DOCSLIB.ORG

Aluminium and Aluminium Compounds.Book

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Aluminium and Aluminium Compounds.Book Aluminium and aluminium compounds Health-based recommended occupational exposure limit Gezondheidsraad Health Council of the Netherlands Aan de minister van Sociale Zaken en Werkgelegenheid Onderwerp : Aanbieding advies Aluminium and aluminium compounds Uw kenmerk : DGV/MBO/U-932342 Ons kenmerk : U 6024/HS/fs/459-J63 Bijlagen : 1 Datum : 15 juli 2010 Geachte minister, Graag bied ik u hierbij het advies aan over de gevolgen van beroepsmatige blootstelling aan aluminium en aluminiumverbindingen. Het maakt deel uit van een uitgebreide reeks, waarin gezondheidskundige advieswaarden worden afgeleid voor concentraties van stoffen op de werkplek. Dit advies over aluminium en aluminiumverbindingen is opgesteld door de Commissie Gezondheid en Beroepsmatige Blootstelling aan Stoffen (GBBS) van de Gezondheidsraad en beoordeeld door de Beraads- groep Gezondheid en Omgeving. Ik onderschrijf de conclusies en aanbevelingen van de commissie. Ik heb dit advies vandaag ter kennisname toegezonden aan de minister van Volksgezond- heid, Welzijn en Sport en aan de minister van Volkshuisvesting, Ruimtelijke Ordening en Milieubeheer. Met vriendelijke groet, prof. dr. ir. D. Kromhout waarnemend voorzitter Bezoekadres Postadres Parnassusplein 5 Postbus 16052 2511 VX Den Haag 2500 BB Den Haag Telefoon (070) 340 70 04 Telefax (070) 340 75 23 E-mail: [email protected] www.gr.nl Aluminium and aluminium compounds Health-based recommended occupational exposure limit Dutch Expert Committee on Occupational Safety a Committee of the Health Council of the Netherlands in cooperation with the Nordic Expert Group for Criteria Documentation of Health Risks from Chemicals to: the Minister of Social Affairs and Employment No. 2010/05OSH, The Hague, July 15, 2010 The Health Council of the Netherlands, established in 1902, is an independent scientific advisory body. Its remit is “to advise the government and Parliament on the current level of knowledge with respect to public health issues and health (services) research...” (Section 22, Health Act). The Health Council receives most requests for advice from the Ministers of Health, Welfare & Sport, Housing, Spatial Planning & the Environment, Social Affairs & Employment, Agriculture, Nature & Food Quality, and Education, Culture & Science. The Council can publish advisory reports on its own initia- tive. It usually does this in order to ask attention for developments or trends that are thought to be relevant to government policy. Most Health Council reports are prepared by multidisciplinary committees of Dutch or, sometimes, foreign experts, appointed in a personal capacity. The reports are available to the public. The Health Council of the Netherlands is a member of the European Science Advisory Network for Health (EuSANH), a network of science advisory bodies in Europe. The Health Council of the Netherlands is a member of the International Network of Agencies for Health Technology Assessment (INAHTA), an international collaboration of organisations engaged with health technology assessment. INAHTA This report can be downloaded from www.healthcouncil.nl. Preferred citation: Health Council of the Netherlands. Aluminium and aluminium compounds. Health-based recommended occupational exposure limit. The Hague: Health Council of the Netherlands, 2010; publication no. 2010/05OSH. all rights reserved ISBN: 978-90-5549-806-2 Contents Samenvatting en advieswaarden 11 Executive summary 19 1 Scope 27 1.1 Background 27 1.2 Committee and procedure 27 1.3 Data 28 2 Identity, properties and monitoring 31 2.1 Chemical identity 31 2.2 Physical and chemical