Chen Chih-Yu, Chung Ying-Chien
Department of Tourism, Hsing Wu College, Taipei, Taiwan, Republic of China.
J Environ Sci Health A Tox Hazard Subst Environ Eng. 2006;41(2):235-48. doi: 10.1080/10934520500354573.
Removal of phthalate esters (PAEs) by chitosan bead in aqueous solution was studied. The adsorption isotherms of PAEs by chitosan bead were well described by Freundlich isotherm equations. Results of kinetic experiments indicated that diheptyl phthalate (DHpP) had the highest adsorption capacity (1.52 mg/g) among six PAEs in our research. PAE adsorption efficiency by chitosan bead was examined in both batch and continuous systems, and DHpP attained 74.9% recovery efficiency from chitosan bead by shaking with an equal volume mixture of methanol and water. The recovered chitosan bead was reusable as an adsorbent. The influences of temperature, pH, Ca+2, and NaCl on PAE adsorption were also evaluated to determine performance in different water environments (e.g., groundwater, surface water, and sea water). The results showed that PAE adsorption decreased as temperature increased. From pH experiments it appeared that pH 8.0 was optimal for adsorption. The effect of Ca+2 showed that adsorption efficiency did not change by increasing the concentrations of Ca+2 until 400 mg/L. NaCl coexistence showed an insignificant effect on PAE adsorption. Furthermore, the chitosan bead was also applied to treating the discharge of a plastics plant, and the treatment results resembled those of a laboratory continuous system. This is the first report to use chitosan bead as an adsorbent to adsorb phthalate esters from aqueous solution. These results indicate that the application of chitosan bead is feasible in the aqueous environments of Taiwan.
研究了壳聚糖珠在水溶液中对邻苯二甲酸酯（PAEs）的去除效果。壳聚糖珠对PAEs的吸附等温线能很好地用Freundlich等温方程描述。动力学实验结果表明，在我们研究的六种PAEs中，邻苯二甲酸二庚酯（DHpP）的吸附容量最高（1.52 mg/g）。在分批和连续系统中都考察了壳聚糖珠对PAE的吸附效率，通过与等体积的甲醇和水的混合物振荡，DHpP从壳聚糖珠上的回收效率达到了74.9%。回收的壳聚糖珠可作为吸附剂重复使用。还评估了温度、pH值、Ca²⁺和NaCl对PAE吸附的影响，以确定在不同水环境（如地下水、地表水和海水）中的性能。结果表明，PAE的吸附量随温度升高而降低。从pH实验来看，pH 8.0是最佳吸附pH值。Ca²⁺的影响表明，在Ca²⁺浓度增加到400 mg/L之前，吸附效率没有变化。NaCl的共存对PAE吸附的影响不显著。此外，壳聚糖珠还应用于处理塑料厂的排放物，处理结果与实验室连续系统的结果相似。这是首次报道使用壳聚糖珠作为吸附剂从水溶液中吸附邻苯二甲酸酯。这些结果表明，壳聚糖珠在台湾的水环境中应用是可行的。
