Kinetics and mechanism of the thermal decomposition of methyl isocyanate

The kinetics of gas‐phase decomposition of methyl isocyanate have been investigated in the range of 427–548°C. Two decomposition routes are followed; the predominant one is a radical‐chain process giving CO, H 2 , and HCN as major products, which has an order of 1.5 and an Arrhenius equation given by log k (L 1/2 /mol 1/2 ·s) = (13.12 ± 0.06) − (56,450 ± 1670) cal/mol/2.303 RT . The minor route is the bimolecular formation of N , N ′‐dimethylcarbodiimide and CO 2 , which from the low activation parameters E a = 31.6 kcal, A = 10 5.30 L 1/2 /mol 1/2 ·s, and the reaction order of 1.57 appears to be heterogeneous.