DOCSLIB.ORG

US2257978.Pdf

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
US2257978.Pdf Oct 7, 1941-‘ J. ROBERTSON Ei- AL 2,257,978 EXTRACTION OF VANADIUM VALiIES FV‘ROM VANADIUM-BEARING MATERIAL Filed Feb. 25, 1940 s She'ets-Sheét 2. EFF EC 7" 01- 7'EMPERA TU/i’t' OF ?'oAsr HEADS- 20 MESH DRY Gnau/vo H0146? 90 Mm ‘ . CALC/NES QUE/VCHED 11v WATER SEC‘IONDARY Gm/vn / . a0. - " , ' . _ ' ‘ légTor/u. DI-SSOLVED 10 I 1000 1100 1200 1300 1400 1500 1600 1700 1000 IQVENTOR ?’oAsr TEMPERATUREjDEG'REES E Jahn ?abertqan ArcizibaZdAlexandenSjvrauZ?olberi'farl Dunn = _' ?rmmw?m Patented Oct. 7, 1941 22,257,978 UNITED STATES PATENT o-FFiicE EXTRACTION OF VANADIUM VALUES FROM VANADIUM-BEARING MATERIAL . John Robertson, Ricran, Peru,_'Holber't Earl Dunn, Grafton, Pa., and Archibald Alexander ‘Sproul, Rye, N. Y., assignors to Vanadium‘ Corporation of America, Bridgevill e, Pa., a corporation of Delaware Application February .23, 1940, Serial‘No. 320,458 16 Claims. (01.23-18) This invention relates to a process for recover adding transposing agents, provided that the ing vanadium values from ores and other vana roast is carried out at the proper temperature dium-bearing materials. The term vanadium and 'using the proper temperature-time cycle values is used as a. generic expression to include both for the heating and cooling operation. In the vanadium recovered whether as vanadium or respect to ‘the latter, a further, condition is that as a. compound existing in the ore or as a com the roasted ore must be cooled at a su?liciently pound synthesized from the ore. rapid rate, in order not to permit the soluble cal This application is a continuation-in-part of cium vanadate formed during the roasting to be our co-pending application, Serial No. 221,610, converted to any appreciable extent into apwater ?led July 2'7, 1938,'which application is a contin insoluble form. We have found that different uation-in-part .of our application, Serial No. vanadium ores behave diiferently in these roast’ 87,784, ?led June 27, 1936. ing and cooling operations and that ‘there exists The present invention provides a process for not only an optimumtemperature ‘and time cycle . recovering vanadium, values from ores or other during the heating or roasting stage but also a vanadium-bearing materials which is less costly critical cooling rate in the ?nal cooling stage, and in which the recovery is more nearly com which critical cooling 'rate must be exceeded, in plete than in the methods heretofore employed. order to prevent retransformation of the soluble It eliminates the use of ?uxing or transposing vanadate to an insoluble vanadate. agents during the roast-and the roast is so car We have found that when an ore containing ried out that a large proportion'of the vanadium - compounds of vanadium and calcium is roasted content is rendered water soluble, thus ‘enabling at different temperatures, a series of calcium the use of ‘a water quench in place of an acid or vanadates are formed, some of which are water alkaline leach. The water quench is, however, insoluble'and others of which are water soluble. followed by an acid leach to extract further por Thus, at a roasting temperature between about tions of vanadium. 1000° F. and l200° F. the water insoluble calcium In the accompanying drawings: ortho-vanadate is formed. Therefore, if such Fig. 1 is a ?ow sheet illustrating the preferred roasting temperatures are employed, it is neces manner of carrying out the process; sary to ‘employ a transposihg agent such as so Fig. 2 is a chart illustrating the solubility se-V dium chloride, sodium-sulphate or sodium car-" cured by quenching at the roasting temperature; bonate'in the roast, in order to Tender the'roast and water soluble. ' Fig. 3 is arsimilar chart illustrating the solu 'It is well -recogni'ze'd'by those skilled in the bilities when the ore is allowed to ?rst cool in art of “extracting metals from ores that within air before quenching. a given type the Iche‘micalcomposition, particu The most common method of recovering vana 35 larly with respect to major vconstituents (the dium value from its ores consists essentially of metals that it is desired to extract) may be roasting the ore with a suitable fluxing or trans substantially uniform from lot to lot. Yet the‘ posing agent or agents which convert the vana minor constituents (principally gangue mate dium content into soluble form. Such transpos rials) may vary widely without appearing. to al ing agents may be salt or soda ash, or both, ‘or ter the general characteristics of the ore; never other suitable material. The roasted ore is there thele‘ss, there is often apparent failure of a par after leached with water. The vanadium-bear ticular procedure to extract theabove mentioned ing liquor is ?ltered off and the vanadium con major constituentsuntil.some disturbingv feature tent is precipitated from this liquor by the addi-~ which may be a differenceprincipally of physical tion of the