Study On Adsorption And Removal Of 1,2,3,4-Tetrachlorobenzene By Activated Carbon And Mineral Materials

With the improvement of the level of economic development in China,the amount of municipal solid waste is increasing year by year,incineration power generation is the best way to reduce waste and maximize comprehensive benefits,but in the process of municipal waste incineration will be discharged highly toxic substances-dioxin.At present,the dioxin in the flue gas of the waste power plant is mainly removed by activated carbon adsorption,however,due to the difficulty of detection of dioxin,high cost of adsorbent,and there are still shortcomings of study on adsorbent and dioxins removal efficiency and the mechanism,affected the efficiency and cost of dioxin removal.This paper uses 1,2,3,4-tetrachlorobenzene model of dioxins,the adsorption properties of seven kinds of activated carbon and three kinds of mineral material on dioxins were studied,analysis the relationship between adsorption properties and pore structure and surface chemical properties of adsorbents;the effects of the combination of activated carbon and mineral materials on the removal of dioxins were studied,by changing the ratio of activated carbon and mineral material,the most suitable adsorbent for adsorbing dioxin was obtained.Study on removal of dioxins by activated carbon found that,the optimal pore size for activated carbon adsorption of dioxins was 2~3 nm in the mesopores;activated carbon iodine number was not related to the properties of activated carbon adsorpt dioxins,methylene blue adsorption and removal efficiency were positively correlated,the higher the methylene blue adsorption,the higher the removal efficiency of activated carbon;the removal efficiency increased with decreasing granularity of activated carbon,but due to the accumulation of resistance,removal efficiency is the highest when the granularity is 11.58 ?m,and does not increase with the granularity continues decrease;oxygen containing functional groups on the surface of activated carbon were not conducive to the removal of 1,2,3,4-tetrachlorobenzene,and the removal efficiency decreases with the increase of the oxygen content of activated carbon;at the initial stage of adsorption,the adsorption capacity was linearly correlated with the adsorption time,the initial stage adsorption rate was 23.3ng/g·min.Study on removal of dioxins by mineral materials found that,the removalefficiency of diatomite was the highest,followed by activated clay,organic clay removal efficiency was the worst,followed by 93.32%,86.06% and 65.70%.XRD analysis found that,the main components of the diatomite were quartz,cristobalite,dolomite,etc,the crystal mineral composition of activated clay and organic clay were similar,main with montmorillonite,quartz,dolomite,etc;the removal efficiency of activated clay and organic clay were matched with the pore size distribution of 1.3~7nm,diatomite contains only a small amount of macropores,but the removal efficiency was higher than that of activated clay and organic clay with large specific surface area and pore structure.In this paper,the composite material of activated carbon and activated clay were studied,the results show that,with the increase of activated carbon content in composites material,removal efficiency increased firstly and then decreased,when the activated carbon content was 75%,the removal efficiency was the highest,reaching to 98.52%.