Selenium and tellurium recovery from copper refinery streams: critical assessment of nanomaterial-integrated processes, pilot-scale performance and circular economy pathways

Selenium and tellurium are critical metalloids underpinning photovoltaic modules, power electronics, and specialty steels, yet copper electrorefining, their principal production route, recovers only 50–60% of selenium and 75–85% of tellurium from anode slimes. Existing reviews address individual recovery methods in isolation; none have integrated next-generation nanomaterial strategies with pilot-scale performance data, advanced process automation, and quantitative life cycle assessment within an industrial circular economy framework. Specifically, this review has a more comprehensive approach when comparing conventional and nanomaterial-based recovery routes than has been done before, extending the expected nanomaterial performance to pilot-scale evidence, connecting measured process control improvements to the overall performance and putting the whole recovery chain within one quantified life cycle assessment and circular economy framework. This review addresses that gap by critically evaluating the full technology spectrum: functionalized metal–organic frameworks and covalent organic frameworks achieving selectivities above 90%, core–shell magnetic nanocomposites enabling field-assisted separation, electrodeposition-redox replacement systems yielding 10–100× surface enrichment factors, and nanofiltration membranes rejecting over 95% of multivalent ions. Comparative life cycle assessment demonstrates that electrochemical recovery routes reduce the global warming potential of selenium production by 24.8% (18.5 vs. 24.6 kg CO₂ eq/kg) and process water consumption by 29.2% (25.5 vs. 36.0 m³/kg) relative to pyrometallurgical baselines. Nanomaterial systems at technology readiness level (TRL) 4–6 and integrated processes at TRL 7–8 define a clear commercialization gap, with scale-up validation, techno-economic modelling, and regulatory harmonization identified as the priorities for achieving sustained recovery efficiencies above 95%.