Chemisorption of ethyl acetate during hydrogenation of acetic acid to ethanol

Abstract

A hydrogenation catalyst and process using the catalyst for converting a mixture comprising acetic acid and ethyl acetate to ethanol at a first temperature, and the catalyst desorbs ethyl acetate, in the absence of hydrogen, at a second temperature that is greater than the first temperature. The catalyst has a suitable chemisorption of ethyl acetate at the first temperature in the absence of hydrogen. In one embodiment, the first temperature ranges from 125° C. to 350° C. and the second temperature ranges from 300° C. to 600° C. The catalyst comprises one or more active metals or oxide thereof on a support that comprises tungsten or an oxide thereof. The one or more active metals are selected from the group consisting of cobalt, copper, gold, iron, nickel, palladium, platinum, iridium, osmium, rhenium, rhodium, ruthenium, tin, zinc, lanthanum, cerium, manganese, chromium, vanadium, and molybdenum.

1 . A hydrogenation catalyst for converting a mixture comprising acetic acid and ethyl acetate to ethanol at a first temperature, the catalyst comprising one or more active metals or oxide thereof on a support that comprises tungsten or an oxide thereof, wherein the one or more active metals are selected from the group consisting of cobalt, copper, gold, iron, nickel, palladium, platinum, iridium, osmium, rhenium, rhodium, ruthenium, tin, zinc, lanthanum, cerium, manganese, chromium, vanadium, and molybdenum; and wherein the catalyst desorbs ethyl acetate, in the absence of hydrogen, at a second temperature that is greater than the first temperature. 
     
     
         2 . The catalyst of  claim 1 , wherein the catalyst has a chemisorption of ethyl acetate at the first temperature in the absence of hydrogen. 
     
     
         3 . The catalyst of  claim 1 , wherein the first temperature ranges from 125° C. to 350° C. 
     
     
         4 . The catalyst of  claim 1 , wherein the second temperature ranges from 300° C. to 600° C. 
     
     
         5 . The catalyst of  claim 1 , wherein the support is selected from the group consisting of silica, alumina, titania, silica/alumina, pyrogenic silica, high purity silica, zirconia, carbon, zeolites and mixtures thereof. 
     
     
         6 . The catalyst of  claim 1 , wherein the support is present in an amount from 25 wt. % to 99 wt. %. 
     
     
         7 . The catalyst of  claim 1 , wherein the support further comprises a support modifier. 
     
     
         8 . The catalyst of  claim 7 , wherein the support modifier is present in an amount from 0.1 to 50 wt. %. 
     
     
         9 . (canceled) 
     
     
         10 . (canceled) 
     
     
         11 . The catalyst of  claim 7 , wherein the support modifier is selected from the group consisting of TiO 2 , ZrO 2 , Nb 2 O 5 , Ta 2 O 5 , Al 2 O 3 , B 2 O 3 , P 2 O 5 , Sb 2 O 3 , MoO 3 , Fe 2 O 3 , Cr 2 O 3 , V 2 O 5 , MnO 2 , CuO, Co 2 O 3 , and Bi 2 O 3 . 
     
     
         12 . The catalyst of  claim 1 , wherein the one or more active metals are present in an amount from amount of 0.1 wt. % to 25 wt. %, based on the total weight of the catalyst. 
     
     
         13 . The catalyst of  claim 1 , wherein the one or more active metals or oxide thereof comprise a first metal or oxide thereof selected from the group consisting of rhodium, rhenium, ruthenium, platinum, palladium, osmium, iridium and gold, and a second metal or oxide thereof selected from the group consisting of copper, iron, cobalt, nickel, zinc, and molybdenum; a third metal or oxide thereof selected from the group consisting of copper, molybdenum, tin, chromium, iron, cobalt, vanadium, palladium, platinum, lanthanum, cerium, manganese, ruthenium, rhenium, gold, and nickel and further wherein the third metal and the second metal are different than the first metal. 
     
     
         14 . A hydrogenation catalyst for converting a mixture comprising acetic acid and ethyl acetate to ethanol at a first temperature, the catalyst comprising a first metal or oxide thereof, a second metal or oxide thereof, and a third metal or oxide thereof, on a support, provided that the first metal is reduced after hydrogen treatment and the second and third metals are partly reduced after hydrogen treatment; the first metal or oxide thereof is selected from the group consisting of rhodium, rhenium, ruthenium, platinum, palladium, osmium, iridium and gold, and the second metal or oxide thereof is selected from the group consisting of copper, iron, cobalt, nickel, zinc, and molybdenum; the third metal or oxide thereof is selected from the group consisting of copper, molybdenum, tin, chromium, iron, cobalt, vanadium, palladium, platinum, lanthanum, cerium, manganese, ruthenium, rhenium, gold, and nickel and further wherein the third metal and the second metal are different than the first metal; and wherein the hydrogen treated catalyst has an ethyl acetate desorption peak at a second temperature that is greater than an ethyl acetate desorption peak at the first temperature. 
     
     
         15 . A hydrogenation catalyst for converting a mixture comprising acetic acid and ethyl acetate to ethanol at a first temperature, the catalyst comprising one or more active metals on a support, wherein the one or more active metals are selected from the group consisting of cobalt, copper, gold, iron, nickel, palladium, platinum, iridium, osmium, rhenium, rhodium, ruthenium, tin, zinc, lanthanum, cerium, manganese, chromium, vanadium, and molybdenum; and wherein the catalyst has an ethyl acetate adsorption capacity (Type III+IV) that is from 30 to 70 μmol/g cat  at a second temperature that is greater than the first temperature. 
     
     
         16 . The catalyst of  claim 15 , wherein the support comprises tungsten or an oxide thereof. 
     
     
         17 - 28 . (canceled)