(185g) Development of a Holistic Approach to Design Solvent Extraction Systems for the Recycling of Used Lubricating Oils

Solvent extraction re-refining technique for used lubricating oils was found to be economically and environmentally attractive compared to other commercial technologies such as physical re-refining (distillation-based process) and chemical re-refining (acid-based process). Nevertheless, the development, and the optimization of a solvent extraction process for recovering base oil from used lubricating oil require extensive experimental investigations. The detailed design of the solvent extraction system normally targets efficient recovery of additives and sludge from the base oil while minimize oil losses in waste stream. A technique to utilize the solubility parameter difference between the solvent and additives in the prediction of sludge removal from used was developed by Elbashir, et al1 who identified this difference as the ?Anti-solvency Energy (ASE)?. This study reports the development of a holistic approach to the design of efficient solvent extraction systems for recycling of used oil. This technique is based on concepts of property-based clustering and property integration (e.g., Shelley and El-Halwagi2; El-Halwagi et al.3). A set of properties similar to those used in the calculation of the ASE are considered in this case, which are solubility, vapor pressure, and viscosity. To define the optimum operating region for either single solvent or composite solvents a mixing rule of each property is considered to determine dimensionless property operators. The summation of the dimensionless property is identified as the Augmented Property (AUP) and will be used to calculate the clusters, which are the ratio of the dimensionless operator and the AUP. A ternary diagram will then be developed to represent the intra- and inter-stream conservation, which is the key characteristic of property clusters. This work is unique because the properties of the solvents will be tracked in order to achieve optimum solvent extraction system, which is physically feasible and economically favored. An initial assessment of this method will be reported by correlating its outcome with experimental data generated from three organic solvents, namely 1-Butanol, 2-Propanol and Methyl Ethyl Ketone, at various extraction conditions.

1. Elbashir N. O.; S. M. Al-Zahrani; M. I Abdul Mutalib.; and A. E. Abasaeed (2002) "A Method of Predicting Effective Solvent Extraction Parameters for Recycling Used Oils." Chem. Eng. Proc. 41(9) 765-769. 2. El-Halwagi, M. M., I. M. Glasgow, M. R. Eden, and X. Qin, ?Property Integration: Componentless Design Techniques and Visualization Tools?, AIChE J., 50(8), 1854-1869 (2004) 3. Shelley, M. D. and M. M. El-Halwagi, 2000, "Componentless Design of Recovery and Allocation Systems: A Functionality-Based Clustering Approach", Comp. Chem. Eng., 24, 2081-2091