Modification Of Basalt Fiber For Adsorption Of Heavy Metal Ions From Water

In this paper,a kind of environment-friendly material basalt fiber was used as the base material.It was coated with dopamine,then modified by polyvinylamine,of which the product named BF-A.Then BF-A was modified by sodium chloroacetate,and the product was named BF-C.Scanning electron microscopy（SEM）,Fourier transform infrared spectroscopy（FTIR）and X-ray photoelectron spectroscopy（XPS）were used to study the microstructure and surface material struture on both fibers.Then the two kinds of fibers were applied to studying the adsorption properties of Cu²⁺.The SEM images showed that the fiber surface was coated with polydopamine membrane,and through amination and carboxyl modification,the roughness of BF-A,BF-C surface increased;FTIR results showed that the amination and carboxylation modification occurred on the fiber surface..The results of static adsorption showed that the adsorption capacity of BF-A and BF-C on Cu²⁺increase with the increase of pH in the range of the experimental study.The adsorption isotherm experimental data were well fitted to Langmuir isotherm equation,which was proved that the adsorption was monolayer adsorption.The adsorption thermodynamics showed that the adsorption of Cu²⁺on BF-A was spontaneous endothermic process,while the reaction on BF-C was spontaneous exothermic process.The kinetic adsorption experimental data were well fitted to pseudo-second-order kinetic model.The results of the selectivity adsorption experiment showed that both fibers had a larger adsorption capacity for Cu²⁺than other mental ions.The results of XPS showed that the adsorption of Cu²⁺on BF-A and BF-C were the combination of chelation adsorption and electrostatic adsorption.The desorption experimental data showed that both fibers have high desorption rate in the dilute hydrochloric acid solution.