Use of a high shear mechanical device incorporated into a process for the production of chlorobenzene is capable of decreasing mass transfer limitations, thereby enhancing the chlorobenzene production process. A system for the production of chlorobenzene from benzene and chlorine, the system comprising a reactor and an external high shear device, the outlet of which is fluidly connected to the inlet of the reactor; the high shear device capable of providing an emulsion of chlorine gas bubbles within liquid benzene.