DOCSLIB.ORG

Removal of Iron from Titanium Ore Through Selective Chlorination Using Magnesium Chloride

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Removal of Iron from Titanium Ore Through Selective Chlorination Using Magnesium Chloride Materials Transactions, Vol. 54, No. 8 (2013) pp. 1444 to 1453 ©2013 The Mining and Materials Processing Institute of Japan Removal of Iron from Titanium Ore through Selective Chlorination Using Magnesium Chloride Jungshin Kang1,+ and Toru H. Okabe2 1Department of Materials Engineering, Graduate School of Engineering, The University of Tokyo, Tokyo 113-8656, Japan 2Institute of Industrial Science, The University of Tokyo, Tokyo 153-8505, Japan A selective chlorination process using magnesium chloride (MgCl2) as chlorinating agent was investigated with the aim of developing a process for removing iron directly from ilmenite, which is a low-grade titanium ore known as FeTiO3. Two crucibles, one consisting of titanium ore and the other consisting of a mixture of titanium ore and MgCl2, were placed in a gas-tight quartz tube, and then both crucibles were heated to 1000 K. In some experiments, H2O vapor was introduced in the quartz tube. HCl gas produced from the MgCl2/titanium ore mixture reacted with the iron present in the titanium ore placed in the other crucible to produce TiO2. Iron present in the titanium ore of the titanium ore/MgCl2 mixture reacted with MgCl2, and MgTiO3 and MgO were obtained. Iron in the titanium ore present in both crucibles was removed as FeCl2 (l,g). In these experiments, the effects of the particle size of the titanium ore and the atmosphere on selective chlorination were investigated. In addition, titanium ores produced in Vietnam, Australia and China were used as feedstocks. By the chlorination process, 97% TiO2 was obtained directly in one step from the low-grade titanium ore containing 51% TiO2 under certain conditions, thus demonstrating the feasibility of the selective chlorination process for producing high-purity titanium dioxide from low-grade titanium ore. [doi:10.2320/matertrans.M-M2013810] (Received March 26, 2013; Accepted May 15, 2013; Published July 25, 2013) Keywords: ilmenite, titanium ore, selective chlorination, synthetic rutile, iron removal, titanium smelting 1. Introduction Ilmenite (rock) Ilmenite (sand) Rutile : 30 – 50% TiO2 : 35 – 65% TiO2 : 95% TiO2 Titanium (Ti) is widely used in various fields because of its excellent properties such as high strength to density ratio and Slag process high corrosion resistance; in addition, titanium is the ninth 1) most abundant element on the Earth’s crust. However, 75 – 86% TiO2 (Ti slag) titanium is still used to a much lesser extent than iron (Fe) or aluminum (Al), mainly because of low productivity and UGS process Becher process Benilite process 1) high production costs involved at all processing stages. For 95% TiO2 90 – 93% TiO2 95% TiO2 example, the cost of processing titanium ore is 15 times higher (Upgraded slag) (Synthetic rutile) than that required for processing iron ore.2­5) To reduce the Sulfate process Chloride process Kroll process production costs, it is imperative to improve the early stages of titanium production by developing a simple and effective Titania pigment Titanium processes for processing titanium ore to titanium metal. (5.1Mt TiO2 / year world) (0.1Mt Ti / year world) Ilmenite and rutile are the key minerals used for titanium Fig. 1 Currently used process for titania pigment and titanium produc- production. Chemical formula of ilmenite is FeTiO3 with tion.1,6,8,9) 30­65% TiO2, while that of rutile is TiO2 with 95­100% 1,6,8,9) TiO2. If we consider only the concentration of TiO2, rutile will be the most appropriate feedstock for the to reduce the amount of iron in the TiO2 ore feed for reducing manufacture of titania (TiO2) pigment or titanium metal. the amount of chloride wastes and the chlorine loss during the However, ilmenite