Chromatographic Fractionation to Total Crude Shale Oil - Analytical

May 1, 2002 - Karr, W. D. Weatherford, T. R. Kendrick, and R. G. Capell. Anal. Chem. , 1954 ... Note: In lieu of an abstract, this is the article's fi...
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1842

V O L U M E 2 6 , N O . 11, N O V E M B E R 1 9 5 4 Table I.

Analysis of Approximately Equimolar Mixtures of Three Halides

h1ixture No. 1 2 3 4

iYaC1, Mmoles. Taken Found 2.223 2.241 2.480 2.472 2.164 2.166 2.393 2.387

KBr, Mmoles. Taken Found 2.184 2.177 2.205 2.207 2.478 2.473 2.471 2.462

XI, Mmoles. Taken Found 1.831 1.835 1.950 1.946 1.984 1.981 2.066 2.067

A or 70 ml. for column B, was also collected in a graduate. The third fraction of 260 or 330 ml. was similarly collected. Finally, 100 ml. of 0.50114 sodium nitrate was passed through the column to prepare it for the next separation. This effluent was rejected. As indicated in Figure 1, the three fractions of effluent contain the isolated chloride, bromide, and iodide, respectively. These fractions were titrated with the same techniques as used in the standardizations. RESULTS

of effluent was collected in a graduated cylinder. Then the 2.OM Podium nitrate was passed through the column a t the same rate. The change in eluant is indicated by the dotted line in Figure 1. The reservoirs of eluant solutions were Mariotte flasks ( d ) , so that constant heads and hence constant flow rates could be easily maintained. The second fraction of effluent, 55 ml. for column

Table 11. Determination of One Halide in the Presence of Large Amounts of the Other Halides Series A = , NaC1, Micromoles Taken Found

Series Ba, KBr, Micromoles Taken Found

Seriea CC, K I , Micromoles Taken Found

..

9 9 5 4 KBr a n d KI, 2.3 millimoles of each. NsCl and KI, 2.3 millimoles of each. NaC1 a n d KBr, 2.3 millimoles of each. 10

C

LITERATURE CITED

(1) Kolthoff, I. M., and Stenger, 5’. A , , “Volumetric Analysis,” Voi. 2 , p. 252, New York, Interscience Publishers, 1947. (2) Kiederl, J. B., and Niederl, V., “Organic Quantitative Microanalysis,” 2nd ed., p. 114, X e w York, John Wiley & Sons, 1942 (3) Rieman, W., and Lindenbaum, S.,ANAL.CHEM.,24, 1199 (1952).

10

a

Four mixtures of approiimately equivalent, weighed amounts of the three halides were analyzed by this procedure. The results, Table I, indicate that the average error in the determination of any one halide is k O . O 9 % of the total halide. Three series of determinations were run in which the samples consisted of 2.3 millimoles each of two halides, while the amount of the third halide was decreased throughout the series. These results are listed in Table 11. The average error, bithout regard to sign, in the determination of the trace halide, was 0.0207, of the total halide content of the mixture.

RECEIVED for review October 6, 1953. rlccei)ted January 26, 1954. Taken from a thesis submitted by R. C. DeGeiso t o the faculty of Rutgers University in partial fulfillment of the rerluireinents for the degree of bachelor of science with honors.

Chromatographic Fractionation of Total Crude Shale Oil CLARENCE KARR,

JR.,

W. D. W E A T H E R F O R D , JR., T. R. KENDRICK Ill’, and R. G. C A P E L L

Mellon Institute, Pittsburgh, Pa.

Fractionation of total crude shale oil by elution chromatography on activated alumina or activated bauxite gives 40 to 45 weight %of a colorless, color-stable, pleasant-smelling oil which is free of nitrogen compounds and substantially reduced in sulfur content. About 4 weight % can be recovered as a yellow, color-stable, pleasant-smelling oil which is free of nitrogen compounds, and essentially all the remaining constituents can be recovered from the adsorbent as a brown-black semisolid enriched in nitrogen and sulfur compounds.

