| 溴化十六烷基吡啶改性沸石对水中菲的吸附作用 |
| 摘要点击 2215 全文点击 1070 投稿时间：2013-05-16 修订日期：2013-07-19 |
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| 中文关键词 溴化十六烷基吡啶改性沸石 菲 吸附 单层 双层 |
| 英文关键词 cetylpyridinium bromide-modified natural zeolites phenanthrene adsorption monolayer bilayer |
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| 中文摘要 |
| 采用不同浓度的溴化十六烷基吡啶（CPB）溶液对天然沸石进行改性，制备得到了单层和双层CPB改性沸石，并通过批量吸附实验考察了这两种CPB改性沸石对水中菲的去除作用. 结果表明，单层和双层CPB改性沸石对水中菲均具备良好的吸附能力. CPB改性沸石对水中菲的去除率随吸附剂投加量的增加而增加，而CPB改性沸石对水中菲的单位吸附量随吸附剂投加量的增加而降低. CPB改性沸石对水中菲的吸附动力学过程满足准二级动力学模型. CPB改性沸石对水中菲的吸附平衡数据可以采用线性模型和Freundlich模型加以描述. CPB改性沸石对水中菲的吸附过程是一个自发和放热的过程. 单层CPB改性沸石吸附水中菲的机制主要是疏水作用，双层CPB改性沸石吸附水中菲的机制主要是有机相分配作用. 当双层CPB改性沸石的CPB负载量为单层CPB改性沸石的CPB负载量的2倍时，前者对水中菲的吸附能力略微强于后者. 以上结果表明，双层和单层CPB改性沸石均可以用于水中菲的去除；为节约成本，单层CPB改性沸石与双层 CPB改性沸石相比更适合用于水中菲的去除. |
| 英文摘要 |
| Surfactant-modified zeolites (SMZs) with different coverage types were prepared by loading of different amounts of cetylpyridinium bromide (CPB) onto natural zeolites and were used as adsorbents to remove phenanthrene from aqueous solution. The adsorption of phenanthrene from aqueous solution on monolayer and bilayer SMZs as a function of adsorbent dosage, initial phenanthrene concentration, contact time, and temperature was investigated using batch experiments. Results showed monolayer and bilayer SMZs were effective for the removal of phenanthrene from aqueous solution. The phenanthrene removal efficiency of SMZs increased with increasing adsorbent dosage, but the amount of phenanthrene adsorbed on SMZs decreased with increasing adsorbent dosage. The adsorption kinetics of phenanthrene on SMZs well followed a pseudo-second-order kinetic model. The equilibrium adsorption data of phenanthrene on SMZs at a low concentration of phenanthrene in solution could be described by the Linear equation and Freundlich equation. The main mechanism for phenanthrene adsorption onto monolayer SMZ is hydrophobic interaction, and the main mechanism for phenanthrene adsorption onto bilayer SMZ is organic partitioning. The calculated thermodynamic parameters such as Gibbs free energy change (ΔGθ), enthalpy changes (ΔHθ), and entropy change (ΔSθ) showed that the adsorption process of phenanthrene on SMZs is spontaneous and exothermic in nature. When the CPB loading amount of bilayer SMZ was twice as much as that of monolayer SMZ, the phenanthrene adsorption capacity for bilayer SMZ was slightly higher than that for monolayer SMZ. In a conclusion, both monolayer and bilayer SMZs are promising adsorbents for the removal of phenanthrene from water and wastewater, and monolayer SMZ is a more cost-effective adsorbent for phenanthrene removal than bilayer SMZ. |
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