Researchers at Freiberg University in Germany have developed a hydrogen-based direct reduction process for tin smelting that eliminates carbon emissions while achieving over 99% metal purity. The breakthrough technology uses 3 grams of hydrogen per 100 grams of cassiterite concentrate at 1,300°C, offering a low-carbon alternative to traditional carbon-based tin production methods that have dominated the industry for centuries.
The German team’s work addresses the tin industry’s carbon footprint challenge by replacing conventional carbothermic reduction with hydrogen reduction of cassiterite, the primary tin ore containing tin dioxide. Traditional tin smelting requires high-temperature reduction using carbon-based materials in a two-stage process that generates substantial carbon dioxide emissions. The hydrogen-based approach eliminates these emissions entirely when renewable energy sources power hydrogen production.
Technical Process Demonstrates Commercial Viability
The Freiberg University research team successfully demonstrated that hydrogen can reduce cassiterite to metallic tin while maintaining commercial purity standards. During the reduction process, a slag phase forms containing impurities and approximately 13% tin as tin oxide, which researchers successfully recovered through chemical leaching techniques. This recovery process ensures minimal tin losses while maintaining the environmental benefits of hydrogen-based production.
The 1,300°C operating temperature aligns with existing industrial furnace capabilities, potentially enabling retrofitting of conventional tin smelting facilities. The hydrogen consumption rate of 3% by weight relative to cassiterite concentrate represents a manageable input requirement for industrial-scale operations, particularly as green hydrogen production costs decline through technological advancement and infrastructure expansion.
The German breakthrough parallels broader metallurgical industry adoption of hydrogen-based reduction technologies. Steel producers have invested heavily in hydrogen direct reduction iron projects, with HBIS Group operating a 1.2-million-ton hydrogen steel facility in China that achieves 70% carbon emission reductions compared to traditional blast furnace operations.
Steel Industry Precedent Validates Hydrogen Metallurgy
The steel sector’s hydrogen adoption provides a roadmap for tin industry transformation. HBIS Group’s facility in Zhangjiakou, China, began commercial production in 2023 and supplies low-carbon steel to BMW’s Shenyang plant, demonstrating industrial-scale hydrogen metallurgy viability. The Chinese steelmaker’s success includes capturing 125 kilograms of carbon dioxide per ton of direct reduced iron production while cutting overall emissions by 800,000 tons annually.
JSW Energy in India has committed to green hydrogen production for steel applications, with a 3,800-ton annual capacity pilot project scheduled for March 2025 operations. The Indian company signed a seven-year contract with JSW Steel to supply green hydrogen and oxygen for steel production, with expansion plans targeting 90,000 tons of green hydrogen annually by 2030.
European steel producers have allocated nearly 3 billion euros in subsidies for hydrogen-based steel projects, though most facilities will initially operate using natural gas before transitioning to renewable hydrogen as infrastructure develops. The transition timeline depends on achieving hydrogen costs of $2-3 per kilogram, down from current green hydrogen prices of $4-8 per kilogram.
Tin Market Dynamics Support Low-Carbon Innovation
Global tin consumption reached 282.5 kilotons in 2024, with market analysts projecting 2.1% annual growth through 2032 to reach 333.6 kilotons. China dominates global tin production at 68,000 metric tons annually, followed by Myanmar at 54,000 metric tons and Indonesia as the third-largest producer. The concentrated production geography creates supply chain vulnerabilities that hydrogen-based technologies could help address through distributed manufacturing capabilities.
Tin prices have demonstrated volatility throughout 2024, reaching $35,575 per metric ton in April before stabilizing around $28,000 per metric ton. The International Tin Association projects potential supply deficits of 13,000 tons by 2030 without additional mining investment, creating market conditions favorable to innovative production technologies that can utilize lower-grade ores or improve processing efficiency.
Approximately 50% of global tin consumption occurs in soldering applications essential for electronics manufacturing, including semiconductors, mobile phones, and electric vehicle components. An additional 17% serves chemical applications, while 12% goes to tinplate production for food packaging and corrosion-resistant coatings. These applications are experiencing growth driven by electrification trends and renewable energy infrastructure development.
Environmental Impact and Industry Transformation
Traditional tin smelting generates substantial carbon emissions through carbothermic reduction processes that consume coal or coke as reducing agents. Aurubis, a major European tin producer, reports a carbon footprint of 3,000 kilograms of carbon dioxide per ton of tin production, significantly below the industry average of 6,632 kilograms per ton through recycling-based operations and energy efficiency improvements.
The hydrogen-based approach developed at Freiberg University could further reduce tin production emissions when powered by renewable energy sources. The technology’s success depends on green hydrogen availability and cost competitiveness with conventional reduction methods. Current hydrogen prices remain above economic thresholds for widespread adoption, but declining renewable energy costs and improving electrolysis efficiency are driving hydrogen costs toward commercial viability.
Indonesia, the world’s third-largest tin producer, has experienced supply disruptions due to regulatory investigations and illegal mining crackdowns, highlighting the need for production technology innovations that can maintain supply stability while meeting environmental standards. The country’s refined tin exports increased 130.8% through April 2025 as authorities concluded corruption investigations, but long-term supply security requires sustainable production methods.
Company Background and Market Context
Freiberg University is a German technical university specializing in mining, metallurgy, and materials science education and research. Founded in 1765, the institution has a long history of metallurgical innovation and maintains close relationships with global mining and metals companies. The university’s Institute of Nonferrous Metallurgy conducts research on sustainable metal production technologies, including alternative reduction processes for various metals. Freiberg University’s work on hydrogen-based tin smelting represents part of broader European Union initiatives to develop low-carbon industrial technologies.
The International Tin Association serves as the global trade organization representing tin producers, consumers, and traders worldwide. The association promotes sustainable tin production practices and provides market analysis, technical research, and industry advocacy. Member companies account for the majority of global primary tin production and are increasingly focused on environmental sustainability and supply chain transparency. The organization’s research initiatives include lifecycle assessments of tin production and promotion of responsible sourcing practices.
Tin remains essential for global electronics manufacturing and renewable energy infrastructure, with demand growth driven by electric vehicle adoption, solar panel production, and semiconductor expansion. The metal’s unique properties make it irreplaceable in soldering applications, while its corrosion resistance ensures continued demand in packaging and chemical applications. Hydrogen-based production technologies could help meet growing demand while addressing environmental concerns about traditional smelting methods.
