With microplastics as the vector,the enriching capability of microplastics towards lead ions was studied.Firstly,the lead ions absorbed on microplastics were desorbed with 2% nitric acid by ultrasound,and then the lead content was determined by inductively coupled plasma mass spectrometry(ICP-MS) to investigate the adsorption ability.In the present study,the microplastics material,adsorption time,particle size,ion concentration,method selectivity and coexisting ions were investigated to analyze the adsorption characteristics of lead on microplastics.The results showed that different materials of microplastics had different adsorption abilities to lead.Polyvinyl chloride (PVC) and polypropylene (PP) had the best adsorption abilities among all the tested materials,with adsorbances of 1.32 μg/g and 0.63 μg/g,respectively.The adsorbance of microplastics to lead reduced with the increase of the particle size.With the increase of the adsorption time and lead ion concentration,the adsorption efficiency of microplastics to lead increased first and then decreased.The results of coexisting ions experiments indicated that adsorption capacities of different microplastics were influenced by the coexisting ions.There was a competitive adsorption phenomenon when copper and lead coexisted.In this study,the adsorption characteristics of microplastics to lead ion were studied,which could provide a theoretical basis for the further research on enrichment of microplastics to the heavy metals and their environmental behavior in marine environment.
关键词
微塑料聚丙烯吸附铅离子电感耦合等离子体质谱(ICP-MS)
Keywords
microplasticspolypropyleneadsorptionlead ionsinductively coupled plasma mass spectrometry(ICP-MS)