Compositions for carboxylic acid production and methods for making and using same

Abstract

An alcohol such as methanol is reacted with carbon monoxide in a liquid reaction medium including a catalyst, an alkyl iodide such as methyl iodide, alkyl acetate such as methyl acetate in specified proportions, an additive, and an effective amount of water, where the additive increases an ionic character of the hydrogen iodide bond and the effective amount of water is sufficient to facilitate carboxylic acid release after carbonylation at the catalyst and to reduce anhydride formation. The present reaction system not only provides an acid product at water levels considerable below levels currently used, but also provides unexpected reaction rates and unexpected high catalyst stability.

1 . A carbonylation composition comprising:
 a metal-containing catalyst,   an alcohol (ROH) or an alkyl acetate (AcOR),   an alkyl iodide (RI),   one or a plurality of hydrogen iodide (HI) solvating additives,   an effective amount of added water, and   carbon monoxide,   where the catalyst converts the alcohol into a carboxylic acid having one more carbon atom, the solvating additive increases an ionic character of the hydrogen iodide bond of hydrogen iodide formed during carbonylation reducing the effective amount of added water to a concentration at or below 4 wt. % and improves catalyst stability and where the effective amount of water is sufficient to facilitate the release of carboxylic acid after carbonylation of the alcohol/alkyl acetate and to reduce anhydride formation.   
   
   
       2 . The composition of  claim 1 , wherein the R group of the ROH or AcOR and RI is a linear alkyl group having between 1 and 6 carbon atoms. 
   
   
       3 . The composition of  claim 1 , wherein the solvating additive is selected from the group consisting of (1) polyols (R 1 (OH) n ), compounds including two or more hydroxy groups, (2) poly carboxylic acids (R 2 (COOH) n ), compounds including two or more carboxylic acid groups, (3) sulfones (R 3 SO 2 R 4 ), (4) oligomers, co-oligomers, polymers and co-polymers including at least one hydroxy containing monomer (poly(OH)), (5) oligomers, co-oligomers, polymers and co-polymers including at least one carboxylic acid containing monomer (poly(COOH)), (6) oligomers, co-oligomers, polymers and co-polymers including at least one sulfone containing monomer (poly(SO 2 )), and (7) mixtures thereof. 
   
   
       4 . The composition of  claim 3 , wherein the solvating additive has a boiling point or vaporization temperature at least 10° C. above a temperature of the product carboxylic acid. 
   
   
       5 . The composition of  claim 3 , wherein the solvating additive comprises a polyol having the formula R 1 (OH) n , where R 1  is selected from the group consisting of and n is an integer having a value between 1 and a maximum number replaceable hydrogen atoms and mixtures thereof. 
   
   
       6 . The composition of  claim 3 , wherein the solvating additive comprises poly carboxylic acids (R 2 (COOH) n ), compounds including two or more carboxylic acid groups, and mixtures thereof 
   
   
       7 . The composition of  claim 3 , wherein the solvating additive comprises sulfones (R 3 SO 2 R 4 ) and mixtures thereof. 
   
   
       8 . The composition of  claim 3 , wherein the solvating additive comprises oligomers, co-oligomers, polymers and co-polymers including at least one hydroxy containing monomer (poly(OH)), and mixtures thereof 
   
   
       9 . The composition of  claim 3 , wherein the solvating additive comprises oligomers, co-oligomers, polymers and co-polymers including at least one carboxylic acid containing monomer (poly(COOH)), and mixtures thereof 
   
   
       10 . The composition of  claim 3 , wherein the solvating additive comprises oligomers, co-oligomers, polymers and co-polymers including at least one sulfone containing monomer (poly(SO 2 )), and mixtures thereof. 
   
   
       11 . The composition of  claim 1 , wherein the catalyst is present in an amount sufficient to achieve a desired carbonylation reaction rate. 
   
