Ammonia Adsorption Materials Modification And Removal Efficiency Of Perfluorochemicals In Water

Perfluorooctane sulfonate(PFOS)and perfluorooctanoic acid(PFOA)are typical perfluorochemicals,widely distributed in different pollution level in the global scope of environmental media and organism,emissions of industrial wastewater is the important way of it into the environment.because of their unique physical and chemical properties,released into the environment in an important way of the discharge of industrial wastewater.Currently,there are two main treatment methods including chemical degradation and absorption for removing PFOS and PFOA from wastewater.At present,the wastewater of PFOS and PFOA processing method is given priority to the chemical method and physical method,because its concentration is not high,direct application of chemical degradation efficiency is low,due to the high efficiency and easy operation etc.,adsorption method is an effective method to remove the water phase of PFOS and PFOA.PFOS and PFOA have been prepared by coated microparticles,but there is a certain amino loss in the adsorption process,which affects the adsorption effect.In this paper,the preparation conditions of the coated microparticles were improved,and the amino coupling agent was replaced by the n-(2-ammonia ethyl)-3-amino-propyl trimethoxysilane and the control of water alcohols by 3/100.The results show that the optimized coated microparticles were improved,and PFOS and PFOA have stable and high adsorption,desorption efficiency and good recycling.The saturation adsorption on PFOS and PFOA was 28.5 and 24.3 mg/g respectively.Chitosan is easily chemically modified by the presence of amino in its structure.Adsorption and desorption of PFOS and PFOA in water by using chitosan material were discussed.The saturation adsorption of chitosan pellets on PFOS and PFOA was 43.5 and 35.7 mg/g respectively,and the saturated adsorption capacity of chitosan pellets on PFOS and PFOA was 125 and 110 mg/g respectively.Ion exchange resin is a kind of polymer compound which is characterized by ion exchange and adsorption and has functional groups.It has many advantages such as fast adsorption speed,high mechanical strength,strong anti-pollution ability,good stability and recyclability.The adsorption and desorption performance of four different kinds of resin were evaluated by using the four common amine functional groups anion exchange resin to remove PFOS and PFOA in water.The dynamic experiment showed that the absorptive effect of the IRA-900 resin was selected,and the velocity of the adsorption was larger effect,using 0.5 mol/L Na Cl+0.5 mol/L Na OH as the deattachment,IRA-900 was better and recyclable.The micro particles have good recycling performance,the adsorption capacity of chitosan material is large,and the resin materials are easy to get and economic.These three kinds of materials are suitable for different application scenarios.Through adsorption and desorption operation,the PFCs in wastewater can be enriched,followed by subsequent chemical treatment.