Calcium hydroxide is widely used in petrochemical industry. It can be used as a catalyst and neutralizer to catalyze and regulate chemical reactions. For example, in the oil refining process, calcium hydroxide can be used to neutralize acidic catalysts, thereby increasing the efficiency and yield of the oil refining. Petroleum industry added in lubricating oil, can prevent coking, sludge deposition, neutralization and anti-corrosion, general production of lubricating oil manufacturers need to use, but the amount is small.