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选用活性炭作为吸附剂，研究了新型持久性有机污染物六溴环十二烷（ HBCD）在乙腈?水溶液中的吸附行为．结果表明，活性炭的投加量（0．2—2 g·L－1）、HBCD初始浓度（0—60 mg·L－1）及溶液中乙腈的比例（40％—100％）对吸附效果产生显著影响；吸附动力学分析表明活性炭对HBCD的吸附速率受颗粒内扩散过程控制；通过对比Langmuir、Freundlich和Sips模型发现Sips模型更适于描述在0．05 g·L－1的活性炭投加量， HBCD初始浓度为0—60 mg·L－1的条件下，HBCD在乙腈溶液中的吸附过程，且呈现出S型吸附等温线特点，说明在吸附剂表面可能存在较强烈的竞争吸附；通过Sips模型求得的饱和吸附容量为62 mg·g－1；在40％—100％的乙腈比例下，吸附量随着乙腈比例的提高而线性降低．在活性炭投加量为0．05 g·L－1，HBCD初始浓度为5 mg·L－1条件下，获得平衡吸附量随乙腈浓度（40％—100％）变化的回归方程，并且估算乙腈比例为0％情况下，HBCD的平衡吸附量为127．35 mg·g－1．

In this work, activated carbon ( AC ) was selected as the adsorbent to investigate the adsorption behavior of one of the new persistent organic pollutants, hexabromocyclododecane ( HBCD) , in the acetonitrile?water solution. Results showed that the adsorptions were affected significantly by the dosages of AC ( 0. 2 g·L-1—2 g·L-1 ) , initial concentrations of HBCD ( 0—60 mg·L-1 ) and proportions of acetonitrile ( 40%—100%) . The adsorption kinetics analysis showed the rate of adsorption of HBCD was controlled by the inner?sphere diffusion in AC. Langmuir, Freundlich and Sips models were used to fit the adsorption isotherm respectively. In the presence of 0.05 g·L-1 of AC and 0—60 mg·L-1 of initial concentrations of HBCD, the Sips model can better describe the adsorption process in acetonitrile solution which has the S type isotherm and implied the existence of strong competition of adsorption on the surface of AC. The saturated adsorption capacity is 62 mg·g-1 via Sips model. The adsorption capacity decreased linearly as the proportion of acetonitrile over the range of 40% to 100%. The regression equation of equilibrium adsorption capacity that varies with acetonitrile concentrations ( 40—100%) was obtained in the presence of 0?05 g·L-1 of AC and 5 mg·L-1 of initial concentration of HBCD, and the equilibrium adsorption capacity for HBCD was speculated as 127. 35 mg·g-1 under the acetonitrile proportion of 0%. This work provides the basis for removing HBCD from water by AC.