Determination of Heavy Metal Elements in Biogas Slurry with Inductively Coupled Plasma Mass Spectrometry(ICP-MS)

Coupled plasma mass spectrometry was performed to determine heavy metal elements in a biogas slurry which had been pretreated with wet digestion.The interferential effect was corrected by the in-line addition of internal standards.Satisfactory linearity of working curves of six elements(Pb,Cd,Cr,As,Hg and Ni) was obtained,their correlation coefficients being over 0.999 3,the determination limit,the RSD and the recoveries of the analytes in the samples being in the range of 0.90-67.0 ng/L,0.79%-2.51% and 93.4-101.2%,respectively.Their average concentrations in the biogas slurry were in the order of NiAsCrPbCdHg.