China Suspends Sulfuric Acid Exports, Global Copper and Fertilizer Supply Under Strain

Market reports indicate that China has announced a comprehensive restriction on exports of by-product sulfuric acid starting May 1, 2026. Only limited special categories such as electronic-grade sulfuric acid will be exempt. Prior to this, exports had already been reduced through quota controls to around 700,000 tons, a significant decline from the same period last year, widely seen as a signal of tightening export policy.

Once the news emerged, the global sulfuric acid market tightened sharply. Mining and agricultural economies heavily dependent on Chinese sulfuric acid—including Chile, India, the Democratic Republic of the Congo, Zambia, and Morocco—felt immediate pressure. Sulfuric acid prices in Chile had already risen by 44% before the formal restriction, with further upward pressure continuing to build.

As the world’s largest producer of sulfuric acid, China’s withdrawal comes at an especially critical time. The effective closure of the Strait of Hormuz has already disrupted global sulfur supply.

Following an escalation of conflict in the Middle East at the end of February 2026, the Strait of Hormuz was effectively blocked. The region accounts for roughly one-third of global sulfur production, and about 50% of seaborne sulfur passes through the Gulf. As sulfur is the key raw material for sulfuric acid, supply disruptions have triggered a sharp price surge. Over the past month, sulfuric acid prices in both China and international markets have risen by more than 50%, while sulfur prices have increased by over 40%.

The export restriction beginning May 1 implies that approximately 4.6 million tons of annual sulfuric acid supply will be removed from global markets. The shortfall is unlikely to be fully offset. Japan and South Korea may collectively increase exports by about 500,000 tons, but the actual global deficit is expected to reach approximately 2.8 million tons.

Copper Mining Costs Reshaped by Sulfuric Acid Constraints

Globally, around 20% of copper production relies on hydrometallurgical (heap leaching) processes, which require large volumes of sulfuric acid to extract copper from oxide ores.

Chile, the world’s largest copper producer, imports more than 1 million tons of sulfuric acid annually from China, with roughly one-fifth of its copper output dependent on sulfuric acid processing. Copper belts in Africa, including the DRC and Zambia, are also highly reliant on Chinese sulfuric acid. In the DRC, nearly 80% of sulfur supply originates from Middle Eastern sulfur conversion. The combined impact of Middle East disruptions and China’s export restrictions is creating a dual shock.

Copper treatment charges (TC/RC) have fallen to an extreme historic low of -$78 per dry metric ton, signaling severe stress in smelting economics. Analysts warn that sulfur and sulfuric acid shortages could significantly constrain copper mining output.

Agricultural Pricing System Rewritten by Raw Materials

Another major use of sulfuric acid is in phosphate fertilizer production, accounting for approximately 54% of global sulfuric acid demand. Amid increasing volatility in global fertilizer markets, China has already deployed national fertilizer reserves domestically, and phosphate fertilizer producers have temporarily stabilized end-user prices under price control policies. The reference price for 45% sulfur-based compound fertilizer remains at 3,350–3,650 RMB per ton.

However, no such buffer exists in global markets. Sulfuric acid shortages are directly increasing phosphate fertilizer production costs. India, a major fertilizer consumption hub, is facing severe supply constraints due to China’s export restrictions. Combined with sulfuric acid prices doubling this year, procurement difficulty and input costs have risen sharply for producers.

Sulfuric acid is a foundational input in producing key fertilizers such as diammonium phosphate (DAP), and shortages are already threatening Indian fertilizer manufacturers. Cost pressures are also eroding profit margins across the sector.

The previously stable global model of “Middle East sulfur → China processing → global consumption” has been disrupted. Two critical supply chains have fractured simultaneously: Middle Eastern conflict has cut off upstream sulfur supply, while China’s export restrictions have constrained downstream sulfuric acid availability.

As a result, overseas fertilizer and copper smelting industries are forced to seek alternative sources, absorb higher costs, or increase domestic self-sufficiency. The foundational supply lines of global industry and agriculture are increasingly concentrated in a few critical nodes, and real-world price spikes and production slowdowns are already materializing.