Dark formation of hydroxyl radical upon oxidation of reduced iron minerals plays an important role in the degradation and transformation of organic and inorganic pollutants.Herein,we compared the hydroxyl radical form...Dark formation of hydroxyl radical upon oxidation of reduced iron minerals plays an important role in the degradation and transformation of organic and inorganic pollutants.Herein,we compared the hydroxyl radical formation from various reduced iron minerals at different redox conditions.·OH production was generally observed from the oxidation of reduced iron minerals,following the order:mackinawite(FeS)>reduced nontronite(iron-bearing smectite clay)> pyrite(FeS2)> side rite(FeCO3).Structural Fe^2+ and dissolved O2 play critical roles in ·OH production from reduced iron minerals.·OH production increases with decreasing pH,and Cl^-has little effect on this process.More importantly,dissolved organic matter significantly enhances ·OH production,especially under O2 purging,highlighting the importance of this process in ambient environments.This sunlight-independent pathway in which ’OH forms during oxidation of reduced iron minerals is helpful for understanding the degradation and transformation of various inorganic and organic pollutants in the redox-fluctuation environments.展开更多
In this study,natural mackinawite (Fe S),a chalcophilic mineral,was utilized to prepare iron/copper bimetallic oxides (Cu^(O)@Fe_(x)O_(y)) by displacement plating and calcination process.Various characterization metho...In this study,natural mackinawite (Fe S),a chalcophilic mineral,was utilized to prepare iron/copper bimetallic oxides (Cu^(O)@Fe_(x)O_(y)) by displacement plating and calcination process.Various characterization methods prove that Cu;is successfully coated on the surface of Fe S,which were further oxidized to Cu^(O),Fe_(3)O_(4)and/or Fe_(2)O_(3)during calcination process,respectively.Cu^(O)@Fe_(x)O_(y)performed highly efficient capacity to activate PMS for the degradation of various emerging pollutants including sulfamethoxazole(SMX),carbamazepine (CBZ),bisphenol A (BPA),2,4-dichlorophenol (2,4-DCP) and diclofenac (DCF) in aqueous solution.Complete removal of the above pollutants was observed after 8 min of Cu^(O)@Fe_(x)O_(y)/PMS treatment.Taking SMX as an example,the key parameters including Cu^(O)@Fe_(x)O_(y)dosage,PMS dosage and initial p H were optimized.The results show that the catalytic system can be worked in a wide p H range (3.0-9.0).The quenching experiments and electron spin resonance (ESR) test demonstrated that the main reactive oxygen species in Cu^(O)@Fe_(x)O_(y)/PMS system were hydroxyl radicals (^(·)OH) and sulfate radicals(SO_(4)^(·ˉ)),and SO_(4)^(·ˉ)was the primary reactive species.Besides,the influence of coexisting anions (i.e.,Cl^(ˉ),NO_(3)^(ˉ),HCO_(3)^(ˉ)and H_(2)PO_(4)^(ˉ)) for the degradation of SMX was explored.Cu^(O)@Fe_(x)O_(y)/PMS system can maintain good catalytic activity and reusability in different water bodies and long-term running.This work provided a green strategy to fabricate the efficient catalyst in PMS-based advanced oxidation processes.展开更多
Fenton reaction is one of most promising approaches for efficient removal of various robust organic pollutants in wastewater,however it faces several intrinsic challenges such as acidic condition,sludge waste and sens...Fenton reaction is one of most promising approaches for efficient removal of various robust organic pollutants in wastewater,however it faces several intrinsic challenges such as acidic condition,sludge waste and sensitive to sulfide-containing compound.Here we reported a novel FeS1.92 as an efficient and sulfide resistant heterogeneous Fenton catalyst under mild condition.This novel FeS1.92 was facilely prepared through a mechanochemical synthesis of mackinawite(FeS) with sulfur powder(S) by ball milling.The sulfured mackinawite(FeS1.92) exhibits high performance in activating H2 O2 to generate hydroxyle radicals for organic waste remediation.Furthermore,this FeS1.92 based heterogeneous Fenton catalyst is highly sulfide resistant and shows improved performance for degrading sulfide-containing organic pollutants.This study provides an effective mechanochemical approach to fabricate heterogeneous Fenton catalysts for sulfide-containing wastewater treatment.展开更多
基金financially supported by the National Natural Science Foundation of China (No.21777178)Key Projects for Frontier Sciences of the Chinese Academy of Sciences (No.QYZDBSSWDQC018)+2 种基金the CAS Interdisciplinary Innovation Team (No. JCTD-2018-04)supports from the National Young Top-Notch Talents (No.W03070030)Youth Innovation Promotion Association of the Chinese Academy of Sciences (No. 2016037)
文摘Dark formation of hydroxyl radical upon oxidation of reduced iron minerals plays an important role in the degradation and transformation of organic and inorganic pollutants.Herein,we compared the hydroxyl radical formation from various reduced iron minerals at different redox conditions.·OH production was generally observed from the oxidation of reduced iron minerals,following the order:mackinawite(FeS)>reduced nontronite(iron-bearing smectite clay)> pyrite(FeS2)> side rite(FeCO3).Structural Fe^2+ and dissolved O2 play critical roles in ·OH production from reduced iron minerals.·OH production increases with decreasing pH,and Cl^-has little effect on this process.More importantly,dissolved organic matter significantly enhances ·OH production,especially under O2 purging,highlighting the importance of this process in ambient environments.This sunlight-independent pathway in which ’OH forms during oxidation of reduced iron minerals is helpful for understanding the degradation and transformation of various inorganic and organic pollutants in the redox-fluctuation environments.
