Click here to load reader

Cyanide introduction by Jutharat

  • View
    521

  • Download
    6

Embed Size (px)

Text of Cyanide introduction by Jutharat

  1. 1. .4/2547 CYANIDE INTRODUCTION
  2. 2. 6 10400 0 2202 3616 0 2202 3606 1 2547 10 . / . -- : , 2546. 48 : : ; 30 . .4/2547 ISBN 974-91922-1-4
  3. 3. (CYANIDE INTRODUCTION)
  4. 4.
  5. 5. . . Dr. Terry Mudder
  6. 6. III IV V 1 1. 1 2. 2 3. 3 5 1. (Cyanide Species) 5 1.1 Free Cyanide 5 1.2 Simple Cyanide 6 1.3 Complex Cyanide 6 1.4 Total Cyanide 7 1.5 Cyanide Related Compound 7 2. 8 2.1 8 2.2 8 2.3 9 3. 10 3.1 Free Cyanide 10 3.2 Simple Cyanide 11 3.3 Complex Cyanide 11 4. 11 4.1 (Complexation) 11 4.2 (Precipitation) 11 4.3 (Adsorption) 12 4.4 (Oxidation) 12 4.5 (Thiocyanate) 12 4.6 (Volatilization) 12 4.7 (Biodegradation) 12 4.8 (Hydrolysis) 12
  7. 7. 13 1. 13 2. 13 2.1 13 2.2 14 2.3 Electrowining 14 2.4 Hydrolysis/Distillation 14 3. 15 3.1 Acidification/Voltilization/Reneutralization (AVR or Mills-Crowe process) 15 3.2 Metal Addition 16 3.3 Flotation 16 3.4 Solvent Extraction 17 4. 17 4.1 17 4.2 17 4.3 18 5. 18 5.1 Bio-Oxidation 18 5.2 Catalysis 20 5.3 Electrolysis 20 5.4 Chemical Addition 21 5.5 Photolysis 26 29 1. 29 1.1 29 1.2 30 2. 30 2.1 30 2.2 31 2.3 31 3. 32 4. 33 4.1 33 4.2 35
  8. 8. 5. 36 5.1 36 5.2 37 5.3 37 5.4 37 5.5 38 6. 38 6.1 38 6.2 39 7. 41 7.1 41 7.2 41 7.3 41 44 45 46 47 1. pH 5 2. 9 3. ATP 33 4. ATP 33 5. 34 6. 34 1. (Stability Constant: log K) 10 2. 32 3. 39
  9. 9. 1. (Newmont, Online 2002) (Cyanide) (Carbon: C) 1 (Nitrogen: N) 1 1,000 90 Glycine Methionine Methyl group donor (glycine) 4HCOHCNCOOHCHNH 222 + ++ 800 (Cyanogenic) Cyanoglycoside (Cyanogenesis) 0.217 0.006 0.007 12 (Cyanocobalamin : C63H88O14N14PCo) Laetrile ( ) Sodium Nitroprusside ()
  10. 10. 2. 18 J.C.Dippel H.Diesbach Potassium Carbonate Green Vitrol (Iron Sulfate) Berlin Blue Prussian Blue 1782 Karle Scheele Prussian Blue Berlin Blue acid Prussian acid Hydrogen Cyanide Karle Scheele Cyanide Kyanos 4 Karle Scheele (Sodium Cyanide) 1834 Prussian Blue Sodium Carbonate (Tamura, Online 2002) 3 Dupont (USA), Degussa (Germany) ICI (England) (MacDonald, Online 2002) Blausure-Methane-Ammoniak Process 234 3HHCNNHCH + Shawinigan Process 2833 7H3HCNHC3NH ++ Shawinigan Process (By product) Acrylonitrile 23% Andrussaw Process O3HHCN1.5OCHNH 2 Pt 243 +++ 77%
  11. 11. (Sodium Cyanide: NaCN) 2 (Sodium Carbonate : Na2CO3) (Carbon: C) (Ammonia: NH3) (Sodium Hydroxide : NaOH) (Sodium Amide : NaNH2) (Sodium Chloride : NaCl) (Calcium Cyanamide : CN2Ca) 3. 1.4 13% 87% (Steel Hardening) (International Cyanide Management Code, Online 2002) (Gravity Process) (Amalgamation) 60% (Chlorination) Bromine Thiourea Thiosulfate Thiocyanate Organic Nitrile Malononitrile Aqua Regia (Hydrochloric+Nitric) Selenic Acid (H2SeO4) (Kuzugudenli et. al., Online 1999)
