Study On The Corrosion Reasons Of Lubricating Oil Ketone Benzene Dewaxing Devices

Corrosion exists in the construction of each domain of the economicand the national defense, the corrosion of oil chemical equipment isparticular outstanding. Because the raw material composition of thepetroleum has been changed, and the process of production is extremelycomplex, accidents happen, which caused the huge economic loss, evendisastrous accident.Lubricating oil is a kind of very important oil products. To be normaloperated, almost every moving parts of the machine need it. Thelubricating oil is made of the base oil and additives. The quality of baseoil is the most important influencing factor of the lubricating oil quality.During the complex production process, corrosion can’t be avoided. Atpresent, the production of the base oil is still used old three sets oftechnology, which are solvent refining, solvent dewaxing and clay addedrefining, etc.In order to find out the material caused serious corrosion in theoperation of lubricating oil refining device, the study and analysis wereexecuted from ketone benzene dewaxing devices. And thencomprehensively research was taken on the point of origin which wastotally damaged by corrosion, so that the mechanism of corrosionfunction was known. After simulative experiment, the conclusion ofcorrosion was validated.This study was from water sample, the situation about the water’scorrosion was known. Afterwards, HPLC and LC-MS techniques wereused; corrosion was caused by the naphthenic acid and furoic acid and soon. And then, the active component was extracted with sodiumhydroxide–ethanol solution from the raw oil, after that corrosionexperiment was proceeded, and infrared spectrum was used to detect thechange of properties between raw oil with the active component before and after extracted and the composition of the active component. Theactive component is demonstrated the main material causing the seriouscorrosion only at high temperature，and the acid was demonstrated mainlythe naphthenic acid. After furfural refining, furfural was changed tofuroic acid, which formed azeotrope with water, and into theketone-benzene dewaxing device. After ketone-benzene dewaxing unit,evaporation, recover solvent, in the process, acid material move intowater, the circulation acidity material continuously accumulation, causedserious equipment corrosion.