Custom Search

 

Zirconia, zirconium chemicals and zirconium metal


horizontal rule

 

Zircon is the zircon silicate mineral (ZrSiO4) found with titanium minerals notably ilmenite. Zircon is also found naturally as baddeleyite notably in South Africa. It is separated by a wet-gravity technique followed by a dry-separation magnetic and electrostatic process. Some 40 per cent of zirconia production comes from the cracking of zircon which is very stable and requires extensive energy and/or chemical processing. Some is produced as a by-product from the Palabora copper mine in South Africa.

It is principally used as an opacifier in ceramic glazes, refractories, electron absorber in nuclear reactors, armour plating on military aircraft, heat shield in space shuttles and potentially as solid oxide fuel cells in hydrogen powered vehicles.

World production of zircon was 900 000 tonnes in 1998 of which 385 000 tonnes was produced in Australia (300 000 from Western Australia). Australian production which was 530 000 tonnes in 1989, is projected to be 360 000 tonnes in 2000. Eneabba, in WA supplies 145 000 tonnes per year.  

New deposit

At Peak Hill, near Dubbo New South Wales, Alkane Exploration, owns a deposit of 50 million tonnes providing a 250 year life at 200 000 tonnes per year. This would produce 3500 tonnes of zirconia (8 per cent of world output of 52 000 tonnes) and 25 tonnes of yttria (10 per cent of world production). This deposit is particularly attractive as it not only has yttrium (used in CRT tubes), it is in a mineral form that can be cheaply extracted with sulphuric acid. This acid could be provided by the development of the gold containing sulfide zone, which by roasting, would provide the required sulfuric acid. The feasibility study will be completed by end of 1999.

Zirconia prices averaged between US$4 and US$7 per kilogram. 

Alkane Exploration NL is getting encouraging results from test work at its Toongi, NSW (near Dubbo) prospect, and is positioning itself to produce 3500 tonne zirconia/hafnia concentrate, 1600 t yttria/REO concentrate and 875 t tantalum/niobium concentrate; the company is looking for a jv partner with marketing knowledge and development capital. Project viability depends partly whether the company can produce by-product sulphuric acid from its Peak Hill sulphide gold orebody.

Western Australia

Western Australia produces around 300 000 tonnes p.a. of zirconia representing one-third of world production. It is produced by four titanium minerals producers of which over half is produced by RGC Mineral Sands. BHP Titanium Minerals is anticipated to produce 20 000tpa from the Beenup mine.

Zirconia (ZrO2) is manufactured in Western Australia by AFM and by Millennium Performance Chemicals (MPC - formerly Hanwha Advanced Ceramics).

AFM produces zirconia from naturally occurring zircon with an energy-intensive high temperature disassociation technique to produce zirconia with silica fume (SiO2) as by-product. It can also be produced in plasma furnaces.

Other techniques for the production of zirconia includes by its:
bulletextraction using caustic soda (or at higher temperatures with soda ash) to produce hydrated zirconia.
bulletreaction with chlorine (in the presence of carbon ZrSiO4 + C + 4Cl2 > ZrCl4 + SiCl4 + 4CO) to produce zirconium tetrachloride (ZrCl4) and silicon tetrachloride which can be separated with the very different condensation temperatures. As with the production of its cousin, titanium dioxide, the tetrachloride is hydrolysed to zirconium oxychloride (as imported by Hanwha) and then calcined or precipitated with the addition of alkali.
A high purity form is produced by MPC  from imported zirconium oxychloride (principally China). The zirconia produced by AFM is too tough for chemical processing by MPC and more recently have introduced their own mill.

Iluka Resources will build (2001) a $20 million zircon finishing plant at the company's Western Australian mineral processing complex. The plant will remove impurities to allow the mineral to be graded into specialised products for ceramic glazes, refractory linings and chemical processing.

