Adsorption Enhancement of Heavy Metal Ions Using Chitosan-Modified Natural Zeolite Nanocomposite

摘要

This research is to modify the natural zeolite (NZ) with chitosan (chit) as an adsorbent for Pb(II) ion adsorption. Chit-NZ nanocomposite was synthesized using NZ which has been physically and chemically activated and modified with chitosan in nano size to enhance their adsorption activity. The characterization was conducted by Fouriertransform infrared (FTIR) spectroscopy and transmission electron microscope (TEM). According to FT-IR result, there were hydroxyl and amine groups in Chit-NZ nanocomposite at 3645 and 3290 cm~(-1), respectively. The formed Chit-NZ nanocomposite from TEM image has particle size approximately 40 nm. Chit-NZ nanocomposite and NZ as a comparison was observed for Pb(II) adsorption using atomic absorption spectrometry (AAS). According to result, the adsorption percentage of Pb(II) on NZ and Chit-NZ nanocomposite were 43.83 and 49.91 %, respectively at pH of 6.0 and initial Pb(II) concentration of 1500 ppm. The Pb(II) adsorption percentage using Chit-NZ nanocomposite was 99.68 % with optimum conditions at pH of 6.0, Pb(II) concentration of 300 ppm, and contact time of 30 min. The kinetic study showed that Pb(II) adsorption followed a pseudo second-order kinetic model with a reaction rate constant, k of 9.74 × 10~(-3) (g/mmol)~(-1)min~(-1).