A new generation solvent extraction diluent derived from natural gas is drawing interest in the hydrometallurgy sector. Shell GTL G80, developed by Shell plc, has recently been evaluated as a synthetic alternative to traditional mineral-oil-based diluents used in copper solvent extraction circuits.
Unlike conventional petroleum-derived diluents, GTL G80 is produced from natural gas using the Fischer–Tropsch process, which converts synthesis gas into highly pure paraffinic hydrocarbons. The resulting solvent consists mainly of linear and lightly branched paraffins in the C9–C16 range with extremely low levels of sulfur, olefins, and aromatic compounds.
Recent laboratory studies investigated the performance of GTL G80 in copper solvent extraction using common extractants such as LIX® 984N and ACORGA® reagents. The results demonstrated fast extraction and stripping kinetics, good phase disengagement, and high copper loading capacity, all of which are key operational parameters in industrial SX–EW plants.
Researchers also observed excellent selectivity for copper over iron, with Cu/Fe separation factors exceeding typical industrial requirements. Despite having very low aromatic content (<400 ppm), the solvent achieved copper loading performance comparable to conventional diluents used in hydrometallurgical plants.
In addition to extraction performance, the synthetic diluent showed operational advantages such as low vapor pressure, high flash point (around 84 °C), and lower evaporation rates compared with common hydrocarbon diluents. These characteristics could reduce solvent losses and improve safety in large-scale solvent extraction operations.
As hydrometallurgical processing expands—particularly for copper, nickel, cobalt, and battery recycling feedstocks—there is increasing interest in more stable and environmentally compatible organic phases. Synthetic GTL diluents such as G80 may offer an alternative to traditional kerosene-based solvents, with potential benefits for process efficiency, solvent stability, and environmental performance.
References
Li, X.; Rivera-Torrente, M.; Deferm, C.; Jones, P. T.; Binnemans, K. “Shell GTL Fluid G80: A New Synthetic Aliphatic Diluent for Solvent Extraction of Copper.” Journal of Sustainable Metallurgy, 11, 2688–2702 (2025).
Li, X.; Rivera-Torrente, M.; Deferm, C.; Jones, P. T.; Binnemans, K. “Shell GTL Fluid G80: A New Synthetic Aliphatic Diluent for Solvent Extraction of Copper.” Research portal, University of Groningen (2025).
Shell plc. Shell GTL Performance Fluids – Technical overview and mining solvent extraction applications.
