Also, cobalt and molybdenum are utilized as a catalyst in hydrodesulphurization of petroleum. In order to make liquid fuel, cobalt catalyst is used in the Fischer-Tropsch process. Several of them are discussed in this chapter. Scientists have performed several experiments on these catalysts. It is commonly known that salts and complexes of cobalt are catalysts for the selective oxidation of alkanes and selective epoxidation of alkenes. ![]() This shows that radioactive cobalt can be used as a tracer. Further, it is used for the treatment of deep-rooted tumors. Ĭobalt compounds which give blue color to glasses can also be made radioactive and can be used for treatment of some cancers. Important cobalt alloys and its uses are shown in Table 2. Cobalt oxides are utilized in ceramics as smalt, a cobalt potassium silicate. The most known minerals are linnaeite, Co 3 S 4 or ( CoNi) 3 S 4 smaltite, CoAs 2 or ( CoNi) As 2 and cobaltite, CoAsS. Important cobalt alloys and its uses are summarized in Table 2. Cobalt closely resembles nickel so that they are being identified as “twins.” Although cobalt is used in practice to plate iron, doing alloy is the most significant practice of cobalt. Ĭobalt is found together with iron, copper, nickel, silver and arsenic in nature. Two of these ions are 3+ and one of these ions was 2+. ( NO 3) 8 . 4 H 2 O . ( Hdartz − 3, 5 − diamino − 1, 2, 4 − triazole , was the most attractive of these that include three cobalt ions. It is known that all common cobalt compounds have octahedrally coordinated to nitrogen or oxygen ions, all of which include three cobalt ions, two of which are 3+ and one of which is 2+, similar to the title compound.Ĭo 3(1 − Hdatrz) . 6( H 2 O) 6. ![]() Both cobalt ions do not have amphoteric properties. In general, cobalt-II compounds dissolve in water however, CoS, CoCO 3, Co( OH) 2, Co( CN) 2 and CoC 2 O 4 are insolvables. It is more stable than those compounds which consist of cobalt-III ions. Ĭobalt generally forms cobalt(II) and cobalt(III) compounds, but there are cobalt compounds, which have 4 +, 1 +, 0, 1− oxidation states. All cobalt oxides dissolve in hydrochloric acid. Bare cobalt releases oxygen from acidic and neutral environment. But this ion can only be found in the complex. Īnother oxidation number of cobalt is +3. It is insoluble because it acquires passivity in concentrated nitrate and sulphuric acid. Other properties of cobalt are summarized in Table 1. Cobalt has the chemical configuration 4 s 23 d 7 and has oxidation states Co(II) and Co(III). ![]() In order to briefly discuss about cobalt chemistry in this section, we begin with cobalt electron configuration. This survey of the recent literature illustrates the fact that many different approaches on cobalt and new cobalt compounds are being used in many different areas. The studies carried out in this area so far have enabled and will be continued to be responsible for producing unknown and difficult reactions. This chapter aims to collect and summarize the chemical properties of cobalt and some new cobalt compounds. Global reserves of cobalt are approximately around 7 million tons. ![]() Cobalt is one of the abundant metals in the Earth. This is because of its unique properties such as a high-melting point (1493☌) and retaining its strength to a higher temperature, being ferromagnetic with high thermostability and multivalent. Nowadays, cobalt and cobalt compounds possess a variety of applications from industry to medicine. For example, Kumar and Garg synthesized cobalt(II) complexes of tetradentate Schiff bases of the type. īy 2000, scientists had carried out lots of experiments related to the synthesis of new cobalt compounds, examination of antibacterial properties of cobalt compounds and cobalt-catalysed reactions. They were used as the first electromagnet. Furthermore, aluminum-nickel-cobalt ( AlNiCo) magnets caused an important evolution in 1940. After 1900, a new corrosion resistant alloy was invented, which is referred to as Stellite. For instance, cobalt compounds were used to dyeing pottery by Egyptians and Babylonians in 1450BC. Cobalt was set apart from copper ore by Swedish chemist Georg Brandt in 1735. Glass, glazes and blue dyes for pottery were the oldest known uses of cobalt. The word cobalt is derived from the sixteenth century German term kobold.
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