TABLE OF CONTENTS
CONTENTS PAGE
Title Page – – – – – – – – i
Certification – – – – – – – ii
Dedication – – – – – – – – iii
Acknowledgements – – – – – – iv
Table of Contents – – – – – – – vi
CHAPTER ONE
- INTRODUCTION – – – – – 1
CHAPTER TWO
- NICKEL AND ITS PROPERTIES – – – 5Atomic and Physical properties – – – – 5Isotope – – – – – – – 6Occurrence – – – – – – – 9
- Compounds of Nickel – – – – – 11
- Nickel (0) – – – – – – – 11
- Nickel (I) – – – – – – – 11
- Nickel (II) – – – – – – – 12
- Nickel (III) and (IV) – – – – – 14
- Compounds of Nickel – – – – – 11
CHAPTER THREE
- COINAGE OF NICKEL – – – – 16
- Production of Nickel – – – – – 17
- Electrorefining – – – – – – 18
- Mond Process – – – – – – 19
- Metal value – – – – – – – 20
- Application of Nickel – – – – – 22
- Biological Role of Nickel – – – – 25
- Toxicity of Nickel – – – – – – 28
- Production of Nickel – – – – – 17
CHAPTER FOUR
- SUMMARY AND CONCLUSION – – – 32
- Summary – – – – – – – 32
- Conclusion – – – – – – – 33
References
CHAPTER ONE
- INTRODUCTION
Nickel is a nutritionally essential trace metal for at least several animal species, micro-organisms and plants,and therefore either deficiency or toxicity symptoms can occur when, respectively, too little or too much Ni is taken up. Although a number of cellular effects of nickel have been documented, a deficiency state in humans has not been described (Barceloux, 1999). Nickel and nickel compounds have many industrial and commercial uses, and the progressof industrialization has led to increased emission of pollutantsinto ecosystems. Although Ni is omnipresent andis vital for the function of many organisms, concentrationsin some areas from both anthropogenic release and naturally varying levels may be toxic to living organisms(Scott-fordsmand, 1997).
Nickel is a chemical element with the symbolNi and atomic number 28. It is a silvery-white lustrous metal with a slight golden tinge. Nickel belongs to the transition metals and is hard and ductile. Pure nickel, powdered to maximize the reactive surface area, shows a significant chemical activity, but larger pieces are slow to react with air under standard conditions because an oxide layer forms on the surface and prevents further corrosion (passivation). Even so, pure native nickel is found in Earth’s crust only in tiny amounts, usually in ultramafic rocks, and in the interiors of larger nickel–iron meteorites that were not exposed to oxygen when outside Earth’s atmosphere (Anthonyet al., 1990).
Use of nickel (as a natural meteoric nickel–iron alloy) has been traced as far back as 3500 BCE. Nickel was first isolated and classified as a chemical element in 1751 by Axel Fredrik Cronstedt, who initially mistook the ore for a coppermineral, in the cobalt mines of Los, Hälsingland, Sweden. The element’s name comes from a mischievous sprite of German miner mythology, Nickel (similar to Old Nick), who personified the fact that copper-nickel ores resisted refinement into copper. An economically important source of nickel is the iron ore limonite, which often contains 1–2% nickel. Nickel’s other important ore minerals include pentlandite and a mixture of Ni-rich natural silicates known as garnierite. Major production sites include the Sudbury region in Canada (which is thought to be of meteoric origin), New Caledonia in the Pacific, and Norilsk in Russia.
