Keggin-type polyoxometalates supported on PANI-coated CuS: Synthesis, characterization and application as the efficient adsorbents for selective dye removal

• Published in: Journal of industrial and engineering chemistry (Seoul, Korea) 2019, 80(0), , pp.205-216
• Main Authors: Siadatnasab, Firouzeh, Karami, Kazem, Khataee, Alireza
• Format: Article
• Language: English
• Subjects: Adsorption; CuS@PANI; Dye removal; Keggin-type polyoxometalates; Nanohybrids; 화학공학
• ISSN: 1226-086X; 1876-794X
• DOI: 10.1016/j.jiec.2019.07.050

Keggin-type heteropoly acids (H3PMo12O40, H3PW12O40 and H4SiW12O40) were chemically loaded onto the surface of polyaniline-coated CuS(PANI@CuS) nanoparticles and used as efficient adsorbents for rapid adsorption of cationic pollutant dye in aqueous solutions at room temperature. [Display omitted] •Three novel CuS@PANI/POMs ternary hybrid nanomaterials were prepared.•These ternary hybrid nanomaterials were fully characterized by various techniques.•Nanohybrid 1 was formed from uniform and core–shell structures.•The hybrid nanomaterials were used as novel adsorbents for selective removing cationic dye.•These compounds could be readily recycled and reused. In this work, Keggin type polyoxometalates H3PW12O40 (PW12), H3PMo12O40 (PMo12) and H4SiW12O40 (SiW12), were supported on polyaniline (PANI)-coated CuS nanoparticles by a facile stepwise modification method. These novel nanohybrids 1–3 (denoted as CuS@PANI/PW12 (1), CuS@PANI/PMo12 (2), and CuS@PANI/SiW12 (3)) were fully characterized. The adsorption efficiency of these novel nanohybrids were evaluated for removing methylene blue (MB) and methyl orange (MO) that exhibited high selectivity and high adsorption rate for cationic MB rather than anionic MO. The adsorption results demonstrated a good ability to remove 25mgL−1 MB with the removal rates of ≥93%. The efficiency of nanohybrid 1 for the removal of MB was evaluated by several factors, such as pH, adsorbent dose, initial dye concentration and temperature. The adsorption isotherms and adsorption kinetic can be well described by the Langmuir isotherm model and the pseudo second order kinetic for MB, respectively. Moreover, the maximum adsorption capacity of MB reached 83.3mgg−1 in the study of the Langmuir adsorption isotherm, respectively. Thermodynamic studies show that the MB adsorption is a spontaneous endothermic process. The nanohybrids can be easily separated and reused without any change in performances and structures.