title: Removal of Anionic Dyes from Water by Potash Alum Doped Polyaniline: Investigation of Kinetics and Thermodynamic Parameters of Adsorption.
abstract: Polyaniline was synthesized by the oxidative polymerization method by using ammonium persulfate as an oxidant. The positive charge in the backbone of the polymer was generated by using Potash alum as a dopant. Scanning electron microscopy (SEM), Fourier transform infrared (FTIR), X-ray fluorescence (XRF), and X-ray diffraction (XRD) techniques were used for characterization of doped polyaniline. The doped polyaniline can be used for selective adsorption of various dyes (selectively sulfonated dyes) from aqueous solution. Adsorption studies regarding the effect of contact time, initial dye concentration, pH, doses of adsorbent, and temperature on adsorption kinetics were investigated. The influence of other anions like Cl(-), NO3(-), and SO4(2-) on the adsorption density of dyes onto doped polyaniline was also explored. Langmuir isotherm and pseudo-second-order kinetics were found to be the most appropriate models to describe the removal of anionic dyes from water through adsorption. Thermodynamic parameters such as free energy (ΔG(0)), enthalpy (ΔH(0)), and entropy (ΔS(0)) changes were also evaluated. The interaction of dyes with doped polyaniline was also investigated by FTIR and UV spectroscopy.
authors.affiliation: School of Chemistry, Sambalpur University, Sambalpur, Odisha, India 768019.
authors.forename: Braja N
authors.initials: BN
authors.lastname: Patra
authors.affiliation: School of Chemistry, Sambalpur University, Sambalpur, Odisha, India 768019.
authors.forename: Deola
authors.initials: D
authors.lastname: Majhi
mesh_terms: D000534:Alum Compounds / Q000737:chemistry*; D000814:Aniline Compounds / Q000138:chemical synthesis / Q000737:chemistry*; D000838:Anions / Q000737:chemistry / Q000302:isolation & purification; D004396:Coloring Agents / Q000737:chemistry / Q000302:isolation & purification*; D045424:Complex Mixtures / Q000737:chemistry*; D006863:Hydrogen-Ion Concentration; D007700:Kinetics; D008855:Microscopy, Electron, Scanning; D008956:Models, Chemical; D015394:Molecular Structure; D012996:Solutions; D013052:Spectrometry, X-Ray Emission; D017550:Spectroscopy, Fourier Transform Infrared; D055672:Static Electricity; D013816:Thermodynamics; D014867:Water / Q000737:chemistry*; D018508:Water Purification / Q000379:methods; D014961:X-Ray Diffraction
chemical_list: D000534:Alum Compounds; D000814:Aniline Compounds; D000838:Anions; D004396:Coloring Agents; D045424:Complex Mixtures; D012996:Solutions; C416807:polyaniline; C518454:potash; D014867:Water