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Copyright of Industrial Water Treatment is the property of CNOOC Tianjin Chemical Research & Design Institute and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of China Forest Products Industry is the property of China Forest Products Industry Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Aiming at the environmental pollution problems caused by vanadium-containing wastewater produced by mining, metallurgy, petroleum refining, and other industries, this study prepared mussel shells loaded nano-zero-valent iron composites(nZVI@CMS) by liquid-phase reduction method using pyrolyzed mussel shell powder(CMS) as the carrier. The morphology and structure of nZVI@CMS were characterized by SEM, TEM, XRD, BET, FT-IR and XPS. The adsorption performance of V(Ⅴ) on nZVI@CMS was investigated by batch adsorption experiments, and the adsorption mechanism of V(Ⅴ) on nZVI@CMS was analyzed using adsorption kinetics, adsorption isotherm, and adsorption thermodynamics. The results showed that nZVI@CMS was a loose and porous chain sphere-like structure containing a variety of oxygen-containing functional groups. The maximum adsorption of V(Ⅴ) by nZVI@CMS was 149.33 mg/g under the conditions of nZVI@CMS dosage of 0.05 g/L, initial pH=7, V(Ⅴ) concentration of 20 mg/L, solution volume of 100 mL, and temperature of 25 ℃. The adsorption of V(Ⅴ) by nZVI@CMS could be fitted by Langmuir adsorption isotherm equation and pseudo second-order reaction kinetic equation, and it was a spontaneous heat adsorption process. The main mechanisms of V(Ⅴ) removal by nZVI@CMS included adsorption, reduction, and co-precipitation. This study turned the mussel shells into treasure, and provided a new idea for the efficient treatment of V(Ⅴ) in wastewater.

Copyright of Journal of Zhejiang University (Science Edition) is the property of Journal of Zhejiang University (Science Edition) Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Agro-Environment Science is the property of Journal of Agro-Environment Science Editorial Board and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Nanoscale zero-valent iron（nZVI） is a kind of widely-concerned environmental remediation material，which expands the application scope of iron-based materials in site remediation and pollutant removal because it has both the reactive activity of nanoscale materials and the reductive property of zero-valent iron. Although nZVI is more effective，the more complex preparation process leads to increased environmental footprint and production costs，the preparation method of nZVI is becoming a key constraint to its development. The paper introduced the development of nZVI and carded the various preparation methods and characteristics of nZVI from the perspective of sustainable development. Furthermore，this paper examined the potential environmental consequences resulting from the preparation process of nZVI. On this basis，the sustainability of typical nZVI preparation was assessed，and potential unsustainable factors were quantified，highlighting the dependence of the preparation process on electrical energy sources. Based on the existing researching，the large-scale and potential methods of preparation of nZVI were prospected，such as laser ablation. Moreover，it illustrated the importance of choosing reasonable preparation method，emphasizing the indispensable position of the sustainability assessment of nZVI in the future development. It is hoped to provide a reference for researchers and policy makers in the selection and improvement of nZVI preparation methods.

Nano zero-valent iron (nZVI) has problems such as agglomeration, passivation and poor transportability, which affect the in situ remediation effect of Cr(VI) contaminated groundwater. To develop a low-cost, green nZVI modified material, a low-cost, green modification for nZVI was developed. The nZVI@BC reaction system was constructed by supporting nZVI with ball-milled biochar (BC) as carrier and then stabilized with carboxymethyl cellulose (CMC). CMC-nZVI@BC was synthesized as a novel high-efficiency, anti-passivation nano-scale remediation material. The nZVI before and after modification was characterized and analyzed, and the effects of CMC-nZVI@BC addition, initial concentration of Cr(VI), pH and temperature and chemical fraction of groundwater on the removal of Cr(VI) by CMC-nZVI@BC were investigated, and the mechanism of Cr(VI) removal by CMC-nZVI@BC was elucidated, and the following conclusions were obtained: (1) The best removal of Cr(VI) by nZVI@BC at the Fe and C mass ratio of 2∶1； the removal rate of 50 mg/L Cr(VI) by 0.6 g/L CMC-nZVI@BC within 3 h reached 99.9%, exhibiting a high removal rate and capacity of Cr(VI). (2) The main mechanism of Cr(VI) removal by CMC-nZVI@BC was reduction and precipitation. (3) In the range of 2 to 10, the pH value had a significant effect on the removal of Cr(VI) by CMC-nZVI@BC, with less effect of temperature. (4) The presence of \begin{document}${\mathrm{SO}}_4^{2-} $\end{document} promoted Cr(VI) removal, while \begin{document}${\mathrm{HCO}}_3^{-} $\end{document}, \begin{document}${\mathrm{NO}}_3^{-} $\end{document}, Ca2+, Mg2+ and humic acid, all had different degrees of inhibition on Cr(VI) removal. These results suggest that CMC-nZVI@BC can be an effective in situ remediation agent for Cr(VI) removal, offering the possibility of applying nZVI for in situ groundwater remediation.

