title: Evaluation of adsorption capacities of humic acids extracted from Algerian soil on polyaniline for application to remove pollutants such as Cd(II), Zn(II) and Ni(II) and characterization with cavity microelectrode.
abstract: The adsorption capacities of new humic acids isolated from Yakouren forest (YHA) and Sahara (Tamenrasset: THA) soils (Algeria) and commercial humic acid (PFHA) on polyaniline emeraldine base (PEB) were studied at pH 6.6. Also the adsorption of heavy metals such as Cd2+, Zn2+ and Ni2+ on humic acid-polyaniline systems (HA-PEB) was investigated at the same conditions. HA-PEB compounds were characterized by scanning electron microscopy (SEM), infrared spectrometry and cavity microelectrode. In addition, batch adsorption and cavity microelectrode were used in the adsorption study of Cd2+, Zn2+ and Ni2+ on HA-PEB. To develop biocaptors of polluting metals using a cavity microelectrode modified by HA-PEB systems, the adsorption kinetic and adsorption capacity were investigated. The SEM analysis showed that the presence of humic acid affected the PEB surface and caused the formation of a granular morphology. The maximum adsorption capacities (q(max)) of PFHA, THA and YHA determined by adsorption isotherms were 91.31, 132.1 and 151.0 mg/g, respectively. Batch adsorption results showed that q(max) of Cd2+, Zn2+ and Ni2+ on HA-PEB followed the order: THA-PEB > YHA-PEB > PFHA-PEB. The voltammograms obtained with HA-PEB modified cavity microelectrode showed the appearance of new redox couples reflecting the adsorption of HA on PEB. Metal-humic acid-polyaniline voltammograms were characterized by appearance of oxidation-reduction couples or reduction wave corresponding to metal. Finally, the result may be exploited to develop a biocaptor based on the cavity microelectrode amended by THA-PEB and YHA-PEB.
authors: Center of Scientific Research and Technical in Physical and Chemical Analysis, Algiers 16004, Algeria. achour_t@yahoo.fr
authors: Achour
authors: A
authors: Terbouche
authors: Chafia Ait
authors: CA
authors: Ramdane-Terbouche
authors: Didier
authors: D
authors: Hauchard
authors: Safia
authors: S
authors: Djebbar
mesh_terms: D000814:Aniline Compounds / Q000737:chemistry*; D002104:Cadmium / Q000302:isolation & purification*; D006812:Humic Substances; D008839:Microelectrodes; D009532:Nickel / Q000302:isolation & purification*; D012987:Soil / Q000737:chemistry*; D012989:Soil Pollutants / Q000302:isolation & purification*; D015032:Zinc / Q000302:isolation & purification*
chemical_list: D000814:Aniline Compounds; D006812:Humic Substances; D012987:Soil; D012989:Soil Pollutants; C416807:polyaniline; D002104:Cadmium; D009532:Nickel; D015032:Zinc