Abstract: Methods for reducing the fouling of process equipment used in the manufacture of aromatic compounds such as dimethyl-2,6-naphthalenedicarboxylate are disclosed. The methods require treating manufacturing process streams with a metal complexing agent. Novel compositions useful in the manufacture of aromatic materials such as dimethyl-2,6-naphthalenedicarboxylate also are disclosed.

Abstract: Economical processes are disclosed for preparing relatively pure polycarboxylic acid from typical crude products of liquid phase oxidation, which do not involve intermediate steps of ester formation or require any alkanol containing solvent, for purification of "crude" polycarboxylic acid containing impurities which include one or more monofunctional aromatic compounds, trifunctional aromatic compounds, and/or color causing organic compounds formed by oxidation of a corresponding substituted aromatic compound in a liquid phase, e.g. 2,6-naphthalene dicarboxylic acid by liquid phase oxidation of 2,6-dimethyl naphthalene. The invention provides integrate processes which comprise reacting crude oxidation product with a polyalkyl amine amine, e.g. trialkylamine, forming an aqueous solution of the salts thus obtained, separating deleterious compounds from the solution, and recovering the polyalkyl amine and a relatively pure polycarboxylic acid product.

Abstract: A continuous process for preparing a dialkylester of a naphthalenedicarboxylic acid comprising passing a liquid phase reaction mixture comprising a low molecular weight alcohol, a naphthalenedicarboxylic acid and a dialkylester of a naphthalenedicarboxylic acid at an elevated temperature through series arranged reaction zones while introducing a naphthalenedicarboxylic acid and a low molecular weight alcohol to an upstream reaction zone, agitating at least one reaction zone, and removing a liquid product mixture comprising the dialkylester of the naphthalenedicarboxylic acid produced by the reaction of the naphthalenedicarboxylic acid with the low molecular weight alcohol from a downstream reaction zone.

Abstract: Disclosed is a method for preparing an aromatic carboxylic acid comprising oxidizing in the liquid phase an aromatic feed compound containing at least one alkyl or acyl group with a molecular oxygen-containing gas, in a solvent comprising a low molecular weight aliphatic carboxylic acid, and in the presence of a heavy metal oxidation catalyst, thereby forming an oxidation reaction product mixture comprising an aromatic carboxylic acid; subsequently heating the oxidation reaction product mixture at a temperature of at least about 500.degree. F. to form a second product mixture; and recovering from the second product mixture the aromatic carboxylic acid. The method of this invention provides for purer, larger particle size aromatic carboxylic acid product.

Abstract: A process for preparing purified dimethyl-2,6-naphthalenedicarboxylate by the esterification of 2,6-naphthalenedicarboxylic acid is disclosed and which process provides for the efficient removal of the mono methyl ester of 2,6-naphthalenedicarboxylic acid produced during the esterification reaction.