Study On The Preparation And Adsorption Performance Of Polyethyleneimine Modified Cellulose Adsorbent

Cellulose modified has been a hot spot in the research of heavy metal adsorption material.In order to optimize the cellulose pretreatment before modification and improve the adsorption performance,a new type of chelating adsorbent was studied in this article.The cellulose pretreated by microwave hydrogen peroxide before modification.Then succinic anhydride and polyethyleneimine were used to modified cellulose to preparation adsorption material MCCMV-SA-PEI.The changes of structure?properties and morphology were characterized by X-ray photoelectron spectroscopy(XPS)?thermogravimetric(TG)?scanning electron microscope(SEM)and infrared spectroscopy(FT-IR).The adsorption performance were investigated by remove Cd(?)?Pb(?)and Cr(?).The results were as follows:1.The hydrogen peroxide concentration?pretreatment temperature and pretreatment time were optimize by RSM.The optimal conditions obtained were a hydrogen peroxide concentration of 8.37%,a temperature of 90? and a retention time of 5.33 min.2.The amount of amino?carboxyl and N of MCCMv-SA-PEI were 2.61 mmol·g-1?4.64 mmol·g-1 and 4.88%,respectively.The result of FTIR?XPS and TG all shown the introduction of amino.The honeycomb structure appeared in the SEM images of MCCMV-SA-PEI indicated that the roughness and porosity increased.3.The optimum pH value of MCCMV-SA-PEI adsorption of Cd(?)?Pb(?)and Cr(VI)was 5?5.6 and 3.The sorption kinetics obeyed pseudo-second-order sorption kinetics.The adsorption process was controlled by the intra-particle diffusion and membrane diffusion process.The adsorption behavior of MCCMv-SA-PEI toward heavy metal ions was well-described by Freundlich model with remarkably high adsorption capacity(Cd(II)219.37 mg·g-1?Pb(II)357.14 mg·g-1 and Cr(?)96.1538 mg·g-1).4.Competitive adsorption have the effect on heavy metal ions adsorption,and the inhibitory effect of Pb(II)?Cd(II)and Cr(VI)in the presence of the four co-ions separately,follows the order:Ca(?)>Mg(?)>K(?)>Na(?).Besides,MCCMv-SA-PEI can be easily regenerated with HN03 and ultrasonic and reused up to at least three times with equivalent high adsorption capacity.The adsorption mechanism of MCCMv-SA-PEI may be a result of chelating adsorption.Overall,rapid and Environmental protection preparation,fast and efficient adsorption of heavy metals and high regeneration ability can make the MCCMv-SA-PEI a practical value biosorbent for heavy metal removal from water.