3082.     SCHEUMANN, W. W., AND RESCORLA, A. R.  Aromatic Adsorption Index as Rapid Method for Approximating Catalyst Activity.  Oil Gas Jour., vol. 46, No. 28, 1947, pp. 231-232, 234; Petrol. Refiner, vol. 26, No. 12, 1947, pp. 815-817; Petrol. Processing, vol. 2, No. 12, 1947, pp. 946-947; Chem. Abs., vol. 42, 1948, p. 1726.

        This paper was presented at the 27^th annual American Petroleum Institute meeting in Chicago.  Of the various test methods for evaluating the activity of a catalyst, 2 have been used in the authors’ laboratory:  The Kellogg fluidized fixed-bed activity test based on a standardized laboratory cracking and the aromatic adsorption index based on surface area reactions.  This paper presents data showing the degree of correlation between the 2 methods on both natural and synthetic fluid catalysts.  A modified procedure, based upon the ability of a cracking catalyst selectively to adsorb aromatic hydrocarbons from a hydrocarbon mixture, is described in detail as better meeting personnel requirements and time limits for performing the tests.  The test, in brief, is carried out by first heat treating the catalyst sample at a temperature of 850° F.  A 3.5-gm. sample is then weighed into an adsorption vessel to which is added 5 ml. of a hydrocarbon mixture consisting of 30% toluene and 70% isooctane.  The adsorption vessel is shaken for 2 hr., after which the refractive index is determined on the supernatant liquid.  The aromatic adsorption index is the difference between the refractive index of the original hydrocarbon mixture and that of the hydrocarbon mixture, after contact with the catalyst multiplied by 10⁴.

        SCHIBSTED, H.  See abs. 1454.