Tantalum

Tantalum is a chemical element Ta and atomic number 73. A rare, hard, blue-gray, lustrous transition metal tantalum is highly corrosion resistant and occurs naturally in the mineral tantalite (Fe,Mn)Ta2O6 always together with the chemically similar niobium. It is part of the refractory metals group, which are widely used as minor component in alloys.

The chemical inertness of tantalum makes it a valuable substance for laboratory equipment and a substitute for platinum, but its main use today is in tantalum capacitors in electronic equipment.

Tantalum is estimated to make up about 1 ppm or 2 ppm of the earth’s crust weight. There are many species of tantalum minerals which include tantalite, microlite, wodginite, euxenite and polycrase and most are contained in pegmatite ore bodies.

Tantalite is the most important mineral for tantalum extraction. It has the same mineral structure as columbite (Fe,Mn)(Ta,Nb)2O6; when there is more Ta than Nb it is called tantalite and when there is more Nb than Ta is it called columbite (or neobite). The high density of tantalite and other tantalum containing minerals makes the use of gravitational separation the best method.

Tantalum resources are found in every continent and the quantum of known resources is not an indication of actual resources because of the lack of exploration in some countries. In terms of known resources Brazil has the largest followed by Australia and Africa.

Production

The world mine production of tantalum, usually expressed in lbs of contained Ta2O5, went from 2,100,000 lbs in 2008 to 500,000 lbs in 2009 (Mining Journal September 2010) after the global economic crisis pushed three large mines to close down. This was also due to large stocks held by processors which may have been as much as two year’s production, a legacy of the long-term contacts with miners from previous years.

In 2011 some normality is returning to the market and production is expected to increase and reach levels dictated by the following historical global supply scenario:


Following are details of some operating mines as at January 2011:

Volta Grande Mibra (Brazil): The main tantalite ore-body has a resource of 6.32 Mt (Million tonne) grading 375 ppm of Ta2O5 with 92 ppm of Nb2O5 and 283 ppm of Sn. Currently the plant has a capacity to process 600,000 tpa to produce 300,000 lbs of Ta2O5 concentrate annually (approx. 60% recovery). An expansion to 510,000 lbs of Ta2O5 concentrate annually is planned for late 2011.

Kenticha (Ethiopia): This is a pegmatite sheet of thickness 40-100 metres exposed over 2 km and mined open cut. Annual production is approx.270,000 lbs of contained Ta2O5 concentrate grading 50-70%. 

Marropino (Mozambique): This tantalite ore body has a resource of 11.02 Mt grading 234 ppm of Ta2O5. Production restarted in April 2010 and the Company reported in September 2010 that output has reached 300,000 lbs of contained Ta2O5s. Full production of 500,000 lbs of Ta2O5 per annum is expected by Q2 2011. Inferred resources have also been discovered at Mutala totalling 10.30 Mt grading 236 ppm of Ta2O5 and at Morrua totalling 7.77 Mt grading 463 ppm of Ta2O5.



Pitinga (Brazil): The Pitinga mine in central Amazon produces primarily a tin (cassiterite) concentrate as well as a niobium/tantalum (columbite/tantalite) concentrate. The 2008 production of Ta2O5 equivalent was approx. 200,000 lbs per annum.

Yichun (China): The 2008 production output was 120,000 lbs of Ta2O5 concentrate annually.

Additional quantities of Ta2O5 are also being produced in Brazil, the DRC, Nigeria and Rwanda, mostly from the mining of small alluvial and soft-rock deposits by artisinal miners. 

Uses

Capacitors and wire: 
About half the tantalum consumed each year is used within the electronics industry, mainly as powder and wire for capacitors. As the market moves to greater miniaturization, the tantalum capacitor is favored in space-sensitive, high-end applications in telecommunications, data storage and implantable medical devices.



Alloy additives: Alloy additives are the second largest use for tantalum. The metal's high melt point and resistance to corrosion makes it suitable for alloying applications.  Tantalum is used in nickel based superalloys where the principal applications are aircraft engine blades in the aerospace industry and land based gas turbines

.

Mill Products:
 Tantalum's high resistance to corrosion makes the metal ideal for liners in vessels, piping, valves and heat exchangers in the chemical and pharmaceutical industries

Sputtering targets: Sputtering is a physical vapour deposition process for applying thin films to a substrate. A sputtering target is the source of the deposition material. Sputtering targets are used in a variety of applications, including magnetic storage media, inkjet printer heads, logic circuitry and flat panel displays.



Other: Tantalum is used in a range of other applications requiring high corrosive resistance and high temperature strength including surgical implants, cemented carbides and tantalum compounds for optical applications and sonic acoustic wave filters.

Market and Growth

The world demand for Ta2O5 in 2009 was approximately 4,280,000 lbs down from 6,450,000 lbs in 2008. This was made up as follows:

- Capacitor Powder: 40%

- Superalloys: 15%

- Wire: 10%

- Tantalum carbide (TaC): 10%
- Sputtering Targets: 10%
- Mill products: 8%
- Ta compounds: 7%

The actual demand for 2010 is not known but indications are that it was significantly higher than 2009 in view of electronic component demand estimated to have risen approx. 30%. According to Paumanok Publications Inc. in the period 2010 to 2015 inclusive the demand for tantalum is forecast to grow at an accelerated rate of 9.2% as the market rebounds from the significant downturn in 2009.

They forecast that global demand for Ta2O5 equivalent in 2015 will be approx. 7,300,000 lbs with a rather large one year leap in 2013. Historically primary concentrates account for 60% of the Ta2O5 equivalent demand.

However with the accelerated demand and likely shortfall from other sources the likely demand in 2015 for Ta2O5 primary concentrate will be in excess of 4,400,000 lbs annually, which is more than double the 2008 production output.