Selective copper recovery from ammoniacal waste streams using a systematic biosorption process. (January 2022)

• Record Type: Journal Article
• Authors: Nicomel, Nina Ricci; Otero-Gonzalez, Lila; Williamson, Adam; Ok, Yong Sik; Van Der Voort, Pascal; Hennebel, Tom; Du Laing, Gijs
• Is Part Of: Chemosphere. Volume 286:Part 3(2022)
• Publication Date: 2022-01
• Subjects: Copper -- Ammonia -- Adsorption -- Waste processing -- Selectivity; Pollution -- Periodicals; Pollution -- Physiological effect -- Periodicals; Environmental sciences -- Periodicals; Atmospheric chemistry -- Periodicals; 551.511
• DOI: 10.1016/j.chemosphere.2021.131935
• Languages: English
• ISSNs: 0045-6535

Abstract

Abstract: Cu–NH3 bearing effluents arise from electroplating and metal extraction industries, requiring innovative and sustainable Cu recovery technologies to reduce their adverse environmental impact. CO3 2− and Zn are often co-occurring, and thus, selective Cu recovery from these complex liquid streams is required for economic viability. This study assessed 23 sustainable biosorbents classified as tannin-rich, lignin-rich, chitosan/chitin, dead biomass, macroalgae or biochar for their Cu adsorption capacity and selectivity in a complex NH3 -bearing bioleachate. Under a preliminary screen with 12 mM Cu in 1 M ammoniacal solution, most biosorbents showed optimal Cu adsorption at pH 11, with pinecone remarkably showing high removal efficiencies (up to 68%) at all tested pH values. Further refinements on select biosorbents with pH, contact time, and presence of NH3, Zn and CO3 2− showed again that pinecone has a high maximum adsorption capacity (1.07 mmol g −1 ), worked over pH 5–12 and was Cu-selective with 3.97 selectivity quotient ( K Cu/Zn ). Importantly, pinecone performance was maintained in a real Cu/NH3 /Zn/CO3 2− bioleachate, with 69.4% Cu removal efficiency. Unlike synthetic adsorbents, pinecones require no pre-treatment, which together with its abundance, selectivity, and efficiency without the need for prior NH3 removal, makes it a competitive and sustainable Cu biosorbent for complex Cu–NH3 bearing streams. Overall, this study demonstrated the potential of integrating bioleaching and biosorption as a clean Cu recovery technology utilizing only sustainable resources (i.e., bio-lixiviant and biosorbents). This presents a closed-loop approach to Cu extraction and recovery from wastes, thus effectively addressing elemental sustainability. Highlights: A top-down approach optimized Cu biosorption from a real Cu–NH3 leachate. Pinecone (PC) has a high Cu q max of 1.1 mmol g −1 despite 2 M NH3 and 5 mM Zn present. PC works over wide pH range (5−12) relevant for treating (NH4 )2 CO3 rich effluents. PC has a selectivity quotient ( K Cu/Zn ) of 3.97 making it selective for Cu over Zn. The presence of Zn can improve the q max of PC for Cu from NH3 -rich streams.