first ligand; optionally, at least one second ligand; an olefin; carbon dioxide (CO.sub.2); a diluent; and an oxoacid anion-substituted polyaromatic resin comprising a sulfonated polyaromatic resin, a phosphonated polyaromatic resin, a sulfinated polyaromatic resin, a thiosulfonated, or a thiosulfinated polyaromatic resin, and further comprising associated metal cations. Methods of regenerating the polyaromatic resin with associated metal cations are described.

Chlorous acid is generated from a chlorite salt precursor, a chlorate salt precursor, or a combination of both by ion exchange. The ion exchange material facilitates the generation of chlorous acid by simultaneously removing unwanted cations from solution and adding hydrogen ion to solution. Chlorine dioxide is generated in a controlled manner from chlorous acid by catalysis. Chlorine dioxide can be generated either subsequent to the generation of chlorous acid or simultaneously with the generation of chlorous acid. For catalysis of chlorous acid to chlorine dioxide, the chlorous acid may be generated by ion exchange or in a conventional manner. Ion exchange materials are also used to purify the chlorous acid and chlorine dioxide solutions, without causing degradation of said solutions, to exchange undesirable ions in the chlorous acid and chlorine dioxide solutions with desirable ions, such as stabilizing ions, and to adjust the pH of chlorous acid and chlorine dioxide solutions.

Provided is a process for producing 2,2-bis(4-hydroxyphenyl)propane, comprising condensing phenol with acetone in the presence of an acid catalyst; wherein the acid catalyst comprises a collection of sulfonated polymeric beads, wherein the sulfonated polymeric beads comprise (i) 75 to 99% by weight, based on the weight of the bead, polymerized units of monofunctional vinyl monomer, and (ii) 1 to 25% by weight, based on the weight of the bead, polymerized units of multifunctional vinyl monomer; wherein 90% or more of the beads by volume are uniform beads.