required amount of sulphuric acid. character has been vbrought ‘under control. In The cost of the transposing agent addedto the line with this generally accepted phenomena, we roast constitutes a large item of expense which is have found in studying vanadium ores that in the eliminated in our process. Furthermore, in our formation during roasting of the maximum process the amount of acid required is consider amount of soluble calcium vanadate the optimum ably reduced. temperature-time cycle varies somewhat with the We have found that normally water insoluble particular type‘of ore and the particular lot v‘of vanadium compounds in ores or other material any type being treated. There is, therefore, a which contain vanadium and compounds of cal necessary range ofgoperating conditions required cium or other alkaline earthmetals may be to satisfactorily ‘carry out our process with the rendered water soluble Without the necessity of '55 various ores to which it is applicable, in order to 2,257,978 . ._ .. _ _ , 2. - - . secure maximum extraction. In every case, how tals are believed to be calcium deuterotetra ever, the treatment involved is a roasting to con vanadate. vert vanadium present in the ore into soluble cal— If the roast is carried out at too low a tem cium or alkaline earth metal vanadate and then perature, or at too high a temperature, and is by cooling more quickly than the afore-mentioned immediately quenched in water, the water solu critical rate to effectively preserve the water sol ble calcium vanadate is not formed. If a roast uble vanadate and prevent its transformation ing temperature above 2000° F. is employed on into the insoluble calcium vanadate stable at the ore previously described, and the roasted room temperature that would result from slow ore is then immediately quenched in water and cooling. The soluble calcium vanadate is there 10 the quench liquor is concentrated so as to form after extracted with water and any remaining va crystals, we obtain green crystals which analyze: nadium is extracted by acid leaching, thus re Percent sulting as heretofore noted in a considerable V205 _________________________________ __ 59.30 saving in acid consumption, Water cooling ap CaO _________________________________ __ 17.69 pears to be more rapid for all ores than this 15 H2O (Loss on ignition) ________________ __ 23.35 critical cooling rate and hence two operations may be combined by quenching in water as here which correspond to the formula after described. 7 The initial stage of the roasting operation pref erably is carried out at some temperature above 20 CaVzOaAI-IzO 12000 F. This temperature is generally between and are practically insoluble in water, requiring 1400° F. and 1800° F., preferably about 1600° F., 35% or stronger sulphuric acid to dissolve them. but may go up as high as 20000 F. or‘ even higher, Upon reroasting the crystals at 1600° F. and if the maximum temperature and time cycle are quenching, they readily dissolve in water. not su?icient to cause appreciable sintering of 2.3 The process according to the present inven the material. Subsequent to the initial heating, the temperature may be lowered slowly or rapidly tion, may be carried out as follows: The ore crushed or comminuted to the desired ?neness, to some temperature not below about 1000” F. say 20 mesh, is roasted in a suitable furnace at before the rapid cooling at a rate greater than the the desired temperature, usually between about above noted critical cooling rate needs to be car 30 ried out. The temperature-time cycle produc 1400° F. and 1700" F., depending upon the type of ore or other material which is being treated.’ tive of maximum water extraction or maximum The roasted ore while being maintained at or total extraction by leaching in water and sub sequent leaching in acid will vary with different near the temperature of the roast is quenched ores and the process envisages the adjustment 3:3 in water. The quenched ore is then ground to of this temperature-time cycle in accordance with the desired degree of ?neness with the water. The ground material is ?ltered yielding a ?ltrate the needs of each case. containing a large proportion of the vanadium As an example, a characteristic ore treated in accordance with the present invention had the originally contained in the ore, hereafter called following composition: 40 “quench liquor,” and a residue hereafter called Percent “quench residue.” A leach of the quench resi due is then made with a dilute sulphuric acid V ____________________________________ __ 3.54 solution, say a 4% solution, and the leached ma CaO _________________________________ __ 15.53 terial is ?ltered yielding a ?ltrate hereafter S03 __________________________________ __ 25.91 - called “acid liquor” containing an additional A1203 ________________________________ __ 11.18 proportion of the vanadium contained in the SiOz _________________________________ __ 24.44 ore, and a ?nal residue or tailing.
