摘要
以硫酸钛为前驱体,尿素为沉淀剂,粗孔微球硅胶为载体,采用水热法在160℃下制备硅胶负载TiO_2(TiO_2/硅胶)光催化剂。通过调节TiO_2含量(15%、30%、40%、55%、70%、85%)和水热时间(2,3,4,5,6 h)制备TiO_2/硅胶光催化剂,并考察了材料的晶体结构、比表面积、TiO_2负载量以及光催化降解腐殖酸性能。结果表明:TiO_2理论投加量为70%,水热时间为5 h时,制备所得的TiO_2/硅胶光催化剂具有最优的光催化活性,此时制备的催化剂为锐钛矿型,比表面积为434.829 m^2/g,TiO_2负载量为37.50%。当使用该催化剂投加量为4 g/L、腐殖酸初始浓度为20 mg/L时,腐殖酸降解率最高,为76.5%,降解过程符合一级反应动力学。催化剂经重复4次使用后,仍具有较好的光催化稳定性。
Titanium sulfate （TiSO4 ） and urea （CO （NH2 ）2 ） were used as raw material, silica was used as supporter to prepare silica gel supported TiO2 （TiOJsilica gel） photocatalyst by hydrothermal method under 160 ℃. In this study, materials were prepared under different TiO2 ratios （15% ,30% ,40% ,55% ,70% ,85% ） together with different hydrothermal times （2,3,4,5,6 h） , and crystal structure, specific surface area, the amount of TiO2 attached on the silica gel of TiOJsilica gel photoeatalysts as well as the degradation rate of humic acid were used as indicators for the properties evaluation. The study demonstrated that the TiO2/silica gel had the best photocatalytie activity when the mass ratio of TiO2 was 70% with hydrothermal time of 5 h, which was anatase with a surface area of 434. 829 m^2/g, and attached an amount of 37.50% by TiO2. The further degradation experiment showed that the degradation rate reached to 76.5% when the applied catalyst dosage was 4 g/L with the initial humic acid concentration of 20 mg/L, and the degradation process fitted the first order kinetics well. Moreover, the catalyst showed reliable photocatalytic activity after four times utilization.
出处
《环境工程》
CAS
CSCD
北大核心
2017年第2期43-48,共6页
Environmental Engineering
基金
中央高校基础科研项目(FRF-IC-15-004)
关键词
TIO2
硅胶
水热法
腐殖酸
TiO2
silica gel
hydrothermal method
humic acid
