758. DUPAS, M. R. [Lubricant Synthesis.] Bull. assoc. franc. techniciens petrole, No. 69, 1948, pp. 1-16; Jour. Inst. Petrol., vol. 34, 1948, p. 265 A; Chem. Abs., vol. 43, 1949, p. 1952.

758. DUPAS, M. R. [Lubricant Synthesis.] Bull. Assoc. Franc. Techniciens Petrole, No. 69, 1948, pp. 1-16; Jour. Inst. Petrol., vol. 34, 1948, p. 265 A; Chem. Abs., vol. 43, 1949, p. 1952.

After a brief review of the chief methods for lubricating-oil synthesis, describes (with flow sheet) the process used at the Standard-Kuhlmann plant at Estaque. Lubricating oil is produced by a Friedel-Crafts condensation of benzene with dichlorethane and a Fischer-Tropsch gas oil (180°-320°) chlorinated to a Cl content of 22-24%. Production is effected continuously in 3 steel vessels; in the 1^st vessel (at 80°) benzene, dichlorethane, and Al powder are mixed. The chlorinated gas oil is added in the 2d stage (at 100°), and the reaction is concluded in the 3d vessel (at 120°). Flow through the plant takes 6 hr. The supernatant oil is separated from the AlCl₃ residue, neutralized with Na₂CO₃ solution, and the excess benzene is removed by distillation. Following a clay treatment to eliminate traces of AlCl₃ the product is vacuum distilled yielding 2 side streams (transformer and light engine oils) and a residual bright stock. Gas oil is removed overhead and recycled. A further quantity of secondary oil, together with benzene and gas oil, is recovered by hydrolysis of the AlCl₃ residue. The yields (as % on the hydrocarbon charge) are: primary oil, 45%; secondary oil, 10%; recycle, 27%; and loss, 18%. The viscous oils (35-330 cs. at 50°) obtained have high density (0.942-0.950) and good viscosity index.

DUPONT, G. See abs. 1260.