  12. 12. 1806 Hagen 1887 J.S.MacArthur 100 Elsners equation ++++ 4OH4Au(CN)O2HO8CN4Au 222 90% (Cyanidation) 90% (Total Cyanide) Pre-Treatment Bio-Oxidation (Bioleaching) Bio-Oxidation Pre-Treatment (Avraamides, 1982:374-378; Utah Mining Association, Online 2001)
  13. 13. 1. 1 1 5 1.1 Free Cyanide (Moran, Online 2000) Free Cyanide (Cyanide ion: CN- ) (Hydrogen cyanide: HCN) (aq)HCNHCN + + (g)(aq) HCNHCN pH 9.3-9.5 pH 11 99% pH 7 99% : Botz (2001) 1 pH
  14. 14. 1.2 Simple Cyanide (Barnes et. al., Online 2000) Simple Cyanide 2 1.2.1 Soluble Simple Cyanide Complex Soluble Simple Cyanide Complex 1 2 (Sodium Cyanide: NaCN), (Potassium Cyanide: KCN), (Calcium Cyanide: Ca (CN)2) (Mercury Cyanide: Hg(CN)2) Free Cyanide 1.2.2 Insoluble Simple Cyanide Complex Insoluble Simple Cyanide Complex (Zinc Cyanide: Zn(CN)2), (Copper Cyanide: CuCN), (Nickel Cyanide: Ni(CN)2) (Silver Cyanide: AgCN) 1.3 Complex Cyanide (Barnes, Online 2000) Complex Cyanide 3 (Dissociation) 1.3.1 Weak Acid Dissociable Cyanide Weak Acid Dissociable Cyanide (WAD Cyanide) Zn(CN)4 2- , Cd(CN)4 2- Cd(CN)3 - 1.3.2 Moderately Strong Acid Dissociable Cyanide Moderately Strong Acid Dissociable Cyanide Cu(CN)2 - , Cu(CN)3 2- , Ni(CN)4 2- Ag(CN)2 - 1.3.3 Strong Acid Dissociable Cyanide Strong Acid Dissociable Cyanide (SAD Cyanide) Fe(CN)6 4- , Fe(CN)6 3- , Co(CN)6 4- Au(CN)2 -
  15. 15. Hexacyanoferrate (II) ion [Fe (CN)6 4- ] Hexacyanoferrate (III) ion [Fe(CN)6 3- ] Free Cyanide ++ CNO]H[Fe(CN)OHFe(CN) 2 252 3 6 + +++ 3(s)2 2 25 3H5CNFe(OH)OHO]H[Fe(CN) (Double Metallocyanide Complex) 6(s)2 24 6 Fe(CN)M2MFe(CN) + + K3Fe(CN)6 Cu3Fe(CN)6 1.4 Total Cyanide Total Cyanide (Cyanate: CNO- ) (Thiocyanate: SCN- ) 1.5 Cyanide Related Compound 1.5.1 Cyanate (CNO- ) Cyanate (Oxidizing Reagent) (Chlorine: Cl2), (Hypochlorite: ClO- ), (Ozone: O3) (Hydrogen Peroxide: H2O2) (Hydrolyze) (Ammonia: NH3) (Carbon Dioxide: CO2) 1.5.2 Thiocyanate (SCN- ) Thiocyanate (Cyanide) (Thiosulphate) (Sulfide ion)
  16. 16. 7 (Oxidize) (Carbonate: CO3 2- ), (Sulfate: SO4 2- ) (Ammonia: NH3) 1.5.3 Cyanogen Chloride (ClCN) Cyanogen Chloride (Intermediate Compound) 1.5.4 Chloramine (NH2Cl) Chloramine Alkaline Chlorination 1.5.5 Cyanogen (NC-CN) Cyanogen (Oxidizing Reagent) 1.5.6 Nitrate Ammonia (Nitrate: NO3 - ) (Ammonia: NH3) 2. 25 Free Cyanide, Simple Cyanide Complex Cyanide (Meehan, Online 2000) 2.1 Complex cyanide Metallo Cyanide Alkaline Cyanide Alkaline Metallic Cyanide Double Metallic Cyanide Turnbulls blue Fe3[Fe(CN)6]2 Prussian Blue Fe4[Fe(CN)6]3 pH Anoxic Condition 2.2 Free Cyanide, Simple Cyanide Complex Cyanide pH Redox Potential pH 9.2
  17. 17. : Meehan (2000) 2 Reducing Condition Oxidizing Condition (Iron Cyanide: Fe(CN)6total) Reducing Condition 2.3
  18. 18. 3. (Dissociation Constant) - (pH) 3.1 Free Cyanide Free Cyanide 100% 1 (Stability Constant: log K) (log K) Hexacyanocobaltate [Co(CN)6]3- 64.0 Hexacyanoferrate(III) [Fe(CN)6]3- 43.6 Mercurycyanide [Hg(CN)4]2- 41.4 Hexacynoferrate(II) [Fe(CN)6]4- 35.4 Tetracyanonickelate [Ni(CN)4]2- 31.8 Tetracyanocuprate [Cu(CN)4]3- 30.3 Tricyanocuprate [Cu(CN)3]2- 23.5 Dicyanoargenate [Ag(CN)2]- 21.0 Dicyanocuprate [Cu(CN)2]- 18.8 Tetracyanozincate [Zn(CN)4]2- 16.9 Tetracyanocadmiate [Cd(CN)4]2- 16.8 Zinc Cyanamide Zn(CN)2 11.1 Cadmium Cyanide Cd(CN)2 11.0 Hexacyanomanganate [Mn(CN)4]3- 9.7 Hydrogen Cyanide HCN 9.2 Zinc Cyanide ZnCN+ 5.3 : U.S.EPA (1994) Meehan (2000)
