Metallurgy and the Chemistry of Metals PDF

Metallurgy and the Chemistry of Metals 1...

Metallurgy and the Chemistry of Metals 1 Copyright © McGraw-Hill Education. All rights reserved. No reproduction or distribution without the prior written consent of McGraw-Hill Education.  Metallurgy A mineral is a naturally occurring substance with a range of chemical compositions. An ore is a mineral deposit concentrated enough to allow economical recovery of a desired metal. An alloy is a solid solution either of two or more metals, or of a metal or metals with one or more nonmetals. Metallurgy is the science and technology of separating metals from their ores and of compounding alloys. Recovery of a metal from its ore: 1. Preparation of the ore 2. Production of the metal 3. Purification of the metal 2  Principal Types of Minerals Copyright © McGraw-Hill Education. Permission required for reproduction or display. Table 21.1 Principal Types of Minerals Type Minerals Uncombined metals Ag, Au, Bi, Cu, Pd, Pt Carbonates BaCO3 (witherite), CaCO3 (calcite, limestone), MgCO3 (magnesite), CaCO3 ∙ MgCO3 (dolomite), PbCO3 (cerussite), ZnCO3 (smithsonite) Halides CaF2 (fluorite), NaCl (halite), KC1 (sylvite), Na3 AlF6 (cryolite) Oxides A12 O3 ∙ 2H2 O (bauxite), A12 O3 (corundum), Fe2 O3 (hematite), Fe3 O4 (magnetite), Cu2 O (cuprite), MnO2 (pyrolusite), SnO2 (cassiterite), TiO2 (rutile), ZnO (zincite) Phosphates Ca3 (PO4 )2 (phosphate rock), Ca5 (PO4 )3 OH (hydroxyapatite) Silicates Be3 Al2 Si6 O18 (beryl), ZrSiO4 (zircon), NaAlSi3 O8 (albite), Mg 3 (Si4 O10 )(OH)2 (talc) Sulfides Ag 2 S (argentite), CdS (greenockite), Cu2 S (chalcocite), FeS2 (pyrite), HgS (cinnabar), PbS (galena), ZnS (sphalerite) Sulfates BaSO4 (barite), CaSO4 (anhydrite), PbSO4 (anglesite), SrSO4 (celestite), MgSO4 ∙ 7H2 O (epsomite) 3 Metals and Their Best-Known Minerals manganese nodules 4  Preparation of the ore Flotation: separation of clay and silicate materials (gangue) from the ore Amalgamation: combining 2 materials, e.g. Hg can amalgamate gold Magnetism: e.g. magnetite 5 https://www.sciencephoto.com/media/10104 47/view/magnet-separating-iron-from-sand  Production of Metals Roasting CaCO3 𝑠 ⟶ CaO 𝑠 + CO2 (𝑔) 2PbS 𝑠 + 3O2 𝑔 ⟶ 2PbO 𝑠 + 2SO2 (𝑔) Chemical Reduction TiCl4 𝑔 + 2Mg 𝑙 ⟶ Ti 𝑠 + 2MgCl2 (𝑙) Cr2 O3 𝑠 + 2Al 𝑠 ⟶ 2Cr 𝑙 + Al2 O3 𝑠 WO3 𝑠 + 3H2 𝑔 ⟶ W 𝑠 + 3H2 O 𝑔 Electrolytic Reduction 2MO 𝑙 ⟶ 2M at cathode + O2 at anode 2MCl 𝑙 ⟶ 2M at cathode + Cl2 at anode 6  Blast Furnace for Producing Iron (Reduction Process) 7 Steel Manufacturing via the Oxygen Process (Oxidation Process) 8  Types of Steel Copyright © McGraw-Hill Education. 