ANALYTICAL EDITION
356
rarely be dissolved in the parent gasoline, whether deposited in laboratory tests or under the conditions existing in an engine. It has been pointed out above that a certain amount of the gum-forming material present in the gasoline can be distilled even in a relatively slow process of distillation. The amount of residual gum obtained on evaporation should be expected to be greater when dilution of the gasoline is made with an equal volume of liquid of low boiling point than when the diluent is of high boiling point. I n the former case the amount of gum ordinarily deposited from gasolines containing gum-forming constituents should therefore be less than onehalf the value obtained for the undiluted sample. TABLEVI. GUM CONTENTOF 50 PER CENT MIXTURESOF GUM-CONTAININQ GASOLINES WITH VARIOUSGUM-FREE DILUENTS
Vol. 4, No. 4
(9) Littlejohn, W., Thomas, W. H., and Thompson, H. B., J. Inst. Petroleum Tech., 16, 684 (1930). (10) Mardles, E. W. J., and Moss, H., Ibid., 15, 657 (1929). (11) Molitor, J. C., J. Soc. Automotive Eng., 28, 472 (1931); unpublished paper presented before Petroleum Division, American Chemical Society, 81st Meeting, Indianapolis, March, 1931. (12) Norris, W. S., and Thole, F. B., J . Inst. Petroleum Tech., 15, 677 (1929). (13) Smith, N. A. C., and Cooke, M. B., Bur. Mines, Repts. Investigations 2394 (1922). (14) Voorhees, V., and Eisinger, J. Am. Petroleum Inst. Bull., 10, See. 11,169 (1929); J.Soc. AutomotiveEng.,24,584 (1929). (15) Wagner, C. R., and Hyman, J., Am. Petroleum Inst. Bull., 11, See. 111, 118 (1930). (16) Wilson, R. E., J . SOC.Automotive Ena.. 27. 38 (1930). (17) Yule, J. A. C:, and Wilson, C. P., 5.;IND. E&G. CHEM.,23, 1254 (1931).
o.,
RECEIYED May 25, 1932.
(High-temperature air jet method)" (1) GUM (2) G U M GASOLINE DILUENT(B.P..
H H H H
H
O
C.)
Mineral Seal oil (280-320) X lene 140) &losolve acetate" (140-180) +Heptane (98) Commercial cracked gasoline (I. B. P.30,E.P.200) Petroleum ether Straight-run gasoline (I. B. P. 30 E P. 175) Stra&hd-run gasoline (I. B. P.
FROM 50 FROM 50 ML. O F UN- ML. O F DILUTED DILUTEDRATIOOF SAMPLB SAMPLE(2) TO (1'1
Ma. 38.1 38.1 38.1 38.1
Ma. 22.8 23.4 17.3 15.2
59 61 45 40
38.1 38.1
15.1 15.0
39.6 39.4 38.6
I"
38.1
14.7
30, E. P. 175)
8.4
3.1
37
30 E P.175)
18.3
7.2
39
25.4
9.6
38
41.7
18.9
41
Straight-run gasoline (I. B. P. Straehi-run gasoline (I. R. P.
E.P.175) Strafght-run gasoline (I. B. P. 30,E.P. 175) 30
Straight-run gasoline (1. B. P. 30 E. P. 175) Stra&ht-run gasoline (I. B. P. 30. E.P 175)
An Efficient Absorption Tube
o/,
5.0
2.5
50
15.5
7.1
46
E. F. DEGERING, Purdue University, Lafayette, Ind.
T
HE accompanying figure shows a combination of the Folin and Meyer absorption tubes. This type of tube has proved much more efficient as a gas scrubber than either the Folin or the Meyer tubes, and is especially useful as absorption apparatus where a rather rapid flow of a gas is being scrubbed by suitable liquid absorbents.
0 All gums were of resinous type, exce t in case of gasoline Q where gum was of oily type, and in oase of gaso!&e R where residue. was partly oily, partly resinous, and partly composed of water-soluble sohd.
I n Table VI are given the results of a number of experiments on 50 per cent mixtures of gummy gasolines with various diluents, and in Figure 4 are shown the gum-content values obtained for different concentrations of a gummy gasoline with a gum-free straight-run gasoline. Gum determinations were made on all liquids used as diluents in the pure state, and of these only Mineral Seal oil left a residue of gum; in this case the value given in Table VI has been corrected. The results point to the presence of gum-forming constituents in most of the gummy gasolines used. Only in the case of gasoline Q could the deposited gum be completely redissolved in the original gasoline. It is also evident, from the results with gasoline H, that when the diluent is of high boiling point the gum-content value found approaches onehalf the value for the undiluted sample more nearly than is the case when the diluent is of low boiling point. I n certain cases the value found is greater than one-half the value for the undiluted sample, and in the case of Mineral Seal oil this may be ascribed to a prolongation of the evaporation period, thereby enabling the gum-forming material to play its role more effectively than during the evaporation of the undiluted gasoline. LITERATURE CITED
i
The dimensions given in the drawing are for a tube holding about 150 cc. of the absorbing liquid or solution. Tubes of proportionate size would satisfy the requirements for smaller or larger amounts of the absorbent. If made of Pyrex glass and properly handled, tubes of this type are quite durable and very satisfactory in analytical procedures. These tubes were designed and made as a means of affording more accurate determination of carbon dioxide by the wet method where a rapid flow of the gases was required.
Boyd, T. A., J. SOC.Automotive Eng., 18, 641 (1926). Bridgeman, 0. C., and Aldrioh, E. W., Ibid., 28, 191 (1931). Brookes, B. T., IND.ENG. CHEM., 18, 1198 (1926). Cooke, M. B., Bur. Mines, Repts. Investigations 2686 (1925). Fisoher, H . G. M., announced by Beoker, A. E., J. Soc. Automotive Eng., 28, 473 (1931). (6) Hall, W. A., J . Inst. Petroleum Tech., 1, 147 (1915). (7) Herthel, E. C., and Apgar, F. A., Am. Petroleum Inst. Bull., 11, See. 111, 124 (1930). May 5, 1932. Tube designed and made in connection with a (8) Hunn, E. B.;Fischer, H. G. M., and Blaokwood, A. J., J. SOC. RECBIVED researoh problem at the University of Nebraska. Automotive Eng., 26, 31 (1930). (1) (2) (3) (4) (5)
