The intensification of estrogen non-point source pollution has drawn global attention due to their contribution to ecological environment problems worldwide,and it is critical to develop effective,economic and eco-fri...The intensification of estrogen non-point source pollution has drawn global attention due to their contribution to ecological environment problems worldwide,and it is critical to develop effective,economic and eco-friendly methods for reducing estrogens pollution.To address the agglomeration and oxidation of nano zero-valent iron(nZVI),biochar-nanoscale zero-valent iron composite(nZVI-biochar)could be a feasible choice for estrogens removal.This study summarized biochar and nZVI-biochar preparation,characterization,and unusual applications for estrone(E1),17β-estradiol(E2),and estriol(E3)removal.The properties of biochar and nZVI-biochar in characterization,effects of influencing factors on the removal efficiency,adsorption kinetics,isotherm and thermodynamics were investigated.The experiment results showed that nZVI-biochar exhibited the superior removal performance for estrogens pollutants compared to biochar.Based on the quasi-second-order model,estrogens adsorption kinetics were observed,which supported the mechanism that chemical and physical adsorption existed simultaneously on estrogens removal.The adsorption isotherm of estrogens could be well presented by the Freundlich model and thermodynamics studies explained that nZVI-biochar could spontaneously remove estrogens pollutants and the main mechanisms involvedπ-πinteraction,hydrophobic interaction,hydrogen bonding and degradation through ring rupture.The products analyzed by GC-MS showed that estrogens degradation was primarily attributed to the benzene ring broken,and Fe^(3+)promoted the production of free radicals,which further proved that nZVI-biochar had the excellent adsorption performances.Generally,nZVI-biochar could be employed as a potential material for removing estrogens from wastewater.展开更多
An organo-montmorillonite-supported nanoscale zero-valent iron material （M-NZVI） was synthesized to degrade decabromodiphenyl ether （BDE-209）. The results showed that nanoscale zero-valent iron had good dispersion...An organo-montmorillonite-supported nanoscale zero-valent iron material （M-NZVI） was synthesized to degrade decabromodiphenyl ether （BDE-209）. The results showed that nanoscale zero-valent iron had good dispersion on organo-montmoriUonite and was present as a core-shell structure with a particle size range of nanoscale iron between 30-90 nm, characterized by XRD, SEM, TEM, XRF, ICP-AES, and XPS. The results of the degradation of BDE-209 by M-NZVI showed that the efficiency of M-NZVI in removing BDE-209 was much higher than that of NZVI. The efficiency of M-NZVI in removing BDE-209 decreased as the pH and the initial dissolved oxygen content of the reaction solution increased, but increased as the proportion of water in the reaction solution increased.展开更多
Nanoscale zero-valent iron(n ZVI) particles supported on a porous, semi-interpenetrating(semi-IPN), temperature-sensitive composite hydrogel(PNIPAm-PHEMA). n ZVI@PNIPAmPHEMA, was successfully synthesized and character...Nanoscale zero-valent iron(n ZVI) particles supported on a porous, semi-interpenetrating(semi-IPN), temperature-sensitive composite hydrogel(PNIPAm-PHEMA). n ZVI@PNIPAmPHEMA, was successfully synthesized and characterized by FT-IR, SEM, EDS, XRD and the weighing method. The loading of nZVI was 0.1548 ± 0.0015 g/g and the particle size was30–100 nm. NZVI was uniformly dispersed on the pore walls inside the PNIPAm-PHEMA.Because of the well-dispersed n ZVI, the highly porous structure, and the synergistic effect of PNIPAm-PHEMA, nZVI@PNIPAm-PHEMA showed excellent reductive activity and wide p H applicability. 95% of 4-NP in 100 m L of 400 mg/L 4-NP solution with initial p H 3.0–9.0 could be completely reduced into 4-AP by about 0.0548 g of fresh supported n ZVI at 18–25 °C under stirring(110 r/min) within 45 min reaction time. A greater than 99% 4-NP degradation ratio was obtained when the initial p H was 5.0–9.0. The reduction of 4-NP by nZVI@PNIPAm-PHEMA was in agreement with the pseudo-first-order kinetics model with Kobsvalues of 0.0885–0.101 min-1.NZVI@PNIPAm-PHEMA was able to be recycled, and about 85% degradation ratio of 4-NP was obtained after its sixth reuse cycle. According to the temperature sensitivity of PNIPAmPHEMA, n ZVI@PNIPAm-PHEMA exhibited very good storage stability, and about 88.9%degradation ratio of 4-NP was obtained after its storage for 30 days. The hybrid reducer was highly efficient for the reduction of 2-NP, 3-NP, 2-chloro-4-nitrophenol and 2-chloro-4-nitrophenol. Our results suggest that PNIPAm-PHEMA could be a good potential carrier, with n ZVI@PNIPAm-PHEMA having potential value in the application of reductive degradation of nitrophenol pollutants.展开更多
用具有良好吸附能力的羟基铝柱撑膨润土作载体,通过FeSO4与NaBH4反应制得羟基铝柱撑膨润土负载的纳米铁(nanoscale zero-valent iron supported on Al-pillared bentonite,NZVI/Al-PILC).用X射线衍射(X-ray diffraction,XRD)(、Brunauer...用具有良好吸附能力的羟基铝柱撑膨润土作载体,通过FeSO4与NaBH4反应制得羟基铝柱撑膨润土负载的纳米铁(nanoscale zero-valent iron supported on Al-pillared bentonite,NZVI/Al-PILC).用X射线衍射(X-ray diffraction,XRD)(、Brunauer-Emmett-Teller,BET)法对NZVI/Al-PILC进行了结构表征.以Cr(Ⅵ)为目标污染物,考察了NZVI/Al-PILC与Cr(Ⅵ)反应过程中,介质pH、不同起始浓度的Cr(Ⅵ)对其去除率的影响,并与相同铁含量的纳米铁(nanoscale zero-valent iron,NZVI)进行了比较.结果表明,在相同实验条件下,Cr(Ⅵ)与NZVI/Al-PILC反应120 min后去除率接近100%,不仅高于相同铁含量NZVI对Cr(Ⅵ)去除率(63.0%),而且也明显优于相同铁含量的NZVI和相同含土量的羟基铝柱撑膨润土对Cr(Ⅵ)去除率的加和(75.4%).展开更多
基金Study on Colloidal Coagulation and Heavy Metal Adsorption Mechanism of Sediment River(No.42007158)Study on the distribution characteristics of birds and the reduction technology of typical pollutants in their habitats in the Yellow River basin(Henan section)(No.23B180008)supported this research.
