A Review of Coal Liquefaction Using Direct Coal Liquefaction (DCL) and Indirect Coal Liquefaction (ICL) Techniques


  • Mitha Puspitasari Universitas Pembangunan Nasional Veteran Yogyakarta
  • Mahreni Mahreni Universitas Pembangunan Nasional Veteran Yogyakarta




Coal Liquefaction, DCL, ICL


Coal liquefaction is a process of converting solid coal fuel into liquid fuel. This process is developed by various countries to overcome the scarcity of liquid fuels; therefore, this coal liquefaction is very useful for countries that have few petroleum reserves yet, have large coal reserves. There are two coal liquefaction techniques, namely direct coal liquefaction (DCL) and indirect coal liquefaction (ICL). In ICL, there is a gasification process that usually develops products, generating Fischer-Tropsch (F-T) liquid, methanol (CH3OH/MeOH), and dimethyl ether (CH3OCH3/DME). On the other hand, DCL involves a hydrogenation reaction to produce synthetic gasoline and diesel, which is the same as LPG, a hydrocarbon fuel product similar to hydrocarbon fuel derived from petroleum. This paper discusses the ICL and DCL coal liquefaction techniques, including the process stages, the type of catalyst used, and the products resulted from these techniques.


Comolli, A.G., Lee, L.K., Pradhan, V.R., Stalzer, R.H., Karolkiewicz, W.F., and Palacio, R.M., 1996, “Direct Liquefaction Proof-of-Concept Program," final report prepared by Hydrocarbon Technologies, Inc. (Lawrenceville, New Jersey, USA) and Kerr-McGee Corporation (Oklahoma City, Oklahoma, USA) for the Pittsburgh Energy Technology Center, US Department of Energy.

Dadyburjor, D., Liu, Z., 2004, "Coal liquefaction. In: Kirk-Othmer Encyclopedia of Chemical Technology” Vol. 6, fifth ed., Wiley-Interscience, Wiley, Hoboken, New Jersey, pp. 832–869.

Derbyshire, F.J., 1988, “Catalysts in Coal Liquefaction," IEACR/08, IEA Coal Research.


Hirano, K., and Kanda, Y., 2001, "Study on Industrial Catalyst for Bituminous Coal Liquefaction," Fuel Processing Technology, 72, pp. 35-45

Jin, E., Zhang, Y., He, L., Harris, H.G., Teng, B., and Fan, M., 2014, "Review: Indirect Coal to Liquid Technologies," Applied Catalysis: General 476, 158-174.

Kaneko, T., Tazawa, K., Okuyam, N., Tamura, M. and Shimasaki, K., 2000, "Effect Highly Dispersed Iron Catalyst On Direct Liquefaction of Coal," Fuel, Vol. 79, 263-271, Elsevier.

Kaneko, T., Makino, E., Sugita, S., Okuyama, N. and Tamura, M., 2002, “Liquefaction of Banko Coal with Limonite Catalyst," Indonesian – Japan Coal Liquefaction Seminar, NEDO-KOBELCO-BPPT, Jakarta, PP B3.1-B3.15.

Karaca, H., 2006, “ Effect of Coal Liquefaction Conditions on the Composition of the Product Oil," Energy Sources, 28, pp.1483-1492.

Larson, E. D., and Tingjin, R., 2003, "Synthetic fuel production by indirect coal liquefaction," Energy for Sustainable Development, Vol. VII, No. 4, 79-102.

Li, W., Bai, Z. Q., Bai, J., and Li, X., 2017. Transformation and roles of inherent mineral indirect coal liquefaction: A mini-review. Fuel 197, 209-216.

Liu, Z., Shi, S., and Li, Y., 2010. Coal Liquefaction Technologies—Development in China and Challenges in Chemical Reaction Engineering. Chemical Engineering Science, 65, 12-17

Marco, I. and Chomon, M.J., 1990, “Relationship Between Liquefaction Yields and Characteristics of Different Rank Coals," Elsevier Scientific Publishing No. 24. Chemical Engineering Department, Bilbao, Spain, pp. 127-133.

Moore, R., (retired Cost Engineer, Air Products and Chemicals Inc.), 2003. Personal communications.

Ningrum, N.S., Suganal and Prijono, H., 2009. Pengkajian Pengaruh Penambahan Nikel dan Krom pada Katalis Berbasis Besi untuk Pencairan Batubara. Jurnal Teknologi Mineral dan Batubara, Vol. 5, No. 3, July 2009: 131-137.

Schulz, H., 1999, "Short history and present trends of Fischer Tropsch synthesis, Appl. Catal. A Gen, 186, 3–12.

Shui, H., Cai, Z., and Xu, C., 2010., "Recent Advances in Direct Coal Liquefaction," Energies, 3, 155-170.

Silahahi, L. H., 2006, “Evaluasi Kinerja Katalis Limonit Soroako Proses Pencairan Batubara Banko Selatan”, Jurnal Energi dan Lingkungan, Vol. 2, No. 1, pg. 11-16.

Talla, H., Amijaya, H., Harijoko, A., and Huda, M., 2013,”Karakteristik batubara dan Pengaruhnya terhadap Proses Pencairan”, Reaktor. Vol. 14, No. 4, pg. 267-271.

Talla, H., and Taba, H. T., 2017,”Pencairan Batubara Peringkat Rendah Papua Menggunakan Katalis Bijih Besi”, Jurnal Rekayasa Kimia dan Lingkungan, Vol. 12, No. 2, pg. 94-102.

Turk, B.S., Merkel, T., Lopez-Ortiz, A., Gupta, R.P., Portzer, J.W., Krishnan, G.N., Freeman,

B.D., and Fleming, G.K., 2001,” Novel Technologies for Gaseous Contaminants Control,"

Contract DE-AC26-99FT40675 for US DOE by Research Triangle Institute, Research Triangle Park, North Carolina.

Vasireddy, S., Morreale, B., Cugini, A., Song, C., and Spivey, J., 2011, "Clean liquid fuels from direct coal liquefaction: chemistry, catalysis, technological status and challenges," Energy & Environmental Science, 04 (02), 311-345.

Williams, R.H., and Larson, E.D., 2003, "A comparison of direct and indirect liquefaction technologies for making fluid fuels from coal," Energy for Sustainable Development, VII (4) (this issue).