is used much more extensively as a chloride process16) or the Kroll process.17) Many companies feedstock. For example, the global production of ilmenite was place a lower limit on the purity of TiO2 feed before placing eight times higher than that of rutile in 2011.7) This is because the feed into the chlorinator. Usually the feeds containing at 18,19) the price of ilmenite is much lesser than that of rutile. Further, least 90% of TiO2 are used. Some countries including ilmenite is much more readily available than rutile, with the Japan have much more strict criteria for a purity of TiO2 feed, 7) share of ilmenite in the world mine reserves being 94%. and a purity of over 95% TiO2 is required in the Kroll process. Therefore, the role of ilmenite as the source for the titanium However, due to the increase in the price of the TiO2 feed by, mineral is expected to become gain more significance. for example, the increase in the consumption of TiO2 feed in As shown in Fig. 1, several processing stages are generally China, recently, some companies in Japan have begun to use 20) required for removing iron from titanium ore for producing 90% TiO2 feed in order to reduce the cost of the feedstock. TiO2 pigment or titanium metal using ilmenite as the In the Becher process, various types of titanium ores are feedstock.1,6,8,9) In many cases, first, ilmenite is upgraded to used as feedstocks.21) However, multiple stages are required 10,11) high purity TiO2 by the Becher process, the Benilite for treating iron, and a huge amount of iron compounds are process,12­14) or the slag production process.15) It is important dumped as wastes. In the Benilite process, processing of iron is simpler than the other processes. However, this process +Graduate Student, The University of Tokyo. Corresponding author, makes use of highly concentrated 18­20% HCl and only E-mail: [email protected] limited types of titanium ore is used as a feedstock.21) In the Removal of Iron from Titanium Ore through Selective Chlorination Using Magnesium Chloride 1445 Chlorinating agents slag process, iron in the titanium ore is reduced to metal by This study a carbothermic reaction, and TiO2 slag and iron metal are * separated. The scale of the slag process is large, and it is high Ilmenite (FeTiO3) HCl MgCl2 Ilmenite (FeTiO3) H2O speed process. However, TiO2 with a low purity of 75­86% is Selective chlorination Selective chlorination obtained. For obtaining high purity TiO2 slag, it is essential to employ additional upgrading process such as the upgrade HCl recovery H O TiO FeCl FeCl MgTiO / MgO HCl slag (UGS) process,15) which entails multiple steps for the 2 2 2 2 3 further removal of iron. * Extensive research has been conducted to improve the Ti scrap currently used upgrading processes of titanium ore. Among Titanium metal production Chlorine recovery the various processes, selective chlorination has gained fi signi cant attention. In the selective chlorination process, Ti metal Fe TiCl4 iron is only removed directly from the titanium ore as iron chlorides and high purity TiO is obtained. The selective Fig. 2 Flow diagram of the selective chlorination process investigated in 2 the present study. chlorination processes investigated so far have entailed 22­25) the use of chlorine gas (Cl2) under carbon or CO/Cl2 mixture atmosphere,26­28) or metal chlorides as the chlorine Gas outlet / Not used under vacuum and Ar atmosphere source.29­32) Among these processes, the first two processes Electric furnace Heater require Cl2 gas and installation of the reactor become costly Quartz crucible Mo-lined and it also has environmental issue for operation. quartz crucible Silicone Quartz Quartz The selective chlorination process that uses metal chlorides rubber plug wool [Mo] Ti ore MgCl was recently developed by Okabe et al.29,30) In recent studies, Quartz tube Ti ore 2 the authors investigated further improvement of the selective Vacuum or