Aluminium ... Third edition, revised and enlarged, etc

Front matter

ALUMINIUM i ALUMINIUM: ITS HISTORY, OCCURRENCE, PROPERTIES METALLURGY AND APPLICATIONS, INCLUDING ITS ALLOYS. BY JOSEPH W. RICHARDS, A. C, Ph.D., INSTRUCTOR IN METALLURGY AT THE LEHIGH UNIVERSITY. THIRD EDITION, REVISED AND ENLARGED. II.LUSTKATKD hv FORTY FOUR ENGRAVINGS AND TWO DIAGRAMS PHILADELPHIA : HENRY CA R E Y B A I R I) & C 0 . , INDUSTRIAL PUBLISHERS, BOOKSELLERS, AND IMPORTERS, No. 810 Walnut Street. LONDON : SAMPSON LOW, MARSTON & CO., Limited, st. dunstan's house, fetter lane, fleet street. 1896, Copyright by- JOSEPH W. RICHARDS, 1895. Printed by the WICKERSHAM PRINTING CO., 53 and 55 N. Queen Street, Lancaster, Pa.. U. S. A, Dedication. TO THE MEMORY OF tfrebericfc Mbbler OF GOTTINGEN, THE DISCOVERER OF ALUMINIUM, AND OF Ibenrt Sainte=Clatre Seville OF PARIS J FOUNDER OF THE ALUMINIUM INDUSTRY. THE FRUITS OF WHOSE LABORS HAVE ENRICHED SCIENCE AND BENEFITED MANKIND.

Preface

TO THE THIRD EDITION. TEN years ago aluminium was an almost unknown metal ; then it sold for twelve dollars a pound, now it is bought for fifty cents ; then the yearly production was less than is the present daily output ; then only three books had been written about it, since then seven have appeared and two journals have been es tablished to represent it. The lowering of the price, the increased production, the wide circulation of reliable information about aluminium, have brought to pass the dream of Deville, for it has truly become a metal of every-day life. The abundance of aluminium in nature, the purity of its ores, its wonderful lightness and adaptability to numerous purposes, indicate that the goal of the aluminium industry will be reached only when this metal ranks next to iron in its usefulness to man kind.

To assist this consummation by furnishing all the reliable in formation about aluminium, to thus enlighten the general reader, help the workman, instruct the student, assist the experimenter, and in every way to speed the industry on its destined path, is the raison d'etre of this work. The writer thanks the public for its generous appreciation of his past endeavors. The volume has been revised to date, several chapters have been largely re-written, and every effort has been made to make the work worthy of the splendid industry which it represents. Joseph William Richards. The Lehigh University, Bethlehem, Pa., October 23, 1S95,

PREFACE.

TO THE SECOND EDITION. If it was true that no apology was necessary in presenting a work on Aluminium in English, as stated in the preface to the first edition of this book, it is equally true that still less apology is necessary in offering an improvement on that work. The present volume is designed to be an improvement on the former one in the following respects : Mistakes have been corrected wherever detected by the author or pointed out by his friends ; in some instances the order of treatment of different parts has been revised, so as to bring them into strict, logical sequence ; the more strictly historical processes are described in greater detail, in order to preserve a complete record of the rise of the aluminium industry; chapters have been added treating on the properties and the preparation of aluminium compounds, on the theoretical aspect of the reduction of aluminium com pounds, and on the analysis of commercial aluminium and its common alloys ; the original chapters have been in several cases sub-divided, and every part treated more by itself and in greater detail than before ; finally, additions have been made through out recording and describing the progress achieved in the last three years, with a completeness which it is hoped is up to the standard of the rest of the book.

The method of treatment in the present edition will be found to be more critical, for wherever a reasonable doubt might be expressed as to the correctness of certain claims, or a rational explanation advanced for certain phenomena, the author has not

PREFACE.