Load more

Recommended publications
  • Aluminum-Vanadium System Donald Joseph Kenney Iowa State College
    Iowa State University Capstones, Theses and Retrospective Theses and Dissertations Dissertations 1953 Aluminum-vanadium system Donald Joseph Kenney Iowa State College Follow this and additional works at: https://lib.dr.iastate.edu/rtd Part of the Physical Chemistry Commons Recommended Citation Kenney, Donald Joseph, "Aluminum-vanadium system " (1953). Retrospective Theses and Dissertations. 13302. https://lib.dr.iastate.edu/rtd/13302 This Dissertation is brought to you for free and open access by the Iowa State University Capstones, Theses and Dissertations at Iowa State University Digital Repository. It has been accepted for inclusion in Retrospective Theses and Dissertations by an authorized administrator of Iowa State University Digital Repository. For more information, please contact [email protected]. NOTE TO USERS This reproduction is the best copy available. UMI mmMm-immim STSTEM BmaM S, Ktrmey A Mssertattioa aibaitted to the Sradttate Paeulty in fsKptial Fulfillffleat of the l®cpiir«a®ats tor the Degree of eocfoa or piiLosoFif Sabjecti aysiefil CheBdstry ^proved f Signature was redacted for privacy. In C2iarg®;!6f Ifejor Work Signature was redacted for privacy. Signature was redacted for privacy. Iowa State College 1953 UMI Number: DP12420 INFORMATION TO USERS The quality of this reproduction is dependent upon the quality of the copy submitted. Broken or indistinct print, colored or poor quality illustrations and photographs, print bleed-through, substandard margins, and improper alignment can adversely affect reproduction. In the unlikely event that the author did not send a complete manuscript and there are missing pages, these will be noted. Also, if unauthorized copyright material had to be removed, a note will indicate the deletion.
    [Show full text]
  • Toxicological Profile for Vanadium
    VANADIUM 107 4. CHEMICAL AND PHYSICAL INFORMATION 4.1 CHEMICAL IDENTITY Vanadium is a naturally occurring element that appears in group 5(B5) of the periodic table (Lide 2008). Vanadium is widely distributed in the earth’s crust at an average concentration of 100 ppm nd (approximately 100 mg/kg), similar to that of zinc and nickel (Byerrum 1991). Vanadium is the 22 most abundant element in the earth’s crust (Baroch 2006). Vanadium is found in about 65 different minerals; carnotite, roscoelite, vanadinite, and patronite are important sources of this metal along with bravoite and davidite (Baroch 2006, Lide 2008). It is also found in phosphate rock and certain ores and is present in some crude oils as organic complexes (Lide 2008). Table 4-1 lists common synonyms and other pertinent identification information for vanadium and representative vanadium compounds. 4.2 PHYSICAL AND CHEMICAL PROPERTIES Vanadium is a gray metal with a body-centered cubic crystal system. It is a member of the first transition series. Because of its high melting point, it is referred to as a refractory metal (Baroch 2006). When highly pure, it is a bright white metal that is soft and ductile. It has good structural strength and a low- fission neutron cross section. Vanadium has good corrosion resistance to alkalis, sulfuric and hydrochloric acid, and salt water; however, the metal oxidizes readily above 660 °C (Lide 2008). The chemistry of vanadium compounds is related to the oxidation state of the vanadium (Woolery 2005). Vanadium has oxidation states of +2, +3, +4, and +5. When heated in air at different temperatures, it oxidizes to a brownish black trioxide, a blue black tetraoxide, or a reddish orange pentoxide.
