Cobalt Reserves

Cobalt reserves (known ore bodies that may be worked) in the world are estimated to 3.2 milKon tonnes (cobalt content) [30.4]. An estimate of the reserve base (known ore bodies that may be worked at some future time) gave 10 million tonnes, of which the DRC accounts for 25%. Most of this large reserve base is in nickel-bearing laterite deposits and in sedimentary copper deposits of DRC and Zambia. In addition millions of tonnes of speculative cobalt resources exist in manganese nodules on the ocean floor. 

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The world s largest cobalt reserves are iu Zaire, Zambia, Morocco, Canada, and AustraUa. Together the ores of these countries contain well over one-half of the world cobalt supply. The richest deposits are iu Zaire and Zambia. The reserves of Canada and AustraUa comprise approximately one-fourth of the world supply. Smaller but commercially practical ore bodies also exist iu Russia, Einland, Uganda, and the Philippines. 

What about the supply of cobalt Irrespective of where the cobalt reserves are located, today and in the near future, a significant portion of the world primary cobalt is still produced from the Cu-Co deposits of Central Africa, the remainder originating from Ni laterites and Ni-Co sulphides and sulpho-arsenide ores (Morocco, Sudbury, Norils k, Australia). 

In Moroccan deposits, cobalt occurs with nickel in the forms of smaltite, skuttemdite, and safflorite. In Canadian deposits, cobalt occurs with silver and bismuth. Smaltite, cobaltite, erythrite, safflorite, linnaeite, and skuttemdite have been identified as occurring in these deposits. AustraUan deposits are associated with nickel, copper, manganese, silver, bismuth, chromium, and tungsten. In these reserves, cobalt occurs as sulfides, arsenides, and oxides. 

More than 200 ores are known to contain cobalt but only a few are of commercial value. The more important are arsenides and sulfides such as smaltite, C0AS2, cobaltite (or cobalt glance), CoAsS, and linnaeite, C03S4. These are invariably associated with nickel, and often also with copper and lead, and it is usually obtained as a byproduct or coproduct in the recovery of these metals. The world s major sources of cobalt are the African continent and Canada with smaller reserves in Australia and the former USSR. All the platinum metals are generally associated with each other and rhodium and iridium therefore occur wherever the other platinum metals are found. However, the relative proportions of the individual metals are by no means constant and the more important sources of rhodium are the nickel-copper-sulfide ores found in South Africa and in Sudbury, Canada, which contain about 0.1% Rh. Iridium is usually obtained from native osmiridium (Ir 50%) or iridiosmium (Ir 70%) found chiefiy in Alaska as well as South Africa. 

Another issue with metals is availability. For example, cobalt is not produced in the United States, but it used extensively in a wide variety of alloys and in the production of one of the most common types of lithium batteries. The availability of cobalt is crucial to several segments of American industry. For example, batteries being developed for use in automobiles powered by alternate energy sources are currently envisioned to use a lithium ion battery that also contains cobalt. However, cobalt is not the only strategic metal, and there is concern about the availability of several metals that are vital to industries in the United States, China, and Japan. There will be competition and stockpiling of strategic metals as the reserves become less accessible. 

Terephthalic acid is commonly abbreviated TA or TPA. The abbreviation PTA (P = pure) is reserved for the product of 99% purity for polyester manufacture. For many years polyesters had to be made from dimethyl terephthalate (DMT) because the acid could not be made pure enough economically. Now either can be used. TA is made by air oxidation of /7-xylene in acetic acid as a solvent in the presence of cobalt, manganese, and bromide ions as catalysts at 200°C and 400 psi. TA of 99.6% purity is formed in 90% yield. This is called the Amoco process. 