S

HALE oil production has existed on a commercial scale for

some time in certain countries that have insufficient or depleted petroleum reserves. Production of oil from shale is contemplated for the United States, when the increasing demand for fuels and petrochemicals rises appreciably above the petroleum supply. The oil shales in the known reserves of this country could supply a t least 224 billion barrels of shale oil (8). However, shale oil presents an entirely new set of analytical and refinery problems because of the very high proportions of unsaturates (about 20%)and of nitrogen compounds (about 40%) ( 3 ) . Shale oil naphthas (up t o 200” C. a t 760 mm.) may contain from 0.8 to 1.1% sulfur and 0.5 to 0.9% nitrogen. Although these naphthas are only light yellow immediately after distillation, they turn black within a few days ( 1 ) . The poor color stability and unpleasant odor of shale oil distillates are believed to be caused by the presence of nitrogen compounds (10). Very little separation with respect to sulfur and nitrogen is 1 Present address, Callery Chemical Co , Callery, Pa.

achieved by distilling total ciude shale oil as exemplified by the data of Stevens, Dinneen, and Ball (11) in Table I. These data also illustrate that nearly half of the crude shale oil cannot he distilled by the usual distillation procedures. Hence, it is logical to seek a technique which might answer the major prohlems peculiar to shale oil. The present work was undertaken to dptermine whether 01 not elution chromatography could aid 111 the development of satisfactory assay methods for crude shale oils.

Table I.

Distillation of Colorado Total Crude Shale Oil Obtained from N-T-U Retort [Stevens, Dinneen, and Ball ( 1 1 ) ] B P. Distillation Range, Pressure, Weight, ‘(2. Mm H g %

Sulfur, Nitrogen,

%

%

‘Totnl c r i i d e s h a l ~

Residuum

...

...

48.0

. 0.70

WORK O F PREVIOUS INVESTIGATORS

Apparently no previous work has been done o n chroniatographic fractionation of total crude shale oil. Some chromatography of shale oil distillates has been carried out, but these distillates and the total shale oil are very dissimilar. Conventional total crude shale oil is a heavy, thixotropic, black, high-boiling liquid with a high pour point and a high asphaltic content.

ANALYTICAL CHEMISTRY

1842 The chromatography of shale oil distillates is divided into two entirely different techniques: elution chromatography (employed in the work of this laboratory) and displacement chromatography. One of the first examples of elution chromatography of a shale oil distillate is that by Berenblum and Shoental in 1943 ( 2 ) .

l a h l e 11. Investigators Adsorbent rliarge type

They isolated carcinogenic constituents of the "blue" distillate of a shale oil by charging a 1% petroleum ether solution of the distillate to a column of activated alumina 2nd eluting with pptroleum ether, followed by increasing proportions of benzene in petroleum ether until purr: hrnzene was used as the last eluant. Later work on elution chromat o g r a p h y of distillates \vas carried out by Pronina ( 7 ) and Elution chromatography of Shale Oil Distillates and Total Crude Shale Oil by Smith, Smith, and Dinneen Smith. Smitli, and Dinneen (9) Florid Heavy gas oil

Berenblurn and Shoental ( 2 ) Activated alumina "Blue" Distillate

Pronina ( 7 ) Silica gel 225-3000 C. b.p. fraction

(9).

This JTork

~

Activated alumina Total sliale oil"

One of the first examples of displacement chromatography of a shale oil distillate is that by Dinneen, Bailey, Smith, and Ball in 1947 ( 4 ) . They charged, for instance, a dicitillate (boiling point, 131.8" to 135.4' C.) to a column of silica gel and folloned thici n-ith 2-propanol. This d e s o r b e n t displaced essentially bhe entire charge in front of it. -1mixture of paraffins arid naphthenes constituting 40% of the c h a r g e \vas c o l l e c t e d first, followed hy 3470 olefins, 21y0 aromatics and, mixed ivith the last portion of the aromatics, 4.Syo sulfur compouiids and 0.1% nitrogen c o m p o u n d s . Similar work on 200' to :325" Cy.

