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The Preparation and Reactions of the Lower Chlorides and Oxychlorides of Silicon Joseph Bradley Quig Iowa State College

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The Preparation and Reactions of the Lower Chlorides and Oxychlorides of Silicon Joseph Bradley Quig Iowa State College Iowa State University Capstones, Theses and Retrospective Theses and Dissertations Dissertations 1926 The preparation and reactions of the lower chlorides and oxychlorides of silicon Joseph Bradley Quig Iowa State College Follow this and additional works at: https://lib.dr.iastate.edu/rtd Part of the Inorganic Chemistry Commons Recommended Citation Quig, Joseph Bradley, "The preparation and reactions of the lower chlorides and oxychlorides of silicon " (1926). Retrospective Theses and Dissertations. 14278. https://lib.dr.iastate.edu/rtd/14278 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]. INFORMATION TO USERS This manuscript has been reproduced from the microfilm master. UlVli films the text directly from the original or copy submitted. Thus, some thesis and dissertation copies are in typewriter face, while others may be from any type of computer printer. 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 bleedthrough, substandard margins, and impiroper alignment can adversely affect reproduction. In the unlikely event that the author did not send UMI 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. Oversize materials (e.g., maps, drawings, charts) are reproduced by sectioning the original, beginning at the upper left-hand corner and continuing from left to right in equal sections with small overiaps. ProQuest Information and Learning 300 North Zeeb Road, Ann Arbor, Ml 48106-1346 USA 800-521-0600 NOTE TO USERS This reproduction is the best copy available. UMI" THE PREPARATION AUD REACTIOHS OP THE LOVJER CHLORIDES AHD OXxCHLORIDES OP SILIG02? by Joseph. Bradley Qulg A Thesis Submitted to the Graduate Faculty for the Degree of DOCTOR OP PHILOSOPHY Major subject - Inorganic Chemistry Approved Signature was redacted for privacy. li ohBrge of MajS^Work Signature was redacted for privacy. Head of Major Department Signature was redacted for privacy. Dean of Graduate College Iowa State College 1926 UMI Number: DP14525 UMI UMI Microform DP14525 Copyright 2006 by ProQuest Information and Learning Company. All rights reserved. This microform edition is protected against unauthorized copying under Title 17, United States Code. ProQuest Information and Learning Company 300 North Zeeb Road P.O. Box 1346 Ann Arbor, Ml 48106-1346 ACKKOWLBDGMEKT Dhis occaaion is taken to acknowledge the kindly assist­ ance and encouragement given by Dr, John A, Wilkinson, Chem­ istry Department, Iowa State College, imder whose supervision the work reported here has been done. - 3 - TABLE OP COUTEBTS Page Part 1, « IBTRODUCTION . 7 A Camparlson of the Ealogen Derivatives of Silico- ethane 8 Review of Metliods for the Pa^eparation of Disilicon- HeKachloride . • 9 A STUDY OP TEE EFFECT OF THE VAPOR OP SILICON TETRACHLOR­ IDE Oil THE CHLORniATIOK OP 50?^ PERROSILICOK ....... 11 Description of the Process for the Preparation of Disilicon Hexachloride . .. ... , .14 Chlorination Apparatus i 15 Distillation Apparatus v ... 17 Optimum Amount of Silicon Tetrachloride Vapor . .19 Analysis of Disilicon Hexa.chloride . ... .19 Calculation of Yields ...20 Tat>le Showing Yields of Disilicon Hexachloride , » . 22 Curve Showing Yields of Lower Chlorides . ... 23 Summary ....... ...•••.•.......24 THE EPPECT OP SILICOH AHD 50^ PERROSILICON OH THE VAPOR OP SLLICOH TETRACHLORIDE AT THEIR CHLORIMTION TEMPER­ ATURES 25 Summary .............. ....28 THE SUBSTITUTIOU OP SILICON FOR 50% PERROSILICOH IE THE PROCESS FOR THE PREPARATION OP DISILICON HEXACHLORIDE , . 29 Tahle Showing Effect on Yield of Disilicon Hexa­ chloride .........31 Stmmiary 32 PROBABLE FUNCTIONS OP SILICON TETRACHLORIDE VAPOR IN THE PRESERVATION OP DISILICON HEXACHLORIDE 33 THE EMPLOYMENT OP CARBON TETRACHLORIDE VAPOR AS AN INERT CONSTITUENT IN THE CHLORINATION PROCESS ......... 38 Tahle Showing Effect on Yield of Disilicon Hexa­ chloride 42 Summary ......44 - 4 - Page THE STKUCTURE OF 50% FERROSILICOU 45 Phase Diagram of Perro^llicon 45 !i?h© Silicon Moleculo in 50^ Ferrosilicon 46 TEE EFFECT OF CATALYSTS OH THE CHLORIKATIOH TEMPER/iTURE OF 50^ FEHROSILICOH Ferric Cliloride as a Catalyst Wood Charcoal as a Catalyst ......w....* ^ Table Shov/ing Effect of Wood Charcoal on the Ghlor- ination of 50^ Ferroailicon ........... Stffiffiiary GEIIERAL SUI.JMAKY 51 COHCLUSIOK . ,. • . 53 Part II. IHTRODITCTIOH « . « . « * • . • . • . • 55 Historical Survey 56 Structural Foimilas of Silicon Ojsychlorides , . 