TO THE SECOND EDITION. X hesitated to put his best thought on the question and to state his conclusions unreservedly. The friendly criticisms of the scientific press and their suggestions have been kept in view in preparing this new edition. The spelling " aluminium " has been retained, because no sufficient reasons have been advanced for changing it to " aluminum;" and even if each way was equally old and as well sanctioned by usage and analogy as the other, the author's choice would be the longer spelling, as being more euphonious and agreeable to the ear. It has been the author's endeavor to make this volume as complete as possible, as accurate as possible, to write it in a manner which will be entertaining to the general reader, and to furnish a treatise which will be of practical value to the practical metallurgist, as well as of scientific merit where it touches on matters of theory. J. W. R. Bethlehem, Pa., March 12, i8go.

PREFACE.

TO THE FIRST EDITION. No apology is necessary in presenting a work on Aluminium in English. In 1858 Tissier Bros. published in France a small book on the subject. H. St. Claire Deville, the originator of the aluminium industry, published a treatise, also in French, in 1859. Deville's book is still the standard on the subject. Until December, 1885, we have an intermission, and then a work by Dr. Mierzinski, forming one of Hartleben's Chemisch-Technische Bibliothek, which is a fair presentation of the industry up to about 1883, this being a German contribution. Probably be cause the English-speaking people have taken comparatively little hand in this subject, we find no systematic treatise on aluminium in our language. The present work aims to present the subject in its entirety to the English reader.

Tissier, Deville, Mierzinski, and the German, French, and English scientific periodicals have been freely consulted and extracted from, full credit being given in each case to the author or journal. As this art has of late advanced so rapidly, it has been a special aim to give everything that has been printed up to the time of publication. The different parts of the work are arranged in what seemed their logical order, corresponding closely to that followed by Deville. The Appendix contains an account of laboratory ex periments, etc., several of which, it is trusted, may be of value. In conclusion, the author wishes to thank the Faculty of his " Alma Mater," Lehigh University, for their permission to use .xi)

PREFACE.

TO THE FIRST EDITION. XII his Thesis on Aluminium as the basis of this treatise ; also, to acknowledge his indebtedness to Dr. Wm. H. Greene, of Phil adelphia, for assistance rendered in the preparation of the work for the press. J. W. R. Philadelphia, November 23, iSSb. ABBREVIATIONS USED IN MAKING REFERENCES. SEPARATE WORKS ON ALUMINIUM {Arranged chronologically. ) Tissier Recherche de l'Aluminiutu. C. & H. Tissier. Paris : J. Hetzel et Cie. 1858. Uhlenhuth Die Darstellung des Aluminiums. Ed. Uhlenhuth. Quedlinburg : G. Basse. 1858. Deville De l'Aluminium. H. St. Claire Deville. Paris : Mallet-Bachelier. 1S59. Mierzinski Die Fabrikation des Aluminiums. Dr. Stanislaus Mierzinski. Vienna : Hartleben's Chemisch-technische Bibliothek. 1885. Richards (ist Ed.) Aluminium. Joseph W. Richards. Philadelphia : Henry Carey Baird & Co. 1887.

Richards (2nd Ed.) Aluminium. Joseph W. Richards. Philadelphia : Henry Carey Baird & Co. 1890. Le Verrier Note sur la Metallurgie de l'Aluminium. U. Le Verrier. Paris: Baudry et Cie. 1891. Minet L'Aluminium. Adolphe Minet. Paris : Bernard Tignol. 1892. Lejeal L'Aluminium. Adolphe Lejeal. Paris: J. B. Bailliere et Fils. 1894. TREATISES IN ENCYCLOPÆDIAS. Fremy Enclyclopedie Chimique. Fremy. Paris : Ch. Dunod. Art: L'Aluminium par Margottet (1S83). Art : L'Aluminium et ses Alliages par Wickersheimer (1890). Kerl and Stohman Enclyclopadisches Handbuch der Technischen Chemie. 4th Ed. Brunswick : Vieweg und Sohn. 1886. Art: Aluminium von R. Biederman. Watts' Dictionarv of Chemistry. Watts ( xiii ) ABBREVIATIONS USED IN MARING REFERENCES. XIV JOURNALS AND PERIODICALS. Ann. de Chim. et de Phys. . .

