CHEM Material Chemistry, Earth Resources and Introduction to Quality Management. -Inorganic Material Chemistry -Petroleum chemistry

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1 CHEM Material Chemistry, Earth Resources and Introduction to Quality Management Course content: -Metals and Metallurgy -Inorganic Material Chemistry -Petroleum chemistry -Quality management, intellectual property and green chemistry

2 Minerals and Metallurgy

3 Minerals Only a few minerals occur as pure elements in the earth s crust - Native Element Minerals Native sulfur Diamond Native silver Native copper Native gold

4 Beryl Quartz SiO 2 Calcite CaCO 3

5 Minerals -are naturally occurring, inorganic solids with well-defined chemical compositions and crystal structures In order for something to be classified as a mineral, it must meet the following criterion. Minerals are: (i) Naturally occurring, (ii) Inorganic, (iii) Have known chemical compositions (iv) Have definite physical properties (v) Are solid

6 Minerals are identified by common names Malachite is a copper carbonate hydroxide mineral, with the formula Cu 2 CO 3 (OH) 2

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8 Commercially, the most important sources of metals are; Oxide Sulfide Carbonate minerals

9 What is a Rock? Rocks are naturally occurring solid aggregates of different minerals

10 Ores Metal distribution in the earth depends on geologic processes that have taken place. Some processes may form minerals with high metal contents An ore is a mineral or aggregate of minerals from which a valuable constituent, especially a metal, can be profitably mined or extracted The value of an ore depends on, -how much metal is in the ore -how costly is it to remove the metal from the ore -depends on the demand of the metal

11 The occurrence and distribution of concentrated deposits of metals often play a role in international politics as nations compete for access to these materials

12 Many processes are used to obtain pure metal from ore. Some need to go through only a few steps, while other ores must go through many steps. Copper and gold were probably the first metals man learned to use. They occur in nature in a free state as well as in ores. Gold headband from BC

13 Metallurgy Metallurgy is the science and technology of extracting metals from their natural sources and preparing them for practical use. General metallurgical operations Mining Concentration of ore Conversion of ore into oxides Conversion of ore into free metals Purification of metal

14 1. Pyrometallurgy Metallurgical processes Extraction and purification of metals by processes involving the application of heat Some of the techniques used in pyrometallurgy are; (i) (ii) (iii) (iv) Calcination Roasting Smelting Refining

15 2. Hydrometallurgy Metal is extracted from its ore by use of aqueous reactions. 3. Electrometallurgy Processes that are used to reduce metal ore or refine metals, are based on electrolysis.

16 Colour Streak Luster Hardness Cleavage Fracture How to Identify Minerals: Physical Properties Specific Gravity Other Special Properties

17 Colour Minerals tend to occur in a range of colours, and color patterns help to identify them The most common elements affecting colour are: chromium, iron, manganese, titanium and copper.

18 Quartz comes in a wide range of colours. It is very easily colored by even trace amounts of impurities. colourless- clear purple quartz - amethyst yellow - citrine brown - smoky quartz pink - rose quartz. black - morion

19 Streak When minerals are scratched, the powder that is made by the scratch is called the streak. Sometimes the color of the streak can be used to identify the mineral. Eg. Haemetite a black mineral has a red streak. No other black mineral has a red streak.

20 Luster - describes the appearance of a mineral when light is reflected from its surface -Minerals can be termed: glassy, opaque, transparent, shiny, pearly, silky or most commonly: metallic and non-metallic.

21 Hardness Refers to "scratchability" or resistance to being scratched. Harder minerals will scratch softer minerals. Geologists rank minerals according to hardness using the Moh's scale He selected ten minerals and arranged them in order so that any one mineral could be used to scratch only minerals which are less.

22 Moh's Hardness Scale 1.0 TALC 2.0 GYPSUM 2.5 FINGERNAIL 3.0 CALCITE 3.5 COPPER PENNY 4.0 FLUORITE 5.0 APATITE 5.5 STEEL KNIFE BLADE/GLASS PLATE 6.0 ORTHOCLASE FELDSPAR 7.0 QUARTZ 8.0 TOPAZ 9.0 CORUNDUM (RUBY) 10.0 DIAMOND

23 Fingernail Hardness (2.5) Scratches Gypsum (2)

24 Cleavage... No cleavage

25 Specific Gravity Specific gravity is defined as the ratio of the weight of a substance compared to that of an equal volume of water Gravity separation, which relies on the difference in specific gravities of minerals, is one of the oldest techniques for separating minerals.

26 Magnetic Property -Magnetic properties are useful for identifying a mineral. -Several minerals react when placed within a magnetic field. Magnetism refers to the reaction of a mineral in a magnetic field. -Some minerals are strongly attracted to the magnet, others are weakly attracted, and some minerals are actually repelled.

