Study on new decolorization technology of waste lubricating oil

Abstract

The decolorization and regeneration of waste lubricating oil is an important measure to prevent pollution and protect the environment. In view of the serious pollution of the traditional decolorization process of waste lubricating oil, according to the reasons for the color of waste lubricating oil, the decolorization effect of waste lubricating oil under different experimental conditions was investigated by the combination of chemical method and adsorption method, taking the total decolorization rate and total oil yield rate as evaluation indexes. The experimental results showed that: in 150 g waste lubricating oil, the mass fraction of 22% ammonium chloride solution was added, the upper layer was taken after centrifugation, and the decolorization rate was up to 11.74%. 30 ml of 15% sodium hydroxide solution was added into the obtained upper layer solution, and the upper layer was centrifuged and the total decolorization rate was 19.19%. Then attapulgite clay was used to adsorb and depressurize the obtained upper solution, through single factor experiment, the better conditions of adsorption decompression filtration were obtained as follows: attapulgite clay content was 15% of the mass fraction of waste lubricating oil, decolorization temperature was 50°C, pressure of 65.6-66.7 kPa was reduced for 5 minutes. After the above decolorization steps, the total decolorization rate and total oil yield of waste lubricating oil are 84.31% and 79.32%, respectively.