Virtually all sulphur produced worldwide is used to make sulphuric acid, mostly produced by the Contact Process. In this process sulphur is burned in air, or ores like pyrite are heated in air, to produce sulphur dioxide. This is then converted to sulphur trioxide by heating in air to about 4500C in the presence of a V2O5 catalyst. The sulphur trioxide is then dissolved in concentrated sulphuric acid and then reacted with water.

Sulphur on aragonite, Cianciana sulphur mine, Sicily

The world’s largest producers of sulphur in 2020 were China, US, Russia, Canada and Saudi Arabia. In total the world produced 78Mt, down on 2019 due to Covid restrictions. Total recoverable world resources from all sources are estimated to be about 5 billion tonnes. There is almost unlimited amounts of sulphur in gypsum, anhydrite, coal and oil shales but would require the development of low cost methods of extraction to be of value.

Sulphuric acid (H2O5) is primarily used in the fertiliser industry, particularly superphosphate, ammonium phosphate and ammonium sulphate. It is widely used in the manufacture of chemicals such as acids, sulphate salts, dyes , explosives and drugs. Many consider that a nation’s sulphuric acid production is a measure of industrial strength.

In 2020 sulphur sold for USD40/t in the US, down from USD80/t in 2018. On Alibaba sulphuric acid sells for USD100 to USD 300/t, depending upon order size and quality.

Sulphur is currently produced in Australia as a by-product of oil processing and metal processing. Cobalt Blue Ltd (ASX: COB) is planning to produce sulphur along with cobalt from its Broken Hill Cobalt Project. In the past sulphur was produced from pyrite at the Brukunga and Wheal Ellen mines in South Australia.

In summary, there is no meaningful ASX exposure to sulphur. It is generally a very small part of a company’s revenue from mineral or oil processing. COB could be an exception, although it is mainly valued on its cobalt holding.