Isotherms and kinetic study of ultrasound-assisted adsorption of malachite green and Pb2+ ions from aqueous samples by copper sulfide nanorods loaded on activated carbon: Experimental design optimization

Ebrahim Sharifpour; Hossein Zare Khafri; Mehrorang Ghaedi; Arash Asfaram; Ramin Jannesar

doi:10.1016/j.ultsonch.2017.07.030

Isotherms and kinetic study of ultrasound-assisted adsorption of malachite green and Pb²⁺ ions from aqueous samples by copper sulfide nanorods loaded on activated carbon: Experimental design optimization

Ultrason Sonochem. 2018 Jan;40(Pt A):373-382. doi: 10.1016/j.ultsonch.2017.07.030. Epub 2017 Jul 22.

Authors

Ebrahim Sharifpour¹, Hossein Zare Khafri², Mehrorang Ghaedi³, Arash Asfaram², Ramin Jannesar⁴

Affiliations

¹ Medicinal Plants Research Center, Yasuj University of Medical Sciences, Yasuj, Iran.
² Department of Chemistry, Yasouj University, Yasouj 75918-74831, Iran.
³ Department of Chemistry, Yasouj University, Yasouj 75918-74831, Iran. Electronic address: m_ghaedi@mail.yu.ac.ir.
⁴ Department of Pathology, Yasuj University of Medical Sciences, Yasuj, Iran.

PMID: 28946436
DOI: 10.1016/j.ultsonch.2017.07.030

Abstract

Copper sulfide nanorods loaded on activated carbon (CuS-NRs-AC) was synthesized and used for simultaneous ultrasound-assisted adsorption of malachite green (MG) and Pb²⁺ ions from aqueous solution. Following characterization of CuS-NRs-AC were investigated by SEM, EDX, TEM and XRD, the effects of pH (2.0-10), amount of adsorbent (0.003-0.011g), MG concentration (5-25mgL^-1), Pb²⁺ concentration (3-15mgL^-1) and sonication time (1.5-7.5min) and their interactions on responses were investigated by central composite design (CCD) and response surface methodology. According to desirability function on the Design Expert optimum removal (99.4%±1.0 for MG and 68.3±1.8 for Pb²⁺ions) was obtained at pH 6.0, 0.009g CuS-NRs-AC, 6.0min mixing by sonication and 15 and 6mgL^-1 for MG and Pb²⁺ ions, respectively. High determination coefficient (R²>0.995), Pred-R²-value (>0.920) and Adju-R²-value (>0.985) all are good indication of best agreement between the experimental and design modelling. The adsorption kinetics follows the pseudo-second order model and adsorption isotherm follows the Langmuir model with maximum adsorption capacity of 145.98 and 47.892mgg^-1 for MG and Pb²⁺ ions, respectively. This adsorbent over short contact time is good choice for simultaneous removal of large content of both MG and Pb²⁺ ions from wastewater sample.

Keywords: Copper sulfide nanorods; Kinetic models; Malachite green; Pb(2+) ions; Response surface methodology; Ultrasound-assisted adsorption.