chlorination using calcium chloride (CaCl2) as the chlorinat- Gas inlet % Water bubbler used ing agent, and 97 TiO2 was successfully obtained directly Gas outlet Ar 31,32) Thermocouple under Ar + H O gas from titanium ore containing 51% TiO2 in a single step. 2 atmosphere only However, because CaCl2 was used as chlorinating agent, it MFC was needed to decrease the activity of CaO by the production Water Empty of complex oxides such as CaTiO for producing HCl gas. 3 Pump Pressure Temp. In addition, high purity TiO2 could not be obtained when the controller experiment was conducted under Ar gas flow atmosphere. gauge Recently, on the basis of thermodynamic analysis,33) it was Fig. 3 Schematic of the experimental apparatus used in the present study. anticipated that extracting chlorine source such as HCl gas from MgCl2 rather than CaCl2 is easier because HCl gas can Table 1 Chemical compositions of titanium ores used in this study. be produced even under standard state condition (aMgO = 1), % *1 and is possible even at lower temperatures. In this study, in Source country Concentration of element i, Ci (mass ) the viewpoint of improvement of HCl gas production and the of titanium ore Ti Fe Al Si Ca Mn Zr Nb Mg verification of feasibility for upgrading titanium ore by Vietnam*2 45.0 49.7 0.33 0.57 0.04 3.47 0.07 0.15 N.D. utilizing MgCl2 for the selective chlorination, the authors Australia*3 48.5 46.7 1.02 1.00 0.07 1.69 0.18 0.18 N.D. used MgCl2 as a chlorinating agent to remove iron directly China*4 47.2 45.4 1.41 1.65 0.21 2.79 0.24 0.27 N.D. from the titanium ore. *1 fl Determined by XRF analysis (excluding oxygen and other gaseous Figure 2 shows the ow diagram of the process used in elements), N.D.: Not Detected. Below the detection limit of the XRF this study.
Load more

Recommended publications
  • Editorial for Special Issue “Ore Genesis and Metamorphism: Geochemistry, Mineralogy, and Isotopes”
    minerals Editorial Editorial for Special Issue “Ore Genesis and Metamorphism: Geochemistry, Mineralogy, and Isotopes” Pavel A. Serov Geological Institute of the Kola Science Centre, Russian Academy of Sciences, 184209 Apatity, Russia; [email protected] Magmatism, ore genesis and metamorphism are commonly associated processes that define fundamental features of the Earth’s crustal evolution from the earliest Precambrian to Phanerozoic. Basically, the need and importance of studying the role of metamorphic processes in formation and transformation of deposits is of great value when discussing the origin of deposits confined to varied geological settings. In synthesis, the signatures imprinted by metamorphic episodes during the evolution largely indicate complicated and multistage patterns of ore-forming processes, as well as the polygenic nature of the mineralization generated by magmatic, postmagmatic, and metamorphic processes. Rapid industrialization and expanding demand for various types of mineral raw ma- terials require increasing rates of mining operations. The current Special Issue is dedicated to the latest achievements in geochemistry, mineralogy, and geochronology of ore and metamorphic complexes, their interrelation, and the potential for further prospecting. The issue contains six practical and theoretical studies that provide for a better understanding of the age and nature of metamorphic and metasomatic transformations, as well as their contribution to mineralization in various geological complexes. The first article, by Jiang et al. [1], reports results of the first mineralogical–geochemical Citation: Serov, P.A. Editorial for studies of gem-quality nephrite from the major Yinggelike deposit (Xinjiang, NW China). Special Issue “Ore Genesis and The authors used a set of advanced analytical techniques, that is, electron probe microanaly- Metamorphism: Geochemistry, sis, X-ray fluorescence (XRF) spectrometry, inductively coupled plasma mass spectrometry Mineralogy, and Isotopes”.