properties 35 2.3 EU classification and labelling 38 2.4 Analytical methods 38 3 Sources 43 3.1 Natural occurrence 43 3.2 Man-made sources 44 4 Exposure 49 4.1 General population 49 4.2 Working population 51 Contents 7 5 Kinetics 57 5.1 Absorption 57 5.2 Distribution 59 5.3 Metabolism 62 5.4 Excretion 63 5.5 Possibilities for biological monitoring of exposure 66 5.6 Possibilities for biological effect monitoring 70 5.7 Summary 70 6 Mechanisms of action 73 6.1 Lung toxicity 73 6.2 Neurotoxicity 74 6.3 Bone toxicity 77 6.4 Pro-oxidant activity 77 6.5 Summary of the mechanism of action of aluminium 79 7 Effects in humans 81 7.1 Irritation and sensitisation 81 7.2 General systemic toxicity 83 7.3 Respiratory tract toxicity 85 7.4 Neurotoxicity 90 7.5 Carcinogenicity 100 7.6 Reproduction toxicity 101 7.7 Immunotoxicity 103 7.8 Summary and evaluation 103 8 Animal and in vitro experiments 107 8.1 Irritation and sensitisation 107 8.2 Toxicity due to single exposure 108 8.3 Toxicity due to repeated exposure 109 8.4 Genotoxicity 117 8.5 Reproduction toxicity 121 8.6 Summary and evaluation 123 9 Existing guidelines, standards and evaluations 127 9.1 General population 127 9.2 Working population 127 9.3 Evaluations 129 8 Aluminium and aluminium compounds 10 Hazard assessment 135 10.1 Assessment of the health risk 135 10.2 Recommendation of the health-based occupational exposure limit 140 10.3 Groups at extra risk 141 10.4 Health-based recommended occupational exposure limit 141 10.5 Additional considerations 141 11 Recommendation for research 143 References 145 Annexes 159 A Request for advice 161 B The Committees 163 C Comments on the public draft 167 D ATSDR references 169 E Human data 181 F In vitro data 205 G Animal data 207 Contents 9 10 Aluminium and aluminium compounds Samenvatting en advieswaarden Vraagstelling Op verzoek van de minister van Sociale Zaken en Werkgelegenheid leidt de Gezondheidsraadcommissie Gezondheid en Beroepsmatige Blootstelling aan Stoffen (GBBS, voorheen WGD) gezondheidskundige advieswaarden af voor stoffen in lucht waaraan mensen beroepsmatig blootgesteld kunnen worden. In het voorliggende rapport bespreekt de commissie de gevolgen van blootstelling aan aluminium en een aantal aluminiumverbindingen. Het advies is opgesteld in samenwerking met de Nordic Expert Group for Criteria Documentation of Health Risks from Chemicals (NEG), een adviescom- missie van de Noord-Europese regeringen. De conclusies in het advies zijn gebaseerd op wetenschappelijke publicaties die vóór april 2009 zijn verschenen. Fysische en chemische eigenschappen Op zuurstof en silicium na is aluminium (Al; CAS nummer: 7429-90-5) het meest voorkomende element in de aardkorst. Het gaat daarbij overigens om alu- minium dat is gebonden als oxide, silicaat of fluoride in aarde, (klei-)mineralen en stollingsgesteente en niet om aluminium in zijn metallische elementaire vorm. Elementair aluminium wordt gewonnen uit bauxiet, dat voor 40-60% uit alumi- niumoxide bestaat. Het is een zilverwit, licht, relatief zacht en buigzaam metaal. Samenvatting en advieswaarden 11 In contact met lucht en water (vocht) vormt zich een laagje van aluminiumoxide dat beschermend werkt. Metallisch aluminium lost niet op in water. Aluminium en aluminiumlegeringen worden gebruikt in de metaalverwer- kende industrie, en dan met name voor het vervaardigen van gegoten en gesmede producten. Aluminiumlegeringen worden gebruikt: voor verpakkingen; voor bouw- en constructiedoeleinden; in de transportsector; voor elektrische toepas- singen. Aluminiumverbindingen vinden toepassing in consumentenproducten (bijvoorbeeld maagzuurneutraliserende tabletten, bloedstelpende middelen, gebufferde aspirine, transpiratiewerende preparaten en als