Two coordination polymers were synthesized by hydrothermal reaction,namely,[Cd(H_(3)cpbda)(2,2′‑bipy)(H_(2)O)]_(n)(1)and[Mn(H_(3)cpbda)(phen)(H_(2)O)]_(n)(2),where H_(5)cpbda=5,5′‑[(5‑carboxy‑1,3‑phenyl)bis(oxy)]triisophthalic acid,2,2′‑bipy=2,2′‑bipyridine,phen=1,10‑phenanthroline.The two complexes were characterized by single‑crystal X‑ray diffraction,powder diffraction,infrared spectroscopy,and thermogravimetric analysis.Complexes 1 and 2 are“V”‑shaped 1D chains,and the molecules form 2D(1)and 3D framework(2)structures through weakπ…πstacking.Furthermore,complex 1 was dispersed in an aqueous solution and its fluorescence intensity demonstrated excellent stability.Complex 1 can specifically detect ciprofloxacin in urine with a detection limit of 1.91×10^(-8)mol·L^(-1).CCDC:2359498,1;2359499,2.
YANG DongdongXUE JianhuaYANG YuanyuWU MeixiaBAI YujiaWANG ZongxuanMA Qi
Sulfide oxidation under aerobic conditions can produce active oxygen for the transformation of organic pollutants in aquatic environments.However,the catalytic performance of transition metal-supported carbon material on this process is poor understood.This study found that Co-loaded carbon nanotubes(CNTs)was able to realize the efficient aerobic transformation of antibiotic ciprofloxacin(CIP)by sulfide,with the pseudo-first order reaction rate constant improved from 0.013 h^(-1)without catalyst to 0.44–0.71 h^(-1)with 100 mg/L Co-loaded CNTs.Singlet oxygen(^(1)O_(2))was the main active specie playing key roles in the process of CIP aerobic transformation with presence of Co-loaded CNTs.Mechanism studies indicated that the excellent electron transfer ability of Co-loaded CNTs might play an important role to promote the electron transfer and facilitate the formation of intermediate H_(2)O_(2)and^(1)O_(2).Additionally,the Co-loaded CNTs/sulfide system effectively reduced the acute toxicity of organic pollutant,and Co-loaded CNTs showed remarkable cycling stability and negligible leaching.This study gives a better understanding for the Co-loaded CNTs mediated aerobic antibiotics transformation by sulfide,and provide a reference for the application of Co-loaded carbon materials on organics aerobic transformation by sulfide.
Han-Qing ZhaoPeili LuFei ChenChen-Xuan LiRui YanYang Mu
In this study,a stepwise oxidation system of potassium ferrate(K_(2)FeO_(4))combined with ozone(O+3)was used to degrade ciprofloxacin(CIP).The effects of pH and pre-oxidation time of K_(2)FeO_(4) on the evolution of K_(2)FeO_(4) reduction products(iron(hydr)oxides)and CIP degradation were investigated.It was found that in addition to its own oxidation capacity,K_(2)FeO_(4) can also influence the treatment effect of CIP by changing the catalyst content.The presence of iron(hydr)oxides effectively enhanced the mineralization rate of CIP by catalyzing ozonation.The pH value can influence the content and types of the components with catalytic ozonation effect in iron(hydr)oxides.The K_(2)FeO_(4) pre-oxidation stage can produce more iron(hydr)oxides with catalytic components for subsequent ozonation,but the evolution of iron(hydr)oxides components was influenced by O_(3) treatment.It can also avoid the waste of oxidation capacity owing to the oxidation of iron(hydr)oxides by O_(3) and free radicals.The intermediate degradation products were identified by Fourier transform ion cyclotron resonance mass spectrometry(FT-ICR-MS).Besides,the degradation pathways were proposed.Among the degradation products of CIP,the product with broken quinolone ring structure only appeared in the stepwise oxidation system.
Xiaochen LiYifan WangNing WangMei LiMaomao BaiJingtao XuHongbo Wang
Ciprofloxacin(CIP)is a commonly used antibiotic in the fluoroquinolone group and is widely used in medical and veterinary medicine disciplines to treat bacterial infections.When CIP is discharged into the sewage system,it cannot be removed by a conventional wastewater treatment plant because of its recalcitrant characteristics.In this study,boron-doped diamond anode and persulfate were used to degrade CIP in an aquatic solution by creating an electrochemically activated persulfate(EAP)process.Ironwas added to the system as a coactivator and the process was called EAP+Fe.The effects of independent variables,including pH,Fe^(2+),persulfate concentration,and electrolysis time on the systemwere optimized using the response surface methodology.The results showed that the EAP+Fe process removed 94%of CIP under the following optimum conditions:A pH of 3,persulfate/Fe^(2+)concentration of 0.4 mmol/L,initial CIP concentration 30 mg/L,and electrolysis time of 12.64 min.CIP removal efficiency was increased from 65.10%to 94.35%by adding Fe^(2+)as a transition metal.CIP degradation products,7 pathways,and 78 intermediates of CIP were studied,and three of those intermediates(m/z 298,498,and 505)were reported.The toxicological analysis based on toxicity estimation software results indicated that some degradation products of CIP were toxic to targeted animals,including fathead minnow,Daphnia magna,Tetrahymena pyriformis,and rats.The optimumoperation costswere similar in EAP and EAP+Fe processes,approximately 0.54€/m^(3).
The abused ciprofloxacin antibiotics have caused significant environmental damage.Although oxidative degradation of ciprofloxacin exhibits promising efficacy,it often entails excessive energy consumption.Hence,it is necessary to explore an effective and ecologically sustainable degradation strategy.Herein,we demonstrated that g-C_(3)N_(4) decorated with the coordinated CeO_(2)and Co_(3)O_(4)(CeO_(2)-Co_(3)O_(4)/CN)exhibited effective ciprofloxacin photodegradation via in situ H_(2)O_(2) production and activation mechanism.Results indicate that the introduced CeO_(2) enhances the transference of photogenerated electrons to O_(2) by adjusting the oxygen vacancy of photocatalyst,thereby increasing the generation of superoxide radicals,which in turn generate H_(2)O_(2),resulting in a 22.4-fold increase in H_(2)O_(2) generation over g-C_(3)N_(4).Moreover,the in situ H_(2)O_(2)generation facilitated by CeO_(2) is confirmed to be essential for ciprofloxacin degradation via CeO_(2)-Co_(3)O_(4)/CN,as it provides enough oxidant for Co_(3)O_(4) to activate into hydroxyl radicals for the pollutants degradation.Ultimately,CeO_(2)-Co_(3)O_(4)/CN achieves a ciprofloxacin degradation ratio of 97.7%within 80 min.This study introduces a novel approach that combines H_(2)O_(2) generation and activation,offering an innovative perspective for achieving clean and efficient purification of antibiotic-contaminated water.
