摘要
基于长江、嘉陵江重庆主城段不同粒径表层沉积物样品,进行了粘土矿物(高岭石、蒙脱石)掺混前后对典型多环芳烃荧蒽的吸附特性研究,试验结果表明,荧蒽的吸附能力与表层沉积物粒径大小具有一定的相关性;沉积物粒径越小,其吸附能力相对越强.不同粒径的表层沉积物对荧蒽的等温吸附曲线表明,对于相同的液相平衡浓度,固相吸附量大小依次为320目>240目>120目.沉积物样品中粘土矿物的掺混可显著增强其对荧蒽的吸附能力,且蒙脱石优于高岭石,这是由于不同粘土矿物晶型构成存在差异.沉积物样品对荧蒽分配特性的分析结果表明,掺混样品对荧蒽吸附的土壤/沉积物吸着系数值(K_(oc))较根据化合物水/辛醇分配系数(K_(ow))的预测计算值高,荧蒽在沉积物复合体有机相上分配的同时,也有相当一部分吸附到无机矿物的表面,无机矿物对于沉积物中荧蒽的吸附作用不容忽视.
Sorption and partition properties of fluoranthene （Fluo） on surface sediments with different grain sizes, as well as the effect of clay minerals（Kaolinite and Montmorillonite）on its sorption behaviors were studied. The sediment samples were obtained from several sections of Chongqing downtown area in Yangtze River and Jialing River. The experimental results showed that there exists negative correlation between the sorption ability and grain sizes of sediment. The smaller the sediment size was, the stronger the sorption capacity would be. According to adsorption isotherm of Fluo for sediments with different particle-sizes, the sorption capacity was 320 mesh〉 240 mesh〉 120 mesh at the same equilibrium concentration. The blend of clay minerals in sediment samples significantly enhanced their adsorption properties for fluo. Meanwhile montmorillonite gave a better performance than kaolinite owing to the difference of crystal structure for minerals. Partition properties tests showed that the actual Kac values were higher than those predicted from Kaw values, which indicated that a considerable portion of fluo is adsorbed onto inorganic mineral surfaces while distributing in organic phase. And the adsorption effects of the inorganic minerals for fluo could not be neglected.
出处
《四川大学学报（自然科学版）》
CAS
CSCD
北大核心
2012年第5期1096-1100,共5页
Journal of Sichuan University(Natural Science Edition)
基金
国家自然科学基金项目(41101457)
中央高校专项基金(CDJZR11 2100 06)
关键词
粘土矿物
荧蒽
表层沉积物
吸附特性
clay mineral, fluoranthene, surface sediment, sorption behavior
