酸化污泥膨润土颗粒对染料活性翠蓝的脱色研究

Decoloration of Reactive Turquoise Blue by Acidified Sludge-Bentonite Granule

以污泥和膨润土为原料,硫酸为酸化剂制备了酸化污泥膨润土颗粒.对制得的样品进行了比表面积和SEM等表征,并用于染料活性翠蓝的脱色.考察了pH值、投加量、反应时间和反应温度的影响,并进行了方程的拟合,计算了热力学参数(ΔH0、ΔS0、ΔG)和吸附活化能Ea.结果表明,酸化污泥膨润土颗粒对活性翠蓝的吸附量随温度和初始浓度的增加而增大,吸附等温线符合Langmuir吸附模型,其吸附动力学更适于伪二级动力学方程所述规律,吸附速率大小为313 K>303 K>293 K;吸附活化能较低,为5.52 kJ.mol-1,说明吸附过程以物理吸附为主.同时ΔH0>TΔS0和ΔG>0表明整个吸附过程活化焓的影响大于活化熵,且属于非自发反应.

Using sludge as pore-forming agent, bentonite granule was acidified by sulfuric acid solution as a decolorant. The specific surface area and SEM were performed to characterize the structure of samples, and the new acidified sludge-bentonite granule was applied to the decoloration of reactive turquoise blue. The influencing factors of pH value, dosage, reaction time and reaction temperature were studied on the removal of the dyes.The important thermodynamics parameters （△H^O , △S^O, △G） and the activation energy E. were also acquired by experiment data processing. The results indicated that the adsorption isotherm fitted the isothermal adsorption equations of Langmuir better than Freundlich. The adsorption dynamics followed the law of the pseudo-second order kinetic equation,while the adsorption rate is 313 K 〉 303 K 〉 293 K.The low value of E, which is 5.52 kJ·mol^-1 shows that physical adsorption is primary. And △H^O 〉 T△S^O means that the influence of enthalpy is more remarkable than the entropy in the activation reaction. △ G 〉 O also means the chemical reactions are not spontaneous.