2530
INDUSTRIAL AND ENGINEERING CHEMISTRY
Vol. 41, No. 11
34 0
CONMTIONSs 5.8 R V P LIGHT ALKYLATE 60 OF. REACTOR TEMPERATURE
320
--- __ - - - - - - -
100 % BUTYLENE ALKYLATE 77% PROPYLENE ALKYLATE 95-100% PROPYLENE ALKYLATE
120 100'
o
IO 20
30
40
50
60
70
eo so
loa
VOLUME PERCENT EVAPORATED
Figure 11. A.S.T.M. Distillations of Various Alkylates Produced
Figure 12, showing A.S.T.X. distillation tomperature against R.v.~.for the initial boiling point and 10 and 3001, points, can be utilized in conjunction with Figure 11 to calculate theA.S.T.DiI. distillation for various R.v.P. of 340 O F. end point light alkylate being produced from percentages of propylene in the olefin feed varying from 0 to 100%. The end point of the alkylate seemed to have little effect on the A.S.T.M. distil1at)ion as long aa the range fell within 325" to 350" I?. This is believed to be attributable almost entirrly to the small percentage of material heavier than 325' F. in the alkylate produced. HEAVYALKYLATE. In the alkylation reaction approximately 3 t o 6% of the total alkylate produced is undesirable for blending into aviation gasoline. This heavy alkylate has a boiling range of 340" initial to 540" F. end point. This material has a lower octane rating than light alkylate but is as good or better than the octane specifications required of motor gasoline. The material has been used for motor gasoline blending and for tractor fuel blending, Because of its high end point, although only a small quantity is above 430" F., it is not very desirable for motor gasoline blending unless further fractionation is carried out. BROMINE NUMBER.Sufficient bromine numbers, which indicate the degree of unsaturation, were determincd definitely to establish the fact that essentially no unsaturated components were present since the bromine numbers of the alkylate produced during normal operating conditions were less than 0.5. SUMMARY
I n summary, the following were noted: 1. As propylene in the o l e h feed increased: the octane number of the light alkylate produced decreased; R.v.p. of the CS-, free alkylate incieased: the temperature of the 30, 50, 70, and 90% A.B.T.M. volume evaporutrd points of the light alkylate produced decreascd; the percentage Ch and CBfractions produced in the reaction iricreaaed ; the isobutane to olefin combining ratio increased ; the total alkylate to olefin combining ratio increased; and acid consumption increased. 2. As the reartor-settler temperature increased the quality of alkylate derreased. 3. As the spent acid concentration increased from 89 to 957& no change in octaric quality was indicated. 4. As the external isobutane to olefin ratio increased, the octane rating increased, arid the alkylate to olefin ratio increased, within the range of the data.
Where raw materials of propylene and isobutane are available together with a cheap means of regenerating the spent acid, and
Figure 12.
A.S.T.M. Distillation Temperature against R.V.P.
there is a good demand for allrylate produced, a propylene alkylation procrss as described is economically sound. Tho differential costs between the raw materials and the sale value of the alkylate produced and the costs of the catalyst are the basic considerations for determining the feasibility of the alkylation of isobutane with propylene. ACKNOWLEDGMENT
The authors wish to express their appreciation to the Cities Service Refining Corporation for permission to publish this paper and to recognize the splendid cooperation of J. L. Sperry and N. N. Feller of the operating department. The authors gratefully acknowledge the indispensable assistance given by V. J. Yeakley and R. S. Freeman in preparing the graphs. LITERATURE CITED (1) Blair and Alden, XND. EXG.CHEM.,25, 559 (1933). (2) Gorin, M . H., Kuhn, C. S., Miles, C. B., Ibid., 38, 795 (L(J46). (3) Jong, Johan J., de, (to Shell Oil Company), U. S. Patent 2,381,041 (Aug. 7, 1945). (4) Kniel, Ludwig (to Eummus Company), dbid., 2,382,067 (Aug. 14, 1Y45).
(5) Linn, C . E., and Frosse, A. V., IND,ENQ.CHEM.,37, 924 (1945). (6) Skinner, E. M., Trans. Am. d m t . Chem. Engrs., 41, 647 (1945). RZCEXVED December 23, 1948.
Effect of Oil on Plastic Properties of Petroleum Waxes I n the discussion of their flexibility test procedure [Nelson, 41, 2231 (1949)], the authors give credit to the Daugherty Refinery laboratory for their method of specimen preparation. They state, however, that this method for determining the flexibility of microcrystallino waxes has not yet been discussed in the literature. This stat+ ment was correct when the paper was written in 1947. However, in the meantime the method and testing apparatus havcl been fully described in a paper entitled "Flexibility of Microcrystalline Wax" [Kinsel, A,, and Schindler, H., Paper Trade J , 126, 58-60 (March 25, 1948)l.
w.L., and Stewart, L. D., IND. ENG. &EM.,
H. SCHINDLBR L. SQNNEBORNSONE,INC. DAUQSERTY REPINERY PETROIJA, PA.
