An apparatus for cooling a reactive mixture, comprising: a reactor configured to form the reactive mixture; a quench chamber comprising a frusto-conical body having a wide end, a narrow end, and a quench region formed between the wide and narrow end, wherein the quench chamber is configured to receive the reactive mixture from the plasma reactor through a reactive mixture inlet into the quench region, to receive a conditioning fluid through at least one fluid inlet, and to flow the conditioning fluid into the quench region, wherein the frusto-conical body is configured to produce a turbulent flow within the quench region with the flow of the conditioning fluid into the quench region, thereby promoting the quenching of the reactive mixture to form a cooled gas-particle mixture; and a suction generator configured to force the cooled gas-particle mixture out of the quench chamber.