Lithium Universe (ASX: LU7) has completed the detailed process flow sheet for a novel hydrometallurgical technology licensed from the University of Edinburgh to extract gold and copper from electronic waste. The low-temperature, reagent-recycling method aims to disrupt traditional smelting with environmental and cost benefits.
- Exclusive global licence for University of Edinburgh GCDE technology
- Selective gold precipitation using reusable diamide ligand
- Copper recovery via pyrazine-2,3-dicarboxylic acid reagent
- Lower energy hydrometallurgical process than smelting
- Strong commercial potential in circular economy and e-waste recycling
Breakthrough Hydrometallurgical Process for E-Waste Metals
Lithium Universe Limited (ASX:LU7) has unveiled the completed process flow sheet for an innovative technology designed to extract gold and copper from electronic waste (e-waste) using a low-temperature hydrometallurgical method. Licensed exclusively from the University of Edinburgh, the Gold Copper Diamide Extraction (GCDE) process employs selective, reusable organic reagents to precipitate precious metals, sidestepping the energy-intensive smelting that dominates current recycling.
The technology’s core innovation lies in its use of a tertiary diamide ligand to selectively precipitate gold from acidic chloride leach solutions, followed by copper recovery using pyrazine-2,3-dicarboxylic acid (2,3-PDCA). This approach reduces energy consumption and environmental impact, positioning LU7 to tap into the rapidly growing circular economy sector driven by surging global e-waste volumes.
Detailed Multi-Step Recovery Process
The GCDE process begins with mechanical preprocessing and washing of e-waste feedstock, typically printed circuit board powder, to remove impurities that could hinder metal recovery. Gold and copper are then dissolved via chloride leaching, with two options: an environmentally benign hydrochloric acid and hydrogen peroxide leach, or a traditional aqua regia leach.
Following leaching, the solution’s acidity is adjusted to optimise selective gold precipitation. The diamide ligand forms supramolecular structures that selectively bind tetrachloroaurate ions, enabling gold to be recovered as a high-purity metallic product after chemical reduction. The ligand is then stripped and recycled, maintaining reagent efficiency and lowering operating costs.
Copper recovery proceeds from the gold-depleted liquor, where 2,3-PDCA forms a stable copper complex that precipitates as a distinctive blue solid. This copper complex can be converted into copper sulfide or further refined via electrowinning, with the ligand regenerated for reuse. Residual base metals remain in solution for potential further recovery or neutralisation.
Strategic Expansion into Sustainable Recycling
Chief Technical Officer Dr Jingyuan Liu led the process design, while CEO Iggy Tan highlighted the milestone as a significant step in LU7’s expansion beyond lithium refining. The company is also advancing silver recovery from photovoltaic solar panels and developing lithium refineries in North America, aiming to close critical materials supply chain gaps.
This technology offers a compelling alternative to conventional smelting, especially for smaller-scale operations where capital intensity and energy use are barriers. Its reagent recyclability and ambient temperature operation align with sustainability imperatives, potentially offering LU7 a competitive edge in the burgeoning e-waste recycling market.
While pilot plant construction and commercial validation remain forthcoming, the completed flow sheet lays a solid foundation for scale-up and regulatory approvals. The unfolding story will be how quickly LU7 can translate this technical blueprint into operational success amid rising demand for recycled critical metals.
Bottom Line?
LU7’s GCDE process positions it at the forefront of sustainable e-waste metal recovery, but commercial viability hinges on successful pilot scale demonstration and market adoption.
Questions in the middle?
- How will pilot plant results validate the GCDE process’s recovery rates and operating costs?
- What regulatory hurdles might LU7 face in deploying this novel hydrometallurgical technology at scale?
- Can LU7 secure commercial partnerships to accelerate adoption within the circular economy sector?