1. Used in sodium formate, as a reducing agent in the metallurgical industry.
CO+NaOH==high temperature and high pressure==HCOONa
2. Industrial reduction of iron oxide (preparation of iron)
3. Used as a gaseous fuel, such as water gas (a mixture of gases such as carbon monoxide and hydrogen).
4. Used for preservation, mainly for fishing. In particular, Southeast Asia and Vietnam people like to use CO for fisheries preservation.
