Adsorption of Hg(II) from aqueous solution using thiourea functionalized chelating fiber

A fast and selective adsorbent for Hg(II) from aqueous solutions using thiourea (TU) functionalized polypropylene fiber grafted acrylic acid (PP-g-AA), PP-g-AA-TU fibers, was characterized by Fourier transforminfrared spectroscopy and X-ray photoelectron spectroscopy. The adsorption behavior of the functionalized chelating fibers for Hg(II) was investigated by static adsorption experiments, and the effects of some essential factors on adsorption of Hg(II) were examined, such as pH, initial concentration, adsorption time, coexisting cations, and temperature. The results showed that the adsorptive equilibrium could be achieved in 10 min, and the equilibrium adsorption quantity of PP-g-AA-TU fibers was 20 times that of PP-g-AA fibers. The PP-g-AA-TU fibers showed a very high adsorption rate and a good selectivity for Hg(II) over a wide range of pH. The adsorption isotherm can be well described with Langmuir model, with the maximum adsorption capacity for Hg(II) up to 52.04 mg.g(-1) and the removal of Hg(II) more than 97%. The kinetic data indicate that the adsorption process is best-fitted into the pseudo-second-order model. (C) 2016 The Chemical Industry and Engineering Society of China, and Chemical Industry Press. All rights reserved.