    [Show full text]
  • A Review of Flotation Separation of Mg Carbonates (Dolomite and Magnesite)
    minerals Review A Review of Flotation Separation of Mg Carbonates (Dolomite and Magnesite) Darius G. Wonyen 1,†, Varney Kromah 1,†, Borbor Gibson 1,† ID , Solomon Nah 1,† and Saeed Chehreh Chelgani 1,2,* ID 1 Department of Geology and Mining Engineering, Faculty of Engineering, University of Liberia, P.O. Box 9020 Monrovia, Liberia; [email protected] (D.G.W.); [email protected] (Y.K.); [email protected] (B.G.); [email protected] (S.N.) 2 Department of Electrical Engineering and Computer Science, University of Michigan, Ann Arbor, MI 48109, USA * Correspondence: [email protected]; Tel.: +1-41-6830-9356 † These authors contributed equally to the study. Received: 24 July 2018; Accepted: 13 August 2018; Published: 15 August 2018 Abstract: It is well documented that flotation has high economic viability for the beneficiation of valuable minerals when their main ore bodies contain magnesium (Mg) carbonates such as dolomite and magnesite. Flotation separation of Mg carbonates from their associated valuable minerals (AVMs) presents several challenges, and Mg carbonates have high levels of adverse effects on separation efficiency. These complexities can be attributed to various reasons: Mg carbonates are naturally hydrophilic, soluble, and exhibit similar surface characteristics as their AVMs. This study presents a compilation of various parameters, including zeta potential, pH, particle size, reagents (collectors, depressant, and modifiers), and bio-flotation, which were examined in several investigations into separating Mg carbonates from their AVMs by froth flotation. Keywords: dolomite; magnesite; flotation; bio-flotation 1. Introduction Magnesium (Mg) carbonates (salt-type minerals) are typical gangue phases associated with several valuable minerals, and have complicated processing [1,2].
    [Show full text]
  • Sedimentary Exhalative Deposits (SEDEX)
    Sedimentary Exhalative Deposits (SEDEX) Main charactersitcs:SEDEX deposits are stratiform, massive sulphide lenses formed in local basins on the sea floor. This is usually as a result of hydrothermal activity in areas of continental rifting. They represent major sources of lead and zinc with minor amounts of gold, barium and copper. Alteration is common especially in the form of silicification. Sedex deposits have many similarities with VMS deposits. Idealised SEDEX Deposit Model e.g. Mount Isa, Broken Hill (Australia), Sullivan (Canada), Silvermines (Ireland) Adapted from Evans 1997: Ore Geology and Industrial Minerals The stratiform lenses formed in Sedex deposits can be up to 40km thick and have a lateral extent of 100km's. Stockwork or vein mineralisation may occur beneath this. Host rock lithology varies from shales, siltstones and carbonates (low energy environment) to debris flows, conglomerates and breccias (high energy environments). Sedex deposits have been categorised in terms of a sedimentary basin hierachy. First order basins have lateral extents of hundreds of km's and maybe represented by epicratonic embayments ot intracratonic basins. Second order basins which can be up to tens of km's in size occur within the first order basins and contain third order basins, less than 10km in diameter, where the stratiform sulphide lenses tend to develop. There are several ideas for the formation of these deposits but one contention is that they were formed by the convection of sea water as shown above. As the sea water traverses through the crust it would dissolve base metals from the host rock, which would eventually lead to their collection and precipitation near the surface.
