The petroleum industry refers to the chemical industry that uses oil and natural gas as raw materials. The range is very wide and there are many products. The crude oil is subjected to cracking, reforming and separation to provide basic raw materials such as ethylene, propylene, butene, butadiene, benzene, toluene, xylene, naphthalene. From these basic raw materials, various basic organic raw materials such as methanol, formaldehyde, ethanol, acetaldehyde, acetic acid, isopropanol, acetone, phenol, etc. can be obtained.