Department of Civil and Environmental Engineering, Faculty of Engineering, The University of Auckland, Private Bag 92019, Auckland 1142, New Zealand.
Department of Civil and Environmental Engineering, Faculty of Engineering, The University of Auckland, Private Bag 92019, Auckland 1142, New Zealand.
J Hazard Mater. 2017 Jan 5;321:868-878. doi: 10.1016/j.jhazmat.2016.10.006. Epub 2016 Oct 4.
Magnetisation of carbonaceous adsorbent using iron oxide (FeO) has potential to decrease the recovery cost of spent adsorbent because it could be separated magnetically. However, formation of various phases of FeO and iron hydroxide (Fe(OH)) during synthesis particularly the non-magnetic phases are difficult to control and could significantly reduce the magnetic saturation of the adsorbent. Hence, formation of the most magnetic FeO, FeO on biochar via oxidative hydrolysis of FeCl under alkaline media was performed to synthesise magnetic adsorbent using pine sawdust biochar (magnetic pine sawdust biochar: MPSB). The FeO nanoparticles on the surface of biochar contributed to high saturation magnetisation of MPSB, 47.8Am/kg, enabling it to be separated from aqueous solution using a magnet. MPSB were examined physically and chemically using various techniques. Sorbent-stability, parametric, kinetics, isotherm, thermodynamic and sorbent-regeneration studies were performed to comprehend the potential of MPSB as adsorbent to remove an emerging contaminant, sulfamethoxazole (SMX) from aqueous solution. Results showed that MPSB was stable within solution pH 4-9. Adsorption of SMX onto MPSB was favourable at low pH, fast and best described by Redlich-Peterson model. Adsorption was exothermic with physisorption possibly due to hydrophobic interaction and spent adsorbent could be regenerated by organic solvents.
使用氧化铁 (FeO) 对碳质吸附剂进行磁化具有降低废吸附剂回收成本的潜力，因为它可以通过磁性分离。然而，在合成过程中各种 FeO 和氢氧化铁 (Fe(OH)) 相的形成，特别是非磁性相的形成难以控制，这可能会显著降低吸附剂的磁饱和。因此，通过在碱性介质中氧化水解 FeCl 来合成生物炭上的最具磁性的 FeO，即 FeO 来合成磁性吸附剂，使用松木锯末生物炭 (磁性松木锯末生物炭：MPSB)。FeO 纳米颗粒在生物炭表面的存在导致 MPSB 具有高饱和磁化强度，为 47.8Am/kg，使其能够通过磁铁从水溶液中分离出来。使用各种技术对 MPSB 进行了物理和化学检查。进行了吸附剂稳定性、参数、动力学、等温线、热力学和吸附剂再生研究，以了解 MPSB 作为吸附剂从水溶液中去除新兴污染物磺胺甲恶唑 (SMX) 的潜力。结果表明，MPSB 在溶液 pH 值 4-9 范围内稳定。SMX 吸附到 MPSB 上在低 pH 值下是有利的，快速且最符合 Redlich-Peterson 模型描述。吸附是放热的，可能是由于物理吸附过程中的疏水相互作用，且废吸附剂可以用有机溶剂再生。
