针对碱木质素对水溶液中金属离子去除能力有限、难以直接作为重金属离子吸 附剂的现状，对其进行磷酸化改性． 采用红外光谱、颗粒电荷分析、扫描电镜、原子吸收光 谱等方法研究改性木质素对 Pb²⁺ 的吸附性能及相关机理． 结果表明:改性后的木质素表 面粗糙多孔，比表面积由 2． 12m² /g 增加至 11． 17m² /g，能快速吸附 Pb²⁺ 且性能明显优于 原碱木质素，其主要是通过磷酸根、酚羟基、羧基等带负电荷官能团与 Pb²⁺ 的静电作用， 以及分子中的 H⁺ 与 Pb²⁺的离子交换作用进行吸附;磷酸化木质素对 Pb²⁺ 的去除性能主 要受投加量、Pb²⁺ 初始质量浓度、pH 值和温度的影响;随着木质素投加量和溶液 pH 值的 增大，磷酸化木质素对 Pb²⁺ 的去除率升高，在 30℃下对 Pb²⁺ 的去除率达 92． 36%．

Due to its limited adsorption capacity for metal ions in aqueous solutions,alkali lignin is unsuitable for direct industry application as an absorbent of heavy metals.In this paper,a phosphorylation modification of alkali lignin was carried out,and the adsorption capacity of the phosphorylated alkali lignin (PAL) for Pb²⁺ was investi- gated by means of IR,particle charge detection,SEM and atomic absorption spectroscopy,followed with a mecha- nism exploration.The results indicate that (1) after the phosphorylation,the surface of lignin becomes coarse and porous,the specific surface area increases from 2. 12 to 11. 17m² /g,and the adsorption process becomes fast,with a higher adsorption capacity of Pb²⁺ ; (2) the adsorption mainly depends on the electrostatic interaction between Pb²⁺ and such negative functional groups as phosphate,phenolic hydroxyl and carboxyl,as well as on the ion ex- change between H⁺ and Pb²⁺ ; (3) the Pb²⁺ removal capacity of PAL is mainly affected by the PAL mass,the ini- tial mass concentration of Pb²⁺ ,the pH value and the temperature; and (4) the Pb²⁺ removal increases with the increase of PAL mass and pH value,and reaches the maximum 92. 36% at 30℃.