Materials Week '97: Monday AM Session

Focusing on physical metallurgy and materials, Materials Week '97, which incorporates the TMS Fall Meeting, features a wide array of technical symposia sponsored by The Minerals, Metals & Materials Society (TMS) and ASM International. The meeting will be held September 14-18 in Indianapolis, Indiana. The following session will be held Monday morning, September 15.

TITANIUM EXTRACTION AND PROCESSING: Session I: Titanium Recovery Processes

Sponsored by: LMD Reactive Metals Committee

Program Organizers: B. Mishra, Dept. of Metall. & Matls. Eng., Colorado School of Mines, Golden, CO 80401; G.J. Kipouros, Dept. of Mining & Metall. Engg., Technical Univ. of Nova Scotia, Halifax, Nova Scotia, Canada B3J2X4; J. Monsees, International Titanium Association, 1871 Folsom St., Suite #100, Boulder, CO 80302; S. Daniel, Oremet Titanium, 530 W. 34th Avenue, P.O. Box 580, Albany, OR 97321

Room: 203

Session Chairs: Dr. B. Mishra, Department of Metallurgical & Materials Engineering, Colorado School of Mines, Golden, CO 80401; Mr. S. Daniel, Oremet Titanium, 530 W. 34th Avenue, P.O. Box 580, Albany, OR 97321

HIGH PURITY TITANIUM REFINING BY IODIDE PURIFICATION: R.K.F. Lam, Materials Research Corporation, Advanced Materials Division, 542 Route 303, Orangeburg, NY 10962

An improved iodide process has been developed to purify titanium metal to high purity. The process consists of (1) in-situ generation of titanium tetraiodide from crude titanium, (2) purification of titanium tetraiodide by distillation, and (3) decomposition of purified titanium tetraiodide to high purity titanium metal. Purity level of titanium metal is increased from 99.5% to 99.998%. Titanium tetraiodide is purified to 99.999% purity. Thermodynamic properties of titanium tetraiodide and impurity iodides are discussed. Properties of refined titanium metal and titanium tetraiodide are investigated. Automatic control was employed for maintaining reactor temperatures, chamber pressures, and electric power levels for heating up deposition surfaces. Experimental data and purity levels are compared with those reported by other researchers.

9:10 am

RECOVERY OF TITANIUM FROM BLAST FURNACE SLAGS: Z. Sui, N. Fu, Y. Zhang, School of Materials and Metallurgy, Northeastern University, Shenyang 110006, China

China bounds in mineral resources of iron, but some of that are composite mineral ores containing valuable nonferrous metals components such as Ti-V bearing magnetite ore in Southwest part China-Panzhihua. Due to complex mineralogy, very fine mineral dissemination and low grade, the Titanium Components were mostly concentrated in molten slags and separated from liquid pig -iron, when the ore was usually treated in Blast-furnace. So slags contained titanium became an important man-made resources, from that the titanium components could be recovered by the technique based on the precipitation selectivity. It was indicated by a series of experiments that the recovery efficiency of titanium components from the slags was directly related to the proper precipitating feature of Titanium component in the cooled slags, such as morphology, structure, phase composition, crystallized state, grain size and dispersity, which were obviously depended on the operation factors like the slags composition, temperature of heat-treatment, cooling rate and additive agent. Based on the optimum factors, the precipitating behavior of Titanium component from the slags could be artificially controlled by designing the operation conditions, which were investigated by a technique of TEM observation in situ of heating sample and then the thermodynamic analysis and the computer simulation combined with fractal description as auxiliary. The selective precipitation of Titanium bearing slags was studied as example, by which both available research method for studying on the precipitating selectivity of Boron and Rare Earth metals components from slags were also summarized.

9:35 am

SPECIATION OF TITANIUM DURING AND AFTER PROCESSING OF TUNGSTEN CARBIDE SCRAP FOR TUNGSTEN AND COBALT: R.P. Singh, M.J. Miller, Chemical Development Department, R&D Division, Chemical & Metallurgical Products, Osram Sylvania, Inc., Hawes Street, Towanda, PA 18848-0504

Tungsten carbide scarp contains 1 to 2 % titanium. At present during hydrometallurgical processing of tungsten carbide scrap, the recovery of titanium is not considered economically viable. However, strict environmental regulations and/or diminishing titanium sources may change all that in future. This paper would discuss the speciation of titanium during and after processing of tungsten carbide scarp for tungsten and cobalt recovery. Complete characterization of titanium-containing species, which is of fundamental importance in the development of extraction and processing methods of titanium recovery from tungsten carbide scrap, will be reported.

