微波催化氧化降解结晶紫废水及其氧化机理

 针对工业染料废水处理难的问题,采用微波催化氧化降解(MCOD)方法,不添加氧化剂处理结晶紫模拟废水。首先用浸渍法制备CuO/AC 催化剂,采用X 射线衍射(XRD)、傅里叶红外光谱(FT-IR)技术对催化剂样品进行表征。考查CuO 担载量及催化剂用量、微波功率、微波反应时间、催化剂用量、反应液初始质量浓度等因素对结晶紫去除率的影响。结果表明,在微波功率400 W 条件下,使用0.6 g CuO 担载量为质量分数0.8%的微波催化剂CuO/AC,处理100 mL 初始质量浓度为100 mg/L 的结晶紫模拟废水6 min,降解率可达99.48%,相应有机碳去除率为94.01%。通过添加不同氧化基团清除剂的实验发现,反应过程中产生了羟基自由基(·OH)。这种微波催化氧化降解(MCOD)新方法可高效处理结晶紫模拟废水。

Microwave catalytic oxidation degradation of crystal violet over microwave catalyst CuO/AC and its mechanism

As a treatment for the industrial dye wastewater, this paper proposes a novel method of the microwave catalytic oxidation degradation (MCOD) using CuO/AC catalyst, and this novel method is used for the treatment of the crystal violet contaminant as a model wastewater in the aqueous solution without adding oxidant. The activated carbon-supported copper oxide (CuO/AC) is prepared by using the impregnation method and is characterized by using the XRD and the FT-IR. The effects of the metal loadings, the microwave catalyst dosage, the microwave power, the irradiation time and the initial crystal violet concentration on the degradation are investigated. It is shown that the removal rate of the crystal violet reaches up to 99.48%, with the removal rate of TOC being 90.4% under the optimized conditions: 0.8% of the CuO loading, 400 W of the MW power, 0.6 g of the dosage of the microwave catalyst, 6 min of the reaction time, and 100 mg/L of the initial concentration. The experiment of adding several different radical scavengers shows that the hydroxyl radicals (·OH) exist in the reaction process. The results indicate that the microwave catalytic oxidation degradation method could degrade the crystal violet wastewater effectively.