Annales de Chimie et de Physique. Ann. der Chem. und Pharm. 1 Liebig's Annalen der Chemie und Phar- Liebig's Ann / macie. Liebig's Ann. Bulletin de la Societe Chimique de Paris. The Chemical News. Bull, de la Soc. Chim. Chem. News . . Chem. Zeit. . Compt. Rend. Chemiker Zeitung (Cothen). Comptes Rendus de les Seances de l'Academie. Paris Dingler's Polytechnisches Journal. The Engineering and Mining Journal. Jahresbericht ueber die Fortschritte der Dingl. Jrnl. E. and M. J. Jahresb. der Chem. Chemie. Jrnl. Chem. Soc. . Jml. der Pharm. . Jrnl. fiir pr. Chem. Mon. Scientif. . . Journal of the Chemical Society. Journal der Pharmacie. Erdmann's Journal fiir praktische Chemie. Le Moniteur Scientifique. Dr. Quesnesville. The London and Edinburgh Philosophical Phil. Mag. Magazine. Phil. Trans. Transactions of the Royal Philosophical Societv.

PoggendorfPs Annalen. Polvtechnisches Ceutral-Blatt. Pogg. Ann. Poly. Centr. Blatt. Proc. Ac. Nat. Sci. Proceedings of the Academy of Natural Sciences (Philadelphia). Quarterly Journal Rpt. Brit. A. A. S. Quarterly Journal of the Society of Arts. Report of the British Association for the Advancement of Science. Sci. Am. (Suppl.) Wagner's Jahresb. Scientific American (Supplement). Wagner's Jahresbericht der Chemischen Technologie. Zeit. stir anal. Chem. Zeitschrift fiir Aualytische Chemie. JOURNALS REPRESENTING THE ALUMINIUM INDUSTRY. The Aluminum World .... New York. Published monthly. Established September, 1894. L'Aluminium Paris. Published monthly. Established Januar3', 1895. CONTENTS.

Chapter I

History of Aluminium. page The alumen of Pliny; Alumen Roccæ or rock alum; Alums and vitriols confounded ............ 1 Paracelsus distinguishes alums from vitriols; Views of Ettmiiller, Stahl, Hoffman, Geoffrey, Hellot and Pott, on the nature of the base of alum; Marggraff's dissertations on alum and its earth; Morveau fixes the nomenclature of alumina ........ 2 The search for aluminium; Macquer's supposition; Baron's attempts to reduce alumina; Lavoisier's views on the nature of alumina . . 3 Ruprecht and Tondi's experiments; Criticisms of Savaresi, Klaproth and Karsten; Dr. Hare melts alumina without noticing any reduction; Sir Humphry Davy attacks the earths with his great batter}- . . 4 Davy's experiments on reducing alumina; He reduces it in the electric arc in presence of iron; He suggests a name for the metal ... 5 Prof. Benjamin Silliman's experiment with Dr. Hare's blow-pipe; Oersted's attempt to reduce aluminium chloride; Berzelius' attempt to reduce cryolite ........... 6 Professor Frederick Wohler, of Gottingen, isolates aluminium as a metallic powder, in 1827 7 Wohler obtains the metal in globules, in 1845; Professor Henri Saint- Claire Deville obtains aluminium en masse, in 1854 .... 8 Deville's first attempts; His paper read before the French Academy on February 6, 1854 9 The Academy aids Deville in his further work ; A reclamation by Chenot; Further experiments at the Ecole Normale; Reduction of aluminium chloride by the battery ....... 10 Deville's experiments in manufacturing sodium ; Installation of the sodium process at Rousseau Bros. chemical works at La Glaciere; Deville and Bunsen publish their electrolytic methods; The Emperor Napoleon III. becomes interested and defrays the expense of further experiments . . .......... 11 CONTENTS.

