選擇三種無機化合物作為分離液的材料：溴化鋅、氯化鋅、碘化鉀，分別配置不同比重的溶液，將煤樣浸泡其中，再水洗及直接烘乾後進行熱裂分析。發現水洗過的樣本在各參數上都能回復至平均值；浸泡樣本部份則會因分離液材料熔點較低產生的包覆作用使Tmax提前、S2參數值降低，且分離液的比重愈大影響愈明顯。浸泡分離液對TOC的影響則是因分析樣品淨量不同所導致，水洗後亦可回復。綜合三種分離液的影響，以溴化鋅浸泡樣最接近線性行為，且水洗效果良好、價格低廉，故選用溴化鋅為分離液。
分離煤素質使用的煤樣是台灣中新世石底層之高揮發份煙煤，採自台北縣三峽鎮裕峰煤礦。選擇了三個分離區間：比重<1.22的部份可富集40%的膜煤素，約為原樣的三倍；比重1.30-1.35則以鏡煤素為主，又含少量的膜煤素；比重>1.35的部份由於膜煤素減少，使鏡煤素所佔比例提高。熱裂分析的結果發現，經過富集的煤素質組成可表現出煤素質的特性。在比重<1.22的煤樣中，Tmax、S3較低、S2則較大，表示具有較多碳氫化合物；比重>1.35的趨勢則相反，Tmax、S3較高、S2則較小，可能是由於比較上含較多曾受氧化的有機物；至於比重1.30-1.35的部份則在各參數上的數值皆居前兩者之間。在S1上則看不出有顯著隨比重變化的趨勢。但S1較易受到水洗的影響而流失，容易被低估，是需要注意的地方。

Three chemical compounds, zinc bromide, zinc chloride, and potassium iodide, were chosen as density liquids. Coal samples were soaked in different density liquid, then washed and dried for pyrolysis. It revealed that pyrolytic parameters could be resumed back to their original values after washing. Furthermore, chemical compounds with low melting point were expected to wrap the coal particles and causing Tmax advanced, and S2 decreased. This influence is more conspicuous when higher density liquid is prepared. As for the effect of TOC is attributed to the inclusion of chemical compounds. Based on the overall effect of density liquid in pyrolysis, zinc bromide is finally chosen as the density liquid for separation because of its better linear correlation, low price, and cleanness after washing.
The sample used is high volatile bituminous coal form Miocene Shihti Formation in Taiwan, collected from Yu-Feng mine near Sanshia, Taipei County. Three maceral mixtures were prepared after specific gravity 1.22, 1.30, 1.35 were chosen as thresholds for separation. The separation results indicate that the macerals with specific gravity <1.22 had 40% exinite about triple enrichment of the original sample; macerals with specific gravity 1.30-1.35 were primary vitrinite and some limited exinite; macerals with specific gravity >1.35, contained very few exinite. In the pyrolysis, the macerals with specific gravity <1.22 exhibit lower Tmax and S3, and higher S2. On the other hand, macerals with specific gravity >1.35 exhibit higher Tmax, S3, and lower S2. As for the parameters of macerals with specific gravity 1.30-1.35 were in between of the previous two maceral mixtures. Finally, there was no notable variation in S1 with specific gravity. However, it is noticed that S1 might be underestimated after washing.

ASTM, 1975, Standard D-2797, ASTM Standard manual, Part 26, pp.350-354.
ASTM, 1977, Classification of coals by rank, D 388-77.
ASTM, 1980, Standard D-2797, Microscopical determination of volume percent of physical components in a polished specimen of coal, ASTM. Philadelphia, Pa.
Barker, C., 1974, Pyrolysis techniques for source-rock evaluation, The American Association of Petroleum Geologists Bulletin, V.58, N.11, pp.2349-2361.
Barker, C., 1996, Thermal modeling of petroleum generation: theory and applications, Elsevier Science B. V., Amsterdam— Lausanne- New York— Oxford— Shannon— Tokyo, 512p.
Baskin, D. K., 1997, Atomic H/C ration of kerogen as an estimate of thermal maturity and organic matter conversion, The American Association of Petroleum Geologists Bulletin, V.81, N.9, pp.1431-1450.
