Published September 1991
Du Pont has developed a route for making tetrahydrofuran (THF), which entails hydrogenating aqueous maleic acid in the presence of a rhenium-modified palladium catalyst.
This process is being developed in conjunction with a new n-butane based maleic anhydride process that DuPont is developing jointly with Monsanto (see PEP Report 46C, Malic Anhydride). This review presents a conceptual process design and estimated economics for the production of THF from maleic acid, based mainly on patents to DuPont. The main advantage of DuPont's new process is the lower raw material costs. SRI's estimated product value for THF, including a 25%/yr pretax return on investment, is slightly lower for the DuPont process than for the traditional process that starts with 1,4-butanediol (from either acetylene and formaldehyde, or allyl alcohol).