Bauxite Total shale oilh 1 7 0 , ii7

1.t

Kluant

Pentanr

__

I'etroleuiii etherc

-

l'raction Petroleiim rtlier'i

n-I'entani

..

J d .I

Sone Pre.wn t

0.11

0 li3

n-Pentane

44 i, 0 00 0 18

38 4 0 00 0.0li

2nd Fraction

Eluant

3lethanol

Benzenr

Benzene

...

41 3 3 73 0 i>7

Eluant

Pet. ether benzene

Xone

Acetone

... ...

31 8 1 80

...

Present Present

...

3rd Fraction Benzene

...

...

Benzene 22 5 1 09 1 44

1 28 2.5

1.01

c;

ethyl alcohol in benzrnr

25 vol q ethyl slcollol in benzene

33 3

T'resrnt ,.. 2 93 Present ... 0 67 a Charge introduced as solution in 1 volume of cyclohexane. b Charge int,roduced as solution in 2 volumes of cyclohexane. C First fraction received by percolation of sample dissolved in 2 volumes of petroleum efller a Sample introduced as solution in 99 volumes of petroleum ether.

...

41 8 3 27 0 52

Table 111. Elution Chromatography of Total Crude Shale Oil Run

Charge Diluted with about 1 vol. cyclohexane 0.67% S, 1.7% N

Adsorbent Fraction Aluinina

Eluant

1

n-Pentane

2

Benzene

3

25 vol YCethyl alcohol in benzene

% of W t . % S % Total

Description Colorless thixotropic oil. pleasant odor, blur fluorescenceb Broxn-black semisolid, musty odor, no fluorescence Brown-black semisolid, musty odor, brown Huorescence

44.6

0.00

31.3

1.80

33.3

2.93

0.00

Diluted with about 1vol. cvclohexane, 0.67% B. 1.7% S

.Iliinuna

109.3

1

n-Pentane

2

$5 ethyl alcohol in pentane 25 vol Yo ethyl alco-

3

5 rol

hol in benzenr

Yellow tint in colorless thixotropic oil, pleasa n t odor, blue fluorescence Brown-black semisolid. mustv odor. brown Huorescence Brown-black solid. phenolic odor, no Huorescence

Diluted with ahout 2 vol cvclohexane, 0 (37% 1 7'3 N

Aluniina

s,

1

n-Pentane Cy c 1oh ex an e Carbon tetrachloride

4

2 5 % vol. ethyl alco-

hol in benzene

Colorless oil, pleasant odor, blue Huorescence Yellow oil, pleasant odor, blue fluoresrence Brown-black semisolid, charred odor, no fluorescence Brown-black seniisolid. musty odor, brown Huorescence

Alumina

1 2

Carbon tetrachloride

3

23 rol, Yc ethyl alrohol In benzene

Brown-black thixotropic oil. pleasant odor, no fluorescence Brown-black semisolid, musty odor, no fluorescence Brown-black semisolid, must>- odor, brown fluorescence

Diluted with about 2 vol cyclohexane, 0.67% S, 1.7% N

Bauxite

Bauxite

1

Cyclohexane Carbon tetrachloride

3

2 5 vol, % ethyl alcohol In benzene

Total 1

n-Pentane

2

Benzene

3

25 vol. % ' ethyl alco-

hol in benzene Total Braun-Shell volumetric sulfur analyses; others are bomb-gravimetric b I n ultraviolet light.

Colorless oil, pleasant odor, light blue Ruorescence Brown-black semisolid, musty odor, nonHoorescent Brown-black semisolid. musty odor, brown fluorescence Colorless thixotropic oil, pleasant odor, nonHuorescent Brown-black seniisolid, musty odor, nonfluorescent Brown-black seinisolid. musty odor, brown Huorescence

57.4

0.67"

33.3 ~105.1

0.00

O.1RQ

12.2

2.4

76.7

0.95"

77.0

17 1

0.82''

__

45.2

0.02

0.5

4.1 23.3

0.00 2.17

00.0

31 5

3.14

58.2

10 8 ~~

93.8

100.0 0.13"

7 D

29.8

88.5

...