10:00 am BREAK

10:15 am

TITANIUM & TITANIUM ALLOYS RESEARCH AT THE INSTITUTE FOR NON-FERROUS AND RARE METALS, BUCHAREST, ROMANIA: T. Segaroeanu, Gh. Busila, V. Secanu, Gh. Morcan, L. Dumitru, St. Ivanescu, S. Dinescu, D. Capac, Institute for Non-Ferrous and Rare Metals, Bd. Biruintel 102, Sector 2, Bucharest, Romania

The research work performed within the Institute for Non-ferrous and Rare Metals of Bucharest, Romania was focused on the development of technologies for obtaining titanium from domestic raw materials, producing different titanium alloys and, also, on turning of the titanium and titanium alloys in to semi-finished products. For the titanium industry, we have produced complete technologies to process titanium slags through chlorination, purification and magnesiothermic reduction of the titanium chloride. Titanium and titanium alloys ingots were obtained by electron beam melting and by consumable electrode arc melting of the titanium sponge and pre-alloyed materials. Our research has continued with the processing of these ingots in rods, sheets, tubes, wires, and cast products. According to the Romanian industry needs, the research work in the field of titanium and titanium alloys was directed to the applications for medical use, chemical industry, naval applications and aircraft buildings. At the same time, we have developed titanium metal scrap processing technologies through molten salt electrolysis and we have obtained titanium metal powders. We have, also, obtained titanium metal powders via a hydrogenation-dehydrogenation process. Recently, our Institute has developed research programs in the areas of new corrosion resistant titanium alloys, intermetallic compounds and titanium-matrix composites.

10:40 am

THE CHEMICAL BASIS OF A NOVEL FLUORIDE ROUTE TO METALLIC TITANIUM: J. Besida, T.A. O'Donnell, T.K. Pong, D.G. Wood, Department of Chemical Engineering, University of Melbourne, Parkville, Victoria 3052, Australia

The conventional route to metallic titanium, the Kroll Process, involves reduction of TiCl₄ with magnesium and produces a sponge which is difficult to recover and is heavily contaminated with reaction products and excess reactant. After recovery, the sponge requires very costly vacuum arc refining to produce useable billets. Some earlier proposed fluoride routes also lead to sponge formation. In the present work K₂TiF₆, which unlike TiCl₄ is not air-or moisture-sensitive, is dissolved in molten cryolite, and has been shown at gram-scale experimental level to be reduced by metallic Al to produce a powder of metallic Ti which is about 99% pure and can be recovered as a free-flowing product. NaF is added in stoichiometric amount during the reaction to preserve the integrity of the liquid cryolite medium according to the overall equation: 3Na₂TiF₆ + 4A1 + 6NaF ~ 4Na₃AlF₆ + 3Ti.

11:05 am

CONTINUOUS PRODUCTION OF TITANIUM POWDER: S.J. Gerdemann, L.L. Oden, J.C. White, Department of Energy, Albany Research Center, 1450 Queen Avenue, S.W., Albany, OR 97321-2198

Although incremental improvements have been made to the Kroll process since its inception in 1948, the process in use today remains essentially the same batch process developed by Dr. Kroll and perfected by the U. S. Bureau of Mines. In this process, titanium tetrachloride (TiCl₄) is reduced by magnesium to produce titanium metal. There are two major limitations to the Kroll process: 1) it is a batch process and 2) the titanium sponge produced must undergo several purification steps before the metal is suitable for use. During the reduction of TiCl₄ with either magnesium (Kroll process) or sodium (Hunter process) the reaction proceeds so rapidly that the titanium metal sponge formed is an interlocking dendritic mass with inclusions of magnesium or sodium salts. The Albany Research Center (ALRC) is investigating a new, continuous titanium metal production process in which a titanium powder is produced in a bath of molten salt. In this process the rate of the reduction reaction is slowed and controlled by diluting the reactants with molten chloride salts. The diluted reactant streams are combined in a continuous stirred tank reactor, operated much like a crystallizer. New titanium metal forms on the already present small Ti particles and when the Ti particles become so large that they can no longer be suspended in solution, they fall to the bottom of the reactor and are removed. Initial experiments show considerable promise but problems remain in obtaining the purity and uniform particle size required.