    [Show full text]
  • Depositional Setting of Algoma-Type Banded Iron Formation Blandine Gourcerol, P Thurston, D Kontak, O Côté-Mantha, J Biczok
    Depositional Setting of Algoma-type Banded Iron Formation Blandine Gourcerol, P Thurston, D Kontak, O Côté-Mantha, J Biczok To cite this version: Blandine Gourcerol, P Thurston, D Kontak, O Côté-Mantha, J Biczok. Depositional Setting of Algoma-type Banded Iron Formation. Precambrian Research, Elsevier, 2016. hal-02283951 HAL Id: hal-02283951 https://hal-brgm.archives-ouvertes.fr/hal-02283951 Submitted on 11 Sep 2019 HAL is a multi-disciplinary open access L’archive ouverte pluridisciplinaire HAL, est archive for the deposit and dissemination of sci- destinée au dépôt et à la diffusion de documents entific research documents, whether they are pub- scientifiques de niveau recherche, publiés ou non, lished or not. The documents may come from émanant des établissements d’enseignement et de teaching and research institutions in France or recherche français ou étrangers, des laboratoires abroad, or from public or private research centers. publics ou privés. Accepted Manuscript Depositional Setting of Algoma-type Banded Iron Formation B. Gourcerol, P.C. Thurston, D.J. Kontak, O. Côté-Mantha, J. Biczok PII: S0301-9268(16)30108-5 DOI: http://dx.doi.org/10.1016/j.precamres.2016.04.019 Reference: PRECAM 4501 To appear in: Precambrian Research Received Date: 26 September 2015 Revised Date: 21 January 2016 Accepted Date: 30 April 2016 Please cite this article as: B. Gourcerol, P.C. Thurston, D.J. Kontak, O. Côté-Mantha, J. Biczok, Depositional Setting of Algoma-type Banded Iron Formation, Precambrian Research (2016), doi: http://dx.doi.org/10.1016/j.precamres. 2016.04.019 This is a PDF file of an unedited manuscript that has been accepted for publication.
    [Show full text]
  • Tungsten Ore Concentrates from the People's Republic of China
    TUNGSTEN ORE CONCENTRATES FROM THE PEOPLE'S REPUBLIC OF CHINA Determination of the Commission in Investigation No. 731—TA-497 (Preliminary) Under the Tariff Act of 1930, Together With the Information Obtained in the Investigation USITC PUBLICATION 2367 MARCH 1991 United States International Trade Commission Washington, DC 20436 UNITED STATES INTERNATIONAL TRADE COMMISSION COMMISSIONERS Anne E. Brunsdale, Acting Chairman Seeley G. Lodwick David B. Rohr Don E. Newquist Charles Ervin, Director of Operations Staff assigned: Mary Trimble, Investigator Jeffrey Anspacher, Economist Vincent DeSapio, Industry Analyst Marshall Wade, Accountant/Financial Analyst Craig McKee, Attorney George Deyman, Supervisory Investigator Address all communications to Kenneth R. Mason, Secretary to the Commission United States International Trade Commission Washington, DC 20436 CONTENTS Page Determination 1 Views of the Commission 3 Information obtained in the investigation A-1 Introduction A-1 The product A-2 Description and uses A-2 Manufacturing process A-3 Substitute products A-4 U.S. tariff treatment A-4 The nature and extent of alleged sales at LTFV A-5 The world market A-5 The U.S. market A-7 Apparent U.S. consumption A-7 U.S. producers A-9 Curtis Tungsten, Inc A-9 U.S. Tungsten Corp A-11 U.S. importers A-11 U.S. traders/brokers A-12 U.S. consumers of imported tungsten ore concentrates A-12 U.S. Government stockpiles A-13 Toll production A-13 Channels of distribution A-13 Consideration of alleged material injury A-14 U.S. production, capacity, and capacity utilization A-14 U.S. producers' U.S. shipments (commercial and captive) and export shipments A-17 Commercial U.S.
    [Show full text]
  • The Efficient Improvement of Original Magnetite in Iron Ore Reduction
    minerals Article The Efficient Improvement of Original Magnetite in Iron Ore Reduction Reaction in Magnetization Roasting Process and Mechanism Analysis by In Situ and Continuous Image Capture Bing Zhao 1,2, Peng Gao 1,2,*, Zhidong Tang 1,2 and Wuzhi Zhang 1,2 1 School of Resources and Civil Engineering, Northeastern University, Shenyang 110819, China; [email protected] (B.Z.); [email protected] (Z.T.); [email protected] (W.Z.) 2 National-Local Joint Engineering Research Center of High-Efficient Exploitation Technology for Refractory Iron Ore Resources, Shenyang 110819, China * Correspondence: [email protected]; Tel.: +86-024-8368-8920 Abstract: Magnetization roasting followed by magnetic separation is considered an effective method for recovering iron minerals. As hematite and magnetite are the main concomitant constituents in iron ores, the separation index after the magnetization roasting will be more optimized than with only hematite. In this research, the mechanism of the original magnetite improving iron ore reduction during the magnetization roasting process was explored using ore fines and lump ore samples. Under optimum roasting conditions, the iron grade increased from 62.17% to 65.22%, and iron recovery increased from 84.02% to 92.02% after separation, when Fe in the original magnetite content increased from 0.31% to 8.09%, although the Fe masses in each sample were equal. For lump ores with magnetite and hematite intergrowth, the method of in situ and continuous image capture Citation: Zhao, B.; Gao, P.; Tang, Z.; for microcrack generation and the evolution of the magnetization roasting process was innovatively Zhang, W.
