Pyrolysis of Brown Coal Microparticles under the Action of Nanosecond First-Harmonic Pulses from a Neodymium Laser

We report the results of a study of pyrolysis of pelletized coal grade 2B samples in argon under the action of laser pulses (1064 nm, 14 ns, 6 Hz, 0.2–0.5 J/cm²). The result of laser irradiation of coal samples is their ablation and the formation of H₂, CH₄, CO, CO₂, and C₂H₂ gaseous products. The dependence of the yield of the resulting gaseous products on the energy density of laser pulses is described within the framework of a model of a chain mechanism for the development of laser-initiated thermochemical reactions. The ablated mass of samples increases linearly with increasing radiation energy density when the threshold value is exceeded, H > 0.2 J/cm².