voedseladditieven). Aluminiumpoeder tenslotte wordt gebruikt in springstoffen en vuurwerk. Monitoring Omdat aluminium in het milieu alom aanwezig is, moeten er stringente voor- zorgsmaatregelen genomen worden om contaminatie en als gevolg daarvan onjuiste meetresultaten te voorkomen. Omdat aluminium meestal voorkomt als stof(deeltjes), wordt voor monster- neming en -opwerking gebruik gemaakt van de methoden voor bepaling van stof. De lucht wordt dan aangezogen via filters, waarna de filters worden behandeld met een zure oplossing. Met behulp van speciale spectrometrische technieken, zoals bij voorbeeld recentelijk beschreven door het Nederlands-Normalisatie Instituut, wordt vervolgens de hoeveelheid aluminium bepaald, zonder overigens onderscheid te kunnen maken tussen metallisch aluminium en aluminiumverbin- dingen. Ook zijn er methoden voorhanden om aluminium te bepalen in biologische monsters (bloed – plasma, serum, volbloed – en urine). Huidige grenswaarden Nederland kent geen wettelijke grenswaarde voor aluminium of aluminiumver- bindingen. Ook in Europese richtlijnen zijn geen indicatieve grenswaarden vast- gesteld. In Duitsland worden voor stof dat aluminium, aluminiumoxide of alumi- niumhydroxide bevat grenswaarden aanbevolen van 4 (inhaleerbare fractie) en 1,5 mg/m3 (respirabele fractie); voor aluminiumoxidevezels en -rook zijn geen waarden vastgesteld. Het Verenigd Koninkrijk hanteert grenswaarden voor metallisch aluminium en aluminium oxide van 10 en 4 mg/m3 (respectievelijk de inhaleerbare en respi- rabele fractie) en voor oplosbare aluminiumzouten van 2 mg/m3. 12 Aluminium and aluminium compounds Zweden heeft grenswaarden vastgesteld voor oplosbare aluminiumverbindin- gen van 1 mg/m3 en voor zowel metallisch aluminium en aluminiumoxide van 5 en 2 mg/m3 (voor respectievelijk de totale en respirabele fractie). In Denemarken zijn er waarden voor aluminiumpoeder en -stof (5 en 2 mg/m3, voor respectieve- lijk de totale en respirabele fractie), oplosbare aluminiumzouten (1 mg/m3), alu- miniumoxide (5 en 2 mg/m3) en aluminiumrook (5 mg/m3). In de Verenigde Staten heeft de ACGIH (een organisatie van arbeidshygiënis- ten) de verschillende grenswaarden voor de verschillende vormen van onoplos- baar
Load more

Recommended publications
  • 1201: Introduction to Aluminium As an Engineering Material
    TALAT Lecture 1201 Introduction to Aluminium as an Engineering Material 23 pages, 26 figures (also available as overheads) Basic Level prepared by M H Jacobs * Interdisciplinary Research Centre in Materials The University of Birmingham, UK Objectives To provide an introduction to metallurgical concepts necessary to understand how structural features of aluminium alloys are influenced by alloy composition, processing and heat treatment, and the basic affects of these parameters on the mechanical properties, and hence engineering applications, of the alloys. It is assumed that the reader has some elementary knowledge of physics, chemistry and mathematics. Date of Issue: 1999 EAA - European Aluminium Association 1201 Introduction to Aluminium as an Engineering Material Contents (26 figures) 1201 Introduction to Aluminium as an Engineering Material _____________________ 2 1201.01. Basic mechanical and physical properties__________________________________ 3 1201.01.01 Background _______________________________________________________________ 3 1201.01.02 Commercially pure aluminium ______________________________________________ 4 1201.02 Crystal structure and defects _____________________________________________ 6 1201.02.01 Crystals and atomic bonding __________________________________________________ 6 1201.02.02 Atomic structure of aluminium ______________________________________________ 8 1201.02.03 Crystal structures _________________________________________________________ 8 1201.02.04 Some comments on crystal structures of materials