   
       12 . The composition of  claim 1 , wherein the catalyst is present in an amount between about 200 and about 1200 ppm (about 2×10 −3  to about 13×10 −3  M). 
   
   
       13 . The composition of  claim 1 , wherein the catalyst is present in an amount between about 400 to about 1000 ppm (about 4×10 −3  to about 10×10 −3  M). 
   
   
       14 . The composition of  claim 1 , wherein the metal-containing catalyst is selected from the group consisting of rhodium based catalysts, iridium based catalysts, palladium based catalysts, or mixtures thereof. 
   
   
       15 . The composition of  claim 14 , wherein the metal-containing catalyst comprises a rhodium based catalyst. 
   
   
       16 . The composition of  claim 15 , wherein the metal-containing catalyst comprises rhodium metal, rhodium salts, rhodium oxides, rhodium acetates, organo-rhodium compounds, coordination compounds of rhodium, or mixtures or combinations thereof. 
   
   
       17 . The composition of  claim 16 , wherein the metal-containing catalyst comprises a rhodium-containing compound selected from the group consisting of RhCl 3 ; RhBr 3 ; RhI 3 ; RhCl 3 .3H 2 O; RhBr 3 .3H 2 O; RhI 3 .3H 2 O; Rh 2 (CO) 4 Cl 2 ; Rh 2 (CO) 4 Br 2 ; Rh 2 (CO) 4 I 2 ; Rh 2 (CO) 8 ; Rh(CH 3 CO 2 ) 2 ; Rh(CH 3 CO 2 ) 3 ; Rh[(C 6 H 5 ) 3 P] 2 (CO)I; Rh[(C 6 H 5 P)] 2 (CO)Cl; Rh metal; Rh(NO 3 ) 3 ; Rh(SnCl 3 )[(C 6 H 5 ) 3 P] 2 ; RhCl(CO)[(C 6 H 5 ) 3 As] 2 ; RhI(CO)[(C 6 H 5 ) 3 Sb] 2 ; [Y][Rh(CO) 2 X 2 ], where X is Cl − , Br −  or I − ; and Y is a cation selected from the group consisting of positive ions from Group IA of the Periodic Table of Elements, such as H, Li, Na, K, or Y is a quaternary ion of N, As or P; Rh[(C 6 H 5 ) 3 P] 2 (CO)Br; Rh[(n-C 4 H 9 ) 3 P] 2 (CO)Br; Rh[(n-C 4 H 9 ) 3 P] 2 (CO)I; RhBr[(C 6 H 5 ) 3 P] 3 ; RhI[(C 6 H 5 ) 3 P] 3 ; RhCl[(C 6 H 5 ) 3 P] 3 ; RhCl[(C 6 H 5 ) 3 P] 3 H 2 ; [(C 6 H 5 ) 3 P] 3 Rh(CO)H; Rh 2 O 3 ; [Rh(C 3 H 4 ) 2 Cl] 2 ; K 4 Rh 2 Cl 2 (SnCl 2 ) 4 ; K 4 Rh 2 Br 2 (SnBr 3 ) 4 ; [H][Rh(CO) 2 I 2 ]; K 4 Rh 2 I 2 (SnI 2 ) 4 , and the like and mixtures or combinations thereof. 
   
   
       18 . The composition of  claim 17 , wherein the metal-containing catalyst comprises a rhodium-containing compound selected from the group consisting of Rh 2 (CO) 4 I 2 , Rh 2 (CO) 4 Br 2 , Rh 2 (CO) 4 Cl 2 , Rh(CH 3 CO 2 ) 2 , Rh(CH 3 CO 2 ) 3 , [H][Rh(CO) 2 I 2 ] or mixtures or combinations thereof. 
   
   
       19 . The composition of  claim 18 , wherein the metal-containing catalyst comprises a rhodium-containing compound selected from the group consisting of [H][Rh(CO) 2 I 2 ], Rh(CH 3 CO 2 ) 2 , Rh(CH 3 CO 2 ) 3  or mixtures or combinations thereof. 
   