文摘The intensification of estrogen non-point source pollution has drawn global attention due to their contribution to ecological environment problems worldwide,and it is critical to develop effective,economic and eco-friendly methods for reducing estrogens pollution.To address the agglomeration and oxidation of nano zero-valent iron(nZVI),biochar-nanoscale zero-valent iron composite(nZVI-biochar)could be a feasible choice for estrogens removal.This study summarized biochar and nZVI-biochar preparation,characterization,and unusual applications for estrone(E1),17β-estradiol(E2),and estriol(E3)removal.The properties of biochar and nZVI-biochar in characterization,effects of influencing factors on the removal efficiency,adsorption kinetics,isotherm and thermodynamics were investigated.The experiment results showed that nZVI-biochar exhibited the superior removal performance for estrogens pollutants compared to biochar.Based on the quasi-second-order model,estrogens adsorption kinetics were observed,which supported the mechanism that chemical and physical adsorption existed simultaneously on estrogens removal.The adsorption isotherm of estrogens could be well presented by the Freundlich model and thermodynamics studies explained that nZVI-biochar could spontaneously remove estrogens pollutants and the main mechanisms involvedπ-πinteraction,hydrophobic interaction,hydrogen bonding and degradation through ring rupture.The products analyzed by GC-MS showed that estrogens degradation was primarily attributed to the benzene ring broken,and Fe^(3+)promoted the production of free radicals,which further proved that nZVI-biochar had the excellent adsorption performances.Generally,nZVI-biochar could be employed as a potential material for removing estrogens from wastewater.
基金supported by the National Science and Technology Major Projects of Water Pollution Control andManagement of China (No. 2012ZX07206002)
文摘An organo-montmorillonite-supported nanoscale zero-valent iron material （M-NZVI） was synthesized to degrade decabromodiphenyl ether （BDE-209）. The results showed that nanoscale zero-valent iron had good dispersion on organo-montmoriUonite and was present as a core-shell structure with a particle size range of nanoscale iron between 30-90 nm, characterized by XRD, SEM, TEM, XRF, ICP-AES, and XPS. The results of the degradation of BDE-209 by M-NZVI showed that the efficiency of M-NZVI in removing BDE-209 was much higher than that of NZVI. The efficiency of M-NZVI in removing BDE-209 decreased as the pH and the initial dissolved oxygen content of the reaction solution increased, but increased as the proportion of water in the reaction solution increased.
基金supported by the National Natural Science Foundation of China(No.51508233)the Jiangsu Collaborative Innovation Center of Technology and Material of Water Treatment
文摘Nanoscale zero-valent iron(n ZVI) particles supported on a porous, semi-interpenetrating(semi-IPN), temperature-sensitive composite hydrogel(PNIPAm-PHEMA). n ZVI@PNIPAmPHEMA, was successfully synthesized and characterized by FT-IR, SEM, EDS, XRD and the weighing method. The loading of nZVI was 0.1548 ± 0.0015 g/g and the particle size was30–100 nm. NZVI was uniformly dispersed on the pore walls inside the PNIPAm-PHEMA.Because of the well-dispersed n ZVI, the highly porous structure, and the synergistic effect of PNIPAm-PHEMA, nZVI@PNIPAm-PHEMA showed excellent reductive activity and wide p H applicability. 95% of 4-NP in 100 m L of 400 mg/L 4-NP solution with initial p H 3.0–9.0 could be completely reduced into 4-AP by about 0.0548 g of fresh supported n ZVI at 18–25 °C under stirring(110 r/min) within 45 min reaction time. A greater than 99% 4-NP degradation ratio was obtained when the initial p H was 5.0–9.0. The reduction of 4-NP by nZVI@PNIPAm-PHEMA was in agreement with the pseudo-first-order kinetics model with Kobsvalues of 0.0885–0.101 min-1.NZVI@PNIPAm-PHEMA was able to be recycled, and about 85% degradation ratio of 4-NP was obtained after its sixth reuse cycle. According to the temperature sensitivity of PNIPAmPHEMA, n ZVI@PNIPAm-PHEMA exhibited very good storage stability, and about 88.9%degradation ratio of 4-NP was obtained after its storage for 30 days. The hybrid reducer was highly efficient for the reduction of 2-NP, 3-NP, 2-chloro-4-nitrophenol and 2-chloro-4-nitrophenol. Our results suggest that PNIPAm-PHEMA could be a good potential carrier, with n ZVI@PNIPAm-PHEMA having potential value in the application of reductive degradation of nitrophenol pollutants.
