A method of recycling captured agglomerated soot captured by and collected from a diesel emission control after-treatment (DECAT) system, the method comprising collecting captured agglomerated diesel soot (CADS) as a feedstock, loading the CADS into a controlled thermochemical conversion (TCC) process reactor, employing time-phased heat and pressure in the controlled TCC process reactor until the CADS sufficiently decompose to reclaim solids, liquid fuels and gases, piping pyrolysis oils (tars) and vapors produced in the controlled TCC process reactor to chambers, cooling and condensing the pyrolysis oils and vapors into a liquid form, and recirculating a pyrolysis gas produced in the controlled TCC process reactor for use as a source of heat and power.