基金financial support from National Natural Science Foundation of China (No.51878423)China Postdoctoral Science Foundation (No.2019T120843)Sichuan Science and Technology Program (No.2019YJ0091)。
文摘In this study,natural mackinawite (Fe S),a chalcophilic mineral,was utilized to prepare iron/copper bimetallic oxides (Cu^(O)@Fe_(x)O_(y)) by displacement plating and calcination process.Various characterization methods prove that Cu;is successfully coated on the surface of Fe S,which were further oxidized to Cu^(O),Fe_(3)O_(4)and/or Fe_(2)O_(3)during calcination process,respectively.Cu^(O)@Fe_(x)O_(y)performed highly efficient capacity to activate PMS for the degradation of various emerging pollutants including sulfamethoxazole(SMX),carbamazepine (CBZ),bisphenol A (BPA),2,4-dichlorophenol (2,4-DCP) and diclofenac (DCF) in aqueous solution.Complete removal of the above pollutants was observed after 8 min of Cu^(O)@Fe_(x)O_(y)/PMS treatment.Taking SMX as an example,the key parameters including Cu^(O)@Fe_(x)O_(y)dosage,PMS dosage and initial p H were optimized.The results show that the catalytic system can be worked in a wide p H range (3.0-9.0).The quenching experiments and electron spin resonance (ESR) test demonstrated that the main reactive oxygen species in Cu^(O)@Fe_(x)O_(y)/PMS system were hydroxyl radicals (^(·)OH) and sulfate radicals(SO_(4)^(·ˉ)),and SO_(4)^(·ˉ)was the primary reactive species.Besides,the influence of coexisting anions (i.e.,Cl^(ˉ),NO_(3)^(ˉ),HCO_(3)^(ˉ)and H_(2)PO_(4)^(ˉ)) for the degradation of SMX was explored.Cu^(O)@Fe_(x)O_(y)/PMS system can maintain good catalytic activity and reusability in different water bodies and long-term running.This work provided a green strategy to fabricate the efficient catalyst in PMS-based advanced oxidation processes.
基金the National Natural Science Foundation of China (No.21777097)Shanghai Shuguang Grant(No.17SG11)the China Postdoctoral Science Foundation (Nos.2017M621483,2018T110397)。
文摘Fenton reaction is one of most promising approaches for efficient removal of various robust organic pollutants in wastewater,however it faces several intrinsic challenges such as acidic condition,sludge waste and sensitive to sulfide-containing compound.Here we reported a novel FeS1.92 as an efficient and sulfide resistant heterogeneous Fenton catalyst under mild condition.This novel FeS1.92 was facilely prepared through a mechanochemical synthesis of mackinawite(FeS) with sulfur powder(S) by ball milling.The sulfured mackinawite(FeS1.92) exhibits high performance in activating H2 O2 to generate hydroxyle radicals for organic waste remediation.Furthermore,this FeS1.92 based heterogeneous Fenton catalyst is highly sulfide resistant and shows improved performance for degrading sulfide-containing organic pollutants.This study provides an effective mechanochemical approach to fabricate heterogeneous Fenton catalysts for sulfide-containing wastewater treatment.
