利用好氧颗粒污泥对酸性淡黄2G溶液进行吸附脱色研究,考察了pH值、吸附剂用量、初始酸性淡黄2G的浓度、温度以及NaCl浓度对吸附过程的影响.实验结果表明,吸附过程对溶液pH值具有很高的依赖性,其最佳pH值为2.0.Temkin等温线在整个实验染料浓度范围内能够很好地描述吸附过程.吸附动力学符合准二级动力学模型.内部扩散和边界层扩散都可能影响生物吸附速率.热力学分析表明,吸附过程是一个自发的放热过程.采用FTIR分析的结果进一步揭示了颗粒污泥上官能团(如胺基、羧基和羟基等)可能是染料生物吸附的活跃结合位点.这些结果表明,好氧颗粒污泥可以作为吸附剂以去除水中的酸性淡黄2G。
Batch biosorption experiments were carried out for the removal of Acid Yellow 2G from aqueous solution using aerobic granular sludge as an effective biosorbent.The effects of solution pH value,biosorbent dosage,initial Acid Yellow 2G concentrations,NaCl concentration and temperature on the biosorption were investigated.The experimental results indicate that this process was highly dependent on pH value and the pH value of 2.0 was favorable.Temkin isotherm was more applicable for describing the biosorption equilibrium in the whole concentration range than Freundlich and Langmuir isotherms.The results of kinetics study show that the pseudo-second-order model fitted to the experimental data well.Both intraparticle diffusion and boundary layer diffusion might affect the biosorption rate.Thermodynamic studies demonstrate that the biosorption process was spontaneous and exothermic.The FTIR analysis before and after Acid Yellow 2G binding indicates that functional groups such as amine,hydroxyl,and carboxyl on the aerobic granular sludge would be the active binding sites for the biosorption.These results show that aerobic granular sludge could be effectively used as a low-cost and alternative biosorbent for the removal of Acid Yellow 2G from wastewater.