Separation and determination of mercury from nail and hair in petrochemical workers based on silver carbon nanotubes by microwave-assisted headspace sorbent trap

In this work, the occupational analytical chemistry was developed for determination of chronic exposure of mercury in nail and hair in petrochemical workers (Age: ۳۰-۵۰, Men). By experimental procedure, ۱۰۰ mg of hair and nail of workers was prepared by washing / grinding and then the powder was dried in oven for ۲۰ min at ۹۵oC. ۲۰ mg of hair or nail samples added to reagents (HNO۳/H۲O۲; ۵:۱) in polyethylene tube (PET) of microwave digestion and the mercury in resulting solution was removed with silver nanoparticles pasted on multi-walled carbon nanotubes (Ag-MWCNTs) which were placed in head space of separator. After microwave digestion for ۲۵ min, the mercury vapor was removed by Ag-MWCNTs as the headspace sorbent trap (HSST) under hood conditions. Finally, the mercury in sorbent was online determined by cold vapor atomic absorption spectrometry (CV-AAS) after heat process at ۲۵۰oC in presence of Ar gas. The capacity adsorptions of Ag- MWCNTs and MWCNTs for mercury removal from air were obtained ۲۰۵.۴ mg g-۱ and ۶۳.۷ mg g-۱, respectively. The mean of mercury in nail and hair in workers and healthy peoples was achieved (۱۵.۲±۳.۷ μg g-۱; ۱۱.۶± ۲.۶ μg g-۱) and (۰.۱۶±۰.۰۵ μg g-۱; ۰.۲۴± ۰.۰۳ μg g-۱), respectively (RSD<۵%). The validation of method was done by certified reference material (CRM).

کلیدواژه ها:

Mercury ، Nail and Hair ، Silver multi-walled carbon nanotubes ، Microwave-assisted headspace removal