Characterization of the oil extracted from Chinese Maoming oil shale

Short Communications 0 SIOZ

c

quartz

t

A12St20S(OH14 kaollmte Fe, -,S pyrrhotite

*

IlllW

* CaSOa anhydrm

5

10 15 20

25

l

N~~(AISIO~,)&O~

’

Fe&

30 35 2 Theta

natrodavyne

pyrite

40 45

50

55

Figure 1 XRD spectra of Illinois No. 6 low temperature ash: a, Ni-filtered CuKa radiation i. = 0.154 18 nm; b, residual products after liquefaction catalysed by KOH; c, residual products after liquefaction catalysed by Na,CO,

In fact, the recovered water solutions runs 242 and 185 are no more effective catalysing the WGSR and as consequence, the coal conversion was shown in Table 1.

increase of the relative quantity of illitetype clay, as shown by the increase of 001 line diffraction intensity; correspondingly a strong decrease of the relative quantity of crystalline kaolinite was observed, confirming that kaolinitic clays reacted with sodium carbonate producing both natrodavyne and illite-type compounds. In the case of the potassium hydroxidecatalysed reaction, the formation of new aluminosilicate phases was not observed, but the very strong increase in relative quantity of the illite-type crystalline phase (Figure Ic) and the corresponding decrease of crystalline kaolinite, suggested that some potassium reacted with kaolinite (alkali-free) to give a typical potassium clay of the illite family. A semiquantitative evaluation (internal standard: fluorite) indicated an approximate doubling of the relative quantity of crystalline illite with a corresponding halving of the relative quantity of crystalline kaolinite in comparison with the same phases in the starting mineral matter of Illinois No. 6 coal (Figure 1~).

It is concluded that insoluble mineral reduces the effective catalyst that is active limits the possibility and recycle.

Characterization

of the oil extracted

Toshitaka

and Noriaki Wakao

Funazukuri

Department of Chemical Engineering, (Received 2 December 1987)

Yokohama

National

Chinese

University,

a as

1

the production of phases probably amount of WGSR in the process, and of catalyst recovery

from

in

REFERENCES

CONCLUSIONS between the mineral matter, particularly clays, and the catalysts. The sodium carbonate gave rise to the formation of a sodium aluminium carbonate silicate (natrodavyne) (Figure Ih) and to an

of

Fischer, F. and Schrader. H. Brennst. Chem. 1921,2, 257 2 Appell, H. R., Miller, R. D., Illig, E. G.. Moroni, E. G., Steffgen, F. W., US Dept. of Energy, Rep. PETC.TR-79:l, September 1979 Oelert, H. R. and Siekmann. R. Fuel 1976, 55, 39 Ross, D. S. and Blessing, J. E. Fuel 1978, 57,379 Ross, D. S., Blessing, J. E., Nguyen, Q. C. and Hum, G. P. Fuel 1984.63, 1206 Ross, D. S., Green, T. K.. Mansani, R. and Hum, G. P. E/~rrgy ur~d Flrrls 1987. 1 (3), 287 7 Elliott, D. L. and Sealock. L. J. Jr. lnd. Eng. Chem. Prod. Rrs. Dec. 1983,22,426 8 Elliott, D. L., Hallen, R. T. and Sealock, L. J. Jr. Inri. Eny. Chem. Prod. Res. Dec. 1983, 22, 431 9 Fu, Y. C. and Illig, E. G. Am Chem. Sot. Die. Fuel Chem. Prqr. 1982, 27, 254 10 Schuchardt, U. and Brito Sousa, M. F. Fuel 1986,65, 669 11 Hodges, S. and Creasy. D. E. Fuel 1985, 64, 1229 I2 Donovan, J. M., Molton, P. M. and Demmitt. T. F. Fuel 1981, 60, 898 13 Del Bianco, A. and Girardi, E., ‘Proc. 1987 International Conference on Coal Science’. Maastricht. 26 30 October 1987, p. 355

Maoming

Yokohama

oil shale

240, Japan

molecular weight distributions and absorbance ratios of CH,/CHJ for oil fractions obtained by supercritical fluid extraction of Maoming oil shale were studied. An increase in temperature resulted in an increase in molecular weight and/or chain length in the extraction products from oil fractions containing aromatic rings, whereas those from aliphatic rich fractions were temperature independent.

