Chile’s acid crunch threatens global copper supply chains

A shortage of sulfuric acid in [[PRRS_LINK_1]] is exposing a key weakness in the global copper industry: reliance on specialised chemical inputs without which production cannot function.

As the world’s largest copper producer (about 5.5mn tonnes annually), Chile depends heavily on leaching processes, which require substantial volumes of acid to extract copper from oxidised ores. More than half of the country’s refined [[PRRS_LINK_2]] output is tied to this method.

China’s abrupt export shift

The disruption has been triggered by a sharp policy shift in China, where sulfuric acid exports to Chile have fallen to zero after steady flows in previous months. The move reflects Beijing’s strategy to prioritise domestic fertiliser demand, with shipments redirected to markets such as India and Indonesia. The result is a fragmentation of global trade flows and heightened uncertainty for import-dependent producers.

Geographic concentration of risk

The disruption is most acute in northern Chile, particularly in regions around the Atacama Desert, where leaching operations dominate due to the prevalence of oxidised deposits.

This geographic clustering amplifies risk:

• multiple mines competing for limited supply
• pressure on transport and storage systems
• local disruption quickly scaling into a national supply issue

Estimates vary significantly:

• Morgan Stanley: up to 1.1mn tonnes of annual output at risk
• Goldman Sachs: around 200,000 tonnes (≈1% of global supply)

The divergence reflects uncertainty over:

• access to alternative suppliers
• operational flexibility
• inventory buffers

Lower-grade ores add further pressure, as they require more acid per tonne of copper.

Operational constraints intensify

The shortage affects production through several channels:

• Direct disruption: insufficient acid halts leaching
• Cost inflation: higher prices render marginal mines uneconomic
• Logistical bottlenecks: transport and storage limitations
• Technical barriers: alternative acid may require process changes

Because leaching is slower than smelting, impacts may be delayed but prolonged.

Limited replacement options

Domestic production offers only partial relief. While smelters generate sulfuric acid as a by-product, constraints include:

• capacity limits
• need for further [[PRRS_LINK_3]]
• mismatched geographic distribution

State-owned Codelco may benefit from government backing, while private operators remain more exposed to market conditions.

Implications for copper prices

Any sustained disruption in Chile is likely to exert upward pressure on global copper prices:

• Moderate scenario: losses absorbed through inventories
• Severe scenario: supply deficit and sustained price increases

The impact extends across industries reliant on copper:

• renewable energy
• electric vehicles
• construction
• electronics

A broader supply chain warning

The crisis highlights the fragility of interconnected supply chains. A policy decision affecting a single chemical input can reshape production dynamics globally.

Long-term solutions include:

• diversifying supply sources
• expanding domestic capacity
• investing in technologies such as bioleaching and recycling