METHOD OF RECOVERY OF MERCURY FROM SPENT CATALYST FOR SYNTHESIS OF VINYLCHLORIDE

摘要

The active carbon is burnt with a controlled amt. of air of O2 so the combustion gases contain, in addn. to metallic Hg vapour, 0.5-5 vol. % O2 and 2-15 vol. % CO; the gases travel through a condensation zone for sepg. the Hg with water and are then washed with alkali before release to the atmos. The combustion gases pref. contain (vol. %) 1-3 O2, 4-10 CO, and the alkali is pref. caustic soda. Process is esp. for recovery of Hg from catalyst used in mfg. vinyl chloride from acetylene and HCl. The Hg obtd. is free from phosphorous cpds. and the P2O5 and SO2 are effectively removed.