Fe_(1-x)S-BC/g-C_(3)N_(4)的制备及其光芬顿降解盐酸四环素的性能

Fabrication of Fe_(1-x)S-BC/g-C3N4 and its heterogeneous photo-Fenton degradation effect of tetracycline hydrochloride

通过浸渍联合原位煅烧方法成功制备了Fe_(1-x)S-BC/g-C_(3)N_(4)复合光催化材料,采用SEM、XRD、FTIR和XPS对Fe_(1-x)S-BC/g-C_(3)N_(4)催化剂的结构进行表征分析,并将其用于盐酸四环素(TCH)的光芬顿催化降解,考察了三聚氰胺加入量、催化剂投加量、TCH初始浓度、H2O2浓度和初始pH对TCH降解率的影响.结果表明,最佳反应条件为pH=3.0、H2O2=10 mmol·L^(−1)、催化剂投加量为1.0 g·L^(−1),光照1 h后,Fe_(1-x)S-BC/g-C_(3)N_(4)-2对40 mg·L^(−1)的TCH降解率达到98.5%,且铁溶出量仅为0.5 mg·L^(−1).对照实验显示,Fe_(1-x)S-BC/g-C_(3)N_(4)-2的光芬顿催化反应速率常数分别是其光催化反应和非均相芬顿反应的66.6倍和2.9倍.杂离子干扰实验表明Fe_(1-x)S-BC/g-C_(3)N_(4)-2对常见的阴离子有良好的耐受性,经过5次循环使用后,TCH的解率仍有87.1%.活性物种猝灭实验证实·OH和·O2−为主要的活性物种.

In this study,pyrrhotite impregnated biochar which modified by g-C_(3)N_(4)(Fe_(1-x)S-BC/g-C_(3)N_(4))was prepared by one-step pyrolysis process.The structures of the photo-Fenton catalysts were characterized by SEM,XRD,FTIR and XPS,and their removal performance of tetracycline hydrochloride(TCH)were studied.The single factor experiments were carried out to evaluate the effects of melamine addition,catalyst dosage,initial concentration of TCH,H2O2 concentration and initial pH on the degradation efficiency of TCH.The results showed that the optimal photo-Fenton reaction conditions were pH=3.0,concentration of H2O2 is 10 mmol·L−1,and the catalyst dosage is 1.0 g·L^(−1),then the degradation rate of 40 mg·L^(−1)TCH by Fe_(1-x)S-BC/g-C_(3)N_(4)-2 in 1 hour was up to 98.5%,and the leached iron was only 0.5 mg·L^(−1).Control experiments showed that the rate constant of Fe_(1-x)S-BC/g-C_(3)N_(4)-2 in the photo-Fenton catalytic reaction were 66.6 and 2.9 times higher than those in its photocatalytic and heterogeneous Fenton reactions,respectively.The interference experiments indicated that Fe_(1-x)S-BC/g-C_(3)N_(4)-2 had good tolerance to common anions,and the degradation rate of TCH could still reach to 87.1%after 5 cycles of catalytic reaction.The radical trapping experiments proved that·OH and·O2−were the main active species in the photo-Fenton catalytic reaction.