松香淀粉酯对苯并芘的吸附研究

Absorption of Benzopyrene by Rosin Starch Ester

以松香淀粉酯为吸附剂对正辛烷溶液中的苯并芘进行吸附研究,分析了吸附时间、温度、苯并芘的初始浓度以及松香淀粉酯的取代度对吸附量的影响,并对吸附过程的热力学、动力学进行了分析。结果显示:提高吸附温度、苯并芘的浓度以及吸附剂的取代度均可提高吸附量;以取代度0.12的松香淀粉酯为吸附剂,在吸附时间120 min、吸附温度50℃、苯并芘的质量浓度10 mg/L条件下,对苯并芘的吸附量达20.76μg/g;该吸附过程符合Langmuir等温线模型,热力学参数ΔG^y,ΔH^y和ΔS^y表明:吸附是一个自发和吸热的过程;动力学数据分析表明松香淀粉酯对苯并芘的吸附过程符合准二级动力学模型。

The absorption of benzopyrene in octane solution by rosin starch ester was studied in this paper. Affect factors including temperature, contact time, initial concentration of benzopyrene and the degree of substitution （D,） of the rosin starch ester were investigated. The thermodynamics and kinetics of the absorption process were also studied. The results showed that increasing the absorption temperature, the benzopyrene concentration, and the D, of the adsorbent were beneficial to the adsorption process. Using rosin starch ester （Ds = 0. 12） as adsorbent, absorbing 120 min at 50 ℃ in 10 mg/L benzopyrene, the absorption capacity of benzopyrene reached to 20.76 μg/g. The measured results were fitted with the Langmuir isotherm better. Thermodynamic parameters ΔG^⊙, H^⊙and ΔS^⊙ indicated that the adsorption process was spontaneous and endothermic. Analysis of the kinetic data suggested the pseudo second order kinetic model was suitable for describing the adsorption process.