    [Show full text]
  • The Development of the Periodic Table and Its Consequences Citation: J
    Firenze University Press www.fupress.com/substantia The Development of the Periodic Table and its Consequences Citation: J. Emsley (2019) The Devel- opment of the Periodic Table and its Consequences. Substantia 3(2) Suppl. 5: 15-27. doi: 10.13128/Substantia-297 John Emsley Copyright: © 2019 J. Emsley. This is Alameda Lodge, 23a Alameda Road, Ampthill, MK45 2LA, UK an open access, peer-reviewed article E-mail: [email protected] published by Firenze University Press (http://www.fupress.com/substantia) and distributed under the terms of the Abstract. Chemistry is fortunate among the sciences in having an icon that is instant- Creative Commons Attribution License, ly recognisable around the world: the periodic table. The United Nations has deemed which permits unrestricted use, distri- 2019 to be the International Year of the Periodic Table, in commemoration of the 150th bution, and reproduction in any medi- anniversary of the first paper in which it appeared. That had been written by a Russian um, provided the original author and chemist, Dmitri Mendeleev, and was published in May 1869. Since then, there have source are credited. been many versions of the table, but one format has come to be the most widely used Data Availability Statement: All rel- and is to be seen everywhere. The route to this preferred form of the table makes an evant data are within the paper and its interesting story. Supporting Information files. Keywords. Periodic table, Mendeleev, Newlands, Deming, Seaborg. Competing Interests: The Author(s) declare(s) no conflict of interest. INTRODUCTION There are hundreds of periodic tables but the one that is widely repro- duced has the approval of the International Union of Pure and Applied Chemistry (IUPAC) and is shown in Fig.1.
    [Show full text]
  • Sodium Aluminium Silicate (Tentative)
    SODIUM ALUMINIUM SILICATE (TENTATIVE) th Prepared at the 80 JECFA and published in FAO JECFA Monographs 17 (2015), superseding tentative specifications prepared at the 77th JECFA (2013) and published in FAO JECFA Monographs 14 (2013). An ADI 'not specified' for silicon dioxide and certain silicates was established at the 29th JECFA (1985). A PTWI of 2 mg/kg bw for total aluminium was established at the 74th JECFA (2011). The PTWI applies to all aluminium compounds in food, including food additives. Information required: Functional uses other than anticaking agent, if any, and information on the types of products in which it is used and the use levels in these products Data on solubility using the procedure documented in the “Compendium of Food Additives Specifications, Vol. 4, Analytical methods” Data on the impurities soluble in 0.5 M hydrochloric acid, from a minimum of five batches. If a different extraction and determination method is used, provide data along with details of method and QC data. Suitability of the analytical method for the determination of aluminium, silicon and sodium using the proposed “Method of assay” along with data, from a minimum of five batches, using the proposed method. If a different method is used, provide data along with details of the method and QC data. SYNONYMS Sodium silicoaluminate; sodium aluminosilicate; aluminium sodium silicate; silicic acid, aluminium sodium salt; INS No. 554 DEFINITION Sodium aluminium silicate is a series of amorphous hydrated sodium aluminium silicates with varying proportions of Na2O, Al2O3 and SiO2. It is manufactured by, precipitation process, reacting aluminium sulphate and sodium silicate.
