Owing to outstanding hydrophilicity and ionic interaction,layered double hydroxides(LDHs)have emerged as a promising carrier for high performance catalysts.However,the synthesis of new specialized catalytic LDHs for d...Owing to outstanding hydrophilicity and ionic interaction,layered double hydroxides(LDHs)have emerged as a promising carrier for high performance catalysts.However,the synthesis of new specialized catalytic LDHs for degradation of antibiotics still faces some challenges.In this study,a CoFe_(2)O_(4)/MgAl-LDH composite catalyst was synthesized using a hydrothermal coprecipitation method.Comprehensive characterization reveals that the surface of MgAl-LDH is covered with nanometer CoFe_(2)O_(4) particles.The specific surface area of CoFe_(2)O_(4)/MgAl-LDH is 82.84 m^(2)·g^(-)1,which is 2.34 times that of CoFe_(2)O_(4).CoFe_(2)O_(4)/MgAl-LDH has a saturation magnetic strength of 22.24 A·m^(2)·kg^(-1) facilitating efficient solid-liquid separation.The composite catalyst was employed to activate peroxymonosulfate(PMS)for the efficient degradation of tetracycline hydrochloride(TCH).It is found that the catalytic performance of CoFe_(2)O_(4)/MgAl-LDH significantly exceeds that of CoFe_(2)O_(4).The maximum TCH removal reaches 98.2%under the optimal conditions([TCH]=25 mg/L,[PMS]=1.5 mmol/L,CoFe_(2)O_(4)/MgAl-LDH=0.20 g/L,pH 7,and T=25℃).Coexisting ions in the solution,such as SO_(4)^(2-),Cl-,H_(2)PO_(4)^(-),and CO_(3)^(2-),have a negligible effect on catalytic performance.Cyclic tests demonstrate that the catalytic performance of CoFe_(2)O_(4)/MgAl-LDH remains 67.2%after five cycles.Mechanism investigations suggest that O_(2)^(•-)and ^(1)O_(2) produced by CoFe_(2)O_(4)/MgAl-LDH play a critical role in the catalytic degradation.展开更多
开发用于高级氧化技术的廉价易得、高效稳定的催化剂对于水处理至关重要.以水滑石/壳聚糖为前驱体开发了一种新型“原位沉淀-煅烧”法制备磁性氮掺杂碳负载CoFe_(2)O_(4)-CoO催化剂(LDO/NC).该催化剂用于活化过一硫酸盐(PMS)降解四环素(...开发用于高级氧化技术的廉价易得、高效稳定的催化剂对于水处理至关重要.以水滑石/壳聚糖为前驱体开发了一种新型“原位沉淀-煅烧”法制备磁性氮掺杂碳负载CoFe_(2)O_(4)-CoO催化剂(LDO/NC).该催化剂用于活化过一硫酸盐(PMS)降解四环素(TC),表现出明显优于单纯水滑石氧化物(LDO)和氮掺杂碳(NC)的催化活性.这是由于壳聚糖作为碳源和氮源的原位引入成功抑制了钴铁金属氧化物团聚,同时N原子的掺杂增强电子转移,协同催化提高活性.研究了催化剂组成、催化剂用量、PMS用量和初始pH值等因素对TC降解效率的影响规律.最佳条件下(PMS用量0.4 g L^(-1),LDO/NC用量0.5 g L^(-1),pH=5),30 min内TC的降解率和总碳去除率分别达到97.8%和81.0%.该催化剂可磁性回收且循环使用五次以上,稳定性保持良好.提供了一种用于催化PMS氧化处理制药废水的绿色催化剂.展开更多
采用超声辅助室温原位沉淀法合成BC/Bi_(4)O_(5)Br_(2)光催化剂,在可见光下对比了TiO_(2)体系、BC/Bi_(4)O_(5)Br_(2)体系以及BC/Bi_(4)O_(5)Br_(2)耦合过一硫酸盐(PMS)体系处理渗滤液尾水的效果。考察了BC/Bi_(4)O_(5)Br_(2)耦合PMS体...采用超声辅助室温原位沉淀法合成BC/Bi_(4)O_(5)Br_(2)光催化剂,在可见光下对比了TiO_(2)体系、BC/Bi_(4)O_(5)Br_(2)体系以及BC/Bi_(4)O_(5)Br_(2)耦合过一硫酸盐(PMS)体系处理渗滤液尾水的效果。考察了BC/Bi_(4)O_(5)Br_(2)耦合PMS体系中PMS投加量和反应时间的影响,通过紫外可见光谱、三维荧光图谱分析渗滤液尾水有机物成分。结果表明:BC/Bi_(4)O_(5)Br_(2)耦合PMS体系对腐殖质的去除效果较另外两体系的效果优异,BC/Bi_(4)O_(5)Br_(2)对COD、腐殖质(A_(254))、色度(CN)的去除率分别为13.07%、12.74%、52.19%,BOD_(5)/COD从0.08提升至0.18。BC/Bi_(4)O_(5)Br_(2)耦合PMS体系中,0.1 g BC/Bi_(4)O_(5)Br_(2)耦合0.20 g PMS体系对渗滤液尾水有机物有良好的降解效果,尤其在反应开始的前0.5 h作用效果明显,1.5 h后降解效率不再明显增加。BC/Bi_(4)O_(5)Br_(2)耦合PMS体系对TOC的最大去除率为30.5%,较BC/Bi_(4)O_(5)Br_(2)体系提高16.5%;对腐殖质的最大去除率为53.97%,较BC/Bi_(4)O_(5)Br_(2)体系提升41.5%。紫外可见光谱、三维荧光图谱表明渗滤液尾水以类腐殖质为主。研究结果可为非均相耦合过一硫酸盐光催化处理渗滤液尾水提供一定参考。展开更多
