海藻酸钠固定化纳米铁还原脱色活性红X3B

采用海藻酸钠固定纳米铁制备海藻酸钠纳米铁小球，研究了海藻酸钠浓度、纳米铁含量、活性红X3B浓度、反应温度、pH值等对海藻酸钠固定化纳米铁小球还原活性红X3B的影响.采用高效液相色谱（HPLC）、紫外可见分光光度计（UV-Vis）、扫描电镜（SEM）、透射电镜（TEM）等方法分析污染物的还原脱色过程.结果表明，X3B的还原脱色获得了较好的效果，当温度25.0℃，海藻酸钠浓度2.0%，纳米铁含量2.0g/L，转速200r/min，pH值10.9时，反应720min后，25.0mg/L活性红X3B的脱色率达98.9%.海藻酸钠凝胶对活性红X3B没有吸附作用，海藻酸钠固定化纳米铁小球降解活性红X3B的主要机制为纳米零价铁的还原作用.

Reductive decolorization of azo-dye X3B by sodium alginate immobilized iron nanoparticles

Sodium alginate (SA) immobilized nanoscale zero-valent iron (nZVI) was synthesized and applied to reduce the azo dye (reactive red X3B) in water. The effects of SA concentration, nZVI dosage, reactive red X3B initial concentration, temperature, and initial pH on removal efficiency were investigated, respectively. High performance liquid chromatography (HPLC), UV-vis spectrophotometer (UV-Vis), scanning electron microscopy (SEM), and transmission electron microscope (TEM) were employed to analyze the reductive decolorization process of the target pollutant by the nanocomposites. As high as 98.9% reactive red X3B were removed after 720min (T=25℃, pH=10.9, 200r/min, 2.0g/L nZVI with 2.0wt% SA loading, and 25.0mg/L X3B). The adsorption of reactive red X3B by sodium alginate gel was not observed, and the main mechanism of reactive red X3B decolorization was attributed to the reactive red X3B reduction by nZVI.