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Table 21.3 Types of Steel C Mn P S Si Ni Cr Others Composition Compositio Compositio Compositio Composition Composition Composition Composition Type Uses (Percent by n (Percent n (Percent n (Percent (Percent by (Percent by (Percent by (Percent by Mass)* by Mass)* by Mass)* by Mass)* Mass)* Mass)* Mass)* Mass)* Sheet Cu (0.2 Plain 1.35 1.65 0.04 0.05 0.06 — — products, − 0.6) tools Constructi High- Cu (0.01 0.25 1.65 0.04 0.05 0.15 − 0.9 0.4 − 1.0 0.3 − 1.3 on, steam strength − 0.08) turbines Kitchen 0.04 utensils, Stainless 0.03 − 1.2 1.0 − 10 0.03 1−3 1 − 22 4.0 − 27 — − 0.06 razor blades 9  Purification of Metals Distillation 70℃ Ni 𝑠 + 4CO 𝑔 Ni(CO)4 (𝑔) 200℃ Ni(CO)4 𝑔 Ni 𝑠 + 4CO (𝑔) Electrolysis Cu 𝑠 impure ⟶ Cu2+ 𝑎𝑞 + 2𝑒 − Cu2+ 𝑎𝑞 + 2𝑒 − ⟶ Cu 𝑠 (pure) Zone refining 10 Zone Refining of Metals Metal rod Heating coil 11  Band Theory of Conductivity In band theory of conductivity, delocalized electrons move freely through “bands” formed by overlapping molecular orbitals. Mg 1𝑠 2 2𝑠 2 2𝑝6 3𝑠 2 or Ne 3𝑠 2 ← 𝑒− → 12 Energy Gaps Between Valence and Conduction Bands in Metals, Semiconductors, and Insulators e- e- 13  Semiconductors: Doping Si Ne 3𝑠 2 3𝑝2 n-type semiconductor p-type semiconductor donor impurities acceptor impurities P Al Ne 3𝑠 2 3𝑝3 Ne 3𝑠 2 3𝑝1 14  Trends in Metallic Character Increasing Metallic Character Increasing Metallic Character 15  Alkali Metals Copyright © McGraw-Hill Education. Permission required for reproduction or display. Table 21.4 Properties of Alkali Metals Li Na K Rb Cs Valence electron configuration 2𝑠1 3𝑠1 4𝑠1 5𝑠1 6𝑠1 Density gΤcm3 0.534 0.97 0.86 1.53 1.87 Melting point (°C) 179 97.6 63 39 28 Boiling point (°C) 1317 892 770 688 678 Atomic radius (pm) 152 186 227 248 265 Ionic radius (pm)* 78 98 133 148 165 Ionization energy kJΤmol 520 496 419 403 375 Electronegativity 1.0 0.9 0.8 0.8 0.7 Standard reduction potential V † -3.05 -2.71 -2.93 -2.93 -2.92 Halite: NaCl 16 https://giphy.com/gifs/digg-boom-explosions-w9ZhgoozBZg2Y/links  Trends in Metallic Character Increasing Metallic Character Increasing Metallic Character 18  Alkaline Earth Metals Copyright © McGraw-Hill Education. Permission required for reproduction or display. Table 21.5 Properties of Alkaline Earth Metals Be Mg Ca Sr Ba Valence electron configuration 2𝑠 2 3𝑠 2 4𝑠 2 5𝑠 2 6𝑠 2 Density gΤcm3 1.86 1.74 1.55 2.6 3.5 Melting point (°C) 1280 650 838 770 714 Boiling point (°C) 2770 1107 1484 1380 1640 Atomic radius (pm) 112 160 197 215 222 Ionic radius (pm)* 34 78 106 127 143 First and second ionization 899 738 590 548 502 energies kJΤmol 1757 1450 1145 1058 958 Electronegativity 1.5 1.2 1.0 1.0 0.9 † Standard reduction potential V -1.85 -2.37 -2.87 -2.89 -2.90 Dolomite: MgCO3 ∙ CaCO3 19  Aluminum Impure Al2 O3 𝑠 + 2OH − 𝑎𝑞 ⟶ 2AlO2− 𝑎𝑞 + H2 O (𝑙) AlO2− 𝑠 + H3 O+ 𝑎𝑞 ⟶ Al OH 3 (𝑠) Δ 2Al OH 3 𝑠 → Al2 O3 𝑠 + 3H2 O (𝑔) Hall process Cryolite (Na3AlF6) Anode: 3[2O2− ⟶ O2 𝑔 + 4e− ] Cathode: 4[Al3+ + 3e− ⟶ Al (𝑙)] 21 2Al2 O3 ⟶ 4Al 𝑙 + 3O2 (𝑔) Aluminum 22  Aluminum Thermite reaction https://www.thefirearmblog.com/blog/2019/02/13/behind-the-scenes-of-hollywood- 23 weapons-breaking-terry-badly/ Chemistry In Action: Recycling Aluminum Collecting Purifying 25