关键词: 单宁, 固化, 胶原纤维膜, 吸附, Pb(Ⅱ), Hg(Ⅱ)

Abstract: A novel adsorption membrane with excellent physical properties was prepared by immobilizing bayberry tannin onto hide collagen fiber membrane. The equilibrium adsorption capacities of the membrane to Pb(Ⅱ) and Hg(Ⅱ) were 39.9 mg•g^-1 and 75.2 mg•g^-1 respectively at 303 K when the equilibrium concentrations of Pb(Ⅱ) and Hg(Ⅱ) were 192.1 mg•L^-1 and 23.5 mg•L^-1.Higher temperature led to higher adsorption capacity. The adsorption isotherm of Pb(Ⅱ) on the tannin immobilized membrane could be described by the Langmuir model, however, the isotherms of Hg(Ⅱ) tended to be fitted by the Freundlich model. The data of adsorption rate could be well described by the pseudo-second-order rate model. Continuous adsorption experiments indicated that multi-layer membranes were efficient for the removal of Pb(Ⅱ) and Hg(Ⅱ) from water. The membrane was easy to be regenerated by 0.1 mol•L^-1 HNO₃ after continuous adsorption and no considerable change of its adsorption property was observed after adsorption and desorption cycles.

Key words: 单宁, 固化, 胶原纤维膜, 吸附, Pb(Ⅱ), Hg(Ⅱ)