Zirconium chemicals

ICI Australia (now Orica) established the ICI Technology plant (trading as Z-Tech) at Rockingham adjoining Kwinana, south of Perth in 1988 to produce about 450 tonnes per year of high purity (up to 99.95 per cent) zirconia, and about 450 tonnes of zirconia chemicals from impure zirconia. ICI's research facilities for advanced materials were in Melbourne, Victoria and now Carpenter Advanced Ceramics; and the zirconia is imported from Florida USA. The main raw materials (other than zirconia) are sulfuric acid and ammonia produced from the nearby Wesfarmers CSBP plant. Its competitive advantage was clearly then not substantial. The Z-Tech plant ceased operation in 1992.

 

Hanwha's zirconium chemicals plant

In 1994 the plant was purchased byHanwha of Korea and was known as Hanwha Advanced Ceramics Australia Pty Ltd. In recommencing operations, the former Z-Tech plant could purchase its requirements of zirconia locally, representing about 10 per cent of AFM's turnover and sells some of the sulfate to the nearbyTiwest plant. 

In February 2000 the plant was acquired by Millennium Inorganic Chemicals and is now known as Millennium Performance Chemicals supplying chemicals including for MIC's competitor, Tiwest. In 2004 it was acquired by Doral that also has an interest in the AFM plant.

Though zirconia and its products are high value products, $2 000 to $4 000 per tonne, transport costs, quality and short term supply help competitiveness. The zirconium sulfate is supplied to the nearby Tiwest pigment plant as dilute but cheap 12 per cent solution, whereas competing imports, to minimise transport costs have had to be converted to a 30 per cent paste. Convenience of local supply will help sales against imports and provide a secure market for about one-third of the plant's turnover.

The company produces some 20 000 tonnes of zircon flour (including milled silica, garnet and aluminas).

The key products are
bulletHigh purity monoclinic zirconia. It consists of 99.95 Wt% of ZrO2 (450 tonne capacity). It is used for ceramics.
bulletYttria partially stabilised zirconia containing 5.2wt % of Yttria
bulletZirconium hydrate as a moist cake used for UV protection in the paint in the paint industry.
bulletZirconium carbonate (160 tonne capacity) and zirconium sulfate (700 tonne capacity).

Outlook

Established in isolation to primarily produce ceramic powders, the former Z-Tech plant is now in a more favourable environment, not only as a supplier of ceramic grade powder, but especially for zirconium chemicals. These could include zirconium carbonates, hydrous zirconia and linkages with silicon based ceramics (silicon carbide or silicon nitride), or with alumina ceramics (zircon toughened aluminas).

The Australian market is about 300 tonnes per year of zirconium chemicals broadly split between zirconium sulfates and zirconium carbonates - i.e.. approximately the capacity of the zirconium chemicals plant. World-wide, some 5 000 tpa of zirconium chemicals (expressed as zirconia ZrO2) are used as inert fillers in paints and for leather tanning (to replace the traditional but hazardous chromium sulfates) besides its primary use in high grade specialty ceramics.

With Western Australia as a major producer of zirconia (30 per cent of world production at 400 000 tonnes per year), this industry, which developed using locally developed technology (ICI and the CSIRO), could therefore become an important exporter.

One strategy may be for AFM to diversify into ceramics with the company confined to zirconium chemicals. A less optimal strategy would be for AFM to expand into low purity ceramics (that requires magnesia in which Doral as a former partner of AFM, has an interest). The MPC plant would then focus on higher purity ceramics, perhaps with some production of chemicals. The ability to enter Asian markets, which contributed to the failure of the plant under ICI's ownership, may now be overcome with new ownership.

Since 1991, the Tiwest titanium dioxide pigment plant established in 1991, uses zirconium sulfate to modify the UV resistance of materials in which its pigment is used.

MPC imports its raw materials though Western Australia is large exporter of zircon.
AFM across the road produces zirconia and along the road, titanium dioxide pigment is produced by chlorination (though after the Becher process to remove the iron oxide component of ilmenite.

