水动力与表面活性剂协同作用对双酚A在沉积物上吸附的影响

Influence of the presence of hydrodynamics and surfactant on the adsorption of bisphenol A to sediment

选择太湖梅梁湾的表层沉积物作为实验对象,研究了水动力与表面活性剂协同作用下,双酚A吸附行为的变化特征.结果表明,当CTMAB(十六烷基三甲基溴化铵)浓度在1.0倍临界胶束浓度(CMC)以下时,切应力的改变对双酚A在沉积物上的吸附量基本无影响;其吸附量随CTMAB浓度的增大而增大,0.1倍CMC、0.5倍CMC和1.0倍CMC的CTMAB条件下,双酚A的吸附量较0 CMC分别增大了0.18倍、0.54倍和0.62倍;相对于Freundich模型,其吸附等温线更符合线性模型.当CTMAB浓度高于CMC时,双酚A在沉积物上的吸附量和吸附平衡时间均随切应力的增加而减小,在切应力和低浓度CTMAB共同作用时,以切应力促进吸附平衡作用为主;而当切应力和高浓度CTMAB共同作用时,以CTMAB的作用为主.水动力和CTMAB共同作用下的双酚A的吸附过程满足准二级吸附动力学方程.

Variation of BPA adsorption on suspended solids under hydrodynamics and surfactant ,was investigated, using sediments from Meiliang Bay. The results showed that when CTMAB concentration was lower than the critical micelle concentration （ CMC）, the change of hydrodynamic had no influence on the amount of BPA adsorption. Adsorption increased with the increasing CTMAB concentration, when 0.l times CMC, 0.5 times CMC, 1.0 times CMC CTMAB added, the adsorption quantity of BPA were increased 0.1B times, 0.54 times and 0.62 times respectively compared with 0 CMC. The adsorption isotherm transferred from a linear programming model to non-linear. When CTMAB concentration was higher than CMC, adsorption decreased with the increasing CTMAB concentration and hydrodynamic. In the combination of hydrodynamic and low concentration of CTMAB, shear stress was the major stress. But when in the combination of hydrodynamic aM high concentration of CTMAB, CTMAB based. The pesudo-second-order kinetics model could well characterize the BPA adsorption process with different CTMAB concentrations and hydrodynamics.