Process for catalyst recovery from hydrocyanation product mixtures

1. A process for recovering diphosphite-containing compounds from a mixture comprising diphosphite-containing compounds and organic mononitriles and organic dinitriles, using liquid-liquid extraction, wherein the molar ratio of organic mononitrile present to organic dinitrile is from about 0.65 to about 2.5 and wherein the extraction solvent is a saturated or unsaturated alkane or saturated or unsaturated cycloalkane.

2. A process according to claim 1 wherein the molar ratio of organic mononitrile to organic dinitrile is from about 1.0 to about 1.5.

3. A process for recovering diphosphite-containing compounds from a mixture comprising diphosphite-containing compounds, organic mononitriles and dinitriles, and Lewis acid, using liquid-liquid extraction, wherein the molar ratio of organic mononitrile present to organic dinitrile is from about 0.01 to about 2.5 and wherein the mixture is treated with a Lewis base compound selected from the group consisting of monodentate phosphite ligand alcohol, water, organoamines, ammonia, and, basic resin prior to the liquid extraction, and wherein the solvent is a saturated or unsaturated alkane or saturated or unsaturated cycloalkane.

4. A process according to claim 1 , 2 , or 3 wherein the diphosphite-containing compound is a Ni complex with a diphosphite ligand selected from the group consisting of:

(R 1 O) 2 P(OZO)P(OR 1 ) 2 ,  I

wherein in diphosphite ligand structures I, II, and III, R 1 is phenyl, unsubstituted or substituted with one or more C 1 to C 12 alkyl or C 1 to C 12 alkoxy groups; or naphthyl, unsubstituted or substituted with one or more C 1 to C 12 alkyl or C 1 to C 12 alkoxy groups; and wherein Z and Z 1 are independently selected from the group consisting of structural formulae IV, V, VI, VII, and VIII:

 wherein

R 2 , R 3 , R 4 , R 5 , R 6 , R 7 , R 8 , and R 9 are independently selected from the group consisting of H, C 1 to C 12 alkyl, and C 1 to C 12 alkoxy;

X is O, S, or CH(R 10 );

R 10 is H or C 1 to C 12 alkyl;

 wherein

R 11 and R 12 are independently selected from the group consisting of H, C 1 to C 12 alkyl, and C 1 to C 12 alkoxy and CO 2 R 13 ,

R 13 is C 1 to C 12 alkyl, or C 6 to C 10 aryl unsubstituted or substituted with C 1 to C 4 alkyl;

Y is O, S, or CH(R 14 );

R 14 is H or C 1 to C 12 alkyl;

wherein R 15 is selected from the group consisting of H, C 1 to C 12 alkyl, and C 1 to C 12 alkoxy and CO 2 R 16 ,

R 16 is C 1 to C 12 alkyl, or C 6 to C 10 aryl, unsubstituted or substituted with C 1 to C 4 alkyl,

and wherein for structural formulae I through VII, the C 1 to C 12 alkyl, and C 1 to C 12 alkoxy groups may be straight chain or branched.

5. A process according to claim 1 , 2 , or 3 wherein the extraction is carried out above 40° C.

6. A process according to claim 3 wherein the Lewis base compound is selected from the group consisting of water, methanol, ethanol, isopropanol, ethylene glycol, phenol, cresol, or xylenol.

7. A process according to claim 3 , wherein the Lewis base compound is a monodentate triarylphosphite wherein the aryl groups are unsubstituted or substituted with alkyl groups having 1 to 12 carbon atoms, and wherein the aryl groups may be interconnected.

8. A process according to claim 3 wherein the Lewis base compound is selected from the group consisting of anhydrous ammonia, pyridine, alkylamine, dialkylamine, and trialkylamine wherein the alkyl groups have 1 to 12 carbon atoms.

9. A process according to claim 3 wherein the Lewis base compound is Amberlyst 21® resin.

10. A process according to claim 1 , 2 , or 3 wherein the extraction solvent is cyclohexane.

11. A process according to claim 1 , 2 , or 3 wherein said process is carried out in an extraction column or a mixer-settler.

12. A process according to claim 1 , 2 , or 3 wherein said process is used in a hydrocyanation process.