Showing papers by "Jianxi Zhu published in 2009"
TL;DR: Fundamental results demonstrate that the montmorillonite-supported magnetite nanoparticles are readily prepared, enabling promising applications for the removal of hexavalent chromium from aqueous solution.
459 citations
TL;DR: In this paper, a series of Fe3−xTixO4 (0.78) was synthesized using a new soft chemical method using X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), Mossbauer Spectroscopy, thermogravimetric and differential scanning calorimetry (TG-DSC) analyses.
Abstract: In this work, a series of Fe3−xTixO4 (0 ≤ x ≤ 0.78) was synthesized using a new soft chemical method. The synthetic Fe3−xTixO4 were characterized using X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), Mossbauer spectroscopy, thermogravimetric and differential scanning calorimetry (TG–DSC) analyses. The results showed that they were spinel structures and Ti was introduced into their structures. Then, decolorization of methylene blue (MB) by Fe3−xTixO4 in the presence of H2O2 at neutral pH values was studied using UV–vis spectra, dissolved organic carbon (DOC) and element C analyses. Furthermore, the degradation products remained in reaction solution after the decolorization were identified using ionic chromatography (IC), 13C nuclear magnetic resonance spectra (NMR), liquid chromatography and mass spectrometry (LC–MS). Although small amounts of MB were mineralized, the aromatic rings in MB were destroyed completely after the decolorization. Decolorization of MB by Fe3−xTixO4 in the presence of H2O2 was promoted remarkably with the increase of Ti content in Fe3−xTixO4 due to the enhancement of both adsorption and degradation of MB on Fe3−xTixO4.
173 citations
TL;DR: The biological regeneration method, as an in situ, low cost and easy-operating method, is applicable for regenerating spent organoclays not only from wastewater treatment, but also from soil and groundwater remediation.
70 citations
TL;DR: Results of this work showed that IOBs prepared with proper processes could be efficient sorbents towards both HOCs and phosphate.
70 citations
TL;DR: In this article, a class of nanomaterials based upon the surface modification of layered double hydroxides (LDHs) have been synthesized by grafting silanes onto the surfaces of the LDH.
68 citations
TL;DR: The simultaneous sorption method was shown to be more effective in the sorption of 2-naphthol than the CV modified bentonite.
66 citations
TL;DR: In this article, the degradation of methylene blue (MB) on synthetic titanomagnetite at neutral pH values was studied in comparison with the adsorption of MB on titanomethane using UV−vis, FTIR, and the analyses of element C on titanomagen and DOC in reaction solution.
Abstract: In this work, titanomagnetite was used as a heterogeneous Fenton catalyst for the degradation of methylene blue (MB). The degradation of MB on synthetic titanomagnetite at neutral pH values was studied in comparison with the adsorption of MB on titanomagnetite using UV−vis, FTIR, and the analyses of element C on titanomagnetite and DOC in reaction solution. Meanwhile, important factors affecting catalytic activity were investigated, that is, titanomagnetite load, H2O2 concentration, and reaction temperature. Titanomagnetite decomposed H2O2 yielding highly reactive hydroxyl radicals, and MB adsorbed on titanomagnetite was degraded. With the increases of titanomagnetite load, H2O2 concentration, and reaction temperature, the degradation of MB was promoted. Moreover, titanomagnetite was proved to be durable with a stable MB removal efficiency after five consecutive cycles.
60 citations
TL;DR: In this article, a combination of characterizations reveals the well disperse of these obtained iron nanoparticles supported on the external surface of clay with roughly spherical morphology and mean diameter of 55 nm.
50 citations
TL;DR: The effects of surfactant concentration on the structure, morphology and thermal properties of silylated hydrotalcites have been investigated by in-situ coprecipitation.
45 citations
TL;DR: In this paper, 3-aminopropyltriethoxysilane grafted montmorillonites were synthesized with acid-activated Montmorillonite, acidactivated and acid-enhanced 3amopropyl tetroxynyl alcohol in ethanol-water mixture using Fourier transform infrared (FTIR) spectroscopy, X-ray diffraction (XRD), thermogravimetric analysis (TG).
Abstract: 3-aminopropyltriethoxysilane grafted montmorillonites were synthesized with montmorillonite, acid-activated montmorillonites and 3-aminopropyltriethoxysilane in ethanol-water mixture. The resulting products were investigated using Fourier transform infrared (FTIR) spectroscopy, X-ray diffraction (XRD), thermogravimetric analysis (TG). XRD patterns demonstrated that silane was intercalated into the montmorillonite gallery, indicated by increasing basal spacings. These intercalated silanes probably adopt bilayer arrangement models within the montmorillonite and acid-activated montmorillonites interlayer spaces. TG and DTG curves indicate that acidification results in a decrease of the thermal stability of the resultant montmorillonites. Silane grafting leads to a surface property transformation of montmorillonite from hydrophilicity to lipophilicity and an increase of the thermal stability of the condensed silanes.
35 citations
TL;DR: In this article, the fractal Frenkel-Halsey-Hill model and Neimark-Kiselev model were applied to quantitatively evaluate the heterogeneities of organo-montmorillonite surface by analyzing low-pressure nitrogen gas adsorption isotherms at 77 K.