TiO_2@酵母微球吸附废水中的荧光增白剂-VBL及再生研究

Adsorption of fluorescent whitening agent-VBL in the waste water by TiO_2@yeast microspheres and regeneration research

采用静电自组装的方法制备出具有草莓结构的TiO2@酵母微球作为吸附材料,对阴离子型荧光增白剂-VBL(FWA-VBL)废水进行吸附研究,考察了溶液p H、溶液初始浓度和TiO2@酵母投加量对吸附效果的影响.结果表明,酸性条件有利于TiO2@酵母微球对FWA-VBL的吸附,平衡吸附量随着溶液初始浓度的增加而增加,随着TiO2@酵母微球投加量的增加而减小.TiO2@酵母对FWA-VBL的吸附行为更加符合Langmuir等温模型,在温度为323.15K下最大吸附量为167.50mg/g;吸附动力学符合二级动力学方程;热力学参数表明吸附过程是自发的吸热过程.归因于光催化-吸附耦合效应,TiO2@酵母微球展现出了良好的原位再生能力.H2O2的添加有助于提高TiO2@酵母微球的再生性能.

TiO2@yeast microspheres with a unique raspberry-like structure were prepared through electrostatic- interaction-driven self-assembly heterocoagulation. The obtained TiO2@yeast microspheres were subsequently used as adsorbents for removal of anionic fluorescent whitening agent-VBL （FWA-VBL） from aqueous solutions. The adsorption characteristics were determined by investigating factors such as pH, initial concentration and adsorbent dose, respectively. The adsorption equilibrium data were best represented by the Langrnuir isotherm model, and the maximum adsorption capacity of the sorbent was 167.50mg/g at the temperature of 323.15K. The adsorption kinetic was found to follow the pseudo-second-order kinetic model. Thermodynamic parameters indicated that the adsorption was a spontaneous and endothermic process. Due to the coupling effects of photo-catalytic function and adsorption, TiOR@yeast microspheres show desired in-situ regeneration. Additionally, adding 1-1202 could improve the regeneration performance of TiO2@yeast microspheres.