▎ 摘　　要

NOVELTY - Reducing residual pyrolytic carbon char into nano/submicron sized carbon black products from char of pyrolysis oil plant comprises subjecting the residual pyrolytic carbon char and acid solution (7) to leaching unit the horizontal or nozzle based hydrodynamic cavitation of an intensity sufficient to remove metallic and nonmetallic compound the impurities and to reduce the char size so that it easily gets dispersed into water for size reduction unit, an orifice based hydrodynamic cavitation reactor the size reduction unit, at constant pressure of cavitation reactor with chemical vapor less than 1, for constant time, produce a nano/submicron sized carbon black powder, the powder characterized as having a particle size distribution so that maximum portion of powder particles are less than 100 nm when dispersed in water. USE - The method is useful for reducing residual pyrolytic carbon char into nano/submicron sized carbon black products. ADVANTAGE - The method: provides precise smaller diameter particles of carbon black, carbon nanostructures and/or graphene or their derivatives; achieves maximum efficiency in less time with less energy consumption and increased range of applications of the obtained carbon black; and is easy to scale up in large commercial scale with low maintenance cost. DESCRIPTION OF DRAWING(S) - The figure shows a schematic representation of the horizontal type reactor of hydrodynamic cavitation method for processing waste pyrolytic carbon char feedstock. Raw carbon char (6) Acid solution (7) Horizontal reactor (8) Separation unit (10) Leachate solution (11)