In different environments and reaction conditions, liquefied gas contains sulfide on its own copper corrosion have varying degrees of impact, can be broadly summarized as the following three categories.

(1) elemental sulfur and copper sheet at room temperature and pressure can be direct contact reaction, in the copper sheet surface to generate black Cu2S precipitation, so that the copper sheet appears gray-black corrosion.

(2) H2S and copper at room temperature and pressure can also be reacted, so that the surface of the copper sheet to generate black Cu2S precipitation, gray-black corrosion.

(3) at room temperature and pressure, disulfide, mercaptan and other organic sulfides will not react with copper, so the corrosion is very weak; in the presence of oxygen or elemental sulfur conditions, disulfide and mercaptan will react slowly with copper, showing different degrees of corrosion. LPG usually contains some alkaline substances, such as NH3, NaOH and organic alkaline desulfurizing agent, etc., the copper sheet will be complexed with such alkaline substances under certain conditions, and then the copper sheet surface copper amine complexes, the generated complexes can further react with the copper sheet, so that the copper amine complexes eventually turn into black Cu2S precipitation, appearing gray-black corrosion.