57 Known Methods of Preparation of Silicon Oxy- chlorides 57 Theories for the Formation of Silicon Oxychlorides . 58 THE ACTION OF 0XIDI2IKG AGEIiTS OTHER THAH OXSTGEH OH Di- SILICOH HEXACHLORIDE 61 Introduction •.••*....• ...... .... 61 THE ACTION OF SULPHUR TRIOXIDE OH DISILICON IIEXACHLORIDE. 63 An Analytical Method for the Determination of the Silicon:Linkage 67 Analysis of a Hew Compound (2 Si2Clg*S03) ..... 69 Summary • 72 THE ACTION OP CHROMIUK TRIOXIDE OH DISILICOH HEXA­ CHLORIDE 73 Summary ......................75 THE ACTIOH OP OZOHE OH LIQUID DISILICOH HEXACHLORIDE . 76 Summary 80 - 5— Page TIIE ACTIOII OF OZOHE OH THE VAPOR OP DISILICOH HEXA- CHLORIDE . 81 Surama3?y 83 GENER^.L SmmMd OP THE ACTIOII OP 0XIDI2IHG AGENTS OTHER THAH OXyOElT OK DISILICOII HEXACHLORIDE * , . 84 THE ACTIOII OF OXTGEIT OK THE VAPOR OF DISILIGOH HEXA­ CHLORIDE * . 85 Tabulation of Results , , . „ . , 91 Sunimary . 92 A STUDST OF THE EFFECT OF OXyGEH OH THE LOlfER CltDORIDES OP SILIGOK DURIIIG THE CHLORINATIOE PROCESS 93 Tabulation of Results a « • 96 Summary 97 THE AGTIOH OF OXIGEH OIT SILICON TETRACHLORIDE AT 1850°C , 98 Isolation of Silicon Oxychloride from Commercial Silicon Tetrachloride 98 Preparation of Pure Silicon Tetrachloride . • , , . aOO Comparison of Yields of Silicon Oxychloride Ob­ tained "by Action of Oxygon on Silicon Tetra­ chloride at 1250°G . 103 Summary 104 GENERAL SmiKARY OP THE ACTION OP OXIDIZIUG AGEIITS ON DISILICOH HEXACHLORIDE 105 COHCLUSIOK a . 106 BIBLIOGRAPHY 107 •• 6 •• Part I A STlTDr OF TE32 OPTIMUM COITDITIOKS FOR THE PRESERVATION OP THE LOWER CHLORIDES OF SILICON IN THE CniGRINATION PROCESS - 7 - A..amy, M "m ofumm QommQm FOR THE PRESERVATION OP THE LOWER CHLORIDES OF SILICOH IK THE CHLORIHATIOH PROCESS INTRODUCTION Stock and Somieski (1916) showed that silicon possesses the power of atomic linkage to a limited degree toy their pre­ paration of the hydrosilicons SigiHg, SigHs, Si4H3^Q, Si^j^g, and 3l6Hi4, The existence of these linked silicon compounds reveals a field in the chemistry of silicon which has. scarcely heen explored. The reason for oiir meager knowledge of these compounds and their derivatives bears a definite relationship to the character of these compounds and to thei difficulties which have attended their preparation. The hy^osilicons them- selves are not suitable compotands for the investigation of the chemistry of compounds containing linlced sllic|3n atoms because they are spontaneously inflammable in air. j''; Some of the halogen derivatives of the hytkrosilicons have been prepared. Among these, the chlorine derivatives are the best known, TSQiile the preparation of the halogen derivatives . " • i-V. is accomplished v/ith much greater ease than th^i; corresponding hydrosilicons, a preliminary study shov^ed that |they are ob- tained in extremely small quantities by the knqwn methods of preparation. The chlorine derivative of silic<^ethane is the only one of these compounds which has been prepared in siif- ficient quantities to render it available for I'esearch on com­ pounds containing linked silicon atoms. That this chlorine - 8 - derivative is superior to the hydrosilicon itself for the study of compounds containing the silicon linkage, is shovm by a comr. parison of their physical properties in the following table. IVapor Pressure M.P,, "C B.P,, "C : sm. 760 ram. 760 mm. SigHg : 726(-15^7°) -132,5 •15 SigClg : 2.5(10®) 2,5 147 • A Comparison of the Chloro-derivative with Other Halogen Derivatives of Silicoethane: The chloro-derivative is the only halogen derivative of silicoethane vtiich is a liquid. The "bromine and iodine deri­ vatives are solids, Disilicon hexaiodide cannot be distilled at ordinary atmospheric pressure or in vacuo and its prepar­ ation from silicon tetraiodide is not adapted to the prepara­ tion of relatively large araoimts of the compound, Silicon tetraiodide is also difficult to prepare and hence the prepar­ ation of disilicon hexaiodide is rendered even more difficult. The fact that disilicon hexabromide depends on disilicon hexaiodide for its preparation, likewise removes it from the field at present as a starting point for the development of the chemistry of linked silicon ccanpotmds. Although disili­ con hexachloride may not show as much activity as the iodine derivative, because of the stronger bonding of the chlorine, workers in the field of silicon chemistry have selected it as the most accessible compound at the present time for the start­ 9 - ing point of their research on the chemistry of linked silicon compoimdSo Methods of Preparation of Disilicon Hexachlorid©; Disilicon
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