Abstract:

The adsorption behavior of cross-linked chitosan prepared with epichlorohydrin to trace cadmium (Ⅱ) in water was investigated. One-factor-at-a-time and orthogonal array methods were applied to maximize adsorption of cross-linked chitosan to cadmium. Range analysis proved that the most significant factor affecting adsorption was pH of solution, followed by amount of added cross-linked chitosan. The average removal rate of Cd2+ was 97.4% with a RSD of 8.4% (n = 6) and the average saturated absorption capacity was 45.6 mg/g, suggesting good precision. The enrichment of cadmium with cross-linked chitosan was applied to the atomic absorption spectrometric determination of trace cadmium in brewery industrial water. This method is fast, effective and simple for the determination of trace cadmium in food industrial water with a high recovery of 97.2%－103.3%.

Key words: cross-linked chitosan, separation and enrichment, cadmium, orthogonal array design, atomic absorption spectrometry