The major source of raw material for MPC is the imported oxychloride produced in a country that:
bulletproduced zirconium metal as a strategic material (ie. government directed)
bulletproduced with lenient environmental restraints
bulletlower chlorine costs than in Australia (the silicon tetrachloride is hydrolysed to hydrochloric acid.
The company is evaluating a 5000 tonne oxychloride plant.

Contact details

Postal

PO Box 283
Rockingham
Western Australia 6168

Actual

1 Ward Road
Rockingham
WA 6168

Telephone: 61 9 419 4000
Fax :61 9 439 1055

Products

High purity zirconia (99.5%+ zirconia) for structural and electronic uses, zircon flour, zirconium sulfate solution and ammonium zirconium carbonate solution.

 

horizontal rule

Fused Zirconia

A fused zirconia (ZrO2) plant is operated byAustralian Fused Materials at Rockingham, adjoining Kwinana, some 40 km south of Perth Western Australia since 1994. The company also produces fused alumina.

Key producers are South Africa 10 000 tpa but projected to halve with move to underground mining, and Russia. Both countries use baddeleyite a natural form of zirconia. 

Production removes silica from zircon. It involves reacting zircon with coke in an electric arc furnace at temperatures of around 3 000C. On rapid cooling a granular material is produced which is screened and or further crushed.

Australian Fused Materials, is owned by Japan Abrasive Company (JACO), ACAP (Alcoa of Australia) and by Doral Minerals (owned by Iwatani International Corporation) which was established in 1991. Doral since 2004 also owns the zirconium chemicals plant.

It produces about 4 000 tonnes of fused zirconia representing about 10 per cent of world production of 40 000 tonnes.

About 2000 tonnes of silica fume is coproduced. A second furnace is under consideration to cost A$11 million. 

In May 1998 the courts upheld an appeal by JACO that a $14 million expansion proposed by the other two partners that would have lifted production to 8 000 tonnes per year (so as to be the largest in the world), was not in the interest of the company.

Zirconia is used as a refractory liner and feed for manufacturing advanced ceramics.

Australian Fused Materials
Australian Fused Materials
bulletComment

RGC at Eneabba supplies the feedstock zircon (zirconium silicate). After processing in an electric arc furnace with coke, the resultant silica is collected as silica fume (around 1500 tpa) and the fused zirconia (zirconium dioxide) is granulated, screened and bagged for export.

A relationship with Asahi Glass Company of Japan provides some of the technology and a market in ceramics.

AFM also produces fused alumina. Total value of production in 1999 was A$28 million of fused alumina, fused zirconia and fumed silica of which 90 per cent is exported - mainly to China and Taiwan. 

Australian Fused Materials
PO Box 84 Rockingham
WA 6168
Tel +618 9439 2236
Fax +618 9439 2892

horizontal rule

Zirconium metal

Zirconium metal has a world market of 5 000 tonnes and is largely used in the nuclear industry (about 90 per cent) and in the chemical industry and in high density battery manufacture.

Manufacture is via zirconium chloride (produced directly from zircon sand, carbon and chlorine) and its reduction with magnesium metal to a sponge.
The sponge is converted to the ingot in an electric arc furnace. The process is energy-intensive with energy accounting for over one-quarter of the market value of the metal.

This report is NOT indicative of our private client reports.

It has been prepared simply to get you started. It is cheaper than you will find on the web for other detailed information and thus we rarely recover the cost of its preparation.

Given the value of your time, if only a small percentage of the information proves useful, then it should have paid for itself. Feel free to discuss the preparation of a confidential custom report.

Chemlink Pty Ltd ACN 007 034 022. Publications 1997. All contents Copyright © 1997. All rights reserved. Information in this document is subject to change without notice. Products and companies referred to are trademarks or registered trademarks of their respective companies or mark holders. URL: www.chemlink.com.au/