Macena Morgana, Pereira Helena, Grosche Lucas, Esteves Bruno, Santos-Vieira Isabel, Cruz-Lopes Luísa
CERNAS Research Centre, Polytechnic Institute of Viseu, 3504-510 Viseu, Portugal.
CEF-Forest Research Centre, School of Agriculture, University of Lisbon, 1349-017 Lisboa, Portugal.
Materials (Basel). 2025 May 16;18(10):2320. doi: 10.3390/ma18102320.
Water pollution by toxic metals, especially by lead ions, is a serious environmental concern due to these metals' persistence, bioaccumulation, and toxicity. Aiming to reduce metal concentrations to non-toxic levels, this study analyzed the removal of lead from water through adsorption with bio-adsorbents. The adsorbent potential of the following four lignocellulosic byproducts were tested: walnut and chestnut shells, pine wood, and burnt pine wood. Removal rates of 97-99% were achieved at optimized conditions, i.e., at a pH of approximately 7, adsorbent dose of 4 g L, and 12 h of reaction. The BET specific surface area was between 1.74 and 4.85 m g. The pore size of the wood bio-adsorbent was 26.54 nm, and those of the remaining materials were between 5.40 and 7.33 nm. With R = 0.998-1.000, the kinetics fit the pseudo-second-order model better, suggesting that chemisorption is the dominant mechanism. Both Langmuir and Freundlich isothermal models fit the data well, with R = 0.946-0.999. It can be concluded that all the bio-adsorbents tested have the potential to efficiently remove lead ions from water.
有毒金属造成的水污染，尤其是铅离子污染，是一个严重的环境问题，因为这些金属具有持久性、生物累积性和毒性。为了将金属浓度降低到无毒水平，本研究分析了通过生物吸附剂吸附从水中去除铅的情况。测试了以下四种木质纤维素副产品的吸附潜力：核桃壳、栗子壳、松木和烧松木。在优化条件下，即pH值约为7、吸附剂剂量为4 g/L和反应12小时，去除率达到了97%至99%。BET比表面积在1.74至4.85 m²/g之间。木质生物吸附剂的孔径为26.54 nm，其余材料的孔径在5.40至7.33 nm之间。相关系数R = 0.998 - 1.000，动力学更符合准二级模型，表明化学吸附是主要机制。Langmuir和Freundlich等温模型都能很好地拟合数据，相关系数R = 0.946 - 0.999。可以得出结论，所有测试的生物吸附剂都有潜力从水中有效去除铅离子。