0.08

2.1

0 38"

24 7

28.1

2 29

37.6

1.04"

43 ti

31.5

3.31

81.4

0.08

43.5

,

.

,

32 0

~

103.1

2

59.8

0.00

~

Total

12.0

1.2W

43.1

105.2

Cyclohexane

0.18"

33.1

~~

Total Diluted with about 1 vol. cyclohexane, 0 67% S, 1.7% X

q of Totals

54.3

100.2

2 3

S

90.5

8.8 3.3

Total

S

__

~

Total

LY

101,l

38.0

0.00

I(i.0

1.30

49.9

io0 3 0 47=

2ii 7

12 2

1.37"

32 7

0.79

58.8

O.OG'

118.2 3.4

0.00

2.89

84.9

103.9 38.4

0.00

97.1 0.0

22.5

1.09

14.4

1 44"

48 4

41.8

3.27

80.5

0.62"

32 4

-

102.7

__

-

-

94.4

84.2

1843

V O L U M E 2 6 , NO. 11, N O V E M B E R 1 9 5 4 boiling point shale oil distillates was done later by Dinneen, Thompson, Smith, and Ball using 1-octanol or cyclohexanol as the desorbent ( 5 ) . Three examples of elution chromatography of shale oil distillates by previous investigators are presented in Table I1 along with two examples of elution chromatography of total crude shwle oil by this laboratory. EXPERIMENTAL

The authors have investigated a procedure for elution chromatography of total crude shale oil which is fundamentally the same as the technique developed for elution chromatography of crude petroleum oils (6). The total crude shale oil (from a S T U retort) was dissolved in an approximately equal volume of cyclohexane (about 6-gram charge and about 10 ml. of diluent) and introduced to a bed of about TO ml. of activated alumina (Alcoa, F-20, 80- to 200-mesh) or activated bauxite (regular iron Porocel, 2% volatile matter, 60- to 100-mesh) in a 2-foot column. The oil charge was followed by about 130 ml. each of three or four successive eluants which removed essentially all of the charge from the adsorbent. The eluates or fractions of the charge were then recovered from their solutions by room temperature evaporation to constant weight under a stream of air. The evaporation should be conducted in an inert atmosphere if analyses are to be made for easily oxidized components. Descriptions of these fractions are presented in Table 111. Runs 1, 2, and 3 demonstrate that n-pentane eluted about 15 weight % of a colorless oil with 0.00 weight % of nitrogen and about 0.16 weight % of sulfur when total crude shale oil was fractionated on activated alumina. In run 2, 5 volume % of ethyl alcohol in pentane eluted a large proportion of the material removable from alumina with 25 volume yoof ethyl alcohol in benzene. In run 3, cyclohexane, following n-pentane, eluted a yellow oil with 0.00 weight % of nitrogen, whereas in run 4 cyclohexane, as a first eluant in place of n-pentane, eluted a brown-black oil with 0.08 weight % of nitrogen. Conversely, in run 5 on activated bauxite, instead of activated alumina, cyclohexane as n first eluant eluted a colorless oil with 0.00 weight yo of nitrogen. Runs 5 :?nd 6 demonstrate that n-pentane or cyclohexane eluted about 38 weight yoof a colorless oil with 0.00 weight % of nitrogen and as little as 0.06 weight % of sulfur when total crude shale oil \v:ts fr:trtionated on activated bauxite.

