Studies on the adsorption behaviors of Pb(II) onto an acyl-thiourea resin

ABSTRACT

In this paper, an acyl-thiourea resin (PIDTR) was synthesized and its adsorption performances to Pb(II) were investigated by adsorption tests, scanning electron microscopy (SEM), Fourier transform infrared spectra (FTIR), and X-ray photoelectron spectroscopy (XPS) analyses. A pH of 6.0 was found to be the optimum pH to obtain the maximum adsorption capacity in 12 hours of equilibration time. The Langmuir model was well fitted to the adsorption data with adsorption capacity of 0.756 mmol · g⁻¹. The adsorption kinetics showed that the adsorption process experienced liquid film diffusion and chemical reaction. The thermodynamic studies indicated that the adsorption for Pb(II) was spontaneous and endothermic. The results of SEM suggested that Pb(II) adsorbed on the surface of PIDTR. The FTIR and XPS analyses further confirmed Pb(II) might chemisorb onto PIDTR surfaces and N–Pb, O–Pb, and S–Pb were formed with the breakage of C˭O, C˭S, and N-H bonds in the PIDTR molecule.

GRAPHICAL ABSTRACT

KEYWORDS:

• Adsorption
• lead
• synthesis
• thiourea resin

Additional information

Funding

The authors would like to thank National Nature Science Foundation of China (Grant No.21776320) and National Basic Research Program of China (863 program, Grant No.2013AA064102) for the financial support and also thank the advanced research center and modern analysis and testing center of Central South University for analysis and test.