摘要
以乙酸锌、乙酸镉和柠檬酸三钠为原料,采用沉淀法制备一系列不同Cd掺杂量的花状Cd-ZnO复合光催化材料,并系统研究催化剂投加量、盐酸四环素(TC)初始浓度、初始pH、反应时间等对Cd-ZnO复合光催化材料催化降解TC性能的影响。结果表明,掺杂适量Cd后ZnO对光的吸收边带发生红移,禁带宽度变窄,光谱响应区域拓宽。在TC初始质量浓度30 mg/L、催化剂投加质量浓度0.6 g/L、初始pH=6.2条件下,催化剂Cd_(0.5)ZnO对TC的催化降解效果达最优,在紫外光照射120 min时体系对四环素的去除率达到85.3%。动力学研究表明,Cd-ZnO复合光催化材料对TC的催化降解行为符合准二级动力学规律,反应过程中h^(+)是主要的活性物种,·OH也发挥了较大的作用。复合催化剂Cd_(0.5)ZnO在循环使用4次后,体系对TC的降解率仅下降2.2%,表明Cd_(0.5)ZnO是一种重复使用效率高且稳定性较好的光催化剂。
Zinc acetate,cadmium acetate and trisodium citrate were used as raw materials to prepare a series of flower-like Cd-ZnO composites with different Cd doping amounts by precipitation method.The effects of catalyst dosage,initial concentration of tetracycline hydrochloride(TC),initial pH,and reaction time on the catalytic degra⁃dation performance of Cd-ZnO composite photocatalytic materials for TC were systematically evaluated.The results showed that the absorption sideband of ZnO doped with Cd had a red shift,the band gap was narrowed,and the spec⁃tral response area was enhanced.Under the conditions of initial tetracycline mass concentration of 30 mg/L,catalyst dosage of 0.6 g/L,initial pH=6.2,the catalyst Cd_(0.5)ZnO had the optimum degradation effect and the removal rate of tetracycline reached 85.3%after 120 minutes of UV irradiation.Kinetic studies showed that the degradation behav⁃ior of Cd-ZnO composite photocatalytic materials on TC followed a quasi second-order kinetic law.During the reac⁃tion process,h+was the main active species,and·OH also played a significant role.The composite catalyst Cd_(0.5)ZnO could only reduce the TC degradation rate by 2.2% after four photocatalytic cycles,which was a kind of photocata⁃lyst with high reuse efficiency and good stability.
作者
张化冰
杜焱
孙厚祥
ZHANG Huabing;DU Yan;SUN Houxiang(School of Biological and Chemical Engineering,Panzhihua University,Panzhihua 617000,China)
出处
《工业水处理》
CAS
CSCD
北大核心
2023年第7期120-127,共8页
Industrial Water Treatment
基金
四川省大学生创新创业训练项目(S202111360074)
攀枝花学院校级培育项目(2020ZD017)。
关键词
氧化锌
镉掺杂
光催化
盐酸四环素
zinc oxide
cadmium⁃doped
photocatalytic
tetracycline hydrochloride