    [Show full text]
  • Recovery of Magnetite-Hematite Concentrate from Iron Ore Tailings
    E3S Web of Conferences 247, 01042 (2021) https://doi.org/10.1051/e3sconf/202124701042 ICEPP-2021 Recovery of magnetite-hematite concentrate from iron ore tailings Mikhail Khokhulya1,*, Alexander Fomin1, and Svetlana Alekseeva1 1Mining Institute of Kola Science Center of Russian Academy of Sciences, Apatity, 184209, Russia Abstract. The research is aimed at study of the probable recovery of iron from the tailings of the Olcon mining company located in the north-western Arctic zone of Russia. Material composition of a sample from a tailings dump was analysed. The authors have developed a separation production technology to recover magnetite-hematite concentrate from the tailings. A processing flowsheet includes magnetic separation, milling and gravity concentration methods. The separation technology provides for production of iron ore concentrate with total iron content of 65.9% and recovers 91.0% of magnetite and 80.5% of hematite from the tailings containing 20.4% of total iron. The proposed technology will increase production of the concentrate at a dressing plant and reduce environmental impact. 1 Introduction The mineral processing plant of the Olcon JSC, located at the Murmansk region, produces magnetite- At present, there is an important problem worldwide in hematite concentrate. The processing technology the disposal of waste generated during the mineral includes several magnetic separation stages to produce production and processing. Tailings dumps occupy huge magnetite concentrate and two jigging stages to produce areas and pollute the environment. However, waste hematite concentrate from a non-magnetic fraction of material contains some valuable components that can be magnetic separation [13]. used in various industries. In the initial period of plant operation (since 1955) In Russia, mining-induced waste occupies more than iron ore tailings were stored in the Southern Bay of 300 thousand hectares of lands.
    [Show full text]
  • Standard Reference Materials
    MBS 0F STAND PUBLICATIONS iffiJIimTk & TECH IIIIIII A 11 10 7 E57&&y NBS SPECIAL PUBLICATION 260-97 /?e AU o* U.S. DEPARTMENT OF COMMERCE/National Bureau of Standards Standard Reference Materials: Summary of the Coal, Ore, Mineral, Rock, and Refractory Standards Issued by the National Bureau of Standards 100 Radu Mavrodineanu and Thomas E. Gills • U57 260-97 1985 c2 . Tm he National Bureau of Standards was established by an act of Congress on March 3, 1901. The m Bureau's overall goal is to strengthen and advance the nation's science and technology and facilitate their effective application for public benefit. To this end, the Bureau conducts research and provides: (1) a basis for the nation's physical measurement system, (2) scientific and technological services for industry and government, (3) a technical basis for equity in trade, and (4) technical services to promote public safety. The Bureau's technical work is performed by the National Measurement Laboratory, the National Engineering Laboratory, the Institute for Computer Sciences and Technology, and the Institute for Materials Science and Engineering The National Measurement Laboratory 2 Provides the national system of physical and chemical measurement; • Basic Standards coordinates the system with measurement systems of other nations and • Radiation Research furnishes essential services leading to accurate and uniform physical and • Chemical Physics chemical measurement throughout the Nation's scientific community, in- • Analytical Chemistry dustry, and commerce; provides advisory
    [Show full text]
  • Banded Iron Formations
