| abstract |
Oxamide is produced in a high purity by a process comprising (A) melting a starting material comprising 70 to 100wt% of an oxalic acid diester of an aliphatic alcohol and 0 to 30wt% of the same aliphatic alcohol as mentioned above, (B) feed-mixing an ammonia-containing gas to the starting material melt, while stirring, to produce oxamide and the aliphatic alcohol (by-product), (C) continuing the ammonia-feed-mixing procedure while controlling a feed rate of ammonia to an extent such that a content of the aliphatic alcohol in the reaction mixture is maintained at a level of 3 to 45% by weight, to produce a wetted solid reaction product comprising the resultant oxamide and the aliphatic alcohol, and then (D) collecting the oxamide from the reaction product by evaporating away the aliphatic alcohol. |