论文部分内容阅读
利用酸催化的溶胶-凝胶法成功地合成了一系列不同Cr3+掺杂量(x=0.01%~10%)的TiO2复合光催化剂(Cr3+/TiO2)。在太阳光条件下,以亚甲基蓝溶液的光催化降解对复合材料的光催化性能进行了表征,并考察了催化剂投加量、Cr3+掺杂量和溶液pH值等因素对光催化降解反应的影响。结果表明,亚甲基蓝溶液在复合微粒上的光催化降解反应遵循Langmuir-Hinshelwood动力学模型,在催化剂投加量为1g/L、Cr3+掺入量为0.3%和pH=7时,Cr3+/TiO2复合微粒光催化活性达最佳,测得表观反应速率常数K为7.27×10-3mg(L.min)-1,t1/2为95min,反应4h后亚甲基蓝的降解率可达79%,与纯的TiO2相比较,反应速率提高了2倍,降解率提高了20%。中性或碱性条件下有利于亚甲基蓝溶液的光催化降解。
A series of Cr3 + / TiO2 composite photocatalysts (x = 0.01% ~ 10%) have been successfully synthesized by acid-catalyzed sol-gel method. The photocatalytic performance of the composites was characterized by photocatalytic degradation of methylene blue solution under sunlight. The effects of catalyst dosage, Cr3 + doping concentration and solution pH on the photocatalytic degradation reaction were investigated. The results showed that the photocatalytic degradation of methylene blue solution on the composite particles followed the Langmuir-Hinshelwood kinetics model. When the catalyst dosage was 1 g / L, the amount of Cr3 + was 0.3% and pH = 7, the Cr3 + / TiO2 composite particles The apparent reaction rate constant K was 7.27 × 10-3mg (L.min) -1 and t1 / 2 was 95min. After 4 hours reaction, the degradation rate of methylene blue reached 79% TiO2, the reaction rate increased by 2 times, the degradation rate increased by 20%. Neutral or alkaline conditions favor the photocatalytic degradation of methylene blue solution.