Adsorption of phenols from contaminated water through titania-silica mixed imidazolium based ionic liquid: Equilibrium, kinetic and thermodynamic modeling studies. Issue 10 (2nd October 2016)

• Record Type: Journal Article
• Authors: Ismail, Nor Atiqah; Bakhshaei, Shabnam; Kamboh, Muhammad Afzal; Abdul Manan, Ninie Suhana; Mohamad, Sharifah; Yilmaz, Mustafa
• Is Part Of: Journal of macromolecular science. Volume 53:Issue 10(2016)
• Page Start: 619
• Page End: 628
• Publication Date: 2016-10-02
• Subjects: Sol gel -- titania-silica -- ionic liquid -- kinetic and thermodynamic modeling studies; Polymers -- Periodicals; Polymerization -- Periodicals; 547.7
• DOI: 10.1080/10601325.2016.1212309
• Languages: English
• ISSNs: 1060-1325

Abstract

ABSTRACT: The present study describes the synthesis and characterization of titania-silica mixed imidazolium based ionic liquid (Ti-Si-IL ) as well as evaluation of its adsorption behavior towards the 2, 4-dinitrophenol (2, 4-DNP) and 2, 4, 6-trichlorophenol (2, 4, 6-TCP). SynthesizedTi-Si-IL adsorbent was characterized by Fourier transform infrared spectroscopy (FT-IR), field emission scanning electron microscopy (FESEM), BET surface area Brunauer-Emmett-Teller (BET), thermogravimetric analysis (TGA) and elemental analysis (CHN). The adsorption of 2, 4-DNP and 2, 4, 6-TCP onTi-Si-IL was investigated systematically by evaluating the effects of adsorbent dosage, initial pH, contact time and temperature. Satisfactory adsorption 95% and 65% for 2, 4-DNP and 2, 4, 6-TCP was observed at pH 4 and 6, respectively. The kinetic results for 2, 4-DNP and 2, 4, 6-TCP onTi-Si-IL indicated that the kinetic data follows pseudo-second-order model (R 2 = 0.9985 and 0.9750, respectively). Adsorption isotherms were fitted well by the Langmuir model for 2, 4-DNP ( qm = 44.64 mg g −1 at 318 K) and Freundlich model for 2, 4, 6-TCP ( KF = 0.63 mg g −1 at 318 K). The +Δ H ° and -Δ G ° values demonstrated that the adsorption of 2, 4-DNP was endothermic and spontaneous in nature. While the -Δ H ° and +Δ G ° values for 2, 4, 6-TCP adsorption demonstrated exothermic and comparatively nonspontaneous. During the removal process, the role of different functional groups, cyclic structure was monitored and found that the ionic property as well as π-π interactions of host molecules played important role in the extent of adsorption.