    Banded Iron Formations Cover Slide 1 What are Banded Iron Formations (BIFs)? • Large sedimentary structures Kalmina gorge banded iron (Gypsy Denise 2013, Creative Commons) BIFs were deposited in shallow marine troughs or basins. Deposits are tens of km long, several km wide and 150 – 600 m thick. Photo is of Kalmina gorge in the Pilbara (Karijini National Park, Hamersley Ranges) 2 What are Banded Iron Formations (BIFs)? • Large sedimentary structures • Bands of iron rich and iron poor rock Iron rich bands: hematite (Fe2O3), magnetite (Fe3O4), siderite (FeCO3) or pyrite (FeS2). Iron poor bands: chert (fine‐grained quartz) and low iron oxide levels Rock sample from a BIF (Woudloper 2009, Creative Commons 1.0) Iron rich bands are composed of hematitie (Fe2O3), magnetite (Fe3O4), siderite (FeCO3) or pyrite (FeS2). The iron poor bands contain chert (fine‐grained quartz) with lesser amounts of iron oxide. 3 What are Banded Iron Formations (BIFs)? • Large sedimentary structures • Bands of iron rich and iron poor rock • Archaean and Proterozoic in age BIF formation through time (KG Budge 2020, public domain) BIFs were deposited for 2 billion years during the Archaean and Proterozoic. There was another short time of deposition during a Snowball Earth event. 4 Why are BIFs important? • Iron ore exports are Australia’s top earner, worth $61 billion in 2017‐2018 • Iron ore comes from enriched BIF deposits Rio Tinto iron ore shiploader in the Pilbara (C Hargrave, CSIRO Science Image) Australia is consistently the leading iron ore exporter in the world. We have large deposits where the iron‐poor chert bands have been leached away, leaving 40%‐60% iron.
    [Show full text]
  • Smelting Iron from Laterite: Technical Possibility Or Ethnographic Aberration?
    Smelting Iron from Laterite: Technical Possibility or Ethnographic Aberration? T. O. PRYCE AND S. NATAPINTU introduction Laterites deposits (orlateriticsoilsastheyarealsocalled)arefrequently reported in Southeast Asia, and are ethnographically attested to have been used for the smelting of iron in the region (Abendanon 1917 in Bronson 1992:73; Bronson and Charoenwongsa 1986), as well as in Africa (Gordon and Killick 1993; Miller and Van Der Merwe 1994). The present authors do not dispute this evidence; we merely wish to counsel cautioninitsextrapolation.Modifyingour understanding of a population’s potential to locally produce their own iron has immediate ramifications for how we reconstruct ancient metal distribution net- works, and the social exchanges that have facilitated them since iron’s generally agreed appearance in Southeast Asian archaeological contexts during the mid-first millennium b.c. (e.g., Bellwood 2007:268; Higham 1989:190). We present this paper as a wholly constructive critique of what appears to be a prevailingperspectiveonpre-modernSoutheastAsianironmetallurgy.Wehave tried to avoid technical language and jargon wherever possible, as our aim is to motivate scholars working within the regiontogivefurtherconsiderationtoiron as a metal, as a technology, and as a socially significant medium (e.g., Appadurai 1998; Binsbergen 2005; Gosden and Marshall 1999). When writing a critique it is of course necessary to cite researchers with whom one disagrees, and we have done this with full acknowledgment that in modern archaeology no one person can encompass the entire knowledge spectrum of the discipline.1 The archaeome- tallurgy of iron is probably on the periphery of most of our colleagues’ interests, but sometimes, within the technical, lies the pivotal, and in sharing some of our insights we hope to illuminate issues of benefit to all researchers in Metal Age Southeast Asia.
