Carbon monoxide is a colorless, odorless, flammable toxic gas.
Liquid carbon monoxide is a cryogenic liquid, which exists at temperature of -192oC and atmospheric pressure. It becomes a flammable vapor upon addition of heat and has a threshold limit value (TLV) of 50 ppm.
In metallurgy, it is used to recover high purity nickel from crude ore in the Mond process and for special steels and reducing oxides. It is also used to obtain powdered metal of high purity, such as zinc white pigments, and to form certain metal catalyst applied in synthesizing hydrocarbon or organic or oxygenating compounds