Bensley D. F. and Crelling, J. C., 1992, Low intensity spectral analysis (LISA) of coal macerals and the assessment of DGC fractions, Organic Geochemistry, V.18, N.3, pp.365-372.
Birtek, N., 1987, M.S. Thesis, University of Witwatersrand, S. Africa.
Bustin, R. M., 1991, Quantifying macerals: some statistical and practical considerations, International journal of coal geology, V.17, pp.213-238.
Burgess, J. D., 1974, Microscopic examination of kerogen ( dispersed organic matter) in petroleum exploration, Geol. Soc. Am. Special Paper 153, pp.19-30.
Clementz, D. M., 1979, Effect of oil and bitumen saturation on source-rock pyrolysis, The American Association of Petroleum Geologists Bulletin, V.63, N.12, pp.2227-2232.
Cloke, M., Clift, D.A., Gilfillan, A.J., Miles, N.J., Rhodes, D., 1994, Liquefaction of density separated coal fractions, Fuel Processing Technology, V.38, pp.153-163.
Cloke, M., Gilfillan, A.J., and Lester, E., 1997, The characterization of coals and density separated coal fractions using FTIR and manual and automated petrographic analysis, Fuel, V.76, pp.1289-1296.
Dormans, H.N.M., Huntjens, F.J., and van Krevelen, D.W., 1957, Chemical structure and properties of coal XX-composition of the individual macerals (vitrinites, fusinite, micrinites and exinites), Fuel, V.36. pp.321-339.
Dulhunty, J. A. and Penrose, R. E., 1951, Some relations between density and rank of coal, Fuel, V.30, pp.109-113.
Dyrkacz, G.R. and Horwitz, E. P., 1980, Separation of coal macerals, Fuel, V.61, pp.3-12.
Dyrkacz, G.R., Bloomquist, C.A.A., and Ruzcic, Ljiljana, 1983, Chemical variation in coal macerals separated by density gradient centrifugation, Fuel, V.63, pp.1166-1173
Espitalie, J., 1977, Source rock characterization method for petroleum exploration, 9th Offshore Technology Conference, pp.439-444.
Garcia-Vallès, M., Vendrell-Saz, M., and Pradell-Cara, T., 2000, Organic geochemistry (Rock-Eval) and maturation rank of the Garumnian coal in the central Pyreness (Spain), Fuel, V.79, pp.505-513.
Gilfillan, A., Lester, E., Cloke, M., and Snape, C., 1999, The structure and reactivity of density separated coal fractions, Fuel, V.78, pp.1639-1644.
Giraud, A., 1970, Application of pyrolysis and gas chromatograph to geochemical characterization of kerogen in sedimentary rocks, The American Association of Petroleum Geologists Bulletin, V.54, N.3, pp. 439-455.
Harwood, R. J., 1977, Oil and gas generation by laboratory pyrolysis of kerogen, The American Association of Petroleum Geologists Bulletin, V.61, N.12, pp.2082-2101.
Horton, H., 1952, Separation of coals into fractions of different densities, Fuel, V.31, pp.341-354.
Huang, H., Wang, S., Wang, K, Klein, M. T., and Calkins, W. H., 1999, Thermogravimetric and Rock-Eval studies of coal properties and coal rank, Energy & Fuels, V.13, pp.396-400.
Hunt, 1996, Petroleum geochemistry and geology (2nd ed.), W. H. Freeman and Company, New York, 743p.
Karas, J., Pugmire, R. J., Woolfenden, W. R., Grant, D. M., and Blair, S., 1985, Comparison of physical and chemical properties of maceral group separated by density gradient centrifugation, International journal of coal geology, V.5, pp.315-338.
Kinghorn, R.R.F., and Rahman, M., 1980, The density separation of different maceral groups of organic matter dispersed in sedimentary rocks, Journal of Petroleum Geology, V.2. N.4, pp.449-454.
Kinghorn, R.R.F., and Rahman, M., 1983, Specific gravity as a kerogen type and maturation indicator with special reference to amorphous kerogens, Journal of Petroleum Geology, V.6, N.2, pp.179-194.
Lanford, F. F., and Blanc-Valleron, M. -M., 1990, Interpreting Rock-Eval pyrolysis data using graphs of pyrolizable hydrocarbons vs. total organic carbon, The American Association of Petroleum Geologists Bulletin, V.64, pp.799-804.
