四溴双酚A在潮土中的吸附和解吸

采用批量平衡实验方法,研究了四溴双酚A(TBBPA)在潮土中的吸附和解吸行为,并且探讨了pH值和离子强度对TBBPA吸附的影响.结果表明,TBBPA在潮土中的吸附过程可以分为快速吸附阶段(0～24 h)和慢速吸附阶段(24～48 h),其中快速吸附阶段在吸附过程中起主要作用,在48 h时吸附基本达到平衡.TBBPA在潮土中的吸附等温线呈现为非线性,其吸附行为可以很好地用Freundlich方程描述.在溶液pH值为6.0-8.0的范围内,TBBPA在潮土中的吸附量随pH值的增大而减少,当溶液pH>8.0后吸附量未表现出明显的变化趋势.离子强度也明显影响TBBPA在潮土中的吸附,随着离子强度的增加TBBPA的吸附量增加.吸附.解吸过程表明TBBPA在潮土中的解吸相对于吸附过程具有滞后性,说明潮土对TBBPA有较强的结合能力.

Sorption and Desorption Behaviors of Tetrabromobisphenol A on Fluvo-Aquic Soil

Sorption and desorption behaviors of tetrabromobisphenol A (TBBPA) on fluvo-aquic soil were investigated using batch equilibrium experiments, and the effects of pH and ionic strength on the sorption were also evaluated. The results showed that the sorption process could be divided into the rapid sorption (0-24 h) and the slow sorption (24-48 h). The rapid sorption played the main role in the sorption of TBBPA and the sorption approached equilibrium at about 48 h. The nonlinear isotherm of TBBPA on the soil was observed, and the sorption behavior could be described by Freundlich model well. The amount of TBBPA sorption decreased with the increase in solution pH within the range of pH 6.0-8.0, and did not change significantly with the increase in solution pH when pH value was greater than 8.0. The amount of TBBPA sorption increased with the increase in ionic strength. In addition, the result of sorption-desorption revealed that desorption hysteresis of TBBPA, which suggested that the fluvo-aquic soil had high affinity with TBBPA.