Synthesis of titanium phosphate/polypyrrole nanocomposites for removal of methyl orange from water

Abstract In this paper, titanium (IV) phosphate (TiP), polypyrrole (PPy), and titanium (IV) phosphate‐polypyrrole (TiP/PPy) nanocomposites were synthesized for adsorption of methyl orange (MO) dye from water. X‐ray diffraction data showed the formation of pure samples with crystallite size 14.1 and 14.2 nm of TiP and TiP/PPy nanocomposite respectively. The specific surface area of TiP (77.127 m 2 g −1 ) was higher than PPy (17.004 m 2 g −1 ) and TiP/PPy nanocomposite (25.247 m 2 g −1 ). The equilibrium adsorption capacity ( q e ) was found to be 9.801 and 30.69 mg g −1 for PPy and TiP/PPy nanocomposite respectively. The Langmuir model was successfully fitted, and the TiP/PPy nanocomposite (69.4 mg g −1 ) had a greater maximum adsorption capacity ( q m ) than PPy (51.9 mg g −1 ). The MO adsorption removal efficiency was dependent on the pH of the solution and was found to be 86.7% and 30.7% for TiP/PPy nanocomposite and PPy respectively at pH 4. Thermodynamics studied confirmed the spontaneous and exothermic nature of the adsorption process. The presence of common ions decreased MO adsorption capacity and the maximum decrease was found for sodium carbonate. Electrostatic interaction, π–π stacking, and hydrogen bonding were responsible for adsorption of MO dye on the TiP/PPy nanocomposite and PPy.