Abstract: A method is disclosed of producing a copolymer of polyethylene terephthalate and polyethylene naphthalate. The method comprises esterifying a combination of a diester of naphthalene, terephthalic acid, and ethylene glycol to produce an esterification reaction mixture that includes the alcohol byproduct of the naphthalene diester, distilling the reaction mixture to remove at least a portion of the esterification byproducts from the reaction mixture in the form of a vapor stream of which the majority component is water vapor and which includes the alcohol byproduct of the naphthalate ester in the vapor state, and combusting at least a portion of the vapor stream under conditions sufficient to decompose at least a portion of the alcohol byproduct present in the vapor stream.

Abstract: A process for destroying dioxane in a water vapor stream includes combusting the stream to decompose dioxane contained therein. The process is particularly useful for removal of dioxane from byproducts streams which result during the production of polyester.