XVI PAGE The Tissier Bros. experiment on producing sodium; Deville's work at Javel; The industry on a firm basis 12 Exhibit of aluminium at the Paris Exposition, 1855; Misunderstanding between Deville and the Tissier Bros 13 Tissier Bros. start an aluminium works near Rouen; History of this enterprise ......-.■-••" Deville and his friends put up a large plant at La Glaciere; Removal to Nanterre; Removal to Pechiney and Co.'s works at Salindres; Tissier Bros. publish their "Recherches sur l'Aluminium " (1858) . . 1-5 Deville publishes his " De l'Aluminium " (1S59); His conclusions as to the usefulness of aluminium ......... 16 Experiments of Dr. Percy and H. Rose on reducing cryolite; Manufacture of aluminium by A. Monnier, of Camden, N. J.; Calculation of cost of the new metal by W. J. Taylor ....... 1" The first aluminium works in England, at Battersea (1S58); Bell Bros. works near Newcastle-on-Tyne; Project to start works at Berlin; Dr. Clemens Winckler's retrospect, 1S79 ....... 18 Condition of the aluminium industry in 1879 ...... 19 The industry from 1S79 to 1882; W. Weldon's views on its prospects in 18S3 20 The search for a substitute for sodium; Webster's improvements in the industry ............. 21 H. Y. Castner's invention for producing sodium; His experiments in New York ............ 22 Castner's demonstration in England; Unites with Webster to form the "Aluminium Company, Limited; " Large works at Oldbury near Birmingham, stop making aluminium in 1891 ...... 23 Revival of electric methods, using dynamos instead of the battery; Gratzel's process ........... 24 Kleiner's process; Hall's process, invented in 1886, essentially different in principle from previous attempts ....... 25 Incorporation of the Pittsburgh Reduction Co. to work Hall's process; Works at Kensington, Pa., and Niagara Falls; Minet's experiments at Creil and works at Saint Michel, Savoy 26 The electric-furnace methods; Siemens furnace; Grabau's experiments; Mierzinski's remarks ........ ,27 Cowles Bros. process, 1885; Plant at Lockport, N. Y., and works in England; The principle of the process ...... 28 Heroult's processes; Principle of his alloy process .... 29 The "Aluminium Industrie Actien Gesellschaft" formed to work Heroult's processes; Dr. Kiliani, manager of their works at the Falls of the Rhine; The Heroult process in France .... 30 Experiments with Heroult's process in the United States; The "Alliance Aluminium Co., of London," formed to work Netto's sodium process. 31 Failure of the Alliance Aluminium Co.; Grabau's improvements in pro- CONTENTS.

XVII PAGE ducing sodium and aluminium fluoride; Colonel Frishmuth's works in Philadelphia 32 Exhibit of aluminium at the Paris Exposition, 1889; Progress of the industry since 1S90 33 The Cowles Electric Smelting Co. sued for infringement of the Hall process; Exhibits of aluminium at the Columbian Exposition in Chicago, 1893; The production of aluminium one of the great achievements of the century .......... 34 Statistics; The decline in the price of aluminium and aluminium bronze. 35 Production of aluminium in France from 1854 to 1892; Production in England; In Switzerland 36 Production of the United States from 1883 to 1894; Total aluminium produced in the world to the end of 1892; World's production in 1893; An estimate of the production in 1894 ....... 37 The probable production in 1S95 38

Chapter II

Occurrence of Aluminium in Nature. Clarke's estimate of the proportion of aluminium iu the earth's crust; Not found metallic; Most frequent combinations in rocks, soils and clays; Occurrence in some plants; Ricciardi's experiments on the assimilation of alumina by plants ....... 39 Composition of the most frequent aluminium minerals; Bauxite the most useful mineral for the aluminium industry . . . . .40 Localities in which bauxite occurs ; Deposits worked in the United States; Value per ton .......... 41 Analyses of foreign bauxites ......... 42 Analyses of American bauxites ........ 43 Laur's generalizations concerning French bauxites . . . .44 Hunt's generalizations on American bauxites; The occurrence of cryolite in Greenland ........... 45 Composition of cryolite; Amount imported into the United States; Description of a small deposit in Colorado ...... 46 Analysis of the Colorado cn-olite; The sources of corundum . . 47 Mining of corundum in the United States; The composition and properties of kaolin ............ 48 Localities of the large kaolin beds; Value of kaolin as an aluminium ore; Common clays .......... 49 Native sulphate of alumina; Deposits in New Mexico, Colorado and Ohio 50 Economic value of the aluminium sulphate deposits . . . .51 CONTENTS. XVIII

