Terephthalic Acid from Toluene and Carbon Monoxide via p-Tolualdehyde

Mitsubishi Gas Chemical Co. has recently announced procedures for manufacture of p-tolualdehyde from toluene and carbon monoxide, and of terephthalic acid from p-tolualdehyde. A preliminary process design and cost estimates on the aldehyde are presented in this review, and economic figures on manufacture of fiber-grade terephthalic acid by oxidation of the aldehyde are compared with the conventional p-xylene oxidation process.

The comparison indicates that the p-tolualdehyde route may be about competitive with p-xylene oxidation, but is unlikely to offer an appreciable economic advantage.