1922 Krase Synthesis of Urea from Ammonia and Carbon Dioxide
The paper describes the development of a process for the synthesis of urea from ammonia and carbon dioxide. The process consists in the preparation of ammonium carbamate, autoclaving to cause partial conversion to urea, distillation of the resulting sludge to separate the urea from the unconverted ammonia and carbon dioxide, and condensation of the distillate with additional gas to form a new charge. A small-scale experimental plant for testing the process was built and operated. A discussion of the conversion reaction from a theoretical standpoint is given. Cost considerations lead to the conclusion that the cost of urea by this process would be largely dependent on the cost of ammonia. It seems possible that the process might have commercial significance for the production of urea for fertilizer purposes, and in any case the process is of interest for the production of urea for its present uses in the arts.