How does perchlorethylene fit into the chloromethane production chain?

How does perchlorethylene fit into the chloromethane production chain?
Perchlorethylene is produced primarily via the carbon tetrachloride route, using CCl4 generated as a byproduct in chloromethane plants. This process not only yields perchlorethylene efficiently but also consumes carbon tetrachloride, a substance restricted under the Montreal Protocol due to its ozone-depleting properties. The reaction involves mixing carbon tetrachloride, chlorine, and ethylene or dichloroethane as a regulator, then passing the stream through a catalytic reactor at 400-600°C to produce perchlorethylene and hydrogen chloride as a byproduct. This integration makes chloromethane producers key suppliers, linking perchlorethylene availability to the operating rates of upstream methane chloride units, which are also constrained by environmental licensing for carbon tetrachloride production.