DFT study on the sulfur migration during benzenethiol pyrolysis in coal

The migration of sulfur resulting in the formation of CS, H2S and thiophene during benzenethiol pyrolysis has been investigated using the density functional theory method with PW91 functional and DND basis set. The lowest energy path is that H of the thiol group transfers to the ipso C and S radical is eliminated by beta scission reaction, and then the S radical combines with H radical formed during coal pyrolysis and eventually results in the formation of H2S. The formation of H2S via benzenthiol pyrolysis is easier than via thiophene by comparing with the kinetic data.