Sorption of Phenanthrene on Different Particle Size Fractions of Inter-tidal Zone Sediments from Bohai Bay
Batch experiments were done to investigate the sorption of phenanthrene on different size fractions of inter-tidal zone sediments from Bohai Bay,and relationships between sorption parameters and organic matter properties were discussed.Results indicated that TOC contents of different particle size fractions were clay,sand and silt.BC contents for Qikou sediment was according with TOC contents,with the highest BC contents for Dagukou and Lujuhe sediments presented in the sand fraction,and the lowest BC contents in the silt fraction.Both C/N and BC/TOC values increased with increasing size fractions for all sediments.Data of phenanthrene sorption on different size fractions of sediments could be fitted with linear and Freundlich model.Trends of KD and KF values in sediment fractions were according with TOC and BC contents respectively.KFOC values increased with increasing particles size fractions for Dagukou and Qikou sediments,and the lowest KFOC value was presented in the silt fraction for Lujuhe sediment.There were significantly positive correlations between KD value and TOC,BC,TN contents or between KF value and BC contents or between KFOC and C/N,BC/TOC values.Therefore,the sorption of phenanthrene on different particle size fraction was controlled by TOC contents,but the sorption capacity was determined by BC content.The input of organic matter by anthropogenic sources including coal and BC production was likely to cause higher sorption capacity of phenanthrene in large size fraction.