Abstract
A new composite absorbent with multifunctional and environmental-friendly structures was prepared using chitosan, diatomite and polyvinyl alcohol as the raw materials, and glutaraldehyde as a cross-linking agent. The structure and morphology of the composite absorbent, and its adsorption properties of Hg(II) in water were characterized with Fourier transform infrared (FT-IR) spectra, scanning electron microscope (SEM), X-ray diffraction (XRD), Brunauer Emmett Teller (BET) measurements and ultraviolet–visible (UV–Vis) spectra. The effect of the pH value and contact time on the removal rate and absorbance of Hg(II) was discussed. The adsorption kinetic model and static adsorption isotherm and regeneration of the obtained composite absorbent were investigated. The results indicated that the removal of Hg(II) on the composite absorbent followed a rapid adsorption for 50 min, and was close to the adsorption saturation after 1 h, which is in accord with the Langmuir adsorption isotherm model and the pseudo-second-order kinetic model. When the pH value, contact time and the mass of the composite absorbent was 3, 1 h and 100 mg, respectively, the removal rate of Hg(II) on the composite absorbent reached 77%, and the maximum adsorption capacity of Hg(II) reached 195.7 mg g−1.
Highlights
As is known, water is one of the basic necessities required for the sustenance and continuation of life
The results indicated that the removal of Hg(II) on the composite absorbent followed a rapid adsorption for 50 min, and was close to the adsorption saturation after 1 h, which is in accord with the Langmuir adsorption isotherm model and the pseudo-second-order kinetic model
A new composite absorbent was prepared by a cross-linking reaction of chitosan, diatomite and glutaraldehyde
Summary
Water is one of the basic necessities required for the sustenance and continuation of life. Different types of adsorbents such as polymers [8,9,10], amorphous silica [11,12,13,14] and clays [15,16,17,18,19] have been reported These adsorption materials have some shortcomings, such as low mechanical and thermal stability, poor removal efficiency and high cost, it is very important to develop new adsorption materials. As a natural macromolecule material, chitosan has drawn particular attention as a potential effective sorbent due to its low cost and high content of active functional groups such as amino and hydroxyl groups In this context, various chitosan–natural or synthetic polymers composites, such as natural and cross-linked chitosan [20], chemical modification of chitosan [21], chitosan/cellulose [22], chitosan/polyacrylamide [23] and chitosan/phenylthiourea resin [24], have been applied to adsorption of various heavy metals.
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
