Phosgene

CAS RN: 75-44-5

Cleanup Methods

For liquid spills, cover with sodium bicarbonate or an equal mixture of soda ash and slaked lime. After mixing, spray water from an atomizer with great precaution. Transfer slowly into a large container of water. ... For gas spills, allow gas to flow into a mixed solution of caustic soda and slaked lime. If possible, keep in a hood until cylinder is emptied.
Environmental considerations: Air spill: Apply water spray or mist to knock down vapors.
Dilute aqueous phosgene wastes can best be handled through caustic scrubbing in packed columns or by scrubbing in towers with activated carbon and water. ... Phosgene should not be introduced into an incinerator. However, if a product containing, or capable of producing phosgene is entering an incinerator, then there must be an adequate scrubbing installation to remove phosgene and/or HCl from the issuing gases. These techniques must conform to all local and national regulations. Welding and disposal of tanks and equipment used to handle phosgene should take place only after all residual phosgene has been purged from these materials.
Environmental considerations: Water spill: Neutralize with agricultural lime (CaO), crushed limestone (CaCO3) or sodium bicarbonate (NaHCO3).
Environmental considerations: Land spill: Dig a pit, pond, lagoon, holding area to contain liquid or solid material. /SRP: If time permits, pits, ponds, lagoons, soak holes, or holding areas should be sealed with an impermeable flexible membrane liner./ Dike surface flow using soil, sand bags, foamed polyurethane, or foamed concrete. Neutralize with agricultural lime (CaO), crushed limestone (CaCO3), or sodium bicarbonate (NaHCO3). Dilute slowly with water.
Non-essential people should be kept away and the area isolated. People in the immediate vicinity should be moved to an area upwind until the gas has dispersed. Those involved in clean-up operations of large spills without fire should be provided with fully encapsulated protective clothing, and self-contained breathing apparatus. Fire-fighter's normal protective clothing will provide limited protection for short-term exposures only. For large spills a dyke should be made well ahead of liquid spill for later disposal. Water should not be allowed to enter the area inside the dyke or to enter any containers.
Liquid spills can be covered with sodium hydrogen carbonate or an equal mixture of soda ash and slake lime or crystallized urea. Water from an atomizer can then be added cautiously and the mixture transferred to a large volume of water. Gas spills can be mitigated by gaseous ammonia, aqueous ammonia or an ammonia steam curtain or sprays. There should be a holding area beneath any storage or handling installation that can contain a liquid spill. This should have an impermeable flexible membrane liner and must already contain lime, limestone, sodium hydrogen carbonate, urea or any other suitable neutralizing absorbent, sufficient to eliminate the spill.
Approach release from upwind. Releases may require isolation or evacuation. Stop or control the leak, if this can be done without undue risk. Water will increase evaporation of spilled material. Control runoff and isolate discharged material for proper disposal.
Find more information on this substance at: PubChem, PubMed