Chapter III

Physical Properties of Aluminium page Commercial aluminium not chemically pure; The most frequent impurities ...... 52 The influence of small amounts of impurities on the physical properties of the metal ............ -53 Analyses of commercial aluminium; Notes on the analyses . . .54 Recent analyses of present commercial metal ...... 55 Difference in the composition of metal made by the sodium and the electrolytic methods; The different conditions in which silicon exists in aluminium; Rammelsberg's analyses ...... 56 Absorption of gases by molten aluminium; Dumas' analyses; Author's observations; Le Verrier's detection of carbon in commercial aluminium .............. 57 Influence of carbon on the physical properties of alumiuium; Le Verrier detects nitrogen in commercial aluminium . . . . .58 Influence of nitrogen on the physical properties of aluminium; The color of pure and impure aluminium ....... 59 Tarnishing of aluminium in the air; Fracture of purest aluminium . 60 Fracture of impure aluminium; Hardness; Testing quality with the knife; Hardening by cold working ....... 61 Comparison of the hardness of aluminium with other metals; Specific gravity ............. 62 Influence of impurities ou the specific gravity; Increase of specific gravity by working .......... 63 Comparison of the specific gravity of aluminium and other metals . 64 Comparative value of equal weights and equal volumes of the different metals; Fusibilit}- ... ...... . . 65 Melting point determined by the electric pyrometer; Influence of impurities on the melting point; Volatilization; Odor . . . .66 Taste; Magnetism; Sonorousuess ........ 67 Sound produced by an aluminium bell, bar and tuning-fork; Aluminium sounding boards .......... 68 Velocity of sound in aluminium; Crystalline form; Elasticity . . 69 Tensile and compressive strength ........ 70 Table of tensile tests ........... 71 Table of compressive tests; Transverse tests ...... 72 General conclusions of Messrs. Hunt, Langley and Hall; Variation of tensile strength with the temperature .... .73 Influence of working and annealing on the mechanical properties; Tensile strength in comparison with weight .... 74 Comparison of the tensile strength with that of other metals, section for section and weight for weight; Malleability ... 7.5 CONTENTS.

XIX Thickness of aluminium leaf ; Color by transmitted light; Ductility . 76 Expansion by heat; Specific heat 77 Determinations of the specific heat by Regnault, Kopp, Mallet, Tomlinson, Naccari, Le Verrier ......... 78 Specific heat and latent heat of fusion as determined by Pionchon and the author .......... 79 The amount of heat in molten aluminium; Agreement with Dulong and Petit's law 80 Slow melting of aluminium due to its great latent heat of fusion; Comparison with other metals; Electric conductivity 81 Professor Dewar's determinations of the electric conductivity at very low temperatures; Conductivity for heat 82

Chapter IV

Chemical Properties of Aluminium. Atomic weight; Action of air . . . . , . . . .83 Resistance to air when melted ; Action of air and water together ; Piqures 84 Combustion of aluminium powder or leaf; Action of water . . .85 Decomposition of water by aluminium leaf; Action of hydrogen sulphide and sulphur 86 Experiment of the author with hydrogen sulphide and molten aluminium ............. 87 Action of sulphuric acid; Ditte's explanations ..... 88 Le Roy's quantitative tests with sulphuric acid . . . . .89 Action of nitric acid; Ditte's observations . . .... 90 Experiments of Le Roy, Lunge and the author on the action of nitric acid; Use of aluminium in the Grove battery; Action of hydrochloric acid .91 Action of hydrobromic, hydriodic and hydrofluoric acids; Experiment by the author; Action of organic acids, vinegar, etc 92 Action ofthe acids found in food; Deville's prediction ofthe usefulness of aluminium for culinary uteusils; Lubbert aud Roscher's experiments with thin foil 93 Ballaud's exhaustive tests with foods ; Rupp's results; Lunge and Schmid's experiments .......... 94 Details of Lunge and Schmid's tests ....... 95 Conclusions from these tests; Confirmation of these results by actual experience of two years with aluminium culinary utensils . . .96 Action of common salt, molten and in solution; Sea-water; Aluminium boats • CONTENTS.

