Research On Preparation And Adsorption Performance For Heavy Metal Ions Of Graphene Oxide Composite

Among methods employed to remove heavy metal ions from wastewater and soil,adsorption and chemical curing/stablization method are an economically viable method.The governance effects are closely related to the structure and adsorption performance of adsorbent material.In this paper,the aminated modified graphene oxide composite was fabricated by graphene oxide?GO?as the matrix.The synthesis process and adsorption capacity for Pb²⁺and Cd²⁺removal were studied by FTIR,XRD,NMR and XPS.In this paper,bacterial cellulose/graphene oxide?BC/GO?composite was prepared by ultrasonic method.The effects of different factors on the adsorption properties for Pb²⁺and Cd²⁺removal and the adsorption mechanism for Pb²⁺and Cd²⁺removal were discussed.After systematic experiments,the main conclusion is as follows:?1?The adsorption experiments were conducted by taking advantage of the traditional stirring method at 28±2?and a 300 rpm agitation.All the adsorption experiments were performed in flasks filled with 0.4 g/L adsorbents and the initial concentration was 100 mg/L.Because of the introduction of amino group and C-Si-OH surface group,Aminoated magnetic graphene oxide?N-mGO?greatly improved the adsorption properties.The removal rates of Pb²⁺and Cd²⁺in the slurry treated by N-mGO were 86.40%and 88.12%,respectively,which were significantly better than that of GO and mGO.?2?BC/GO composite hydrogel was prepared by ultrasonic method.The equilibrated adsorption capacity of Pb²⁺and Cd²⁺were 224.5 mg/g and 194.0 mg/g,respectively,which was significantly higher than that of BC.The possible reasons for the improvement of adsorption performance were as follows:1)The ultrasonic action caused the hydrogen bond between O?3?H···O?5?in BC was broken,the accessibility of O?3?H enhanced,so that the adsorption capacity of BC was increased;2)GO was adhered to the surface of BC fiber which formed a loose three-dimensional structure with relatively uniform pores.This structure increased the contact sites with heavy metal ions;3)The introduction of carboxyl groups in GO enriched the oxygen-containing groups of BC,which increased the adsorption site of BC increased the contact sites with heavy metal ions;3)The introduction of carboxyl groups in GO enriched the oxygen-containing groups of BC,which increased the adsorption site of BC for Pb²⁺and Cd²⁺removal.?3?The adsorption experiments were conducted by taking advantage of the traditional stirring method at 28±2?and a 300 rpm agitation.All the adsorption experiments were performed in flasks filled with 0.4 g/L adsorbents and the initial concentration was 100 mg/L.The adsorption capacity for Pb²⁺removal of Fe₃O₄@BC/GO reached 147.3 mg/g,which was far better than 40.0 mg/g by BC after freeze drying?DBC?and batter than 85.2 mg/g by BC after freeze drying?DBC/GO?.?4?mGO,N-mGO and Fe₃O₄@BC/GO all had comparatively preferable adsorption capacity for the removal of Pb²⁺and Cd²⁺and stronger saturation magnetization.These materials can be quickly separated from water and slurry under the action of an external magnetic field after adsorption of heavy metal ions.The modified graphene oxide composite material,possessed the better adsorption capacity and the magnetic separation ability,had potential application value in the treatment of heavy metal pollution.