    [Show full text]
  • Effect of the Vanadium Addition on the Grain Size and Mechanical Properties of the Copper-Aluminium-Zinc Shape Memory Alloys K
    EFFECT OF THE VANADIUM ADDITION ON THE GRAIN SIZE AND MECHANICAL PROPERTIES OF THE COPPER-ALUMINIUM-ZINC SHAPE MEMORY ALLOYS K. Enami, N. Takimoto, S. Nenno To cite this version: K. Enami, N. Takimoto, S. Nenno. EFFECT OF THE VANADIUM ADDITION ON THE GRAIN SIZE AND MECHANICAL PROPERTIES OF THE COPPER-ALUMINIUM-ZINC SHAPE MEMORY ALLOYS. Journal de Physique Colloques, 1982, 43 (C4), pp.C4-773-C4-778. 10.1051/jphyscol:19824126. jpa-00222109 HAL Id: jpa-00222109 https://hal.archives-ouvertes.fr/jpa-00222109 Submitted on 1 Jan 1982 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. JOURNAL DE PHYSIQUE Colloque C4, suppl&nent au no 12, Tome 43, dbcembre 1982 page C4-773 EFFECT OF THE VANADIUM ADDITION ON THE GRAIN SIZE AND MECHANICAL PROPERTIES OF THE COPPER-ALUMINIUM-ZINC SHAPE MEMORY ALLOYS K. Enami, N. Takimoto and S. Nenno Department of Materials Science and Engineering, Osaka University, Suita, Osaka, Japan (Revised text accepted 27 September 1982) Abstract. - The effects of vanadium addition on the 0-grain size, pseudo- elastic and shape memory behaviour and fracture mode of the copper-aluminium- zinc shape memory alloys with different vanadium contents were investigated.
    [Show full text]
  • 169 a NEW IRON/VANADIUM (FE/V) REDOX FLOW BATTERY Liyu Li
    A NEW IRON/VANADIUM (FE/V) REDOX FLOW BATTERY Liyu Li, Wei Wang, Zimin Nie, Baowei Chen, Feng Chen, Qingtao Luo, Soowhan Kim, and Gary Z Yang Pacific Northwest National Laboratory, P.O. Box 999, Richland, WA, USA ABSTRACT A novel redox flow battery using Fe2+/Fe3+ and V2+/V3+ redox couples in chloride supporting electrolyte and in chloric/sulfuric mixed-acid supporting electrolyte was investigated for potential stationary energy storage applications. The iron/vanadium (Fe/V) redox flow cell using mixed reactant solutions operated within a voltage window of 0.5~1.35 volts with a nearly 100% utilization ratio and demonstrated stable cycling over 100 cycles with energy efficiency > 80% and almost no capacity fading. Stable performance was achieved in the temperature range between 0 °C and 50 °C. Unlike the iron/chromium (Fe/Cr) redox flow battery that operates at an elevated temperature of 65 °C, the necessity of external heat management is eliminated. The improved electrochemical performance makes the Fe/V redox flow battery a promising option as a stationary energy storage device to enable renewable integration and stabilization of the electric grid. Keywords: redox flow battery, hydrochloric acid, sulfuric acid, Fe/V, mixed acid, energy storage INTRODUCTION energy loss and significantly increases the overall operating cost [3]. Redox flow batteries (RFBs) are electrochemical devices that store electrical energy In our work, we proposed and investigated the in liquid electrolytes [1]. The energy conversion electrochemical performance of a new RFB that between chemical energy and electricity energy is employs a V2+/V 3+ solution anolyte and a Fe2+/Fe 3+ carried out as liquid electrolytes flow through cell solution catholyte or a mixed solution as both the stacks.