XX PAGE Action of organic secretions, the saliva, etc 98 Action of caustic potash, caustic soda; Quantitative tests . . .99 Action of ammonia; Lime water; Solutions of metallic salts . . .100 Action of solutions of mercury, copper, silver, lead .... 101 Action of solutions of zinc, alkaline chlorides, aluminium salts; Action 102 of melted fluorspar; Use as a flux 101 Use of cryolite as a flux; Action of molten silicates and borates . . 103 Action of fused nitre; Purification of impure aluminium by nitre; Reaction with alkaline sulphates and carbonates 104 Reaction of aluminium on oxides of manganese, zinc, iron, lead, copper, barium . . . . . . . • • • • • .105 Greene and Wahl's process of producing pure manganese; Action of phosphate of lime, silver chloride, mercurous chloride, carbonic oxide, hydrogen, chlorine, bromine, iodine, fluorine ..... 106

Chapter V

Properties and Preparation of Aluminium Compounds. General considerations; Position of aluminium in the periodic classification of the elements .......... 107 Observations on the structure of aluminium compounds . . . 108 The tri-valency of aluminium; Aluminates ...... 109 Neutral salts of aluminium; Basic salts; General methods of formation of aluminium salts ........... 110 General properties of aluminium salts; Chemical reactions in solution; Reactions before the blowpipe ........ Ill Alumiuium oxide; Physical and chemical properties" .... 112 Hydrous aluminium oxides, natural and artificial; The soluble hydrate. 113 Aluminates; Potassium aluminate; Sodium aluminates; Barium aluminate 114 Aluminates of calcium, zinc, copper, magnesium, iron, beryllium; Aluminium chloride ........... 115 Hydrous aluminium chloride; aluminium-sodium chloride . . .116 Double chlorides of aluminium with phosphorus, sulphur, selenium, ammonium . . . . . . . . .117 Aluminium-chlor-sulphydride ; Alutninium-chlor-phosphydride ; Aluminium bromide; Aluminium iodide ....... 118 Aluminium fluoride; Methods of production ...... 119 Fluorhydrate of aluminium; Aluminium-hydrogen fluoride; Aluminium-sodium fluoride •■-....... 120 Aluminium sulphide; Double sulphides with sodium and potassium . 121 Use of aluminium sulphide in the laboratory for generating hydrogen sulphide; Aluminium selenide; Aluminium borides ....

CONTENTS. XXI PAGE Aluminium boro-carbides; Aluminium carbide ..... 123 Production of aluminium carbide iu the electric furnace by Le Verrier . 124 Composition and properties of aluminium carbide; Aluminium nitride 125 Aluminium sulphates, anhydrous and hydrous ..... 126 Basic aluminium sulphates ......... 127 Alums; Potash alum; Ammonia alum ....... 128 Soda alum; Double sulphates of aluminium and the metals; Aluminium selenites ............. 129 Aluminium nitrate; Aluminium antimonate; Aluminium phosphates . 130 Aluminium carbonate; Aluminium borate ...... 131 Hydrous aluminium borates; Aluminium silicates; Blast furnace slags 132

Chapter VI

Preparation of Aluminium Compounds for Reduction. The preparation of alumina; Preparation from alums or aluminium sulphate ............. 133 Preparation of alumina from ammonia alum ...... 134 Method used by Deville at Javel; Tilghman's method .... 135 Webster's process of making alumina from potash alum . . . 136 Preparation of alumina from bauxite; Method used at Salindres . . 137 Heating with soda and washing out the aluminate ..... 138 Apparatus used for washing; Precipitation of alumina by carbonic acid gas 139 Apparatus used for the precipitation; The barattes ..... 140 Washing and drying the precipitated alumina; Behnke's method of treating bauxite; Lieber's method ....... 141 Muller's method for extracting alumina from silicates; Use of common salt to decompose bauxite; Wagner's method of treating bauxite . 142 Laur's method of using sodium sulphate to decompose bauxite; Lowig's experiments on precipitating alumina from sodium aluminate solution; Dr. Bayer's improvements ........ 143 Preparation of alumina from cryolite; The dry way .... 144 Furnace for heating cryolite with chalk; Thomson's method . . 145 Conduct of the operation; Washing the fusion ..... 146 Production of the carbonic acid gas for precipitation .... 147 Composition of the precipitate; Action of steam on molten cryolite; Utilization of aluminous fluoride slags ....... 148 Utilization of the residual slags from sodium retorts by fusing with the aluminous slags; Decomposition of cryolite in the wet way . . 149 Method used by Deville at Javel; Modification of this process by Sauerwein 150 Reactions in Sauerwein's process; Weber's method of decomposing cryolite; Schuch's reaction .........

