Preparation of Strontium-Barium Titanate Based on Glass Fiber Filter and Its Adsorption Behavior for Cadmium Ion

Abstract:

Strontium-barium titanate based on glass fiber filter (BBST) was prepared by the citrate acid complex sol-gel method and characterized by X-ray diffraction (XRD), scanning electron microscope (SEM) and fourier transform infrared spectrophotometer (FT-IR). The adsorption behavior of BBST for cadmium ion in distilled water was investigated. The results show that the strontium-barium titanate could bond with glass fiber filter through Si-O-Ti and B-O-Ti bonding to produce a new sort of porous block adsorbent. The cadmium ion could be quantitatively retained in the medium with pH value range of 4-8, and the capacity of adsorption was 9.8 mg·g-1. The adsorption behavior followed Freundlich adsorption isotherm model and HO pseudo-second-order kinetic equation. The enthalpy changes (△H) of the adsorption process was 17.241 kJ·mol-1. At various temperatures, Gibbs free energy changes (△G) were negative, and entropy changes (△S) were positive. These showed that the adsorption of cadmium ion by BBST was endothermic and spontaneous physical process.

Key words:strontium-barium titanate; glass fiber filter; adsorption behavior; cadmium ion