| 摘要 |
PURPOSE:To obtain a reclaimed oil having a low ash content by dispersing a specific phosphoric (phosphorous) acid compound in a used lubricating oil to contact them under sufficient reaction conditions, adding activated clay, etc., and filtering the dispersion. CONSTITUTION:A phosphoric acid compound and/or a phosphorous acid compound both represented by the formula (wherein R1 and R2 may be the same or different and each is a 6-18C aryl or alkylaryl, and R3 is H or OH) is dissolved in a used lubricating oil in an amount of 0.8-6wt.%. The solution is heated at 60 deg.C or higher, preferably 80-160 deg.C, for 10min to 24hr to contact the acid compound with the sludge, soot, etc. The resulting precipitate is filtered off. At least one adsorbent selected from activated clay, diatomaceous earth, and active carbon is added to the resulting oil in an amount of 1-20wt.% based on the oil. The mixture is heated at 40-160 deg.C for 10min to 24hr. The precipitated or suspended matter is removed with a suitable filter selected from, e.g. 50- to 400-mesh screens. It is desirable that the treated oil be hydrogenated. The ash content of the reclaimed oil is about 0.2% or lower. |
