A heterogeneous monolayer model with two types of binding site was utilized to analyze and interpret the adsorption mechanism of Fe³⁺, Al³⁺ and Cu²⁺ ions on chitosan films at 25–55 °C and pH 6. Theoretical results of statistical physics calculations indicated that the adsorption of Fe³⁺, Al³⁺ and Cu²⁺ ions was multi-ionic where two adsorption sites (i.e., amino and hydroxyl groups) were involved but with a different contribution degree. Adsorption capacities at saturation ranged from 125.99 to 512.27 mg/g for tested operating conditions. The removal mechanism of Al³⁺ and Cu²⁺ ions was exothermic, whereas the adsorption of Fe³⁺ ions was endothermic.

利用具有两种结合位点的异质单层模型来分析和解释 Fe ³⁺、Al ³⁺和 Cu ²⁺离子在 25–55 °C 和 pH 6 条件下在壳聚糖薄膜上的吸附机制。 统计物理的理论结果计算表明Fe ³⁺、Al ³⁺和Cu ²⁺离子的吸附是多离子的，其中涉及两个吸附位点（即氨基和羟基），但贡献程度不同。对于测试的操作条件，饱和吸附能力范围为 125.99 至 512.27 mg/g。Al ³⁺和Cu ²⁺离子的去除机理是放热的，而Fe的吸附³⁺离子是吸热的。