    [Show full text]
  • Determination of Aluminium As Oxide
    DETERMINATION OF ALUMINIUM AS OXIDE By William Blum CONTENTS Page I. Introduction 515 II. General principles 516 III. Historical 516 IV. Precipitation of aluminium hydroxide. 518 1. Hydrogen electrode studies 518 (a) The method 518 (b) Apparatus and solutions employed 518 (c) Results of hydrogen electrode experiments 519 (d) Conclusions from hydrogen electrode experiments 520 2. Selection of an indicator for denning the conditions of precipita- '. tion . 522 3. Factors affecting the form of the precipitate 524 4. Precipitation in the presence of iron 525 V. Washing the precipitate . 525 VI. Separation from other elements 526 VII. Ignition and weighing of the precipitate 528 1. Hygroscopicity of aluminium oxide 529 2. Temperature and time of ignition 529 3. Effect of ammonium chloride upon the ignition 531 VIII. Procedure recommended 532 IX. Confirmatory experiments 532 X. Conclusions '534 I. INTRODUCTION Although a considerable number of precipitants have been pro- posed for the determination of aluminium, direct precipitation of aluminium hydroxide by means of ammonium hydroxide, fol- lowed by ignition to oxide, is most commonly used, especially if no separation from iron is desired, in which latter case special methods must be employed. While the general principles involved in this determination are extremely simple, it has long been recog- nized that certain precautions in the precipitation, washing, and ignition are necessary if accurate results are to be obtained. While, however, most of these details have been studied and dis- cussed by numerous authors, it is noteworthy that few publica- tions or textbooks have taken account of all the factors. In the 515 ; 516 Bulletin of the Bureau of Standards [Voi.i3 present paper it seems desirable, therefore, to assemble the various recommendations and to consider their basis and their accuracy.
    [Show full text]
  • Safety Data Sheet
    SAFETY DATA SHEET FennoFloc A 19 Ref. /US/EN Revision Date: 02/09/2017 Previous date: 02/09/2017 Print Date:04/20/2017 1. IDENTIFICATION OF THE SUBSTANCE/MIXTURE AND OF THE COMPANY/UNDERTAKING Product information Product name FennoFloc A 19 Recommended use of the chemical and restrictions on use Use of the Substance/Mixture Recommended restrictions on use There are no uses advised against. Supplier's details Kemira Chemicals, Inc. 1000 Parkwood Circle, Suite 500 30339 Atlanta USA Telephone+17704361542, Telefax. +17704363432 HEAD OFFICE Kemira Oyj P.O. Box 330 00101 HELSINKI FINLAND Telephone +358108611 Telefax +358108621124 Emergency telephone number CHEMTREC: 1-800-424-9300 CANUTEC: 1-613-996-6666 2. HAZARDS IDENTIFICATION Classification of the substance or mixture Corrosive to metals; Category 1; May be corrosive to metals.; Serious eye damage; Category 1; Causes serious eye damage.; GHS-Labelling 1/14 SAFETY DATA SHEET FennoFloc A 19 Ref. /US/EN Revision Date: 02/09/2017 Previous date: 02/09/2017 Print Date:04/20/2017 Hazard pictograms : Signal word : Danger Hazard statements : Hazard statements: H290 May be corrosive to metals. H318 Causes serious eye damage. Precautionary statements : Prevention: P234 Keep only in original container. P264 Wash face, hands and any exposed skin thoroughly after handling. P280 Wear protective gloves/ eye protection/ face protection. Response: P390 Absorb spillage to prevent material damage. P305 + P351 + P338 IF IN EYES: Rinse cautiously with water for several minutes. Remove contact lenses, if present and easy to do. Continue rinsing. P310 Immediately call a POISON CENTER or doctor/ physician. Storage: P406 Store in corrosive resistant container with a resistant inner liner.
