Adsorption Characteristics Of Three Types Of Dye By Fly Ash In Water

With the development of society and the improvement of people’s living standard,the textile printing and dyeing products needs is more and more big, the quality andquantity in all be improved a lot. Textile production in the process to have a lot ofprinting and dyeing wastewater is discharged, the printing and dyeing wastewatertreatment such as not pass through direct emissions of water, causing serious pollutionof environment.Coal-fired power plants produce the coal fly ash emissions is China’s industrialsolid waste pollution sources of the biggest single, by the year2010, our country actualcomprehensive utilization ratio of fly ash is only30%, a large number of fly ash havenot been effectively, the pollution of the environment.As a kind of porous solid particles waste, in many areas including construction,road, agriculture, water treatment and chemical industry has high utilization value,because of the fly ash porous, but also has certain activity, make in the wastewater byadsorption field gradually get attention.Aiming at the resource utilization of Fly ash generated by power plant, and solvingthe increasingly serious problem of dye wastewater treatment, this paper uses waste Flyash from coal power plant as sorbent dosage to research the removal process of Fly ashon the dye OrangeⅡ, Neutral pink BL and Fuchsin basic of different types. It is showedthat: the adsorption kinetics of Fly ash on the three different dye in the water follow thefirst order reaction model dC/dt=-k（C-C_e）; with the major addition of Fly ash, it hasweak influence on the Fly ash adsorption capacity and removal effect under the samedye concentration conditions; the isothermal adsorption of Fly ash on the three dye obeyFreundlich model, in which the model parameters a and b of absorbing cationic dyeOrangeⅡvary0.48⁰.78mg·g^-1and0.23⁰.39, with pH=4¹2, indicating that theparameter a and b from the absorption of Fly ash on the cationic dye OrangeⅡ havefine linear relationship; the model parameter a of the absorbing neutral dye Neutral pinkBL varies from0.45⁰.53mg·g^-1, while b varies from0.14⁰.19, showing good linearrelationship if pH in in the range4¹0; Dealing with the absorption of anionic dyeFuchsin basic, its absorption is very weak when pH=2, while a and b has good linearrelationship if pH=4,6,10,12. The influence of temperature on the absorption of three isquite different. With the regards to OrangeⅡ dye system, lower temperature corresponds to the higher Fly ash particles adsorption capacity. The temperature at25℃has obvious adverse effect on the adsorption. Compared with the diffusion step ofdye adsorption, adsorption is the key contrl step to the whole process. Towards theNeutral pink BL and Fuchsin basic dye system, higher temperature corresponds tohigher Fly ash particles adsorption capacity.Compared with the diffusion step of dyeadsorption, adsorption is the key contrl step to the whole process. After the temperatureup to20℃, continuous rise of temperature, the increase amplitude of Fly ash adsorptionproperty on Neutral pink BL fade gradually, while its adsorption property on Fuchsinbasic exhibits Elevated law. With the increase of ionic strength, the adsorption propertyof Fly ash on the three dye rise. For OrangeⅡ at low ionic intensity, the parameter a ofFreundlich model is affected greatly by the ionic intensity while the same effect ofparameter b is small, and the parameter a of Freundlich model is affected weakly by theionic intensity while the same effect of parameter b is great. With regard to Neutral pinkBL, the variation of parameter a is relatively small if the ionic intensity is at0⁰.5mol·L^-1, showing weak influence of ionic intensity on the adsorption system;Parameter a augments rapidly with the increase of ionic intensity if its value is at0.5¹.5mol·L^-1, and parameter b is considerable steady, when the ionic strengthincreases to a certain concentration, its affectation on the adsorption system will begradually weakened.For basic fuchsin, when the ionic strength increases0⁰.5mol·L^-1,value a of model parameters increases rapidly, and value a began to decrease when ionformer continues to be increased, the trend is gentle.