| 摘要 |
1285578 Ion exchange; purifying water ROHM & HAAS CO 3 Sept 1969 [3 Sept 1968] 43547/69 Heading B1J [Also in Division C1] Ammonia values and hydrogen sulphide values are removed from a liquid, for example sour or foul waste water produced in petroleum refining, by a process which comprises passing the liquid through a bed of weak carboxylic acid cation exchange resin, whereby ammonium ions in the liquid are exchanged for hydrogen ions and free hydrogen sulphide is liberated into and retained in the effluent liquid from the bed, and thereafter removing hydrogen sulphide from the effluent liquid, for example by stripping under reduced pressure and optionally at elevated temperature, for example 30-35‹C. After removal therefrom of hydrogen sulphide, the liquid either may be clarified and freed from phenolic contaminants by contact with weakly basic anion exchange resin or may be clarified and neutralized by treatment with a flocculant and alkaline material, for example lime in the form of an aqueous suspension, or may be clarified by treatment with bentonite and a proprietary synthetic cationic polyelectrolyte flocculant, as disclosed in United States Specification 3300406. The cation exchange resin may be regenerated with sulphur dioxide or sulphuric acid; the anion exchange resin may be regenerated with sodium hydroxide, ammonium hydroxide, sodium carbonate, lime or the effluent waste obtained from regenerating the cation exchange resin with sulphuric acid. |