   
       20 . The composition of  claim 14 , wherein the metal-containing catalyst comprises an iridium based catalyst. 
   
   
       21 . The composition of  claim 20 , wherein an iridium-containing compound selected from the group consisting of IrCl 3 , IrI 3 , IrBr 3 , [Ir(CO) 2 I] 2 , [Ir(CO) 2 Cl] 2 , [Ir(CO) 2 Br] 2 , [Ir(CO).sub.4I 2 ] − H + , [Ir(CO) 2 ] − H + , [Ir(CO).sup.2I 2 ] − H + , [Ir(CH 3 )I 3 (CO) 2 ] − H + , Ir 4 (CO) 12 , IrCl 3 .4H 2 O, IrBr 3 .4H 2 O, Ir 3 (CO) 12 , Ir 2 O 3 , IrO 2 , Ir(acac)(CO) 2 , Ir(acac) 3 , Ir(Ac) 3 , [Ir 3 O(OAc) 6 (H 2 O) 3 ][OAc], and H 2 [IrCl 6 ]. 
   
   
       22 . The composition of  claim 21 , wherein an iridium-containing compound selected from the group consisting of acetates, oxalates, acetoacetates, and mixtures thereof. 
   
   
       23 . The composition of  claim 1 , wherein the iridium-based catalyst includes a co-catalyst including metals and metal compounds selected from the group consisting of osmium, rhenium, ruthenium, cadmium, mercury, zinc, gallium, indium, and tungsten, their compounds, and mixtures thereof. 
   
   
       24 . A system for producing carboxylic acids comprising:
 a reaction subsystem including at least one reactor vessel charged with a liquid reaction media comprising:
 a metal-containing catalyst, 
 an alcohol (ROH) forming a corresponding alkyl acetate (AcOR) in situ, 
 an alkyl iodide (RI), 
 one or a plurality of hydrogen iodide (HI) solvating additives, 
 an effective amount of added water, and 
 an effective amount of added water; 
   a carbon monoxide supply subsystem for supplying carbon monoxide to the at least one reactor vessel, and   a carboxylic acid purification and recycle subsystem for purifying the carboxylic acid product and recycling recovered alkyl acetate, alcohol, and alkyl iodide to the at least on reactor vessel,   where the catalyst converts the alcohol into a carboxylic acid having one more carbon atom, the solvating additive increases an ionic character of the hydrogen iodide bond of hydrogen iodide formed during carbonylation reducing the effective amount of added water to a concentration at or below 4 wt. % and improves catalyst stability and where the effective amount of water is sufficient to facilitate the release of carboxylic acid after carbonylation of the alcohol/alkyl acetate and to reduce anhydride formation.   
   
   
       25 . A method for producing carboxylic acids comprising:
 charging a reactor vessel with a liquid reaction media comprising:
 a metal-containing catalyst, 
 an alcohol (ROH) forming a corresponding alkyl acetate (AcOR) upon addition to the 
 reaction media, 
 an alkyl iodide (RI), 
 one or a plurality of hydrogen iodide (HI) solvating additives, 
 an effective amount of added water, and 
   supplying carbon monoxide to the reaction vessel;   removing the media or a portion thereof,   separating the low boiling components including the carboxylic acid to form a crude carboxylic acid product and,   recycling the high boiling components back to the reactor vessel;   separating the low boiling components from the crude acid product to form a purified carboxylic acid product, and   returning other low boiling components to the reactor vessel,   
     where the catalyst converts the alcohol into a carboxylic acid having one more carbon atom, the solvating additive increases an ionic character of the hydrogen iodide bond of hydrogen iodide formed during carbonylation reducing the effective amount of added water to a concentration at or below 4 wt. % and improves catalyst stability and where the effective amount of water is sufficient to facilitate the release of carboxylic acid after carbonylation of the alcohol/alkyl acetate and to reduce anhydride formation.