    [Show full text]
  • Investigation of the Alkali-Metal Vanadium Oxide Xerogel Bronzes: &V205mh20 (A = K and Cs) Y.-J
    1616 Chem. Mater. 1995, 7, 1616-1624 Investigation of the Alkali-Metal Vanadium Oxide Xerogel Bronzes: &V205mH20 (A = K and Cs) Y.-J. Liu,tl# J. A. Cowen,**#T. A. &plan,$>$D. C. DeGroot,l J. Schindler,l C. R. &nnewurf,l and M. G. Kanatzidis*stT§ Department of Chemistry, Michigan State University, East Lansing, Michigan 48824; Department of Physics, Michigan State University, East Lansing, Michigan 48824; Center for Fundamental Materials Research, Michigan State University, East Lansing, Michigan 48824; and Department of Electrical Engineering and Computer Science, Northwestern University, Evanston, Illinois 60208 Received January 18, 1995. Revised Manuscript Received June 13, 1995@ The synthesis of bronze-like AXV205*nHz0xerogels (A = K and Cs, 0.05 x 0.6) and systematic characterization of their chemical, structural, spectroscopic magnetic, and charge- transport properties are reported. These materials were prepared by the reaction of V205-nHzO with various amounts of alkali iodide (KI and CSI) in acetone under Nz atmosphere for 3 days. X-ray diffraction and spectroscopic data indicate that the V2O5 framework in AZVz05*nH20maintains the pristine V205 xerogel structure. The increased V4+ (dl) concentration in the V205 framework causes the disappearance of EPR hyperfine structure and the increase of magnetic susceptibility and electrical conductivity. The optical diffuse reflectance spectra of these compounds show characteristic absorption bands due to inter-valence (V4+N5+)charge-transfer transitions. The magnetic behavior is best described as Curie- Weiss type coupled with temperature-independent paramagnetism (TIP). The Curie constant and EPR peak width of the &VsO~.nH20 materials show unusual behavior consistent with strong antiferromagnetic coupling of neighboring V4+centers.
    [Show full text]
  • BNL-79513-2007-CP Standard Atomic Weights Tables 2007 Abridged To
    BNL-79513-2007-CP Standard Atomic Weights Tables 2007 Abridged to Four and Five Significant Figures Norman E. Holden Energy Sciences & Technology Department National Nuclear Data Center Brookhaven National Laboratory P.O. Box 5000 Upton, NY 11973-5000 www.bnl.gov Prepared for the 44th IUPAC General Assembly, in Torino, Italy August 2007 Notice: This manuscript has been authored by employees of Brookhaven Science Associates, LLC under Contract No. DE-AC02-98CH10886 with the U.S. Department of Energy. The publisher by accepting the manuscript for publication acknowledges that the United States Government retains a non-exclusive, paid-up, irrevocable, world-wide license to publish or reproduce the published form of this manuscript, or allow others to do so, for United States Government purposes. This preprint is intended for publication in a journal or proceedings. Since changes may be made before publication, it may not be cited or reproduced without the author’s permission. DISCLAIMER This report was prepared as an account of work sponsored by an agency of the United States Government. Neither the United States Government nor any agency thereof, nor any of their employees, nor any of their contractors, subcontractors, or their employees, makes any warranty, express or implied, or assumes any legal liability or responsibility for the accuracy, completeness, or any third party’s use or the results of such use of any information, apparatus, product, or process disclosed, or represents that its use would not infringe privately owned rights. Reference herein to any specific commercial product, process, or service by trade name, trademark, manufacturer, or otherwise, does not necessarily constitute or imply its endorsement, recommendation, or favoring by the United States Government or any agency thereof or its contractors or subcontractors.
