Preparation Of Functionalized Magnetic Graphene Oxide Materials And Their Adsorption Properties For Arsenic

In this paper,two functionalized magnetic graphene oxide materials,As???ion-imprinted polymer modified magnetic graphene oxide and ionic liquid modified magnetic graphene oxide,were developed and characterized for As???and As?V?in water.The adsorption is removed and the effect is good.The main contents are as follows:1.Preparation and Adsorption Characteristics of Arsenic???Ion-imprinted Polymer:A novel ion-imprinted polymer was prepared on magnetic graphene oxide nanosheets?MGO-IIP?with arsenic ion?As????is used as template ion,3-merraptnpropylt rimethnxysilane?MPTS?as the functional monomer,tetraethylorthosilicate?TEOS?as the crosslinking agent.The correspondingly non-imprinted material was synthesized in the same manner for comparison?MGO-NIP?.The MGO-IIP?NIP?was characterized using scanning electron microscope?SEM?,fourier transform infrared spectroscopy?FTIR?,X-ray diffraction?XRD?and magnetization curves?Vsm?.The synthesized MGO-IL was used as an adsorbent,we investigated the effects of solution pH,adsorption time,adsorption temperature,initial solution concentration,co-existent ions and reuse effect of materials on the adsorption.Under optimal experimental conditions,the maximum adsorption capacities of MGO for As???is 148.1 mg g^-1,the adsorption equilibrium can be reached in only 20 minutes,with and the imprint factor was 2.35.The adsorption process obeys the Langmuir model and the pseudo-second-order model,which is a spontaneous endothermic process.In the presence of other co-existing anions,MGO-IIP still has an excellent adsorption effect on As???and can be reused 4 times,therefore,it has application value in the treatment of arsenic-containing wastewater.The adsorption mechanism of MGO-IIP for As???is surface complexation and physical adsorption.It is found that the adsorption mechanism of As???by MGO-IIP material is surface complexation and physical adsorption.2.Ionic Liquid Modification of Magnetic Graphene Oxide and Its Adsorption Properties for As???and As?V?:GO was prepared by the modified Hummers method,then MGO was prepared,and then MGO-IL adsorption material was synthesized by supported ionic liquid?IL?with MGO as a carrier.The synthesized materials were characterized by SEM,FTIR,XRD,VSM and thermogravimetric analyzer?TG?.The adsorption effect of MGO-IIP was investigated,and the type of ionic liquid,pH value of solution,adsorption time,temperature,initial solution concentration,coexisting anion and repeated use of materials were discussed.The experimental results show that the adsorption equilibrium is reached within 30min,the maximum adsorption capacity of the material for As???is 160.65 mg g^-1,and the maximum adsorption capacity for As?V?is 104.13 mg g^-1.MGO-IL can be quickly separated from the solution by an external magnetic field.The material can be reused 5 times and its adsorption capacity is not significantly reduced.In addition,common coexisting anions do not interfere with the absorption of As???and As?V?.Compared with MGO,the adsorp tion amount of As???and As?V?by MGO-IL is greatly increased,and the equilibrium time is significantly shortened.The adsorption mechanism of arsenic substances by MGO-IL was explored.In addition to electrostatic attraction,the adsorption mechanism o f As???on MGO-IL was mainly surface complexation.