Pyrolysis of tetramethylurea

Abstract

The pyrolysis of tetramethylurea has been studied over the temperature range 450–600° in cells of varying surface area to volume ratio. The gaseous products were carbon monoxide, hydrogen, methane, ethane, ethylene (trace), ammonia, methylamine, dimethylamine, trimethylamine (trace), methyl cyanide, N-methylglycinonitrile, NN-dimethylglycinonitrile, hydrogen cyanide, water, methylene imine, N-methylmethylene imine and polymer. Hydrogen cyanide, methylene imine, and N-methylmethylene imine are formed in the pyrolysis zone and undergo addition reactions to form the observed products. A mechanism is suggested which accounts for these results. Good first-order kinetics were observed, with an activation energy of 46·5 ± 2 kcal/mol and an Arrhenius A factor of 10^9·5±^0·5 s^–1. The effect of adding varying pressures of sulphur hexafluoride to the pyrolysis system was studied.