| Recent years, the water supply safety is threatened by pollution accident existing in source water especially the organic matters pollution. The accidents have caused serious damage of people's health and property. Exposure to ethylbenzene in humans results in throat irritation and chest constriction, irritation of the eyes,even it can affect lungs, liver and kidneys. As an important raw material of chemical production, ethylbenzene Its main use in the petrochemical industry as a production intermediate of styrene. also widly existed in the lacquer and pesticides in the wastewater discharges, which would add the risk of sudden pollution in the soure water of a city.At present, one of the effective measures to deal with the sudden pollution of ethylbenzene was to add powdered activated carbon (PAC) to the soure water.In this paper, coal made carbon and wood made carbon was used to adsorption ethylbenzene, PAC surface physical and chemical properties also been analysis, the adsorption kinetics and isotherms of ethylbenzene were conducted in water with PAC. The optimal mathematical models were selected through the models used to fit the experiment data. the effect of pH, temperature, ionic strength, NOM on ethylbenzene adsorption onto PAC was studied. The research on the removal of ethylbenzene treated by PAC adsorption associated with coagulation was conducted. Results showed that two kinds of PAC surface groups,as carboxyl groups, lactones groups, phenolic hydroxyl groupnd and base group difference of -6.83% 4.01%, 3.01% and 0%, respectively. the zero charge points was 8.02 (wood) and 8.22 (coal). two kinds of PAC have large surface area of 1125.23 m~2/g (coal) and 1210.21m2/g (wood), respectively. Micro pore surface area of wood made PAC are larger than the coal made PAC, particle size of PAC in the water mainly less 10μm. when Initial concentration of ethylbenzene is 4.2mg/L ,The rate of adsorption of ethylbenzene on PAC in water was so rapid that the adsorption capacities were more than 90%(wood) and 80% (coal) of that of equilibrium at the time of 5min respectively. 97% (wood)and 94%(coal) adsorption capacities in 30min,After 2 hours, the adsorption process tends to reaching equilibrium. The experimental adsorption data showed good correlation with pseudo-second-order kinetics equation, which had a satisfied description of the process of ethylbenzene adsorption on PAC within 2 hours.The adsorption isotherm can be fitted well with Freundlich model. PAC has a large adsorption capacity of ethylbenzene when the pH value of water was closed to the isoelectric point of itself ,The adsorption of ethylbenzene on PAC was an exothermic process. low temperature can conducive the adsorption capacity of PAC,this process is physical adsorption. high ionic strength can enhance adsorption capacity of coal made carbon . NOM existed in water has a negative effect on the adsorption kinetic of ethylbenzene on coal made PAC. Of the combined effect of PAC adsorption and coagulation-sedimentation, PAC adsorption was the key link for the removal of ethylbenzene while the coagulation-sedimentation contributed to the removal of PAC and other suspended solids in raw water.removal of PAC , best coagulant to removal of the PAC is polyaluminum, and the best dosage is 5mg /L(measure by Al2O3).In all, dosing PAC to raw water was an effect emergency treatment technology to deal with the sudden pollution caused by ethylbenzene for water plants.
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