China quietly turns off supply of world's most used industrial chemical

LoomTex is a textile manufacturer based in Geelong, Victoria. (Supplied: LoomTex) Link copiedShareShare articleChina has moved to protect its supply of the world's most used industrial chemical, with ramifications for everything from food production to fashion and mobile phones. Sulphuric acid is a crucial ingredient in the manufacture of batteries, clothing and phosphate fertilisers, and is also used to treat drinking water, purify petroleum, and produce some metals and computer chips. China is a key exporter, but it relies on imported sulphur — itself a by-product of oil refining and smelting — to make it. In 2025, about half of the global sulphur supply came from the Middle East. With trade disrupted, Beijing has banned exports of sulphuric acid to shore up its domestic supply. It means Australian manufacturers are facing a difficult choice: either stock up on the highly corrosive and combustible chemical or go without their key ingredient. In Geelong in south-western Victoria, textile manufacturer LoomTex is trying to keep its heritage of weaving, dying and milling alive through sustainable fabrics. Chief executive Samantha Van Zyl said sulphuric acid was one of several chemicals relied on in research and development. Samantha Van Zyl says sulphuric acid is a necessary ingredient in making textiles. (Supplied: Loomtex) "It's critical as an auxiliary step in the lab … for fibre innovation," she said. The supply disruption puts the company in a difficult position. Ms Van Zyl said they were left with the choice to either order more sulphuric acid than normal, which puts them above the threshold for storing dangerous goods, or not have enough supply. "We'd have to bring in WorkSafe Victoria; the fire hazards and safety risks on site as a chemical risk profile completely change. "It's not something that can be done overnight." Samantha Van Zyl says LoomTex is struggling to source three types of acid, including sulphuric. (Supplied: Kate Ballis) Ms Van Zyl said that without the acids, production would suffer, and she could lose customers to overseas manufacturers. "That's a vulnerability and a risk I don't think that we would look to take at this point in time," she said. LoomTex relies on multiple types of acid in its production process. (Supplied: Stu Ross/Milk Video) Sulphuric acid is made in two ways: either by using sulphur or as a by-product of metal smelting. Head of sulphur and sulphuric acid research at Argus Consulting Services, Meena Chauhan, said the acid was produced worldwide, but China was the lead exporter. "Last year, they exported close to 5 million tonnes for the first time," she said. China relies on importing sulphur, a by-product from oil refining and gas processing, to make sulphuric acid. In 2025, about 73 million tonnes of sulphur were produced globally. "We estimated that Middle Eastern trade represented about 50 per cent of global trade flows," Ms Chauhan said. The Middle East represents more than half of the global sulphur trade. (Reuters) She said the effect of the Iran war on supply was twofold: the closed Strait of Hormuz stopped vessels carrying it, and damage was caused to refineries and processors in the region that produced it. She said China's ban on exporting sulphuric acid, which came into effect on May 1, was an attempt to protect their "downstream industries" from disruption. Attention is turning to other sulphur-exporting countries like Canada for an alternative supply, but Ms Chauhan said there were issues with logistics and volume. Australia produces some sulphuric acid for its domestic market from metal smelting in Queensland, but not at the grade Ms Van Zyl's textile lab requires. But local supplies may help the leading end user of both sulphur and sulphuric acid — the fertiliser industry. North West Phosphate mines phosphate rock and concentrate in Queensland, which is used by fertiliser manufacturers throughout South-East Asia. Chairman John Cotter said sulphuric acid was a critical element for his customers. John Cotter says changes in the fertiliser trade might affect his business. (ABC North West Qld: Emily Dobson) "Most of those producers use sulphur mixed with water to create sulphuric acid mixed in with phosphate rock," he said. "That gives you the basic ingredients for all of the fertiliser blends that you find in the shops." So far, his business had not been impacted, but Mr Cotter expected it to happen soon. "These are the sort of structural changes in the trading market of commodities globally that we're seeing as a result of the conflict." Ms Chauhan said Mr Cotter's fears were warranted. Sulphuric acid did not become the world's most widely used industrial chemical based on its versatility alone. As the by-product of a by-product, historically, it has also been pretty cheap. But with demand for both chemicals also coming from the metal industry, which can absorb higher prices, Ms Chauhan said fertiliser product

China quietly turns off supply of world's most used industrial chemical

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