Abstract:
In the process for the conversion of maleic acid to gamma-butyrolactone. 1.4-butanediol and/or tetrahydrofuran, a feedstream comprising maleic acid is hydrogenated in a first hydrogenation zone to produce a reaction product comprising succinic acid and unreacted hydrogen which is then supplied to a second hydrogenation zone, where succinic acid is converted to 1,4-butanediol, the temper atures of the feedstream comprising maleic acid and the first hydrogenation zone are controlled such that the temperature of mal eic acid in the feedstream and the first hydrogenation zone does not exceed about 130 DEG C, thereby minimizing the corrosive effects of the maleic acid and prolonging reactor life and improving overall process economics.
Abstract:
In the process for the conversion of maleic acid to gamma-butyrolactone, 1.4-butanediol and/or tetrahydrofuran, a feedstream comprising maleic acid is hydrogenated in a first hydrogenation zone to produce a reaction product comprising succinic acid and unreacted hydrogen which is then supplied to a second hydrogenation zone, where succinic acid is converted to 1,4-butanediol, the temperatures of the feedstream comprising maleic acid and the first hydrogenation zone are controlled such that the temperature of maleic acid in the feedstream and the first hydrogenation zone does not exceed about 130° C., thereby minimizing the corrosive effects of the maleic acid and prolonging reactor life and improving overall process economics.
Abstract:
El ácido maléico, el anhídrido maléico u otros precursores hidrogenables pueden hidrogenarse catalíticamente para dar 1,4-butanodiol y tetrahidrofurano. Se ha descubierto que se logran altos rendimientos de 1,4-butanodiol cuando los catalizadores de hidrogenacion comprenden paladio, plata y renio sobre un soporte de carbon, y se preparan mediante los pasos de: (i) impregnar un soporte de carbon con una fuente de paladio, plata y renio, en donde la fuente de paladio, plata y renio es por lo menos una solucion; (ii) después de cada etapa de impregnacion, secar el soporte de carbon impregnado para retirar el solvente; (iii) calentar el soporte de carbon impregnado a una temperatura de entre aproximadamente 100 degree C y 350 degree C, bajo condiciones reductoras. El paladio en el catalizador está presente en forma de cristalitos que tienen un tamaño de partículas menor a 10 nm.
Abstract:
Tetrahydrofuran and gamma-butyrolactone are prepared from at least one of maleic anhydride or succinic anhydride by catalytically hydrogenating vaporous maleic anhydride or vaporous succinic anhydride in the presence of hydrogen in contact with a catalyst comprising an essentially inert, at least partially porous support having an outer surface, and a catalytically active oxide material coating onto the outer surface of the support which strongly adheres to the support, wherein the catalytically active oxide material comprises the mixed oxides of copper, zinc and aluminum.
Abstract:
Tetrahydrofuran and gamma-butyrolactone are prepared from at least one of maleic anhydride or succinic anhydride by catalytically hydrogenating vaporous maleic anhydride or vaporous succinic anhydride in the presence of hydrogen in contact with a catalyst comprising an essentially inert, at least partially porous support having an outer surface, and a catalytically active oxide material coating onto the outer surface of the support which strongly adheres to the support, wherein the catalytically active oxide material comprises the mixed oxides of copper, zinc and aluminum.
Abstract:
In the process for the conversion of maleic acid to gamma-butyrolactone. 1.4 - butanediol and/or tetrahydrofuran, a feedstream comprising maleic acid is hydrogenated in a first hydrogenation zone to produce a reaction product comprising succinic acid and unreacted hydrogen which is then supplied to a second hydrogenation zone, where succinic acid is converted to 1,4-butanedio l, the temper atures of the feedstream comprising maleic acid and the first hydrogenation zone are controlled such that the temperature of maleic acid i n the feedstream and the first hydrogenation zone does not exceed about 130 ~C , thereby minimizing the corrosive effects of the maleic acid and prolonging reactor life and improving overall process economics.
Abstract:
Prodn. of tetrahydrofuran (THF) and 1,4-butanediol (BDO), contg. a major portion of BDO, comprises catalytic hydrogenation of an hydrogenatable precursor in contact with an H2-contg. gas and a carbon-supported Pd, Ag and Re-contg. hydrogenation catalyst prepd. by: i) impregnating the C support with a source of Pd, Ag and Re, in one or more steps, using at least one soln. of the metal sources; ii) drying the impregnated support to remove solvent after each impregnation step; iii) heating the impregnated support at 100-350 deg.C under reducing conditions.