The

(Keywords: oil shale: extraction; supercritical)

Supercritical fluid extraction of Chinese Maoming oil shale with water and the effects of extraction temperature on the yields of oil fractions separated by adsorption chromatography have been studied previously’. This note describes the examination of the molecular weight distributions and absorbance ratios of the C-H asymmetric vibration of CH, to that of CH, for each oil fraction.

0016~2361/88/060875 %’ 1988 Butterworth

03f3.00 & Co. (Publishers)

Ltd.

EXPERIMENTAL The experimental apparatus and the components of Chinese Maoming oil used have been described shale elsewhere’. Briefly the extraction procedures were as follows: the extraction was carried out batchwise at a heating of 8SKmin-’ from room rate temperature to a prescribed final value and then rapidly cooling. The pressures

at the final temperatures were about 23 MPa when the temperatures were above the critical temperature of water, and when below that critical temperature the pressures were at the saturation vapour pressures of water. The oils extracted were recovered, and cyclohexane-soluble into separated components (CS) and cyclohexaneinsoluble/tetrahydrofuran-soluble com-

FUEL, 1988,

Vol 67, June

875

Short

Communications

b

a i

Elution 10000

1000

4 I 5000

I \ \ 773K \

volume

(ml1

200

I

I

I

Elution

Elution

(ml)

Molecular

weight

Molecular

weight

e

L

1

30

20 Elution

volume

10000

1000

(ml1 200

5000 500 Molecular

J

1

40

40

100

weight

Elution

volume

weight

Figure 1 G.p.c. scans of od fractions: a, n-penrane eluate; b, ethyl ether eluate; c, chloroform eluare; d. methanol eluate and e, cyclohexane msoluble/THF soluble components

878

FUEL, 1988, Vol 67, June

(ml)

weight

ponents (CIS). The CS components were further fractionated by silica geladsorption chromatography into npentane (PE), ethyl ether (EE), chloroform (CE) and methanol (ME) eluates. A liquid chromatograph with two columns connected in series (Hitachi Kasei, Gelpak GA110 and GA130,7 mm i.d. x 500mm) and provided with two detectors, u.v. at 254nm and refractive index (RI), was used 10 measure the scans of gel permeation chromatography (g.p.c.) of these eluates and CIS components. Tetrahydrofuran was used as a mobile phase at a flow rate of lmlmin~‘. In every measurement the fraction dissolved in THF (2 mg ml ‘) was Injected into the liquid chromatograph using a 20~1 sample loop. Elution volumes of the standard molecular weights were calibrated with polystyrene. Infrared spectra were measured by an FT-1.r. spectrometer Each spectrum was obrained by the co-addjlion of 100 interferograms at 2 cm _ ’ resolution from films cast from solutions in THF on a KBr disc. The disc was dried for 12 h at temperature under room vacuum conditions.

(ml)

lOODO 1000 200 I, I I 100 5000 500 Molecular

volume

100 10000 1000 IILL I 1 5000 5QO 200

100

I I 5000 500 200

d

1

volume

1ooao 1000 (,,I

100

500

Molecular

10

C

RESULTS

AND DISCUSSION

Gel permrution chromutograph} Figure 1 shows g.p.c. scans of the four eluates, PE, EE, CE and ME, and of the CIS components. The scans of PE were measured with the RI detectar,and those