Carbonylation of methanol to form acetic acid has been performed industrially using carbonyl complexes of cobalt ( ) or rhodium (2 ) and iodide promoter in the liquid phase. Recently, it has been claimed that nickel carbonyl or other nickel compounds are effective catalysts for the reaction at pressure as low as 30 atm (2/4), For the rhodium catalyst, the conditions are fairly mild (175 C and 28 atm) and the product selectivity is excellent (99% based on methanol). However, the process has the disadvantages that the proven reserves of rhodium are quite limited in both location and quantity and that the reaction medium is highly corrosive. It is highly desirable, therefore, to develop a vapor phase process, which is free from the corrosion problem, utilizing a base metal catalyst. The authors have already reported that nickel on activated carbon exhibits excellent catalytic activity for the carbonylation of... 

We should conserve and recycle metals whenever possible because it is far cheaper to produce metals from recycled products than from ore. Environmentally sound exploration of new reserves is also required. Ore nodules discovered on the ocean floor, for example, contain as much as 24 percent manganese and 14 percent iron. Significant quantities of copper, nickel, and cobalt have also been found in this submarine terrain. Perhaps mining of the ocean floor may one day replace the mining we now do on land. And in the not too distant future, perhaps the mining of metal-rich asteroids in space will become a reality. 

The cobalt (II) carbonate prepared as above is dissolved in a hot mixture of 70 ml. of glacial acetic acid and 140 ml. of water. This solution is then added to a cold solution of 105 g. of sodium nitrite (1.52 mols) in 500 ml. of concentrated ammonia contained in a 2-1. Erlenmeyer flask. The resulting mixture is well cooled in ice and 280 ml. of 3% H202 is slowly added with good swirling. The flask is then allowed to remain 20 minutes longer in the ice bath and 3.5 g. of activated charcoal is added. The mixture is next heated for 1 hour over a free flame (in the hood, as much ammonia escapes) and the volume is kept constant by the addition of water as necessary. The hot liquid is filtered rapidly by suction to remove the charcoal, and the filtrate is cooled in an ice-water mixture. The product that separates (crystallization is aided by scratching the walls of the container) is suction filtered, the filtrate reserved for further workup, and the solids washed with ethanol and ether and then air-dried. 

The reaction of diethyl zinc with water produces zinc oxide, and then zinc carbonate, as the alkaline reserve. These chemicals have antiseptic properties which may also prevent the growth of mold in paper. They may also improve the brightness of treated papers. However, it is also known that zine oxide is a photosensitizer (56) which may trigger photo-oxidation of treated papers to initiate a chemical chain reaction that will lead eventually to the formation of acidic products (57). Moreover, the interaction of zinc oxide and zinc carbonate with copper, iron and cobalt present in the paper and their subsequent effects on paper stability have not been studied. 

A geological survey of India recently discovered three major deposits at Nallakonda, the lead-copper belt in Andhra Pradesh. The total reserves of all three are about 60.7 million tons. The interesting part of the investigation was that the samples indicated the presence of significant amounts of silver, cobalt, arsenic, and nickel, recovery of which was considered economically possible. 

One method used to isolate a X-ray line from unwanted background and noise, employs equilibrated filters. It consists of linking the concentration of interest to the difference between two measurements. The first is obtained by installing a transmission filter between the sample and the detector to isolate the characteristic radiation of the element wanted and the second by fitting an absorption filter which is opaque to this same radiation. This will enable, for example, to quantify the copper from its main spectral line by using two filters, one made of nickel and the other made of cobalt. The fluorescence originating from the filters themselves is a limiting factor in this method, which is reserved for routine measurements. 

Syshbols.—These are conventional abbreviations of the names of the elements, whose purpose it is to introduce simplicity and exactness into descriptions of chemical nctiona They consist of the initial letter of the Latin name of the element, to which is usually added one of the other letters. If there be more than two elements whose names begin with the same letter, the single-letter symbol is reserved for the commonest element Thus, we have nine elements whose names begin with 0 of these the commonest is Carbon, whose symbol is C the others have doubleletter symbols, as Chlorine, Cl Cobalt, Co Copper, Cu (Cuprum), etc. 

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