Copyright of Hydrogeology & Engineering Geology / Shuiwendizhi Gongchengdizhi is the property of Hydrogeology & Engineering Geology Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Industrial Water Treatment is the property of CNOOC Tianjin Chemical Research & Design Institute and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Biochars loaded by nano zero-valent iron were environmentally friendly prepared using leaves of sycamore tree as raw materials and green tea filtrate as the reductant. The adsorption and removal of Cr (VI) on the prepared biochar samples was investigated in details for remediation of hexavalent chromium pollution in industrial wastewater. Modern instrumental analysis technologies were used to characterize the physical and chemical properties of the materials, such as micro morphology, functional groups, element composition and so on. Different Fe/C loading ratio, material dosage and initial Cr(VI) concentration were analyzed and compared to screen out the best preparation and adsorption conditions for the removal of Cr(VI). The results show that nano zero-valent iron particles are uniformly attached to the smooth and stretched surface of biochars, and the materials contain a variety of organic matters including phenols, olefins, aromatic compounds and alcohols. After loading nano zero-valent iron, the graphite structure of biochars remain the same, and the characteristic peaks of zero-valent iron can be found in XRD spectrum. The optimum preparation conditions are the pyrolysis temperature of 600 °C and the Fe/C loading ratio of 1: 24. Biochar loaded with nano zero-valent iron material (2.0 g) is added to 50 mL of Cr(VI) solution (10 mg/L), the maximum removal rate of Cr(VI) is 58.72% after the adsorption for 60 minutes. [ABSTRACT FROM AUTHOR]

Copyright of Environmental Science & Technology (10036504) is the property of Editorial Board of Environmental Science & Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Agro-Environment Science is the property of Journal of Agro-Environment Science Editorial Board and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Hydrometallurgy of China is the property of Hydrometallurgy of China Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Aiming at the potential hazard of the wastewater with the coexistence of selenium and antibiotics in selenium-enriched aquaculture, nano zero-valent iron (nZVI) was in situ synthesized on the N-doped porous biochar (NBC) prepared by shrimp shells, resulting in the composites (NBC-nZVI) with active functional components of NBC and nZVI. The samples were characterized by scanning electron microscopy (SEM), nitrogen adsorption, X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR) and X-ray photoelectron spectroscopy (XPS). Taking Se (IV) and ciprofloxacin (CIP) as the targeted pollutants, the simultaneous adsorption behavior of NBC-nZVI was investigated. The results showed that the removal performance of NBC-nZVI toward CIP and Se( IV) was superior to that of NBC and nZVI. Se (IV) was preferentially adsorbed on the surface of NBC-nZVI compared to CIP, which mediated the adsorption of CIP and improved the removal performance of NBC-nZVI to CIP. The adsorption of NBC-nZVI for Se(IV) was nearly immune to CIP. The adsorption behavior of NBC-nZVI toward CIP and Se( IV) in the bicomponent system followed the pseudo-second-order kinetics and Sips isotherm model, and the theo-retical maximum adsorption capacities for CIP and Se(IV) were 130.6,335.7 mg/g, respectively. [ABSTRACT FROM AUTHOR]

Copyright of Research of Environmental Sciences is the property of Research of Environmental Sciences Editorial Board and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

With suspension polymerized chloromethylated polystyrene microspheres as carrier, NZVI—PS was prepared by the sodium borohydride reduction method in liquid phase. The prepared NZVI—PS was characterized by SEM, EDS and BET and used to degrade the high toxic and hard-degraded substance of nitrobenzene (NB). The experiments were conducted to discuss the effects of microsphere dosage, solution temperature and pH on the degradation of different initial concentration nitrobenzene. The adsorber-reduction dynamics mechanism of NZVI—PS to nitrobenzene and the reuse performance of microspheres were also discussed. The results show that the nanoscale zero-valent iron in NZVI—PS has good dispersion performance with large specific surface area, and the agglomeration is not obvious. After being used repeatedly for four times, the using value of the carrier microspheres is still very high. The nitrobenzene degradation rate can reach 99.8％ under the optimal conditions, and the adsorber-reduction reaction rate is in line with the first order reaction. [ABSTRACT FROM AUTHOR]

To restrain the nano zero-valent iron (NZVI) in aqueous solution from being reunited and oxidized, this paper used sodium carboxymethyl starch (CMS), which is an environmentally friendly and cheap material, for coating and surface modification of NZVI so as to improve its dispersity and suspension property. Transmission Electron Microscope (TEM) and X-ray diffraction (XRD) were used to study the microstructure and components of the modified NZVI, and the 2,4-dichlorophenol 2,4-(DCP) removal efficiency was researched through chemical experiment. Experiments showed that the modified NZVI was about 80~100 nm in diameter, present as chain or dispersed particles. The main component was zero-valent iron, and it had strong reducibility. When the proportion of CMS was 80.00%, the suspension property was the best; The NZVI after CMS coating and surface modification retained the original activity. In the experiment investigating the removal effect of 2,4-DCP using different proportion of cladding, the same finding was obtained. When the CMS's proportion was 80%, the removal effect was the best, reaching up to 83.69%, and the dechlorination and degradation were apparent.