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A novel bifunctional Ti–Fe kaolinite composite with excellent adsorption and photocatalytic properties was synthesized by a simple precipitation method. X-ray diffraction analysis and high-resolution transmission electron microscope analysis confirmed the existence of rutile phase TiO 2 and amorphous iron in the composite. The specific surface area of the Ti–Fe kaolinite composite is 5.5 times higher than that of the original kaolinite. The composite was used as an adsorbent as well as photocatalyst for Cr(VI) removal. The results indicate that the low pH is favorable to the Cr(VI) removal by the composite and the removal rate of Cr(VI) reached 87% at pH 3.0. Visible light irradiation obviously increased the removal of Cr(VI) by the composite and greatly shortened reaction equilibrium time, which may be attributed to the photocatalytic reduction of Cr(VI) to Cr(III) by TiO 2 associated with simultaneous redox cycle of Fe(III)/Fe(II). Various common co-existing ions did not show obvious effects on the removal of Cr(VI) by the composite. The composite exhibited very high stability for the Cr(VI) removal. The adsorption models and thermodynamics of Cr(VI) onto the composite were studied. [ABSTRACT FROM AUTHOR]

new approach was developed to prepare high-performance isobutylene-isoprene rubber/swollen organoclay nanocomposites by shear mixing. Compared with traditional melt compounding method, better dispersion of nanoclay layers in rubber matrix was verified through transmission electron microscopy (TEM) and X-ray diffraction (XRD). The nanocomposites also exhibit significantly improved mechanical properties and gas barrier property. As a mechanism, the molecules of organic swelling agent play a vital role in accelerating the diffusion and intercalation of the matrix molecules. [ABSTRACT FROM AUTHOR]