染料废水的纳米二氧化钛/壳聚糖复合物处理

Dye wastewater treatment with nano TiO_2/chitosan complex

以纳米二氧化钛，壳聚糖复合物为絮凝剂处理染料废水。考察了pH值、纳米二氧化钛／壳聚糖用量和光催化反应时间对脱色率和COD去除率的影响，比较了纳米二氧化钛、壳聚糖和纳米二氧化钛／壳聚糖处理染料废水的效果。结果表明，纳米二氧化钛／壳聚糖的脱色效果和COD去除率明显优于单一使用壳聚糖或纳米二氧化钛，优化工艺为：pH值7～8，纳米二氧化钛，壳聚糖投加质量浓度为350mg／L，光催化反应时间120min。优化工艺条件下，脱色率可达96．89％，COD去除率可达94．03％，处理后废水的各项指标达到国标排放标准。

The dye wastewater is treated using nano TiO2/chitosan complex as flocculants. The influence of pH value, concentration of nano TiO2/chitosan complex, photocatalytic reaction time on color and chemical oxygen demand （COD） removal are investigated. The effects of nano-TiO2, chitosan and nano TiO2/chitosan complex are compared. The results show that dye wastewater treated with nano TiO2/chi- tosan complex has higher color and COD removal rates than those treated with single chitosan or nano- TiO2. The optimized process is pH value 7 ～ 8, nano TiO2/chitosan complex 350 mg/L, photocatalytic time 120 min. Under the optimum conditions, the removal rates of color and COD reach 96,89% and 94.03% respectively. The indicators of the treated wastewater can meet the discharge standard.