摘要
以松针为原料,通过溶胶-凝胶法制备了可磁分离回收的CoFe_(2)O_(4)/生物炭复合材料(MPBC),通过X-射线衍射仪(XRD)、傅立叶红外光谱仪(FT-IR)、扫描电镜(SEM)、比表面积分析仪(BET)、X射线光电子能谱仪(XPS)和振动样品磁强计(VSM)对MPBC结构和表面物理化学性质进行表征和分析.利用MPBC活化过硫酸盐(PS)去除罗丹明B(RhB),并考察了MPBC的重复利用性能.结果表明,在RhB初始浓度为40mg/L,溶液初始pH值为5,温度为25℃,MPBC投加量为8.0g/L,PS浓度为0.05mol/L时,RhB去除率在120min达到98.8%.其去除率随MPBC投加量和初始RhB浓度的增加而提高,并在较宽的pH值范围内(3~11)具有有效性.腐殖酸、NO_(3)-、HCO_(3)-和Cl^(-)对RhB去除效率有一定的抑制作用.自由基淬灭实验与电子顺磁共振(EPR)测试结果表明,MPBC-PS体系中的活性物质主要包括SO_(4)^(·-)、·OH、m^(1)O_(2)和·O_(2)^(-).VSM测得MPBC的饱和磁化强度为23.41emu/g,表明其易于磁回收.MPBC经过5次循环利用后,RhB去除率仍可达到95.4%,表现了良好的稳定性.
The magnetic CoFe_(2)O_(4)/biochar(MPBC)derived from pine needles was prepared by a sol-gel method.The structure and surface physical-chemical properties of as-prepared MPBC was characterized by X-ray diffraction(XRD),Fourier transform infrared spectrometer(FT-IR),scanning electron microscopy(SEM),specific surface area analyzer(BET),X-ray photoelectron spectrometer(XPS)and vibrating sample magnetometer(VSM).The MPBC was used to activate peroxynitrite(PS)for Rhodamine B(RhB)removal.The results showed that under the optimal conditions of initial RhB concentration of 40mg/L,initial pH value of 5,temperature of 25℃,MPBC dosage of 8.0g/L and PS dosage of 0.05mol/L,the removal rate of RhB reached 98.8%after 120min.The removal rate of RhB tended to increase with the increasing of MPBC dosage and initial RhB concentration,and was effective in a wide range of pH value from 3 to 11.Humic acid,NO_(3)-,HCO_(3)-and Cl^(-)inhibited the removal efficiency of RhB.Free radical quenching experiments and electron paramagnetic resonance(EPR)tests exhibited that the active species including SO_(4)^(·-),·OH,m^(1)O_(2) and·O_(2)^(-)played a dominating role in the MPBC-PS system.The saturation magnetization intensity of MPBC measured by VSM was 23.41 emu/g,indicating that it was easy to be magnetically recovered.After 5 cycles of reuse,the RhB removal rate still reached 95.4%,showing good stability.
作者
相里鹏
崔佳丽
张峰
李红艳
崔建国
韦柳益
XIANGLI Peng;CUI Jia-li;ZHANG Feng;LI Hong-yan;CUI Jian-guo;WEI Liu-yi(Municipal Engineering Graduate Education Innovation Center of Shanxi Province,College of Environmental Science and Engineering,Taiyuan University of Technology,Taiyuan 030024,China)
出处
《中国环境科学》
EI
CAS
CSCD
北大核心
2023年第4期1672-1687,共16页
China Environmental Science
基金
山西省自然科学基金资助项目(20210302124083)。