    [Show full text]
  • The Elements.Pdf
    A Periodic Table of the Elements at Los Alamos National Laboratory Los Alamos National Laboratory's Chemistry Division Presents Periodic Table of the Elements A Resource for Elementary, Middle School, and High School Students Click an element for more information: Group** Period 1 18 IA VIIIA 1A 8A 1 2 13 14 15 16 17 2 1 H IIA IIIA IVA VA VIAVIIA He 1.008 2A 3A 4A 5A 6A 7A 4.003 3 4 5 6 7 8 9 10 2 Li Be B C N O F Ne 6.941 9.012 10.81 12.01 14.01 16.00 19.00 20.18 11 12 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 3 Na Mg IIIB IVB VB VIB VIIB ------- VIII IB IIB Al Si P S Cl Ar 22.99 24.31 3B 4B 5B 6B 7B ------- 1B 2B 26.98 28.09 30.97 32.07 35.45 39.95 ------- 8 ------- 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 4 K Ca Sc Ti V Cr Mn Fe Co Ni Cu Zn Ga Ge As Se Br Kr 39.10 40.08 44.96 47.88 50.94 52.00 54.94 55.85 58.47 58.69 63.55 65.39 69.72 72.59 74.92 78.96 79.90 83.80 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 5 Rb Sr Y Zr NbMo Tc Ru Rh PdAgCd In Sn Sb Te I Xe 85.47 87.62 88.91 91.22 92.91 95.94 (98) 101.1 102.9 106.4 107.9 112.4 114.8 118.7 121.8 127.6 126.9 131.3 55 56 57 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 6 Cs Ba La* Hf Ta W Re Os Ir Pt AuHg Tl Pb Bi Po At Rn 132.9 137.3 138.9 178.5 180.9 183.9 186.2 190.2 190.2 195.1 197.0 200.5 204.4 207.2 209.0 (210) (210) (222) 87 88 89 104 105 106 107 108 109 110 111 112 114 116 118 7 Fr Ra Ac~RfDb Sg Bh Hs Mt --- --- --- --- --- --- (223) (226) (227) (257) (260) (263) (262) (265) (266) () () () () () () http://pearl1.lanl.gov/periodic/ (1 of 3) [5/17/2001 4:06:20 PM] A Periodic Table of the Elements at Los Alamos National Laboratory 58 59 60 61 62 63 64 65 66 67 68 69 70 71 Lanthanide Series* Ce Pr NdPmSm Eu Gd TbDyHo Er TmYbLu 140.1 140.9 144.2 (147) 150.4 152.0 157.3 158.9 162.5 164.9 167.3 168.9 173.0 175.0 90 91 92 93 94 95 96 97 98 99 100 101 102 103 Actinide Series~ Th Pa U Np Pu AmCmBk Cf Es FmMdNo Lr 232.0 (231) (238) (237) (242) (243) (247) (247) (249) (254) (253) (256) (254) (257) ** Groups are noted by 3 notation conventions.
    [Show full text]
  • Poisoning of SCR Catalysts by Alkali and Alkaline Earth Metals
    catalysts Review Poisoning of SCR Catalysts by Alkali and Alkaline Earth Metals Luciana Lisi * and Stefano Cimino * Istituto di Scienze e Tecnologie per l’Energia e la Mobilità Sostenibili (STEMS), Consiglio Nazionale delle Ricerche (CNR), Via Guglielmo Marconi 4/10, 80125 Napoli, Italy * Correspondence: [email protected] (L.L.); [email protected] (S.C.) Received: 19 November 2020; Accepted: 10 December 2020; Published: 16 December 2020 Abstract: SCR still represents the most widely applied technique to remove nitrogen oxides from flue gas from both stationary and mobile sources. The catalyst lifetime is greatly affected by the presence of poisoning compounds in the exhaust gas that deactivate the catalysts over time on stream. The progressive and widespread transition towards bio-derived fuels is pushing research efforts to deeply understand and contrast the deactivating effects of some specific poisons among those commonly found in the emissions from combustion processes. In particular, exhaust gases from the combustion of bio-fuels, as well as from municipal waste incineration plants and marine engines, contain large amounts of alkali and alkaline earth metals that can severely affect the acid, redox, and physical properties of the SCR catalysts. This review analyzes recent studies on the effects of alkali and alkaline earth metals on different types of SCR catalysts divided into three main categories (conventional V2O5-WO3/TiO2, supported non-vanadium catalysts and zeolite-based catalysts) specifically focusing on the impact of poisons on the reaction mechanism while highlighting the different type of deactivation affecting each group of catalysts. An overview of the different regeneration techniques aimed at recovering as much as possible the original performance of the catalysts, highlighting the pros and cons, is given.
