Research On Using Composite Materials Of Activated Carbon Load Ferrous Ion And Nano Zero-valent Iron To Remove Perchlorate In The Water

The physical and chemical properties of perchlorate are stable,it is soluble in water and difficult to be degraded,interferes with the human thyroid function,affects children's mental development,has potentially carcinogenic hazards,such as in the water pollution has been widely concerned.Activated carbon could adsorb perchlorate certainly and perchlorate is a kind of anionic,improving active carbon adsorption effect by adding positive charge on the surface of activated carbon,so the preparation of activated carbon composites with ferrous ions?GAC-Fe????to remove perchlorate in water.At the same time,the strong reducibility of nano zerovalent iron,which can effectively remove perchlorate in the water,combined nano zero-valent iron high reducibility and activated carbon adsorption,then making the material of activated carbon composites with nano zero-valent iron?GAC-Fe⁰?.This study chooses ferrous sulfate iron,making the material of GAC-Fe???by the method of infiltrating the activated carbon and ferrous sulfate under 110 ? for24 h,the using potassium borohydride?KBH₄?and nano zero-valent iron sulfate iron reacts with activated carbon after infiltration under 110?for 24 h to make the material of GAC-Fe⁰.Finding the characterization of the two materials by XRD and SEM.The results show that the GAC-Fe???loads the ferrous ion successfully,GAC-Fe⁰ also successfully loads the nano zero-valent iron.Research on the removal effect of perchlorate by GAC-Fe???,and exploring the different effects of reaction conditions when removing perchlorate,mainly includes: the iron content,perchlorate,initial concentration,temperature and pH.The experimental results show that,when the iron content is 1.3113%,the removal rate of perchlorate si biggest;The higher of the initial concentration,the removal effect of perchlorate is worse;Removal efficiency is higher with the increase of temperature,and the temperature is 120? the removal effect is stable;Under the condition of partial acid is more advantageous to perchlorate removing,the removal rate when pH is 6.03 is the largest,the removal efficiency of perchlorate is inhibited in alkaline conditions.To remove perchlorate by the material of GAC-Fe⁰ through the different influence factors,mainly includes: the iron content,perchlorate,initial concentration,temperature,pH value and coexisting ions,and compare the removal effect of perchloratethe by three kinds of material of GAC,the GAC-Fe???and GAC-Fe⁰.The experimental results show that when the iron content is 2.4479%,the removal effect is best;Adsorption capacity is increasing with the increase of initial concentration,the removal rate with the increase of initial concentration is decline;When the temperature is 80 ?,the removal rate is the largest,removal rate declines with raising the temperature;With increasing pH increase under acid condition,the removal effect is the best when pH value is 5.35,removal rate changed little in alkaline condition;Cl-had weak inhibitory effection on removing perchlorate,CO32-have a stronger inhibitory effection,BrO3-have a stimulate effection;Comparing the removal effection of perchlorate of GAC,the GAC-Fe???and GAC-Fe⁰ found that removal effect of GAC-Fe⁰ is best.To explore the reaction mechanism of removing perchlorate by GAC-Fe???and GAC-Fe⁰ as well as to analyze the reaction products,and found in the process of removing perchlorate has physical and chemical adsorption,analyzing the reaction products found that there is chloride ion,in the process of reaction may be associated with other products in the middle.