Trimellitic acid anhydride recovery - by steam stripping and fractionation of pseudocumene oxidn effluent

摘要

Fluid effluent from pseudocumene oxidn, with O2 in the presence of acetic acid, is subject to simultaneous stripping of the reaction medium, thermal conversion of its trimellitic acid content to crude trimellitic anhydride (I) and steam stripping at atmos pressure followed by continuous fractionation of crude (I). (I) is useful for the commercial prepn. of esters, alkyl resins and urethane-like foams, or as an inter. for the 4-acid halide from which poly- (amide-imidi) resin can be made.