Method for producing acrylamide
Provided is a method that is for producing acrylamide, continuously produces acrylamide from acrylonitrile using a biocatalyst, and is characterized in that a continuous reaction is started by means of introducing acrylamide into a reaction vessel and then causing acrylonitrile to contact a biocatalyst. The method for producing acrylamide has superior operability and a low cost, and is capable of continuously extracting an aqueous solution of acrylamide at a target concentration in a short period of time after starting the continuous reaction.
1. A method for producing acrylamide from acrylonitrile in the presence of a biocatalyst by a continuous reaction conducted in N number of reaction vessels that are connected in series, where N is a whole number of 2 or greater, the method comprising:
initiating the continuous reaction by introducing acrylamide and optionally the biocatalyst into a first reaction vessel positioned on the furthest upstream side of the continuous reaction, and thereafter bringing the acrylonitrile and, if no biocatalyst is present in said first reaction vessel, the biocatalyst into contact with the acrylamide and any biocatalyst in the first reaction vessel
wherein the biocatalyst converts the acrylonitrile into acrylamide in said N number of reaction vessels.
2. The method according to claim 1 , wherein acrylamide is present in a reaction vessel into which an acrylonitrile solution is directly supplied.
3. The method according to claim 2 , wherein N=2-10.
4. The method according to claim 1 , wherein said biocatalyst is selected from animal cells, plant cells, organelles, live bacterial cells, and dead bacterial cells.
5. The method according to claim 4 , wherein N=2-10.
6. The method according to claim 4 , wherein said biocatalyst is selected from animal cells, plant cells, live bacterial cells, and dead bacterial cells, and wherein the activity of the biocatalyst is 50˜500 U per 1 milligram of dry cells at a reaction temperature of 10° C. wherein a unit is the activity to produce 1 micromole/1 min of acrylamide from acrylonitrile.
7. The method according to claim 1 , wherein the acrylonitrile has a hydrocyanic acid concentration of 3 ppm or lower.
8. The method according to claim 1 , wherein N=2-10.
9. The method according to claim 1 , comprising initiating the continuous reaction by introducing acrylamide and the biocatalyst into the first reaction vessel positioned on the furthest upstream side of the continuous reaction and thereafter bringing the acrylonitrile into contact with the acrylamide and the biocatalyst in the first reaction vessel.
10. The method according to claim 9 , wherein N=2-10.
11. The method according to claim 9 , further comprising adding said biocatalyst and said acrylamide to each of said N reaction vessels prior to said initiating the continuous reaction.
12. The method according to claim 11 , wherein N=2-10.
13. The method according to claim 1 , comprising initiating the continuous reaction by introducing acrylamide and no biocatalyst into the first reaction vessel positioned on the furthest upstream side of the reaction and thereafter bringing the acrylonitrile and the biocatalyst into contact with the acrylamide in the first reaction vessel.
14. The method according to claim 13 , wherein N=2-10.