ESTIMATION OF CRITICAL PROPERTIES OF CARBAMIC ACID DERIVATIVES FOR MODELING THE PHOSGENE-FREE SYNTHESIS OF ISOCYANATES

The development of phosgene-free synthesis technologies for isocyanates based on the thermal decomposition of N-substituted carbamic acids represents a promising direction for ensuring the import-independent advancement of the domestic chemical industry. However, the limited availability of experimental data on the thermodynamic properties of carbamates significantly complicates the modeling of such processes.This study presents a validation of group contribution estimation methods (Lydersen, Ambrose, Joback, and Gani) based on the comparison of experimental and calculated values of boiling points and critical parameters of alkylurethanes. The analysis identified the most accurate methods for each parameter.Based on the selected models, thermodynamic properties were estimated for carbamates lacking experimental data in open sources. These results can be used for further mathematical modeling of isocyanate synthesis processes.