Heavy metal pollution caused by the indiscriminate disposal of toxic heavy metal wastewater has become one of the serious water environmental issues. In this study, a novel NH₂-PAA/Alginate hydrogel with double network interpenetrating structure was constructed with alginate, acrylic acid, and other raw materials. Characterized by scanning electron microscope, this hydrogel shows a three-dimensional porous structure, which would be useful in adsorption process for its high diffusion coefficient. The results of adsorption experimental show that the NH₂-PAA/Alginate possessed the well adsorption capacity when pH was above 3.5, the maximum adsorption capacity calculated by Langmuir was 176.5 mg/g, and the adsorption equilibrium can be achieved within 150 min. In addition, the NH₂-PAA/Alginate has good recycling ability and stability. The results of X-ray photoelectron spectroscope analysis reveal that the Cd(II) exchanged with Ca(II) and then coordinated with amino and hydroxyl groups in NH₂-PAA/Alginate. The NH₂-PAA/Alginate hydrogel can deal with all kinds of heavy metal ions and is a potential material for heavy metal adsorption.

中文翻译：

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使用具有双网络互穿结构的氨基官能化水凝胶捕获镉 (II)：吸附行为研究

有毒重金属废水乱排放造成的重金属污染已成为严重的水环境问题之一。本研究以海藻酸盐、丙烯酸等为原料，构建了一种具有双网络互穿结构的新型NH _{2 -PAA/海藻酸盐水凝胶。}通过扫描电子显微镜表征，该水凝胶显示出三维多孔结构，其高扩散系数可用于吸附过程。吸附实验结果表明，NH ₂ -PAA/海藻酸盐在pH大于3.5时具有良好的吸附能力，Langmuir计算的最大吸附能力为176.5 mg/g，150 min内即可达到吸附平衡。此外，NH₂ -PAA/Alginate具有良好的回收能力和稳定性。X射线光电子能谱分析结果表明Cd(II)与Ca(II)发生交换后与NH ₂ -PAA/Alginate中的氨基和羟基配位。NH ₂ -PAA/海藻酸盐水凝胶可以处理各种重金属离子，是一种潜在的重金属吸附材料。