    [Show full text]
  • WO 2009/112156 Al
    (12) INTERNATIONALAPPLICATION PUBLISHED UNDER THE PATENT COOPERATION TREATY (PCT) (19) World Intellectual Property Organization International Bureau (10) International Publication Number (43) International Publication Date 17 September 2009 (17.09.2009) WO 2009/112156 Al (51) International Patent Classification: AO, AT, AU, AZ, BA, BB, BG, BH, BR, BW, BY, BZ, A61K 45/06 (2006.01) A61P 1/04 (2006.01) CA, CH, CN, CO, CR, CU, CZ, DE, DK, DM, DO, DZ, A61K 9/20 (2006.01) EC, EE, EG, ES, FI, GB, GD, GE, GH, GM, GT, HN, HR, HU, ID, IL, IN, IS, JP, KE, KG, KM, KN, KP, KR, (21) International Application Number: KZ, LA, LC, LK, LR, LS, LT, LU, LY, MA, MD, ME, PCT/EP2009/001353 MG, MK, MN, MW, MX, MY, MZ, NA, NG, NI, NO, (22) International Filing Date: NZ, OM, PG, PH, PL, PT, RO, RS, RU, SC, SD, SE, SG, 26 February 2009 (26.02.2009) SK, SL, SM, ST, SV, SY, TJ, TM, TN, TR, TT, TZ, UA, UG, US, UZ, VC, VN, ZA, ZM, ZW. (25) Filing Language: English (84) Designated States (unless otherwise indicated, for every (26) Publication Language: English kind of regional protection available): ARIPO (BW, GH, (30) Priority Data: GM, KE, LS, MW, MZ, NA, SD, SL, SZ, TZ, UG, ZM, 08290223.0 10 March 2008 (10.03.2008) EP ZW), Eurasian (AM, AZ, BY, KG, KZ, MD, RU, TJ, TM), European (AT, BE, BG, CH, CY, CZ, DE, DK, EE, (71) Applicant (for all designated States except US): BAYER ES, FI, FR, GB, GR, HR, HU, IE, IS, IT, LT, LU, LV, CONSUMER CARE AG [CWCH]; Peter-Merian-Str.
    [Show full text]
  • A Critical Appraisal and Review of Aluminium Chloride Electrolysis for the Production of Aluminium
    Bulletin of Eledrochemistry 1 (5) Sep.-Od. 1985, pp. 483488 A CRITICAL APPRAISAL AND REVIEW OF ALUMINIUM CHLORIDE ELECTROLYSIS FOR THE PRODUCTION OF ALUMINIUM C N KANNAN and PS DESIKAN Central Electrochemical Research Institute, Karaikudi - 623 006, ABSTRACT This paper is an attempt to examine the current state of art of aluminium chloride electrolysis through a review of all the available published literature and patents so that this could help the formulation of the plans of work for any serious R&D effort to develop the chloride te&nolcgy in this country. Even though the development of technology for aluminium chloride electrolysis is being carried out in a big way by ALCOA and a few other multinational companies for the past several years, many of the data and information are lacking in published literature and the answers to various critical questions have to be found only through inferences from the meagre information available in patents. It was therefore thought fit to undertake a thorough review of all the basic applied and R&Dwork that are reported in this field and critically assess the various problems to be tackled to evolve a viable technology. This review confines itself to the electrolytic aspect and those relating to the material preparation will be taken up separately later. Key words : Production of aluminium. Molten salt electrolysis, chlorination of alumina INTRODUCTION The most obvious advantages of the aluminium chloride smelting are 131 : he need to develop a new technology for aluminium metal production 1. Substantially lower working temperature (700°C) compared to Hall- T has been felt very much in the major aluminium producing countries Heroult cell (980°C).