Contents

XXII PAGE Preparation of aluminium chloride and aluminium-sodium chloride . 152 Method used by Deville on a small scale at Javel . . . .153 Manufacture by Deville on a large scale I-5-* Furnace used and working of the operation ..•■■• 155 Output of the furnace; Purification of the crude chloride . . . 156 Deville's idea of making the double chloride; Margottet's description of the apparatus used at Salindres ....... 157 Conduct of the operation at Salindres 158 Cost of making the double chloride at Salindres 159 Plant of the Aluminium Company, Limited, at Oldbury, near Birmingham, England ........... 160 Arrangements of the furnaces and conduct of the operation . . . 161 Output of this plant; Purity of the double chloride .... 162 Castner's method of purifying the double chloride ..... 163 Cost of the purified double chloride; Gadsden's method of producing aluminium chloride; Count R. de Montgelas' improvement . . 164 Prof. Mabery's process for producing aluminium chloride in the electric furuace; Curie's method; Warren's general process for anhydrous metallic chlorides ........... 165 Camille A. Faure's process; Description by Berthelot .... 166 Details of Faure's process; Output claimed; Dullo's method of making aluminium chloride from clay ........ 167 Remarks on Dullo's suggestions; The preparation of aluminium fluoride and artificial cryolite .......... 168 Berzelius' method of making artificial cryolite; Deville's methods . 169 Pieper's reactions in the wet way; Bruner, Deville and Hautefeuille on making aluminium fluoride ......... 170 Grabau's processes; Aluminium fluoride from aluminium sulphate and fluorspar ............. 171 Aluminium fluoride indirectly and directly from kaolin . . . 172 Precautions necessary to obtain it free from iron ..... 173 The preparation of aluminium sulphide; Fremy's researches . . . 174 Purity of the aluminium sulphide produced ...... 175 Reichel's results; Experiments of the author ...... 176 Propositions of Comenge, Petitjean, etc. ....... 177 Lauterborn's patent anticipated ........ 178

Chapter VII

The Manufacture of Sodium. Relations of the production of sodium to the aluminium indvistry ; Isolation of sodium by Davy, Gay Lussac and Thenard, Curaudau . . 179 Briinner's apparatus; Donny and Mareska's condenser; Deville's improvements at Javel (1855) _ ]80 CONTENTS.

XXIII The chemical and pln-sical properties of sodium ..... 181 Method of reduction used at Javel; Composition of the mixtures for reduction 182 Utility of the different ingredients of the mixtures; Difficulties of condensing sodium vapor 183 Mixture used at La Glaciere and Nanterre; Charging the apparatus . 184 Description of retorts and condensers ; Manufacture in mercury bottles 185 The furnace used for manufacture in mercury bottles .... 186 Detailed description of condensers ........ 187 Conduct of the operation 188 Handling of the condensed sodium; The temperature necessary for reduction 189 Use of decarburized, cast-iron bottles; The continuous manufacture in cylinders 190 Furnace for manufacture in cylinders ....... 191 Arrangement of the cylinders in the furnace ...... 192 Charging and discharging the cylinders ....... 193 Tissier Bros. ' method of procedure at Rouen ...... 194 Furnace used by Tissier Bros. ......... 195 Charging and discharging Tissier's furnace ...... 196 Causes of loss of sodium; Deville's improvements at La Glaciere (1857) 197 Deville's large cylinder furnace; Difficulties in its operation . . . 198 Deville's attempts to use cast-iron retorts; Deville's improvements at Nanterre (1859) .... 199 Necessity of protecting the iron cylinders; Deville returns to smaller apparatus ............ 200 Cost of sodium at Salindres in 1S72; An experiment of Deville's in 1864; Wagner's method of preserving sodium ...... 201 Reduction of potassium and sodium compounds together; Thompson and White's method 202 Blackmore's process of reducing carbonate of soda; Thowless' apparatus; Jarvis' device for using fire-clay apparatus; Castner's process 203 History and principle of Castner's invention ...... 204 Reaction on which the process is based; Form of furnace used . . 206 Experimental furnace erected in England 207 Conduct of the operation in this furnace ....... 208 Yield of the furnace; Composition of the residues 210 Cost of sodium by the Castner process ....... 211 Erection of large works to operate the Castner process .... 212 Description of the largest furnaces 213 Manner of working and output of these furnaces 214 Preservation of the sodium ; Reactions in the process .... 215 Netto's sodium process; The Alliance Aluminium Company . . . 217 Details of Netto's apparatus .........