Regional

2860cm-‘. 2924 cm ’

t1

Final

temperature

Final

(K)

temperature

(Kl

Figure 2 Absorbance ratios of CH,/CH, for: a: 0, n-pentane eluate; A. ethyl ether eluate; V, cyclohexane insoluble;THF soluble components and b: 0, chloroform eluate; 0, methanol eluate

of EE, CE, ME and CIS components with the U.V. detector. For EE, CE, ME and CIS fractions, excluding CE at 593 K, similar chromatograms were obtained in the temperature range from 593 to 708 K. The components having molecular weights higher than 500 (< 10000) increased with increasing temperature. On the other hand, the molecular weight distributions of PE were almost the same and independent of temperature in the range 593-708 K. In particular, the components having MW ~200 had the identical g.p.c. scans at these temperatures. However, the g.p.c. scans of all oil

fractions extracted at 773 K were different from those extracted at temperatures below 708 K, and the scans were found to shift to lower molecular weights.

Infrured

spectrci

2 shows the absorbance ratio of aersus final extraction temCH,/CH, perature. Maoming shale oil is highly ahphatic with aromaticities of 0.33-0.34 being reported* for the oils extracted with supercritical toluene and the spectra obtained contained the aliphatic C-H stretching bands near 2956, 2924 and

Victor

Moritz

Goldschmidt’s Chemistry,

This year is the centenary of the birth of V. M. Goldschmidt. An appreciation is given of his contributions to coal science, especially the geochemistry of trace elements, theories for their origin and enrichment, and suggestions for coal as a of trace elements, notably source germanium. do we owe SO of geochemstate than the late V.

‘To no other

individual

much

development

for the

istry to its present M. Goldschmidt’

L. H. Ahrens,

1954

The dominant band at the shoulder at and 2956cm-’ correspond to the asymmetric CH, and CH, vibrations, respectively3. The absorbance ratios of these peaks vary between shales because of differences in chain length in the aliphatic section of the kerogen and/or the presence of methyl group and aromatic rings3. It was found that the absorbance ratios of CH, to CH, in EE, CE, ME and CIS increased with increasing temperature, with marked temperature effects for EE and CE. On the other hand, the ratios of CH, to CH, in PE were nearly constant, slightly higher than unity and lower than those of other components in the range 638% 708 K, where most weight loss of oil shale occurred’. In conclusion, for the fractions containing aromatic rings (EE, CE, ME and CIS), more components with higher molecular weights and/or longer chains were extracted with increasing temperature. In contrast, the molecular weight distribution and aliphatic chain length in PE (rich in aliphatic components) were not affected by extraction temperature. At 773 K, the absorbance ratios for all fractions except the PE eluate decreased drastically, and the g.p.c. scans for all fractions were shifted to lower molecular weights. This is considered to imply that significant decomposition of extracts took place at about this temperature.

Figure

Regional

Dalway J. Swaine Department of Inorganic

News

contributions The University

REFERENCES

I Funazukuri, T., Yokoi, S. and Wakao, N. 2 3

Fuel 1988,67, 10 Qin, K. Z., Wang, R. A. and Jia, S. S. Enemy Sources 1984, 7, 231 Evans, E., Batts. B. and Cant, N. Furl 1987,66, 326

News

to Coal of Sydney,

Science NSW 2006,

It is 100 years since the birth of the eminent crystallographer and geochemist, Victor Moritz Goldschmidt. Goldschmidt regarded geochemistry as the study of the composition, distribution and migration of elements in the components of the earth, and of the principles underlying the various changes during geochemical cycling. This is covered concisely by V. I. Vernadsky’s definition of geochemistry as the history of terrestrial atoms. Goldschmidt was born in Zurich on the 27th January, 1888. but moved to

Australia

Kristiania (Oslo) in 1901 when his father became a Professor of Chemistry. At the early age of 23 he received a doctorate, and in 1914 was appointed to a chair at the University of Oslo. In 1929, he became Director of the Institute of Mineralogy and Petrography at the University of Gottingen, where he remained until 1935, when political events forced his return to Oslo. In 1942, he was arrested, but escaped to Sweden and ultimately to the UK where he was a guest of the Macaulay Institute for Soil Research, Aberdeen, and later of the

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