The city of Jos in Nigeria has always been known as the Tin city way back to 1900. Tin is a chemical element with the symbol Sn (from Latin: stannum) and atomic number 50. It is a post-transition metal in group 14 of the periodic table. It is obtained chiefly from the mineral cassiterite, which contains tin dioxide, SnO2. Tin shows a chemical similarity to both of its neighbors in group 14, germanium and lead, and has two main oxidation states, +2 and the slightly more stable +4. Tin is the 49th most abundant element on earth and has 10 stable isotopes, the largest number of stable isotopes in the periodic table, thanks to its magic number of protons.
Tin ore {Cassiterite} is the second –easiest ore to mine. It is mined from tin veins. Cassiterite is a tin oxide mineral, SnO2. It is generally opaque but it is translucent in thin crystals. Its luster and multiple crystal faces produce a desirable gem. Cassiterite has been the chief tin ore throughout ancient history and remains the most important source of tin today.
Tin ore is employed in plating, production of tin oxide used in paint, paper and ink industries, production of tin oxide resistors and electric lead wires.
OCCURANCE
Tin is generated via the long s-process in low-to-medium mass stars (with masses of 0.6 to 10 times that of Sun), and finally by beta decay of the heavy isotopes of indium.
Tin is the 49th most abundant element in Earth‘s crust, representing 2 ppm compared with 75 ppm for zinc, 50 ppm for copper, and 14 ppm for lead.
Tin does not occur as the native element but must be extracted from various ores. Cassiterite (SnO2) is the only commercially important source of tin, although small quantities of tin are recovered from complex sulfides such as stannite, cylindrite, franckeite, canfieldite, and teallite. Minerals with tin are almost always associated with granite rock, usually at a level of 1% tin oxide content.
Because of the higher specific gravity of tin dioxide, about 80% of mined tin is from secondary deposits found downstream from the primary lodes. Tin is often recovered from granules washed downstream in the past and deposited in valleys or the sea. The most economical ways of mining tin are by dredging, hydraulicking, or open pits. Most of the world’s tin is produced from placer deposits, which can contain as little as 0.015% tin.
TIN REFINING
Tin is extracted by roasting the mineral casseterite with carbon in a furnace to approximately 2500 degrees Fahrenheit. The next step involves leaching with acid or water solutions to remove impurities. Electrostatic or magnetic separation helps to remove any heavy metal impurities
APPLICATION
About half of all tin produced is used in solder. The rest was divided between tin plating, tin chemicals, brass and bronze alloys, and niche uses.
Solder
Tin has long been used in alloys with lead as solder, in amounts 5 to 70% w/w. Tin with lead forms a eutectic mixture at the weight proportion of 61.9% tin and 38.1% lead (the atomic proportion: 73.9% tin and 26.1% lead), with melting temperature of 183°C (361.4°F) . Such solders are primarily used for joining pipes or electric circuits. Since the European Union Waste Electrical and Electronic Equipment Directive (WEEE Directive) and Restriction of Hazardous Substances Directive came into effect on 1 July 2006, the lead content in such alloys has decreased. Replacing lead has many problems, including a higher melting point, and the formation of tin whiskers causing electrical problems. Tin pestcan occur in lead-free solders, leading to loss of the soldered joint. Replacement alloys are rapidly being found, although problems of joint integrity remain.
Tin plating
Tin bonds readily to iron and is used for coating lead, zinc and steel to prevent corrosion. Tin-plated steel containers are widely used for food preservation, and this forms a large part of the market for metallic tin. Copper cooking vessels such as saucepans and frying pans are frequently lined with a thin plating of tin, since the combination of acid foods with copper can be toxic.
Specialized alloys
Tin in combination with other elements forms a wide variety of useful alloys. Tin is most commonly alloyed with copper. Pewter is 85–99% tin bearing metal has a high percentage of tin as well.Bronze is mostly copper (12% tin), while addition of phosphorus gives phosphor bronze. Bell metal is also a copper-tin alloy, containing 22% tin.
The niobium-tin compound Nb3Sn is commercially used in coils of superconducting magnets for its high critical temperature (18 K) and critical magnetic field (25 T). A superconducting magnet weighing as little as two kilograms is capable of the magnetic field of a conventional electromagnet weighing tons
A small percentage of tin is added to zirconium alloys for the cladding of nuclear fuel.