CONTENTS. XXIV PAGE Reduction of sodium compounds by electricity; Jablochaff 's apparatus; 219 Roger's method .....•••■■• "1" Details of Roger's experiments .....•••• 220 Grabau's observations on the electrolysis of molten sodium chloride . 222 Details of Grabau's electrolytic process; Castner's process of electrolyzing caustic soda ........... 223

Chapter VIII

The Reduction of Aluminium Compounds from the Standpoint of Thermal Chemistry.

The proper way to use the data of thermo-chemistry .... 226 Critical temperatures below which reactions do not occur . . . 227 Influence of physical state in determining a reaction; The heat of formation of some aluminium compounds ....... 228 The heat of formation of alumina compared with that of other oxides; Elements which reduce alumina easily ...... 229 Possibilities of the reduction of alumina ....... 230 Reduction of alumina by carbon; Necessary conditions to be fulfilled . 231 Heats of formation of chloride, bromide and iodide of aluminium, and other metals 232 Deductions as to the agents capable of reducing these aluminium salts 233 Heat of formation of aluminium fluoride and other metallic fluorides . 234 Observations on the reduction of aluminium fluoride; Heat of formation of aluminium sulphide and other metallic sulphides .... 235 Observations on the reduction of aluminium sulphide; Electricity as a reducing agent 236 The voltage necessary to produce decomposition of metallic fluorides, chlorides, oxides and sulphides; Tabular view of these data; Observations thereon ............ 237 Electrolysis of baths containing several ingredients; Illustration from Hall's process ............ 238 Illustration from Minet's process; The voltage required to decompose alumina at different temperatures . ....... 239 Calculation of the temperature at which hydrogen can begin to reduce alumina; The same calculation for carbon .... 240 Alumina has been reduced by carbon in an iron blast furnace; Peculiarity of acetylene gas as a reducing agent ... 241 Thermal aspect of other reactions used in the aluminium industry; The production of aluminium chloride from alumina . . 242 The production of aluminium sulphide from alumina; Peculiaritv of carbon bi-sulphide from a thermal standpoint . . .

CONTENTS. XXV

Chapter IX

Reduction of Aluminium Compounds by Means of Potassium or Sodium. PAGE Classification of methods ; The reduction of chlorine compounds ; Oersted's experiments (1824) . . . . . . . . 246 Wohler's experiments (1827); Wohler was repeating Oersted's work. 247 Wohler isolates aluminium as a metallic powder ; His experiments in 1S45 248 Globules of aluminium obtained by Wohler in 1845 .... 249 Impurity of Wohler's metal; Deville's experiments in 1854 . . . 250 Deville obtains pure alumiuium in ingots ...... 251 Deville's methods devised in his laboratory and applied at Javel (1S55). 252 Details of the apparatus employed; Conduct of the operation . . 253 Deville's dissatisfaction with this apparatus and its results . . . 255 Deville reduces aluminium chloride by sodium vapor .... 256 Deville's perfected process as used at Nanterre (1859) .... 257 Details of Deville's improvements ........ 258 Reduction in crucibles; Lining of crucibles ...... 259 Reduction on the bed of a reverberator}- furnace ..... 261 Deville's views on the aluminium industry in 1859 ..... 263 The Deville process as operated at Salindres in 18S2 .... 264 The chemical reactions in the process ....... 265 Description of furnace used and mode of operation .... 266 Cost of aluminium at Salindres; Niewerth's process .... 268 Gadsden's sodium vapor process; Frishmuth's claims .... 269 H. von Groussillier's improvement; The Deville-Castner process . . 270 Description of Castner's works; Conduct of the operations . . . 271 Efficiency of the process; Closing of these works ..... 273