China produced ~15 million tons of PVC in 2013, 75 % from coal (Ca-carbide derived acetylene, addition of HCl with a HgCl2 catalyst). DICP developed a process based on silicon carbide doped with nitrogen which showed excellent hydrochlorination characteristics. Conversion was 80 %, and selectivity 98 % related to vinyl chloride.
CAS news release, April 24, 2014