交联壳聚糖/Cu_2O复合颗粒可见光催化脱色活性艳红

利用壳聚糖对金属离子的吸附和螯合作用,通过简单的液相沉淀-还原过程一步原位合成了交联壳聚糖/Cu2O复合粒子。X射线衍射(XRD)和红外(FT-IR)测试结果表明,壳聚糖与Cu2O纳米微粒能有效复合。以活性艳红X-3B溶液为模拟印染废水,采用Langmuir-Hinshelwood假一级方程模拟交联壳聚糖/Cu2O复合粒子光催化脱色反应的动力学行为,从动力学角度系统研究染料初始浓度、反应体系pH、催化剂用量和反应体系气氛等因素对复合粒子可见光催化脱色反应速率的影响。结果表明,当染料溶液浓度较低时,光催化过程可视为假一级反应。降低活性艳红X-3B初始浓度和pH,增加催化剂用量和反应体系的含O2量都可显著增加光解脱色反应速率常数。相同条件下,与纯Cu2O相比,交联壳聚糖/Cu2O复合粒子对X-3B呈现出更好的吸附性和更高的可见光催化活性。

Photocatalytic decolorization of reactive brilliant red by cross-linked chitosan/Cu2O composite particles

Aimed at adsorption and chelating ability with metal ions of chitosan,cross-linked chitosan/Cu₂O composite particles were in situ prepared via a simple one-step liquid phase precipitation-reduction process.XRD and FT-IR spectra of chitosan,pure Cu₂O and the composites indicated that Cu₂O and chitosan were connected together successfully.Reactive brilliant red X-3B(X-3B) was used as model pollutant to study the photocatalytic decolorization of the composites.Based on Langmuir-Hinshelwood kinetic equation,the effect of initial dye concentration,initial pH,catalyst amount,reaction atmosphere on X-3B decolorization rate was investigated.The results showed that the photocatalytic decolorization process on cross-linked chitosan/Cu₂O composites followed apparent pseudo-first-order kinetics model under low dye concentration.A lower initial X-3B concentration and pH,and a higher catalyst dose and amount of O₂ circulated through X-3B solution could result in a faster decolorization rate.Cross-linked chitosan/Cu₂O composites exhibited enhanced adsorption and visible-light photocatalytic activity compared with pure Cu₂O under the same experimental conditions.