  19. 19. 3.2 Simple Cyanide Simple Cyanide 3.3 Complex Cyanide Complex Cyanide Weak Acid Dissociable Cyanide Moderately Strong Acid Dissociable Cyanide Strong Acid Dissociable Cyanide 4. (International Cyanide Management Code, Online 2002) 4.1 (Complexation) Zn(CN)4 2- , Cd(CN)4 2- , Cd(CN)3 - , Cu(CN)2 - , Cu(CN)3 2- , Ni(CN)4 2- Ag(CN)2 - 4.2 (Precipitation) (Iron Cyanide) (Double Metallocyanide Complex) Cu2Fe(CN)6, Ni2Fe(CN)6, Zn2Fe(CN)6 Fe4[Fe(CN)6]3
  20. 20. 4.3 (Adsorption) 4.4 (Oxidation) Strong Oxidizing Agent 4.5 (Thiocyanate) 4.6 (Volatilization) pH , 4.7 (Biodegradation) (Aerobic Condition) (Anaerobic Condition) 4.8 (Hydrolysis) (Formic Acid) (Ammonium Formate) (Aerobic Condition)
  21. 21. (Cyanide Treatment) 2 (Young, Online 2002) (Destruction Process) (Recovery Process) (Destruction Process) (Recovery Process) 1. (Natural Degradation) Hydrolysis Photodegradation, Chemical Biological Oxidation pH 2. 2.1 (Dilution)
  22. 22. 2.2 (Membrane) 2 2.2.1 Electrodialysis Electrodialysis 2.2.2 Reverse Osmosis Reverse Osmosis 2.3 Electrowining Electrowining SAD Cyanide WAD Cyanide + ++ CNMeM(CN) Steel Wool pH 2.4 Hydrolysis / Distillation Conventional Absorption Scrubbing Tower WAD SAD Cyanide (aq)HCNHCN + + (g)(aq) HCNHCN
  23. 23. 3. 3.1 Acidification/Volatilization/Reneutralization (AVR or Mills- Crowe Process) AVR or Mills-Crowe Process (Recovery) (Acidification) pH 8.0 WAD Cyanide (Volatilization) pH MHCNHMCN (g) ++ ++ (Sodium Hydroxide: NaOH) 70-95% (Slurry) ++ 2 4(aq)42 SO2HCNSOH2CN (g)(aq) HCNHCN OHNaCNNaOHHCN 2(g) ++ Acidification - (Reneutralization) (Metal Hydroxide) (s)MOHOHM + + (Sulphuric Acid: H2SO4) Acidification (Calcium Hydroxide: Ca(HO)2) (s)24 2 4 2 O2HCaSOSOCa O2H + + (Nitric acid: HNO3) (Sodium Hydroxide: NaOH) Recovery (Sodium Sulphide: NaS2) (Copper Sulphide: Cu2S)
  24. 24. 3.2 Metal Addition SAD complex Fe2+ Fe3+ Hexacyanoferrate (II) ion [Fe(CN)6 4- ] Hexacyanoferrate (III) ion [Fe(CN)6 3- ] (Photodegradation) Hexacyanoferrate (II) ion [Fe(CN)6 4- ] 6(s)2 24 6 Fe(CN)M2MFe(CN) + + Hexacyanoferrate (III) ion [Fe(CN)6 3- ] Hexacyanoferrate (III) ion Hexacyanoferrate (II) ion (Sodium Sulphite: Na2SO3) (Sodium Disulphite: NaHSO3) Reducing Agent Zn Cu pH 5-7 3.3 Flotation Flotation 1880 Flotation SAD Cyanide Flotation Heteropolar Surfactant Cationic Amine Tricaprylmethyl Ammonium Chloride (R4NCl) Anionic SAD Cyanide ++ x)Cl-(yM(CN)N)(RM(CN)NClx)R-(y 6(s)x-y4 x-y x4 SAD Cyanide WAD Cyanide
  25. 25. 3.4 Solvent Extraction Solvent Extraction 1950 10 Solvent Extraction Solvent Extraction Solvent Extraction Flotation Solvent Extraction 4. (Adsorption method) 4