Low pressure process for manufacture of 3-dimethylaminopropylamine (DMAPA)
AssigneeSolutia Inc.
InventorsGregory J. Ward, Bryan C. Blanchard
Life of this patent
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Abstract
An improved process for the production of 3-dimethylaminopropylamine in high (>99%) purity from N,N-dimethylaminopropionitrile utilizing a low pressure hydrogenation process is described. The basic process comprises contacting the nitrile with hydrogen at low pressure in the presence of a sponge nickel catalyst under conditions sufficient to effect the conversion of the nitrile to the primary amine product. The improvement in the process resides in a combination of carrying out the hydrogenation process at low pressures and temperatures in the presence of a catalytic amount of caustic base in order to give an improved selectivity of greater than 99.60% of DMAPN to DMAPA.
Claims17
A process for the production of N,N-dimethylaminopropylamine from N,N-dimethylaminopropionitrile by low pressure hydrogenation comprising:
- feeding hydrogen and N,N-dimethylaminopropionitrile into a low-pressure reactor containing a sponge nickel catalyst, at least one Group IA alkali metal hydroxide, and water to form a reaction medium;
- heating the reaction medium to a temperature of about 70° C. to about 100° C.;
- pressurizing the reactor to a pressure of about 45 psig to about 150 psig;
- mixing the reaction medium to provide a uniform concentration of the nitrile;
- and
- hydrogenating the nitrile to form N,N-dimethylaminopropylamine,
- wherein the process has a selectivity of N,N-dimethylaminopropionitrile to N,N-dimethylaminopropylamine of greater than about 99.60%.
A process for the production of N,N-dimethylaminopropylamine from N,N-dimethylaminopropionitrile by low pressure hydrogenation comprising:
- feeding hydrogen and N,N-dimethylaminopropionitrile into a low-pressure reactor containing a sponge nickel catalyst, at least one Group IA alkali metal hydroxide, and water to form a reaction medium;
- heating the reaction medium to a temperature of about 70° C. to about 100° C.;
- pressurizing the reactor to a pressure of about 45 psig to about 150 psig;
- mixing the reaction medium to provide a uniform concentration of the nitrile;
- and
- hydrogenating the nitrile to form N,N-dimethylaminopropylamine,
- wherein the process has a selectivity of N,N-dimethylaminopropionitrile to N,N-dimethylaminopropylamine of greater than about 99.90% and a yield of N,N-dimethylaminopropylamine of greater than 99.0%.
A process for the production of N,N-dimethylaminopropylamine from N,N-dimethylaminoproprionitrile by low pressure hydrogenation comprising:
- feeding hydrogen and N,N-dimethylaminopropionitrile into a low-pressure reactor consisting of a sponge nickel catalyst, potassium hydroxide, and water to form a reaction medium;
- heating the reaction medium to about 90° C.;
- pressurizing the reactor to about 100 psig;
- mixing the reaction medium to provide a uniform concentration of the nitrile;
- and
- hydrogenating the nitrile to form N,N-dimethylaminopropylamine,
- wherein the process has a selectivity of N,N-dimethylaminopropionitrile to N,N-dimethylaminopropylamine of greater than 99.70%.
Dependencies are inferred from the claim text.