    [Show full text]
  • Some Ore Textures Involving Sphalerite from the Furutobe Mine, Akita Prefecture, Japan*
    MINING GEOLOGY, 28, 293•`300, 1978 Some Ore Textures Involving Sphalerite from the Furutobe Mine, Akita Prefecture, Japan* Paul B. BARTON,Jr.** Abstract: Observations of doubly-polished, uncovered thin sections of Kuroko from Furutobe reveal a paragenesis of great complexity. Sphalerite crystals up to 2 mm across show finely detailed growth banding, and the crystals occur both as broken fragments in "moved" ore and as later fillings between clasts. The "moved" ore exhibits a variety of sphalerite types (including coarse crystals as well as fine-grained aggregates) as clasts showing that coarse crystals did exist prior to the synsedimentary slumping. Growth of large crystals seems incompatible with rapid deposition on the sea floor, therefore an alternative model is suggested. The initial deposits were derived from submarine hot springs and consisted of very fine-grained sulfides with silica and barite. With con- tinued supply of hot fluid the lower part of the sulfide deposit covering the vent became heated, and solution and reprecipitation occurred below an upper, less permeable "blanket." Deposits formed on slopes slumped repeatedly yielding graded beds with coarse sphalerite and other sulfides incorporated in a melange of finer ore and gangue fragments. Much of the sphalerite exhibits a fine "dusting" of chalcopyrite that appears to have developed subsequent to the growth of the host sphalerite, probably by a process of replacement, not of exsolution. revealed in my small collection , are startling Introduction and, even more surprising, apparently have not In recent years the Miocene Kuroko deposits been described in the voluminous and other- of Japan have become recognized almost wise comprehensive Japanese literature.
    [Show full text]
  • Extraction of Lead from Galena Concentrates Using Fluosilicic Acid and Peroxide
    View metadata, citation and similar papers at core.ac.uk brought to you by CORE provided by Jurnal Puslitbang tekMira (Teknologi Mineral dan Batubara) INDONESIAN MINING JOURNAL Vol. 20, No. 1, April 2017 : 69 - 80 EXTRACTION OF LEAD FROM GALENA CONCENTRATES USING FLUOSILICIC ACID AND PEROXIDE EKSTRAKSI TIMBAL DARI KONSENTRAT GALENA MENGGUNAKAN ASAM FLUOSILIKAT DAN PEROKSIDA DESSY AMALIA, YUNITA RAMANDA and MARYONO Research & Development Centre for Mineral and Coal Technology Jalan Jenderal Sudirman 623 Bandung 40211 Ph. (+6222) 6030483, Fax. (+6222) 6003373 e-mail: [email protected] ABSTRACT A study on lead extraction from lead concentrate had been conducted. Galena is usually associated with other sulfide ores such as sphalerite.The lead concentrate was able to be extracted and purified into its metal through a leaching process using a selective solvent of fluosilicic acid (H2SiF6). Parameters used in this process include ratio (dose) of reactant (H2SiF6:H2O2), temperature (without heating; 30; 50; 70; 80; and 90°C) and particle size (-100+150#, -150+200#, -200+325, dan -325#).The best extraction was achieved using the particle size of -325 mesh. The amount of extracted lead was increased due to the rise of temperature and dose of fluosilicic. The amount of peroxide addition was determined by its optimum influence on the lead extraction because its excess would produce PbSO4. The influence of H2SiF6 and H2O2 doses was calculated using ANOVA. Keywords: galena, leaching, fluosilicic acid, peroxide, precipitation. ABSTRAK Pemrosesan konsentrat Pb telah dilakukan untuk memperoleh logamnya. Galena pada umumnya berasosiasi dengan mineral sulfida lainnya seperti sphalerit. Konsentrat tersebut dapat diekstraksi dan dimurnikan untuk memperoleh logam melalui proses pelindian menggunakan pelarut selektif seperti asam fluosilikat (H2SiF6).
    [Show full text]