Characterization of modified silica aerogel using sodium silicate precursor and its application as adsorbent of Cu2+, Cd2+, and Pb2+ ions

International Journal of Industrial Chemistry

دوره 3، شماره 1، اسفند 2012، صفحه 105-112

نوع مقاله: research article

شناسه دیجیتال (DOI): https://doi.org/10.1186/2228-5547-3-20

نویسندگان

HR Pouretedal^{* 1}؛ M Kazemi²

¹Faculty of Applied Chemistry, Malek-ashtar University of Technology, Shahin-Shahr, 1387763681, Iran

²Department of Chemistry, Shahreza and Fadak Group, Islamic Azad University, Shahreza Branch, Isfahan, 37541-13115, Iran

چکیده

Sodium silicate (Na₂O/SiO₂ = 1:3.3) as a precursor is used to prepare silica aerogel. The prepared silica aerogel is modified by mercaptopropyl trimethoxysilane. The modified silica aerogel is characterized using Fourier transform infrared spectroscopy, Brunauer, Emmett, Teller method, and transmission electron microscopy. The adsorption and removal of Cu²⁺, Cd²⁺, and Pb²⁺ ions from aqueous samples using modified silica aerogel are studied. The experimental conditions such as pH of samples, initial concentration of cations, contact time, and adsorbent dose are optimized to attain the maximum adsorption capacity. The optimum values are obtained as follows: contact time = 30 min, adsorbent dose = 0.05 g for Cd²⁺and Pb²⁺ ions and 0.1 g for Cu²⁺ ions, pH = 6 for Cd²⁺ and Pb²⁺ ions, and pH = 4 for Cu²⁺ ions. The equilibrium data are fitted well by the Langmuir and Freundlich isotherm models. The adsorption capacities for Cu²⁺, Cd²⁺, and Pb²⁺ ions are found 90.1, 181.8, and 250.0 mg/g, respectively.

کلیدواژه‌ها

Silica aerogel؛ Adsorbent؛ Sodium silicate؛ Metal ion؛ Modification