摘要：Waste lubricant oil can be regenerated by flocculation and adsorption to get rid of impurities. In this work, the performance of flocculants (chitosan, sodium carbonate and sodium silicate) and sorbents (carclazyte and silica gel) were evaluated experimentally. The results showed that the combination of chitosan and sodium carbonate had beat results in removal of acid value and mechanical impurities. Silica gel contacting adsorption had the best colour removal. Thermal precipitation (80°C, 24h) was adopted as primary step before flocculation to wipe off heavier particulate matter. The best ratio of chitosan, sodium carbonate and silica gel was 1:1:1, and the best dosage of chitosan was 2% compared to oil. After the re-refining process, viscosity decreased from 186.34 (mm2/s, 40°C) to 155.21 (mm2/s, 40°C), the acid value from 0.26 (mg KOH/g) to 0.06 (mg KOH/g), mechanical impurities content from 3.62% to 1.41%, water content from 0.45% to 0.06%, and light absorbance from 4.31 to 1.17.
