Highly active limonite catalysts for direct coal liquefaction q Takao Kaneko a, * , Satoru Sugita b , Masaaki Tamura b , Katsunori Shimasaki b , Eiichiro Makino c , Lambok H. Silalahi d a Takasago Coal Liquefaction Center, Science and Technology Research Center, Mitsubishi Chemical Corporation, c/o Kobe Steel Ltd, Takasago Works, 2-3-1 Shinhama, Arai-cho, Takasago, Hyogo 676-8670, Japan b Department of Coal and Energy Project, Takasago Coal Liquefaction Center, Kobe Steel Ltd, Takasago Works, 2-3-1 Shinhama, Arai-cho, Takasago, Hyogo 676-8670, Japan c Coal Liquefaction Project Of®ce, Nissho Iwai Corporation, 3-1, Daiba 2-chome, Minato-ku, Tokyo 135-8655, Japan d Coal Liquefaction Project, Agency for the Assessment and Application of Technology, BPPT New Building 22nd Floor, Jl. M.H. Thamrin No. 8, Jakarta 10340, Indonesia Received 8 May 2001; revised 2 November 2001; accepted 2 November 2001; available online 10 April 2002 Abstract The properties of limonite in Australia and Indonesia were examined by using X-ray diffraction, Mo Èssbauer spectroscopy, Thermal gravimetric analysis TGA) and TEM±EDX in relation to the catalytic activities in the liquefaction of low-rank coals. The molar ratio of H 2 O/FeinlimonitewasdeterminedfromtheweightlossresultingfromthedehydrationreactionofFeOOHtoFe 2 O 3 duringheatingfrom120 to400 8CinTGA.TheH 2 O/Femolarratiovariedfrom0.06forhematiteto0.60forlimoniteYY,dependingonthehematitecontent.Results fromthepulverizationtestsshowedthatthehighervalueofH 2 O/Femolarratioresultedinlesserabrasionofmediumballs.Auniquelimonite YY in Australia, containing no hematite, was easily pulverized to sub-micron particle size and showed an excellent oil yield in coal liquefaction. It appeared that H 2 O/Fe molar ratio could be one of the most important factors to select the better limonite catalyst for coal liquefaction. Moreover, it was found that Ni containing limonite SO in Indonesia exhibited a higher liquefaction activity than YY catalyst, because of transformation into a smaller crystallite size of pyrrhotite Fe 12x S). The agglomeration of pyrrhotites may be suppressed by a strong interaction between FeOOH and AlOH) 3 such as Fe±O±Al. TEM±EDX analysis suggests that Ni may be located near the Fe 12x S structure. Oil yield was signi®cantly increased from 43 to 62 wt% daf by CLB addition to the coal slurry in the liquefaction of Banko coal. FinelypulverizedlimonitecatalystSO)canbeadvantageouslyusedinacommercialplantforcoalliquefactioninIndonesiaduetothelow catalyst cost and a high liquefaction activity to obtain a high oil yield. q 2002 Elsevier Science Ltd. All rights reserved. Keywords: Coal liquefaction; Limonite catalyst; Pyrrhotite 1. Introduction The rapid economic growth in Asian countries with large populations requires huge amount of energy, especially transportation fuels. Limited growth in petroleum supply has brought a signi®cant gap between supply and demand ofthefuel.Currentadvancedliquefactiontechnologiesindi- cateareductionincostofthelique®edoiltothelevelof$20 perbarrelsothatitmaycompetewiththecurrentpetroleum crude oil prices. Directcoalliquefactioncouldbecomeaviableoptionfor the production of transportation fuels in Asian countries with cheap and abundant low-rank coals. In 1997, China signed agreements with the state government of West Falen Germany, Hydrocarbon Technologies Incorporation HTI) of the United States and NEDO of Japan to execute feasibility studies for the construction of direct coal lique- faction plants in China [1]. In 1999, NEDO exchanged the Memorandum of Understanding MOU) to execute a feasi- bility study for the construction of a direct coal liquefaction plant using the Improved BCL process with the Agency of the Assessment and Application Technology BPPT) of Indonesia [2]. The Improved BCL process has been devel- oped by NBCL Nippon Brown Coal Liquefaction Co. Ltd) through the successful completion of 50 t/d pilot plant project in Morwell, Australia 1980±1993), followed by research in Takasago Coal Liquefaction Center TCLC) of Kobe Steel Ltd. Recently, several researchers have made considerable efforts to develop highly dispersed iron-based catalysts for directcoalliquefaction.Theresultsofsomestudiesindicate that quite large crystallites or agglomerates can be formed Fuel 81 2002) 1541±1549 0016-2361/02/$ - see front matter q 2002 Elsevier Science Ltd. All rights reserved. PII:S0016-236102)00079-0 www.fuel®rst.com * Correspondingauthor.Tel.: 181-794-45-7320;fax: 181-794-45-7514. E-mail address: xlm10600@nifty.ne.jp T. Kaneko). q Published ®rst on the web via Fuel®rst.comÐhttp://www.fuel®rst.com