The State Key Laboratory of Refractories and Metallurgy, Wuhan University of Science and Technology, Wuhan, Hubei 430081, China; Key Laboratory for Ferrous Metallurgy and Resources Utilization of Ministry of Education, Wuhan University of Science and Technology, Wuhan, Hubei 430081, China.
The State Key Laboratory of Refractories and Metallurgy, Wuhan University of Science and Technology, Wuhan, Hubei 430081, China; Key Laboratory for Ferrous Metallurgy and Resources Utilization of Ministry of Education, Wuhan University of Science and Technology, Wuhan, Hubei 430081, China.
Int J Biol Macromol. 2022 Sep 1;216:882-890. doi: 10.1016/j.ijbiomac.2022.07.226. Epub 2022 Aug 1.
Amine/quaternary ammonium lignin for adsorption of tungsten was synthesized by amination and quaternization from lignin. The adsorbent was characterized by SEM-EDS and FTIR. The effects of pH, initial concentration of tungsten, adsorption time and dosage of adsorbent on the adsorption effect were investigated. The adsorption mechanism was revealed by SEM-EDS and FTIR and XPS. The results showed that amine/quaternary ammonium lignin was loose and rough and contained a large number of phenolic hydroxyl and amine and quaternary ammonium functional groups. Using the optimum conditions, which included the pH of 4.0 and initial tungsten concentration of 800 mg·L and adsorption time of 960 min, the saturated adsorption capacity of 1 g·L amine/quaternary ammonium lignin for tungsten reached 421.68 mg·g. The adsorption followed Langmuir model and quasi-second-order kinetic model, indicating that the adsorption was monolayer homogeneous chemisorption. When the total concentration of tungsten was 0.005 mol·L and the value of pH was smaller than 4.7, HWO was the existing form of tungsten and was adsorbed by electrostatic attraction of hydrogen bond and coordination with amino and ion exchange with Cl.
胺/季铵化木质素通过木质素的胺化和季铵化合成，用于吸附钨。通过 SEM-EDS 和 FTIR 对吸附剂进行了表征。考察了 pH、钨的初始浓度、吸附时间和吸附剂用量对吸附效果的影响。通过 SEM-EDS 和 FTIR 以及 XPS 揭示了吸附机理。结果表明，胺/季铵化木质素疏松粗糙，含有大量的酚羟基、胺基和季铵基官能团。在最佳条件下（pH 为 4.0，初始钨浓度为 800mg·L，吸附时间为 960min），1g·L 胺/季铵化木质素对钨的饱和吸附容量达到 421.68mg·g。吸附符合 Langmuir 模型和拟二级动力学模型，表明吸附是单层均相化学吸附。当钨的总浓度为 0.005mol·L，pH 值小于 4.7 时，HWO 是钨的存在形式，通过氢键的静电吸引、与氨基的配位和与 Cl 的离子交换进行吸附。
