Custom Search

Sodium cyanide

horizontal rule

horizontal rule

Sodium cyanide is an important chemical that has been manufactured in Australia since the late 1980s. There are now three plants.

Sodium cyanide is also known as cyanide of sodium, cymag, hydrocyanic acid sodium salt. It is a white powder or solution in water. Liquid cyanide contains 30 per cent cyanide while the solid is 98 per cent pure in Australia (though lower grades are produced overseas).

Sodium cyanide (NaCN) is a chemical used overseas predominantly in metal plating and chemical applications such as dyes and pharmaceuticals. In Australia it is principally used for the gold mining industry to extract gold from gold bearing ore using the carbon-in-leach and carbon-in-pulp processes with 98 per cent of Australia’s gold production dependent on it. These processes enable commercial recovery of gold at very low concentrations (down to just 0.85gm per tonne or 0.85 ppm of soil or mine tailings). Between 300 and 500 tonnes of sodium cyanide (valued at ca. US$0.7m) is required for each tonne of gold (valued at say $13m) produced so that cyanide represents around 8 per cent of the value of gold produced.

Sodium cyanide is also used in nickel production as an arsenic suppressant. Notes
bulletAbout 90 per cent of Australia’s gold reserves are non-alluvial providing 98 per cent of production. Less than 1 per cent of Australia’s gold production does not use sodium cyanide.
bulletAcid thiourea has been used as an alternative to sodium cyanide but this is unsuitable for use in soils with soluble iron and clays as typical of Australia.
bulletSodium cyanide extraction has replaced the mercury amalgam process which is environmentally harmful and less than two-thirds as efficient.
A small amount of sodium cyanide is also used in electroplating and metal cleaning baths, metal hardening and insecticides.

Manufacture

Sodium cyanide is manufactured by the Andrussow process using ammonia, air, natural gas and caustic soda. The process reacts ammonia with natural gas and air over a platinum/rhodium catalyst to produce hydrogen cyanide gas. Typically the production of one tonne of sodium cyanide requires:
bulletnatural gas - 36 gigajoules (940m3)
bulletcaustic soda - 0.95 tonnes
bulletammonia - 0.65 tonnes
bulletelectricity - 0.67 MW
 

Ticor is believed to be using technology less demanding of ammonia.

Production at all three production centres is at around world scale using the latest technology having been established in the last ten years.

Australian Gold Reagents (AGR)

AGR on the web

AGR is jointly owned by Wesfarmers CSBP (75%) and Coogee Chemicals (25%).

A view of the AGR sodium cyanide plant
AGR's sodium cyanide plant

Australian Gold Reagents (AGR) manufactures sodium cyanide in liquid and dry form at Kwinana in Western Australia with a production capacity of about 65 000 tonnes of sodium cyanide (on a dry weight basis). Sodium cyanide is supplied in liquid solution (30 per cent solid) and more recently now in solid. The raw material ammonia is supplied by Wesfarmers and caustic soda by Nufarm-Coogee. Though  more than twice the bulk of the dry form and hence more expensive to distribute, it is generally more competitive by avoiding additional equipment and drying costs. Liquid cyanide was considered by the West Australian Environmental Protection Authority to be more hazardous to transport and until 1996 in Western Australia it was required to be moved by rail. Without railway access, some locations were for a time compelled to use the imported dry form of cyanide.  

In 1998 a A$30m expansion doubled production to 70 000 tonnes per year by plant duplication. 

In September 2001, the EPA approved production of 25 000 tpa of the solid form.

Prior to the AGR expansion, Orica indicated an interest to establish a 30 000 tpa plant at Kalgoorlie (Mungari Industrial Park) (Kalgoorlie Miner, 28 Sept. 1996 but shelved in February 1998 [together with a xanthate plant]. It involved a $25m ammonia import terminal in Esperance.). Given such a plant would require around 1 petajoule of gas provided by the new Goldfields gas line, it would (by ACTED calculations) incur a pipeline overhead charge penalty of around $70 per tonne of cyanide compared with its competitor AGR at Kwinana. The freight saving of regional manufacture would be further offset by having to freight the caustic soda and ammonia to Kalgoorlie at around $100 per tonne each (say $160 per tonne of cyanide produced).

  Reflecting international scales of production and technology, quality is equal to imports with prices at import parity. Liquid cyanide, though cheaper to produce than solid sodium cyanide that advantage is offset by higher transport costs, and is generally priced by AGR to be competitive with the dry (ie. imported) form on an into store basis. Cyanide prices in Western Australia during 1995 ranged from $1 300 per tonne to $2 800 tonne depending on form, size of packs and size of orders. Liquid cyanide prices tend to be about $100 to $200 per tonne cheaper than dry cyanide (ex factory dry weight basis). Offsetting that advantage is the additional cost of freight and specialist equipment required to receive and dispense. However, the additional transport cost has its limits so that dry form is more economic if freighted more than about 1 000 kilometres inland. Accordingly, the rail head near the gold producing area around Kalgoorlie is dominated by liquid cyanide produced by AGR while more distant locations tend to use cyanide from Australia's other two producers, ICI and Ticor in Queensland (and some imports from overseas suppliers such as Degussa). In other words, AGR can readily set the ex factory price to maximise income and market share currently supplying about one-half the West Australian market.

It was fortunate for AGR that its competition chose to establish in Queensland - a decision that now provides a substantial local market advantage. AGR can now expand its market with liquid (or dry) cyanide. Although its raw materials and energy requirements are at or above international prices, but with no other source of competitive advantage, domestic and international transport cost savings provide a substantial advantage.

Ticor Chemical Company

This operation was closed in April 2004 and the site sold in July 2004.

Ticor Chemical Company is located at Yarwun near Gladstone, Queensland. the plant was commissioned in 1991 and in 1994 DuPont acquired a 50 per cent interest. Like its nearby located competitor ICI, it generally produces the dry form of sodium cyanide with a production capacity of about 40 000 tonnes tpa and is now 100% owned by Ticor. The company employs about 75 persons. The required raw materials are purchased on the open market.

Production of briquettes are 15gms, 31mm by 30mm by 11mm with a specific gravity of 1.6 and a minimum of 98 per cent purity (0.2% water maximum). The cyanide is packaged in 1 000 kg Intermediate Bulk Containers of plywood.

Orica

Orica operates a plant at Yarwun (close to the Ticor operation) with a production capacity of about 35 000 tpa of dry cyanide. Ammonia is road freighted and shipped.

 

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/