    [Show full text]
  • Aluminum Chloride 7446-70-0 >95
    SAFETY DATA SHEET Creation Date 10-Sep-2010 Revision Date 27-May-2019 Revision Number 6 1. Identification Product Name Aluminium chloride Cat No. : AC217460000; AC217460025; AC217460050; AC217461000; AC217465000 CAS-No 7446-70-0 Synonyms Aluminium trichloride Recommended Use Laboratory chemicals. Uses advised against Food, drug, pesticide or biocidal product use. Details of the supplier of the safety data sheet Company Fisher Scientific Acros Organics One Reagent Lane One Reagent Lane Fair Lawn, NJ 07410 Fair Lawn, NJ 07410 Tel: (201) 796-7100 Emergency Telephone Number For information US call: 001-800-ACROS-01 / Europe call: +32 14 57 52 11 Emergency Number US:001-201-796-7100 / Europe: +32 14 57 52 99 CHEMTREC Tel. No.US:001-800-424-9300 / Europe:001-703-527-3887 2. Hazard(s) identification Classification This chemical is considered hazardous by the 2012 OSHA Hazard Communication Standard (29 CFR 1910.1200) Skin Corrosion/Irritation Category 1 B Serious Eye Damage/Eye Irritation Category 1 Specific target organ toxicity (single exposure) Category 3 Target Organs - Respiratory system. Label Elements Signal Word Danger Hazard Statements Causes severe skin burns and eye damage May cause respiratory irritation ______________________________________________________________________________________________ Page 1 / 7 Aluminium chloride Revision Date 27-May-2019 ______________________________________________________________________________________________ Precautionary Statements Prevention Do not breathe dust/fume/gas/mist/vapors/spray Wash face, hands and any exposed skin thoroughly after handling Wear protective gloves/protective clothing/eye protection/face protection Use only outdoors or in a well-ventilated area Response Immediately call a POISON CENTER or doctor/physician Inhalation IF INHALED: Remove victim to fresh air and keep at rest in a position comfortable for breathing Skin IF ON SKIN (or hair): Take off immediately all contaminated clothing.
    [Show full text]
  • United States Patent Office
    Patented Feb. 18, 193E _ UNITED STATES PATENT OFFICE PROCESS FOR THE PRODUCTION OF AL ' ' LOYS OF THE ‘EARTH METALS WITH LEAD OR OTHER METALS I ‘Gustaf?ewton Kirsebom, Oslo, Norway, assignor to Calloy limited, London, England, an English . joint-stock company -' . No Drawing. Application December 22, 1932, snug: No. 648,443. \In Great Britain June 11, 9 Claims. (Cl. 75—1) This'invention irelatesto a new or improved pounds of the alkaline earth metals, fox-example method of process for the production of alkaline from the alkaline earth metal silicates. earth metals and alloys thereof with lead or other . In the process as set out above it must be v_ metals such as are hereinafter de?ned. understood that the term.“alkaline earth metals" I ere are certainmetals, especially lead, and includes not only calcium, strontium and barium, ' cadmium which do not readily alloy with alu but also magnesium and beryllium. minium when both are in a molten condition and Where cadmium is employed in place of lead v in the presence of each other, e. g., when molten the procedure is similar and when‘ the alloy of lead is added to a bath of molten aluminium (or cadmium with the alkaline earth metal has been .10 whenlead and aluminium are melted together) formed-on completion of the process-the cad 10 . these two metals will not form an alloy but will mium can be distilled off so that the process af form separate layers which are not substantially fords a ready means of preparing the alkaline ' soluble in each other; and this I utilize in the earth metals in substantially pure condition.
    [Show full text]
  • Alcl3(G)=3Alcl(G) Reaction in the Subhalide Process of Aluminium (Study of Extractive Metallurgy of Aluminium (1))
    Equilibrium of the 2Al(l)+AlCl3(g)=3AlCl(g) Reaction in the Subhalide Process of Aluminium (Study of Extractive Metallurgy of Aluminium (1)) By Takeaki Kikuchi*, Toshio Kurosawa* and Testuo Yagihashi* Equilibriumconstants of a fundamental reaction of the aluminium subhalide process, 2Al(l)+AlCl3(g)= 3AlCl(g), were determined by the flow method using argon carrier between 1000℃ and 1250℃. As a result of this experiment, equilibrium constants and standard free energy were obtained by the following equation: The heat of formation and entropy of AlCl(g) obtained from the experimental data and other thermodynamic values were -22,250cal/mot and 48.7cal/mol respectively. By the use of the equilibrium constants, the reaction ratio of aluminium trichloride was calculated at a reduced pressure and in argon carrier, respectively. (Receivedmarch 10, 1964) I. Introduction trichloride supplied to the reaction zone were applied Aluminium is produced by means of the fused salt previously. In this investigation, the latter method electrolysis using alumina obtained mainly from rela- was selected to obtain the equilibrium constants. tively higher grade bauxite. However, another 1. Experimental apparatus extraction method called the Gross or subhalide process has recently been investigated, and some technological The apparatus used in this experiment is shown by or industrialization reports have already been the schematic diagram in Fig. 1. The apparatus con- sists of an argon purifier, aluminium trichloride evapora- published. In this process, crude aluminium alloy is produced tor, reaction tube, and condensing tube of aluminium by reduction of alumina bearing ores with carbonaceous trichloride gas. Argon in a bomb was purified and reducing material such as coke or charcoal in the measured by passing through concentrated sulphuric acid, calcium chloride, soda lime, phosphorus pentoxide first step, and then aluminium trichloride gas is alld magnesium chip hea七ed at 400℃.