    [Show full text]
  • V for Vanadium
    in your element V for vanadium Andrea Taroni shares his experience with vanadium — a colourful element with a rich chemistry (and physics!) that is emblematic of all transition metals. uite why I chose to study chemistry changing the colour of the complex. The at university is a mystery, even to me. rest of my undergraduate practical required QI mostly got the general principles, but me to determine the oxidation states of it was as if its details — oxidation, reduction; vanadium upon reducing my solution cis, trans; R, S — or rather which way around with various agents. I vividly recall the those details went, had been designed to sudden changes in colour that came with consistently make me feel like I couldn’t tell each oxidation state switch, and I like to my right hand from my left. It is fair to say I think this gave me a greater appreciation wasn’t a natural at the subject. for the inspired decision to name the One of the first elements I remember element after Vanadis, the Norse goddess encountering in the lab — by attempting more commonly known as Freyja, whose to work with it, as opposed to simply attributes include beauty. PHOTOGRAPHY/ ANDREW LAMBERT LIBRARY PHOTO SCIENCE acknowledging its existence — is vanadium. In fact, many transition metal My inorganic chemistry lab practical compounds have spectacular colours (earning Albert Fert and Peter Grünberg involved the synthesis and analysis of the (pictured), making them ideal for pigments. the 2007 Nobel Prize in Physics in the five-coordinate complex VO(acac)2 (where Their rich redox chemistry is also key to process).
    [Show full text]
  • Toxicological Profile for Vanadium
    TOXICOLOGICAL PROFILE FOR VANADIUM U.S. DEPARTMENT OF HEALTH AND HUMAN SERVICES Public Health Service Agency for Toxic Substances and Disease Registry September 2012 VANADIUM ii DISCLAIMER Use of trade names is for identification only and does not imply endorsement by the Agency for Toxic Substances and Disease Registry, the Public Health Service, or the U.S. Department of Health and Human Services. VANADIUM iii UPDATE STATEMENT A Toxicological Profile for Vanadium, Draft for Public Comment was released in September 2009. This edition supersedes any previously released draft or final profile. Toxicological profiles are revised and republished as necessary. For information regarding the update status of previously released profiles, contact ATSDR at: Agency for Toxic Substances and Disease Registry Division of Toxicology and Human Health Sciences (proposed) Environmental Toxicology Branch (proposed) 1600 Clifton Road NE Mailstop F-62 Atlanta, Georgia 30333 VANADIUM iv This page is intentionally blank. VANADIUM v FOREWORD This toxicological profile is prepared in accordance with guidelines* developed by the Agency for Toxic Substances and Disease Registry (ATSDR) and the Environmental Protection Agency (EPA). The original guidelines were published in the Federal Register on April 17, 1987. Each profile will be revised and republished as necessary. The ATSDR toxicological profile succinctly characterizes the toxicologic and adverse health effects information for the toxic substances each profile describes. Each peer-reviewed profile identifies and reviews the key literature that describes a substance's toxicologic properties. Other pertinent literature is also presented but is described in less detail than the key studies. The profile is not intended to be an exhaustive document; however, more comprehensive sources of specialty information are referenced.