27 Magnetic Property -The way a substance behaves in a magnetic field provides an important insight into the arrangements of its electrons. -Most minerals can be classified as; (i) Diamagnetic (ii) Paramagnetic (iii) Ferromagnetic -This is a piece of MAGNETITE with a magnet adhering to it

28 Ferromagnetic material An everyday example of ferromagnetism is a refrigerator magnet used to hold notes on a refrigerator door

29 Magnetism in Minerals 1. Diamagnetic - not attracted to a magnet (e.g., calcite, quartz, feldspar) 2. Paramagnetic - weakly attracted (e.g., Hematite, ilmenite); not permanent 3. Ferromagnetic - very strong attraction (metal iron); also permanent iron meteorite magnetite calcite

30 -Material is fed in through the top where a revolving cylinder carries it over a stationary magnet. Magnetic Separation -The magnetic field attracts and holds magnetic material and discharge the nonmagnetic material -The magnetic fraction is then released as it leaves the magnetic field. Non magnetic particles magnetic Nonmagnetic particles Nonmagnetic fracti fracti

31 Other Properties Characters Depending upon Senses Feel - What the mineral feels like. Ex. Graphite - greasy

32 Mineral Identification Basics CHEMICAL PROPERTIES REACTION TO HYDROCHLORIC ACID Calcite Reacts to HCl (*) Some minerals, notably the carbonates, react to cold dilute HCl. In this illustration a piece of CALCITE is shown to react (fizz) after HCl is applied. (*)

33 Pyrometallurgy The Pyrometallurgy of Iron Most important sources of iron are hematite Fe 2 O 3 and magnetite Fe 3 O 4. Reduction occurs in a blast furnace. The ore, limestone and coke are added to the top of the blast furnace.

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35 Formation of Steel -Most of the iron is used to manufacture steel -Steel is an alloy of iron -Iron from a blast furnace typically contains many undesired impurities

36 Hydrometallurgy The Hydrometallurgy of Aluminum Aluminum is the second most useful metal. Bauxite is a mineral that contains Al as Al 2 O 3.xH 2 O. Major impurities are silicates (SiO 2 ) and iron oxides (Fe 2 O 3 ).

37 Electrometallurgy Electrometallurgy is the process of obtaining metals through electrolysis. Two different starting materials: molten salt or aqueous solution

38 Electrometallurgy Electrometallurgy of Sodium Sodium is produced by electrolysis of molten NaCl in a Downs cell.

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40 Electrometallurgy Electrometallurgy of Aluminum -Al 2 O 3 melts at 2000 C and it is impractical to perform electrolysis on the molten salt. -Electrolysis cell is used to produce aluminum (Hall-Heroult process).

41 Electrometallurgy of Al

42 Electrometallurgy Electrorefining of Copper Because of its good conductivity, Cu is used to make electrical wires. Impurities reduce conductivity, therefore pure copper is required in the electronics industry.

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44 -Metals (impurities) are collected in the sludge at the bottom of the cell.

45 HW problem -Ni is one of the chief impurities in the crude Cu that is subjected to electrorefining. What happens to this Ni in the course of electrolytic process?

46 Economic Geology of Sri Lanka

47 Geological Survey and Mines Bureau (GSMB) in Sri Lanka is one of the responsible authorities for economic minerals in Sri Lanka.

48 Graphite

49 Bogala Graphite mine

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52 The Allotropes of Carbon Diamond Graphite Fullerenes Nano tubes

53 Graphite

54 Applications Pencils Brake linings Carbon brushes Crucibles & fire proof products

55 Applications Batteries

56 Apatite Apatites have the general formula, Ca 10 (PO 4 ) 6 X 2 or Ca 5 (PO 4 ) 3 X X = OH, F, Cl

57 Apatite Apatite is a group of phosphate minerals, usually referring to hydroxylapatite, fluorapatite and chlorapatite hydroxylapatite, fluorapatite chlorapatite Ca 5 (PO 4 ) 3 OH Ca 5 (PO 4 ) 3 F Ca 5 (PO 4 ) 3 Cl

58 Apatite in Sri Lanka -One of our best economic mineral reserves is the apatite rock phosphate at Eppawala. -It is situated around 20 km south of the ancient city of Anuradhapura and 150 km north east of Colombo. -The reserve extents over 7 km 2 and about 125 m deep from the surface.

59 Heavy Mineral Sands Heavy mineral sands are formed most usually in beach environments by concentration due to the specific gravity of the mineral grains. Beach sand deposits -Most common minerals in mineral sand are, Ilmenite All with specific gravity Rutile more Zircon Monazite than 2.9 Magnetite Garnet Cassiterite (oxide of tin)

60 Pulmoddai beach sand deposit is the most important mineral sand reserve in Sri Lanka to date. It contains minerals which consist of one of the most expensive and important metals in the world that is titanium. Ilmenite (FeTiO 3 ) and rutile (TiO 2 ) found in enormous concentrations in the Pulmoddai beach sand deposit.

61 This deposit extends from Nilaveli to Kokilai lagoon mouth.

62 Ilmenite (FeTiO 3 ) and rutile (TiO 2 )

63 Titanium Dioxide Titanium Dioxide is the most important white pigment currently produced commercially. The pigment is used in a wide The pigment is used in a wide range of applications including inks, textiles, paper, paints, food, and pharmaceuticals.

64 Rutile Anatase Brookite crystal structures of the three polymorphs of titanium dioxide, TiO 2

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67 2. Chloride process

68 Uses of TiO 2 / white pigments

69 Production of Ti

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71 Dolomite by-nc-nd: Il Topone / Emiliano B.

72 The Dolomites are a mountain range in Italy that is made of dolomite rock. Deodat de Dolomieu

73 Dolomite is composed of Calcium, Magnesium, and Carbonate [CaMg (CO 3 ) 2 ] and is classed as a carbonate.

74 Hard water causes scaling. by-nc-sa: Alan Penner Hard water can be improved by water softening treatment. by-nc: Nofolete / Dane Larsen by-nc: Dane Larsen by-nc-sa: spike55151