    [Show full text]
  • SYNTHESIS of SOME ALUMINIUM SILICATES* by R. M. CARR~ And
    SYNTHESIS OF SOME ALUMINIUM SILICATES* By R. M. CARR~and J. B. DIXON~ Studies in the system A12034Si02 under hydrothermal conditions where three different starting materials (amorphous alumina-quartz, amorphous silica-kaolinite, quartz-kaolinite) were investigated in "pinched-tube" experiments1 were followed by a redetermination in sealed-tube experiments of the synthesis fields obtained from amorphous silica-kaolinite and quartz-kaolinite.2 A synthesis diagram for the starting material amorphous alumina-quartz has now been redetermined in sealed-tube experiments. Experimental The pressure equipment used is similar to that already described.2 Modifications to the equipment, in the form of stellite test-tube bombs each coupled to a Bourdon pressure gauge and controlled with an Ether transitrol temperature regulator, enabled more effective control to be attained in some of the experiments. Errors in temperature control were within &l% at all temperatures. Quartz and amorphous (chromatographic) alumina were mixed in the molecular proportions A1203,4SiOz and Aln03,6SiOz. Samples together with water were placed in silver capsules and sealed. Runs commenced with rapid heating periods (e.g. from room temperature to 400' in 20 min) and were terminated with air quenching. Products were examined with a Philips X-ray diffractometer using filtered Cu radiation. Results A comparison of synthesis field boundary temperatures for pinched-tube and sealed-tube experiments with the starting material amorphous alumina-quartz is given in Table 1. Minor amounts of boehmite were present in many low-temperature runs, indicating sluggish reaction between this phase and quartz. Two decomposition experiments provided confirmation of the synthesis boundaries. Synthetic corundum heated at 490' under a hydrostatic pressure of 30000 lb/inZ was partly altered to pyrophyllite, and kaolinite was obtained from synthetic pyrophyllite at 370".
    [Show full text]
  • Periodic Table 1 Periodic Table
    Periodic table 1 Periodic table This article is about the table used in chemistry. For other uses, see Periodic table (disambiguation). The periodic table is a tabular arrangement of the chemical elements, organized on the basis of their atomic numbers (numbers of protons in the nucleus), electron configurations , and recurring chemical properties. Elements are presented in order of increasing atomic number, which is typically listed with the chemical symbol in each box. The standard form of the table consists of a grid of elements laid out in 18 columns and 7 Standard 18-column form of the periodic table. For the color legend, see section Layout, rows, with a double row of elements under the larger table. below that. The table can also be deconstructed into four rectangular blocks: the s-block to the left, the p-block to the right, the d-block in the middle, and the f-block below that. The rows of the table are called periods; the columns are called groups, with some of these having names such as halogens or noble gases. Since, by definition, a periodic table incorporates recurring trends, any such table can be used to derive relationships between the properties of the elements and predict the properties of new, yet to be discovered or synthesized, elements. As a result, a periodic table—whether in the standard form or some other variant—provides a useful framework for analyzing chemical behavior, and such tables are widely used in chemistry and other sciences. Although precursors exist, Dmitri Mendeleev is generally credited with the publication, in 1869, of the first widely recognized periodic table.
    [Show full text]