    [Show full text]
  • 14 CAS No.: 7440-62-2(Vanadium) Substance: Vanadium and Its Compounds Chemical Substances Control Law Reference No.: PRTR Law Ca
    14 CAS No.: 7440-62-2(Vanadium) Substance: Vanadium and its compounds Chemical Substances Control Law Reference No.: PRTR Law Cabinet Order No.: 1-321 (Vanadium compounds) Element Symbol: V Atomic Weight: 50.94 1. General information Vanadium, vanadium (IV) oxide, and vanadium (III) oxide are insoluble in water. The aqueous solubilities of vanadium (V) pentoxide, ammonium metavanadate (V), and sodium metavanadate (V) are 700 mg/1,000 g (25°C), 4.8×104 mg/1,000 g (20°C), and 2.1×105 mg/1,000 g (25°C), respectively. Sodium metavanadate (V) and vanadium oxysulfate (IV) are soluble in water. Vanadium oxytrichloride (V) is thought to hydrolyze in the presence of moisture to form vanadium oxide and hydrochloric acid. Potassium vanadate (V) is almost insoluble in cold water. At temperatures lower than 63°C, vanadium (IV) tetrachloride is thought to gradually break down into vanadium trichloride and chlorine, and vanadium (IV) oxydichloride is also believed to break down gradually. Vanadium pentoxide is difficult to break down and bioaccumulation is judged to be low. Vanadium compounds are designated as Class 1 Designated Chemical Substances under the Law Concerning Reporting, etc. of Releases to the Environment of Specific Chemical Substances and Promoting Improvements in Their Management (PRTR Law). Uses of metallic vanadium and vanadium alloys include electronic materials, encapsulant materials, heat-resistant materials, superalloys, and aircraft components. Uses of vanadium steel include turbines for nuclear reactors and turbo engines, cutting tools such as drills, pipelines, tanks, and bridges. Vanadium pentoxide is primarily used as a raw material for metallic vanadium, vanadium alloys, and ferrous alloys such as vanadium steel.
    [Show full text]
  • Wear and Corrosion Resistance of Chromium–Vanadium Carbide Coatings Produced Via Thermo-Reactive Deposition
    coatings Article Wear and Corrosion Resistance of Chromium–Vanadium Carbide Coatings Produced via Thermo-Reactive Deposition Fabio Castillejo 1, Jhon Jairo Olaya 2,* and Jose Edgar Alfonso 3 1 Grupo de Ciencia e Ingeniería de Materiales, Universidad Santo Tomás, Carrera 9 No 51-11, Bogotá 110911, Colombia; [email protected] 2 Departamento de Ingeniería Mecánica y Mecatrónica, Universidad Nacional de Colombia, Carrera 45 No 26-85, Bogotá 110911, Colombia 3 Departamento de Física, Universidad Nacional de Colombia, Carrera 45 No 26-85, Bogotá 110911, Colombia; [email protected] * Correspondence: [email protected] Received: 15 February 2019; Accepted: 20 March 2019; Published: 27 March 2019 Abstract: Chromium carbide, vanadium carbide, and chromium–vanadium mixture coatings were deposited on AISI D2 steel via the thermo-reactive deposition/diffusion (TRD) technique. The carbides were obtained from a salt bath composed of molten borax, ferro-chrome, ferro-vanadium, and aluminum at 1020 ◦C for 4 h. Analysis of the morphology and microstructure of the coatings was done via scanning electron microscopy (SEM) and X-ray diffraction (XRD), respectively. The hardness of the coatings was evaluated using nano-indentation, and the friction coefficient was determined via pin-on-disk (POD) testing. The electrochemical behavior was studied through potentiodynamic polarization tests and electrochemical impedance spectroscopy (EIS). The XRD results show evidence of the presence of V8C7 in the vanadium carbide coating and Cr23C6 and Cr7C3 in the chromium carbide coating. The hardness value for the vanadium–chromium carbide coating was 23 GPa, which was higher than the 6.70 ± 0.28 GPa for the uncoated steel.
    [Show full text]