Synthesis of PANI/AlOOH composite for Cr(VI) adsorption and reduction from aqueous solutions.

In this study, polyaniline rafted to the surface of AlOOH (PANI/AlOOH) composites were successfully synthesized and applied for chromium (Cr(VI)) adsorption from aqueous solutions. Cr(VI) adsorption isotherms were described by Langmuir model well and the maximum adsorption capacity was 66.77 mg/g at pH=5 and T=298 K. Cr(VI) adsorption was attributed to chemisorption and outer‐sphere surface complexation. The interaction mechanism was further investigated by Fourier transform infrared spectroscopy, transmission electron microscopy‐energy dispersive spectroscopy and X‐ray photoelectron spectroscopy techniques, and the results suggested the partially reduction of Cr(VI) to Cr(III). Cr(VI) removal was mainly related with the electrostatic attraction and chelation of different Cr(VI)/Cr(III) species with protonated nitrogen‐containing functional groups (‐NH+, ‐NH‐) on PANI/AlOOH. PANI/AlOOH composites were synthesized and applied as adsorbent for Cr(VI) adsorption from aqueous solutions. Surface adsorbed Cr(VI) could be reduced to Cr(III). Cr(VI) removal was mainly related with the electrostatic attraction and chelation of different Cr(VI)/Cr(III) with protonated nitrogen‐containing functional groups (‐NH+, ‐NH‐) on PANI/AlOOH. [ABSTRACT FROM AUTHOR]