Global Sulfur Supply Disruption Due to Strait of Hormuz Blockade - March 2026

The escalation of the military conflict between the United States, Israel, and Iran on February 28, 2026, has triggered a severe disruption to global sulfur supply chains. Following coordinated airstrikes by the US and Israel on Iranian territory under Operation Epic Fury, which resulted in the death of Iran's Supreme Leader Ali Khamenei, the Islamic Revolutionary Guard Corps (IRGC) declared the Strait of Hormuz closed and issued threats against any vessel attempting to transit the waterway.

The Strait of Hormuz is the most critical maritime chokepoint for global sulfur trade, handling approximately 44% of worldwide seaborne sulfur shipments. Major sulfur export terminals located in the Persian Gulf, including Jubail in Saudi Arabia, Ruwais in the United Arab Emirates, and Imam Khomeini Port in Iran, all depend on the Strait for access to the Indian Ocean and global markets. With commercial transit through the Strait collapsing by an estimated 90%, the global sulfur supply chain has been severely disrupted.

The disruption was compounded by direct physical damage to production facilities in the region. Iranian retaliatory strikes hit Qatar's Ras Laffan Industrial City and Mesaieed Industrial City, prompting QatarEnergy to halt production of LNG, sulfur, urea, methanol, polymers, and aluminum. Ras Laffan alone supplies approximately 10,000 tonnes per day of liquid sulfur for export. Saudi Aramco's Ras Tanura refinery, with a capacity of 102,000 tonnes per year of sulfur, was also shut down after being struck by debris from intercepted Iranian drones. Iran itself banned all food and agricultural product exports to protect domestic supply, further tightening global availability.

The sulfur market was already under significant stress before the conflict. Global sulfur prices had surged more than 100% throughout 2025, driven by constrained supply from Russian refinery damage, rising demand from Chinese lithium iron phosphate battery production, and expanding nickel processing operations in Indonesia. The global sulfur supply gap was estimated at approximately 5.13 million tonnes heading into 2026. The Hormuz closure has dramatically worsened this pre-existing deficit.

China, the world's largest sulfur importer, is particularly exposed. The country imported 9.61 million tonnes of sulfur in 2025, with nearly 40% originating from the UAE, Saudi Arabia, Kuwait, Oman, and Iran. As of late February 2026, Chinese port inventories stood at approximately 1.8 million tonnes, sufficient for only 1.2 to 1.5 months of consumption during the critical spring plowing season. Domestic sulfur prices in China jumped to 4,250 yuan per tonne immediately after the conflict began, a 5% increase in a single day. Asian traders have been scrambling to find alternative supplies, but availability from other regions such as Canada remains limited.

The disruption has severe downstream consequences for the Central African Copperbelt, particularly in the Democratic Republic of the Congo and Zambia. The Copperbelt imports approximately 2 million tonnes of sulfur annually, primarily from the Middle East. This sulfur is converted into roughly 6 million tonnes of sulphuric acid through local sulfur burners, which is essential for leaching copper from oxide ores. More than 90% of sulfur imported into Africa originates from the Middle East and must transit the Strait of Hormuz.

The DRC is the world's second-largest copper producer, with output reaching 3.2 million tonnes in 2025. Copper oxide ore is the dominant source in the DRC, and sulphuric acid is the primary reagent used to extract the metal through heap leaching. Prior to the Hormuz crisis, high-strength sulphuric acid prices in Kolwezi, on the western edge of the DRC Copperbelt, were already trading near all-time highs of $700 to $800 per tonne due to regional export restrictions, elevated copper prices, and an already tight global sulfur market. Zambia had imposed an export ban on sulphuric acid in September 2025, further constraining regional supply.

If the disruption persists beyond approximately three weeks, copper oxide operations in the DRC face the risk of closure as acid stockpiles are depleted. This would directly impact the global copper market at a time when copper prices have already reached record highs, surpassing $6 per pound on COMEX in January 2026. In addition to the 6 million tonnes of acid produced from imported sulfur, regional smelters generate approximately 2.5 million tonnes of sulphuric acid as a byproduct of copper concentrate smelting.

Ivanhoe Mines' Kamoa-Kakula copper complex has been ramping up its on-site smelter near Kolwezi, which is expected to produce up to 700,000 tonnes per year of high-strength sulphuric acid at full capacity. By early March 2026, the smelter had reached approximately 60% of capacity, producing around 1,200 tonnes per day of 98%-pure acid. This local production capacity is of critical strategic importance to the DRC mining sector during the current crisis.

Beyond copper mining, the sulfur supply disruption threatens global agriculture. Sulfur is a primary feedstock for sulphuric acid, which is essential for phosphate fertilizer production. The Middle East accounts for approximately 40% to 50% of traded nitrogen fertilizer volume. The disruption affects 44% of global sulfur trade, 31% of urea trade, 18% of ammonia trade, and 15% of phosphate trade. Urea prices in New Orleans surged by $60 to $80 per tonne in a single trading session. The timing is particularly damaging as Northern Hemisphere farmers prepare for spring planting season.

War-risk insurance cancellations have effectively enforced the blockade beyond physical military threats. Major container shipping companies including Maersk, CMA CGM, MSC, and Hapag-Lloyd have suspended regional operations. Over 150 tankers are stranded outside the Strait, unable to deliver their cargo. Some vessels carrying sulfur remain stuck in the Persian Gulf with no timeline for departure. The crisis represents the first time in modern history that LNG tanker movement through the Strait has dropped to zero.

The situation remains highly volatile and the duration of the disruption is uncertain. If the blockade is resolved quickly, the primary impact will be limited to price spikes and short-term supply adjustments. However, a prolonged closure of several weeks or months would cause sulphuric acid prices to exceed previous records, force copper oxide mining operations to suspend production, significantly increase fertilizer costs worldwide, and ultimately translate into higher food prices with the greatest impact on developing nations in Africa and South Asia.