Maroto-Valer, M. M., Taulbee, D. N., and Hower, J. C., 1999, Novel separation of the differing forms of unburned carbon present in fly ash using density gradient centrifugation, Energy & Fuels, V.13, pp.947-953.
Rahman, M. and Kinghorn, R.R.F., 1995, A practical classification of kerogens related to hydrocarbon generation, Journal of Petroleum Geology, V.18, pp.91-102.
Rimmer, S. M., Cantrell D. J., and Gooding, P. J., 1993, Rock-Eval pyrolysis and vitrinite reflectance trends in the Cleveland Shale member of the Ohio Shale, eastern Kentucky, Organic Geochemistry, V.20, N.6, pp.735-745.
Rubiera, F., Parra, J.B., Arenillas, A., Hall, S.T., Shah, C.L., and Pis, J.J., 1999, Texture properties in density-separated coal fractions, Fuel, V.78, pp.1631-1637.
Selly, R. C., 1985, Elements of petroleum geology, Academic Press ( 2nd ed. ), San Diego-London-Boston-New York-Sydney-Tokyo-Toronto, 470p.
Stach, E., Mackowsky, M-Th., Teichmüller, M., Taylor, G. H., Chandra, D. and Teichmüller, R., 1982, Stach’s Textbook of coal petrology (3rd ed.), Berlin Stuttgar, Gebruder Borntraeger, 535p.
Stankiewicz, B. A., Kruge, M. A., and Crelling, J. C., 1994, Density gradient centrifugation: application to the separation of macerals of type I, Ⅱ, and Ⅲ sedimentary organic matter, Energy & Fuels, V.8, pp. 1513- 1521.
Taulbee, D, Poe, S. H., Robl, T., and Keogh, B., 1989, Density gradient centrifugation separation and characterization of maceral groups form mixed maceral bituminous coal, Energy & Fuels, V.3, pp.662-670.
Thomas, L., 1992, Handbook of practical coal geology, John Wiley & Sons Ltd, Chichester-New York-Brisbane-Toronto-Singapore, 338p.
Ting, F. T. C., 1978, Petrographic techniques in coal analysis. In: Karr, C., Jr. (ed.): Analytical Methods for coal and coal products, Academic Press Inc., New York, pp.3-26.
Tissot, B. P. and Welte, D. H., 1984, Petroleum formation and occurrence (2nd ed.) , Springer-Verlag, Berlin- Heidelberg- New York, 699p.
van Krevelen, D. W., 1961, Coal. Elsevier scientific publishing Co., Amsterdam-London-New York-Princeton, 514p.
Waples, D. W., 1985, Geochemistry in petroleum exploration, D. Reidel Publishing Co. Dordrecht- Boston- Lancaster. 232p.
White, A., Davies, M. R., and Jones, S.D., 1989, Reactivity and characterization of coal maceral concentrates, Fuel, V.68, pp.511-519.
何春蓀，1966，台灣北部石底層之研究，台灣省地質調查所彙刊 第十七號，第1-7頁。
何春蓀，1975，台灣地質概論台灣地質說明書，經濟部中央地質調查所出版，共163頁。
孫立中，1992，台灣竹苗地區煤岩學及油氣生成之研究，國立中央大學地球物理研究所碩士論文，共55頁。
孫立中，2000，抑制鏡煤素反射率之量測成因─以分離台灣裕峰煤樣為例，國立中央大學地球物理研究所博士論文，共81頁。
翁成敏，蔡雲開，張愛雲，1991，單一有機質顯微組分的分離與富集方法，中國東部找煤研討會論文彙編，第155-160頁。
游能悌，鄧屬予，1996，台灣北部中上中新統的岩相與沈積循環，地質 第15卷 第二期，第29-60頁。
游能悌，鄧屬予，1999，台灣北部大寮層與石底層之沈積環境，經濟部中央地質調查所彙刊 第十二號，第99-131頁。
鄔立言，顧信章，盛志緯，范成龍，童箴言，陳克明，1986，生油岩熱解快速定量評價，科學出版社，北京，共198頁。
黃榮茂，王禹文，林聖富，楊得仁，1992，化學化工百科辭典，曉園出版社。
蔡龍珆，1988，基隆－台北間煤層鏡煤素之共生次序含意，地質第8卷，1-2期，63-70頁。