The sulfur contents of one or more of the fractions of run 5 are probably in error on the high side, as the sulfur recovery is considerably above 100%. Some of the sulfur values were obtained by the Braun-Shell volumetric sulfur analysis, which sometimes gives high values when nitrogen is present. All nitrogen analyses were obtained by the Kjeldahl procedure. The fluorescence colors w x e those observed in ultraviolet light. The colorless and yellow oils were all color stable. All of the total mass re, the difficulty coveries are slightly above 1 0 0 ~ odemonstrating of removing the higher boiling point solvents completely by room temperature evaporation. CONCLUSIONS

Elution chromatography on activated alumina or bauxite absorbents is an efficient and convenient method for recovering low-sulfur, nitrogen-free, colorless hydrocarbon mixtures from a total crude shale oil while yielding nitroeen-rich asphaltic concentrates containing most of the sulfur compounds originally present in the shale oil. These results demonstrate that the described procedure could be used effectively as a basis for (leveloping crude shale oil assay or refining methods. LITERATURE CITED

Ball, d. Y., Dinneen, G. U., Smith, J. R . , Bailey, C. W., and Van Meter, it., I d . E7LQ. Chem., 41, 581 (1949). Berenblum, 1.. and Shoental, I{,, Brit. J . Ezptl. Path., 24, 232 (1943).

Cady, W.E., and Seelig, H. S.. I n d . Ezg. ('hem., 44, 2636 (1952). Dinneen, Q. U., Bailey, C. R., Smith, d. R., and Ball, J . S., ASAL. CHEY.,19, 992 (1947).

Dinneen, 0. U.. Thompson, C. J., Smith, .J. H., and Ball, ,J. S., [hid..2 2 , 8 7 1 ( 1 9 5 0 ) . Karr, C., 3r.. Weatherford, W.D., Jr., and Capell, R. G., Ibid., 26,262 ( 1 9 5 4 ) .

Proniiin. .\I. V., Doklady d k a d . S a i r k S.S.S.R., 74, 115 (1050). Sherwood. I . 1'. IT., Petwleurn Refiner, 31, 97 ( 1 9 5 2 ) . Smith, J. It., Smith, C. It., ,Jr,, and Dinneen, G. U., ANAL. C H E Y . , 22,

867 ( 1 9 5 0 ) .

Smith, W..\I., Landrum, T. C..and Phillips, G. E., I x d . Eng. C h e w . , 44, 586 (1952).

Steveii.3, It. F.,Dinneen, G . U., and Ball. ,J, S., U. S. Bur. .\lines. Rept. I w c s t . 4898 (1952). R E C E I V E io!. D review .Ipril 9, 1954. .Iccrpted .July 12, 193.1. Contiihution from t h e l l u l r i p l e Fello~vsliipof Gulf Reaearrli & Drwlopnirnt C o . . lIellon Institutc, Pittshurph, Pa

Standardization of Sieves and Determination of Grain Size of Granulated Sugar JULIAN

R. JOHNSON and JOHN S. NEWMAN

The Amalgamated Sugar Co., Ogden, Utah

A rapid two-sieve procedure reliably yields information from which the average grain size and uniformity of grain size of crystalline products such as sugar can be seen at a glance. Two methods for calibrating the sieves for effective opening are described.

T

HIS paper groups together the two most important functions of any sieving operation: standardization of the sieves and ttnalysis of the data obtained from the actual sieving operations. Standardization of the sieves is necessary because the manufarture of sieves is never perfect and there results considerable variation in the actual opening of sieves nominally the same size. In addition, with repeated use, there is a certain amount of varixtion o n ing to wear or coating of the wire mesh and it is nrcessary

to recalibrate the sieves from time to time. One method of calibrating sieves would be by the actual measurement of the openings. This requires microscopes and special equipment and techniques that are beyond the means of the ordinary user of sieves. This method gives only an average and does not' consider the effect of one or more large openings averaged with man)smaller ones and vice versa. An alternative method of calibration involves the use of a standard reference material for which size and shape distribution are kn0a.n. The sieves are thus calibrated by sieving a known material. T\vo methods of this latter type were tested in the authors' lahoratories and were found to be reliable. With reference to the presentation of the actual sieve test data, Powers ( 2 ) , in England, has shown that many materials, especially sugars, often conform to the arithmetic probability law.