Environmentally Friendly Recovery and Characterization of Oil from Used Engine Lubricants

Abstract

The present paper demonstrates the review of some acid processes as well as development of some new solvent processes for reclamation of used lubricating oils. The conventional processes are found to be of low yield (; 50%), laborious, time consuming and environmentally hazardous, because of residual acidic sludge. Based on the findings, a new modified Aluminium sulphate-sodium silicate-acid-base method employing a small quantity of acid and giving a high yield (; 60%) is proposed. Further, to avoid use of acid, new regeneration processes based on solvent extraction were investigated. They are termed CCl 4 -alcohol method, Dodecane-alcohol method and Toluene-alcohol method. These processes are not only cost effective in terms of complete solvent recovery, but are rapid, less time consuming, more environmentally friendly and gave a high yield (70-75%). The virgin lubricants (Castrol GTX and Rimula-C) as well as oils recovered by different methods were also characterized physicochemically to determine kinematic viscosity, density, refractive index, carbon distribution, wear scar diameter, % Conradson carbon residue, % ash, % chloride, pour point, etc. Results obtained show that many of the physico-chemical properties of the recovered oils are in good agreement with those of virgin oils. The n.d.M analysis was also performed which shows that virgin oils have 73 ± 3% paraffinic carbon, 26 ± 3% naphthenic carbon and about 1% aromatic carbon. The recovered oils also showed nearly the same chemical composition. The UV-Visible spectra of the recovered oils are all similar to those of virgin lubricants. The results suggest that the oils recovered by solvent treatments, particularly Dodecan-alcohol and Toluene-alcohol methods, may serve for lubrication purposes and can be rendered as excellent as virgin lubricants with the addition of certain additives. The proposed methods may be considered as alternative cost effective green techniques for acid reclamation processes and being the motivation of the present investigation.

Comparing the Properties of Virgin & Aged Bitumen by the addition of Rejuvenators

“…The quality and effectiveness of rejuvenators can be compared with reference values of the virgin binders by comparing the standard tests such as softening point and penetration of the rejuvenator-aged bitumen [11]. In Pakistan, a large number of used engine oils from various sources are disposed into the rivers, lakes and Arabian Sea which not only contaminate water but are also harmful to marine life [12]. Approximately, one gallon of waste engine oil would pollute one million gallons of water [10].…”

Treatment of Waste Lubricating Oil by Chemical and Adsorption Process Using Butanol and Kaolin

“…Some of the processing that has been done, among others, used oil processing using various absorbent [6], and used oil recycling processes with new washing agents such as acetic acid belonging to Hamawand et al [7]. According to Udonne, et al [1] on the comparison of four recycled lubricant methods used: clay-processing, clay-distillation, acid treatment and charcoal processing methods or active clay.…”

Compound changes in re-refined used lubricating oils using fabricated Packed-bed reactor

“…10 Although the oil resulting from this process was akin to that produced by the acid-clay method, it is not cost effective as expensive solvents and vacuum distillation set-ups are essential to carry out the technique. 11,12 In the report of Rincon et al, 13 propane was used as a solvent. Propane can dissolve paraffinic or waxy material and partially dissolve oxygenated material.…”