Gold recovery through synergetic adsorption and reduction using acid–base additive-reinforced tubular carbon nanofibers

In response to the increasing demand for gold in electronic manufacturing, this study addresses the urgent need for gold recycling from electronic waste (E-waste) to ensure the environment and energy safety. This study focuses on the preparation of the tubular carbon nanofibers (TCNFs) integrating -NH₄⁺ and -SO₃⁻ groups into TCNF-SO₃⁻-NH₄⁺, which exhibited remarkable gold adsorption capacity (2003.25 ± 0.23 mg/g) and selectivity (K_d; 41.7 × 10³ mL/g) at lower pH. TCNF-SO₃⁻-NH₄⁺ achieved a 99.77% gold adsorption efficiency under lower pH conditions (pH = 1) from E-waste. The adsorption capacity reached 3.54 ± 0.11 mg/g at an initial concentration of 0.85 mg/L. The results highlight the efficacy of TCNF-SO₃⁻-NH₄⁺ for extracting gold and other precious metal ions from E-waste, presenting a promising solution for clean energy and environmental protection.