Most metal pipes in a pipe organ are of a tin/lead alloy, with 50/50 being the most common composition. The proportion of tin in the pipe defines the pipe’s tone, since tin has a desirable tonal resonance. When a tin/lead alloy cools, the lead cools slightly faster and produces a mottled or spotted effect. This metal alloy is referred to as spotted metal. Major advantages of using tin for pipes include its appearance, its workability, and resistance to corrosion
Optoelectronics
The oxides of indium and tin are electrically conductive and transparent, and are used to make transparent electrically conducting films with applications in Optoelectronics devices such as liquid crystal displays.
Other uses
Tin (II) fluoride is added to some dental care products as stannous fluoride (SnF2). Tin (II) fluoride can be mixed with calcium abrasives while the more common sodium fluoride gradually becomes biologically inactive in the presence of calcium compounds. It has also been shown to be more effective than sodium fluoride in controlling gingivitis
Organotin compounds
Of all the chemical compounds of tin, the organotin compounds are most heavily used. Worldwide industrial production probably exceeds 50,000 tonnes. PVC stabilizers The major commercial application of organotin compounds is in the stabilization of PVC plastics. In the absence of such stabilizers, PVC would otherwise rapidly degrade under heat, light, and atmospheric oxygen, resulting in discolored, brittle products. Tin scavenges labile chloride ions (Cl−), which would otherwise initiate loss of HCl from the plastic material. Typical tin compounds are carboxylic acid derivatives of dibutyltin dichloride, such as the dilaurate.
Biocides
Some organotin compounds are relatively toxic, with both advantages and problems. They are used for biocidal properties as fungicides, pesticides, algaecides, wood preservatives, and antifouling agents. Tributyltin oxide is used as a wood preservative.
Organic chemistry
Some tin reagents are useful in organic chemistry. In the largest application, stannous chloride is a common reducing agent for the conversion of nitro and oxime groups to amines. The Stille reaction couples organotin compounds with organic halides or pseudohalides.
MARKET
Export of crude Tin ore is good business but refining to obtain pure TIN ready to be used is better although it requires enormous investment so also is the return on investment. World consumption of refined TIN was 378,000 metric tons in 2017. The leading refined TIN consuming countries are China, the United States, Japan and Germany. Demand for Tin worldwide is expected to grow largely because of increased consumption in China, which is being driven by growth in the electronics, Li-ion batteries and other related products
REQUIREMENT AND CONDITIONS FOR MINING LEAD IN NIGERIA
There are two options available to a company or an individual to enter into the mining industry in Nigeria.
Through the acquisition of an existing mining Lease from the original owner, approval must be obtained from the Ministry of Solid Minerals Development for such a purchase.
Fresh mining lease
Procedure for Mineral Title Licences/Leases and Permits:
- Duly completed application form
- Coordinates of the area of application
- Certificate of incorporation
- Attestation
- Letter of consent from landowner(s)/occupier(s)
- Types of minerals
- Work programme/pre-feasibility report
- Evidence of payment
- Technical capability
- Financial capability
In order to encourage investment in the solid minerals industry in Nigeria, Government is offering the following incentives
- 3-5 years Tax Holiday
- Deferred royalty payments
- Possible capitalization of expenditure on exploration and surveys
- Extension of infrastructure such as roads and electricity to mining sites, and provision of 100% foreign ownership of mining concerns.
The mining industry in Nigeria is regulated by the Nigerian Minerals and Mining Act of 2007, National Minerals and Metals Policy 2008 and Nigerian Minerals and Mining Regulations 2011.
CONCLUSION
Business Advisory Network ‘BAN’ will work with you and assist you to process mining lease from the federal government. We will help you source for a site with rich mineral content. Mining is a technical field although the financial reward is enormous; therefore to succeed you need experts to guide you to avoid fatal mistakes that will erode your capital.
Other things BAN can do for you include but not limited to help you to determine the grade of TIN ore in the site, source market for your mined minerals, both locally and internationally BAN will also help you arrange security at your mining sites. It will interest you to know that export of refined pure TIN is where you make a kill. BAN will help you to set up a refinery for TIN ore in Nigeria. The capital outlay for this is huge but even so much more is the return on investment.