The Research On Removal Of Phenol From Water On Hydrotalcite-like Compounds

Shanxi province is an important coal production base in China,the coal industry is an important pillar industry in Shanxi Province,the coking industry is an important part of the coal industry.The coking production process will produce a large amount of wastewater without treatment into the environment will cause pollution of soil and groundwater;advanced coal gasification technology in underground coal gasification process will generate a threat to the safety of groundwater organic pollutants.Phenolic compounds are common organic pollutants in groundwater,because they have the effect of protoplast toxicity,and the concentration of pH and phenol in waste water and other factors,the biological treatment effect is often poor.Shanxi Province,more than drinking water sources for groundwater exploitation,there are more than the detection of phenol.Therefore,it is important to find an efficient way to remove the pollution of phenol to improve the water quality of our province and to ensure the health of the residents.In this paper,the Mg/Al/Fe type of like compounds were prepared by co precipitation method at different calcination temperatures,and the structure of adsorption materials were characterized by XRD,FT-IR and SEM.With high toxic phenol as the object,focus on the factors of adsorption of phenol Mg/Al/Fe hydrotalcite and influence;the adsorption process was analyzed,the adsorption mechanism is discussed;and the other 2 kinds of selected adsorption experiments of hydrotalcite-like materials of phenol,the optimal phenol adsorption materialThe main methods and conclusions are as follows:1?The co-precipitation method synthesis of Mg/Al/Fe hydrotalcite like materials and their calcined products by XRD,FT-IR,SEM etc.The results show that the synthesis of materials with layered structure of hydrotalcite like materials typical of its structure,clear and complete.After calcination,the material loses the interlayer anions and the water,which can be replaced by the memory effect and the anion,which may provide the possibility for the adsorption of phenol.Mg/Al/Fe hydrotalcite phenol adsorption experiment results showed that the Mg/Al/Fe hydrotalcite like materials can be in the temperature range of 25-40?,play a role;adsorbent dosage on the removal rate of phenol has no obvious change;the reaction time is 40 min has basically reached saturation adsorption state.The kinetic experiments showed that the dosage of 0.1mg/L in accordance with the first-order kinetic equation,the rate constant and the equilibrium adsorption capacity is 0.0295min-1 and 8.51mg/g respectively;the dosage of 0.5mg/L and 1mg/L were pseudo two order kinetics equation,and the equilibrium adsorption rate constant was 0.0029L/(mg.min),0.0032L/(mg.min)and 10.90mg/g,11.04mg/g respectively.Isothermal adsorption isotherm model was satisfied with Langmuir adsorption isotherm model.The adsorption process showed that the adsorption process was monolayer adsorption,the presence of chemical adsorption,the adsorption was preferential adsorption.The presence of coexisting ions has an inhibitory effect on phenol.The adsorption of sulfate,fluoride and phenol in the first order is:sulfate ion,fluorine ion,phenol,which indicate that the charge ionic radius ratio(Z/r)is greater in the adsorption process of the class,the greater the affinity.2?XRD characterization results of Mg/Fe like compounds prepared by co precipitation method showed that the material has a typical layered structure,and the structure was clear and complete.The results showed that the removalrate of phenol by pH was not affected by 40 min,and the temperature was increased first and then decreased.The adsorption efficiency increased with the increase of the adsorbent dosage,and the adsorption efficiency was almost complete.The adsorption kinetics showed that the dosage of 0.1mg/L,0.5mg/L and 1.0mg/L could meet the first-order kinetic equation,the rate constants obtained were 0.0220min-1,0.0217min-1 and 0.0254min-1,the adsorption capacity of adsorption equilibrium for 8.12mg/g,9.30mg/g and 9.53mg/g respectively.3?Using soluble starch Mg/Al hydrotalcite like compounds dispersed,XRD characterization results show that Mg/Al hydrotalcite like compounds with starch than conventional Mg/Al hydrotalcite peak sharpness decreases,but the size is more uniform.The adsorption results show that without calcination,Mg/Al hydrotalcite like compounds dispersed after the starch can be effectively adsorbed phenol;adsorption efficiency of phenol no response to p H;the best adsorption temperature is 30?;starch dosage concentration of 10g/L,adsorbent dosage was 1mg/L.The adsorption kinetics showed that the dosage of 0.1mg/L and 0.5mg/L could meet the first-order kinetic equation,and the equilibrium adsorption rate constants obtained were 0.0223min-1,0.0233min-1 and 8.45mg/g,9.39mg/g respectively;dosage of 1mg pseudo two order kinetic equations,the rate constants and the equilibrium adsorption amount was 0.0028L/(mg.min)and 11.19mg/g respectively.4?Three kinds of adsorption materials all have a good effect on the adsorption of phenol,but the adsorption effect of Mg/Al/Fe compound on phenol is better than that of the other two kinds of materials.It is effective to play a role in the temperature range is relatively wide,can be in the range of25-40? of adsorption of phenol,and the adsorption efficiency are more than90%.In addition,Mg/Al/Fe dosage can play a better role,only the amount of investment is 0.5mg/L,the adsorption efficiency can reach 97%.