A laboratory study is made of synthetic mixtures of carbon dioxide, ammonia, and urea, corresponding to possible compositions in the melts obtained in synthesizing urea. The method of preparing the mixtures water is described and the apparatus used is illustrated.
Determinations are made of the liquid areas of urea- ammonia-carbon dioxide system obtained in the synthesis of urea, and isotherms constructed for the liquid condition with compositions indicated on a ternary diagram. The data obtained indicate the temperatures that must be maintained in the outflow material of the autoclave and the minimum temperature required Table I. for the still in the recovery of ammonia from the melt.

1931 Davis Ind Eng Chem Liquid Area of Urea-Ammonia-Carbon Dioxide System.pdf