基金University Synergy Innovation Program of Anhui Province(GXXT-2022-083)Science and Technology Plan Project of Wuhu City,China(2023kx12)Anhui Provincial Department of Education New Era Education Project(2023xscx070)。
文摘Owing to outstanding hydrophilicity and ionic interaction,layered double hydroxides(LDHs)have emerged as a promising carrier for high performance catalysts.However,the synthesis of new specialized catalytic LDHs for degradation of antibiotics still faces some challenges.In this study,a CoFe_(2)O_(4)/MgAl-LDH composite catalyst was synthesized using a hydrothermal coprecipitation method.Comprehensive characterization reveals that the surface of MgAl-LDH is covered with nanometer CoFe_(2)O_(4) particles.The specific surface area of CoFe_(2)O_(4)/MgAl-LDH is 82.84 m^(2)·g^(-)1,which is 2.34 times that of CoFe_(2)O_(4).CoFe_(2)O_(4)/MgAl-LDH has a saturation magnetic strength of 22.24 A·m^(2)·kg^(-1) facilitating efficient solid-liquid separation.The composite catalyst was employed to activate peroxymonosulfate(PMS)for the efficient degradation of tetracycline hydrochloride(TCH).It is found that the catalytic performance of CoFe_(2)O_(4)/MgAl-LDH significantly exceeds that of CoFe_(2)O_(4).The maximum TCH removal reaches 98.2%under the optimal conditions([TCH]=25 mg/L,[PMS]=1.5 mmol/L,CoFe_(2)O_(4)/MgAl-LDH=0.20 g/L,pH 7,and T=25℃).Coexisting ions in the solution,such as SO_(4)^(2-),Cl-,H_(2)PO_(4)^(-),and CO_(3)^(2-),have a negligible effect on catalytic performance.Cyclic tests demonstrate that the catalytic performance of CoFe_(2)O_(4)/MgAl-LDH remains 67.2%after five cycles.Mechanism investigations suggest that O_(2)^(•-)and ^(1)O_(2) produced by CoFe_(2)O_(4)/MgAl-LDH play a critical role in the catalytic degradation.
文摘开发用于高级氧化技术的廉价易得、高效稳定的催化剂对于水处理至关重要.以水滑石/壳聚糖为前驱体开发了一种新型“原位沉淀-煅烧”法制备磁性氮掺杂碳负载CoFe_(2)O_(4)-CoO催化剂(LDO/NC).该催化剂用于活化过一硫酸盐(PMS)降解四环素(TC),表现出明显优于单纯水滑石氧化物(LDO)和氮掺杂碳(NC)的催化活性.这是由于壳聚糖作为碳源和氮源的原位引入成功抑制了钴铁金属氧化物团聚,同时N原子的掺杂增强电子转移,协同催化提高活性.研究了催化剂组成、催化剂用量、PMS用量和初始pH值等因素对TC降解效率的影响规律.最佳条件下(PMS用量0.4 g L^(-1),LDO/NC用量0.5 g L^(-1),pH=5),30 min内TC的降解率和总碳去除率分别达到97.8%和81.0%.该催化剂可磁性回收且循环使用五次以上,稳定性保持良好.提供了一种用于催化PMS氧化处理制药废水的绿色催化剂.
文摘采用超声辅助室温原位沉淀法合成BC/Bi_(4)O_(5)Br_(2)光催化剂,在可见光下对比了TiO_(2)体系、BC/Bi_(4)O_(5)Br_(2)体系以及BC/Bi_(4)O_(5)Br_(2)耦合过一硫酸盐(PMS)体系处理渗滤液尾水的效果。考察了BC/Bi_(4)O_(5)Br_(2)耦合PMS体系中PMS投加量和反应时间的影响,通过紫外可见光谱、三维荧光图谱分析渗滤液尾水有机物成分。结果表明:BC/Bi_(4)O_(5)Br_(2)耦合PMS体系对腐殖质的去除效果较另外两体系的效果优异,BC/Bi_(4)O_(5)Br_(2)对COD、腐殖质(A_(254))、色度(CN)的去除率分别为13.07%、12.74%、52.19%,BOD_(5)/COD从0.08提升至0.18。BC/Bi_(4)O_(5)Br_(2)耦合PMS体系中,0.1 g BC/Bi_(4)O_(5)Br_(2)耦合0.20 g PMS体系对渗滤液尾水有机物有良好的降解效果,尤其在反应开始的前0.5 h作用效果明显,1.5 h后降解效率不再明显增加。BC/Bi_(4)O_(5)Br_(2)耦合PMS体系对TOC的最大去除率为30.5%,较BC/Bi_(4)O_(5)Br_(2)体系提高16.5%;对腐殖质的最大去除率为53.97%,较BC/Bi_(4)O_(5)Br_(2)体系提升41.5%。紫外可见光谱、三维荧光图谱表明渗滤液尾水以类腐殖质为主。研究结果可为非均相耦合过一硫酸盐光催化处理渗滤液尾水提供一定参考。
