Adsorption of phenol from aqueous solutions using interlayer modified titanate nanotubes

Abstract BACKGROUND Layered titanate nanostructures have long been studied as efficient adsorbents for different kinds of pollutants such as heavy metals and dye cations. As to the electro‐neutral and anionic organic pollutants, titanates show relatively low adsorption capacity due to a negatively charged surface and lack of organophilic affinity. This research focuses on the interlayer modification of titanate nanotubes for adsorption of this kind of organic pollutants. Phenol was chosen as a representative target. RESULTS Two surfactants, hexadecyl trimethyl ammonium bromide (HTAB) and dodecyl dimethyl benzyl ammonium bromide (DDBAB), were chosen as organic modifier for the interlayer modification. Detailed characterization proved that surfactant molecules were intercalated into the interlayer and surface properties of titanates were successfully modified. Adsorption behavior of phenol was then systematically investigated. Results show that DDBAB modified titanates are efficient phenol adsorbents, possessing better performance than HTAB modified titanates. The high adsorption capacity is attributed to the special structure of titanates and the affinity between phenyl groups in DDBAB and phenol. Subsequently, thermally induced phase change of spent adsorbents led to complete regeneration. CONCLUSION Interlayer modified titanate nanotubes were efficient phenol adsorbents with a maximum adsorption capacity of 226.24 mg g ‐1 . Complete regeneration of spent adsorbents was also achieved. © 2018 Society of Chemical Industry