羟肟酸功能化PMMA/AM/HOA的合成及对Hg2+和Cd2+的吸附性能

用悬浮聚合法合成了甲基丙烯酸甲酯（MMA）与丙烯酰胺（AM）的共聚物PMMA/AM，再经羟胺改性制备了含羟肟酸功能基的改性PMMA/AM/HOA 树脂。通过红外光谱（FTIR）和热重分析（TG）对PMMA/AM/HOA树脂的结构和稳定性进行了表征。以PMMA/AM/HOA为吸附剂，考察了温度、吸附时间、pH值和金属离子浓度等条件对Hg2+、Cd2+两种金属离子吸附性能的影响。结果表明，改性树脂对Hg2+、Cd2+具有良好的吸附能力，其实验吸附量分别为0.822和0.384 mmol·g-1。改性树脂对Hg2+和Cd2+的吸附过程符合拟二级动力学方程，25℃时其二级动力学吸附速率常数分别为5.301×10-2和3.582×10-2 g·（mmol·min）-1；改性树脂对Hg2+和Cd2+的吸附量随温度的升高有所增大，吸附过程符合Langmuir和Freundlich吸附等温式。

Synthesis of hydroximic acid functionalized PMMA/AM/HOA resin and its adsorbability for Hg2+ and Cd2+

Modification of a copolymer resin, synthesized by suspension polymerization of methacrylic acid and acrylamide monomers, was carried out using hydroamine. Fourier transform infrared spectroscopy (FTIR) and thermogravimetric analysis (TGA) were used to characterize the structure and the stability of the modified resin. The influence of temperature, adsorption time, pH value, and metal ion concentration on the adsorbability of the modified resin towards Hg2+ and Cd2+ was investigated. The modified resin exhibited excellent adsorbability, with the optimal adsorption capacities for Hg2+ and Cd2+ being 0.822 and 0.384 mmol·g-1. The adsorption capacity increased with an increase in adsorption temperature, and the experimental kinetic data correlated with the second-order kinetic model, giving adsorption rate constants for Hg2+ and Cd2+ of 5.301×10-2 and 3.582×10-2 g·(mmol·min)-1, respectively. Finally, the adsorption behavior was in accordance with the Langmuir and Freundlich isotherms.