Preparation of Nano Passivation Material and Its Effect on Lead in Soil
In order to solve the problem of heavy metal pollution in farmland,the amidoximized poly-acrylonitrile/bentonite composite nanofiber was prepared by electrospinning technology.It was modi-fied with hydroxylamine hydrochloride aqueous solution to obtain an amidoximated fiber material(amidoximation rate of 38％),and its active sites were increased,thereby enhancing its adsorption of Pb ions.Composite fibers were used for exogenous heavy metal soil passivation experiments and pak-choi pot experiments.Scanning electron microscope(SEM)observed the smooth surface of the pre-pared fiber.Thermogravimetric(TG)analysis showed that bentonite increases the thermal stability of composite nanofibers.Fourier infrared spectroscopy(FTIR)analysis confirmed the successful combi-nation of MMT and PAN and the successful introduction of amidoxime groups.The water contact angle experiment proved that doping and modification improve the wettability of the fiber.Studies have shown that the maximum adsorption capacity of amidoximated polyacrylonitrile/bentonite com-posite nanofibers for Pb ions in aqueous solution is 92.390 mg/kg.The Pb contaminated soil passiv-ation test showed that the addition of composite fiber can reduce the effective Pb content in the soil,with a reduction rate of 89.53％.In the pot experiment,the fresh weight and dry weight of the test group were 7.54 g and 0.65 g,respectively,and the Pb content in the ground part and root was 0.46 mg/kg and 3.68 mg/kg,respectively,which reduced the Pb absorption of Chinese cabbage.It is expected to be a passivating material for Pb polluted farmland soil with certain application prospect.
polyacrylonitrilebentoniteelectrospinningsoilPbpassivation material
万方数据
维普
