Studies on Calcium Cyanamide. III. Storage and Mixing with Superphosphate

Abstract

1. On storage under good farm conditions Calcium Cyanamide gained steadily in weight, the increase reaching about 10 per cent. after 27 months. The percentage of nitrogen decreased at a practically equivalent rate, so that there was little change in total nitrogen. The form of the nitrogen remained practically unchanged for the first 6 months; by 12 months there was a slight reduction in cyanamide nitrogen and a slight production of dicyanodiamide—less than 1 per cent. of the total nitrogen. 2. In a farm mixture of Calcium Cyanamide and superphosphate (1:3) cooled by spreading in a thin layer after mixing, 16 per cent, of the nitrogen was converted to dicyanodiamide in the fresh mixture and this increased to 25 per cent, after 1 month's storage. More dicyanodiamide was produced in a series of laboratory mixtures of Calcium Cyanamide and superphosphate, in which heating was allowed to take place. Dicyanodiamide production varied regularly with the composition of the mixtures, rising to a maximum of 50 per cent. of the total nitrogen in the mixture containing 20 per cent. of Calcium Cyanamide, and falling to below 20 per cent. of the nitrogen in the 50 per cent. mixture.