摘要：

The chemical speciation of heavy metals in soil can better indicate their mobility and biological toxicity. The traditional method of chemical speciation of heavy metals (BCR method) is affected by its long extraction time. The traditional BCR method was optimized by vortex extraction. The chemical speciation of Cu, Zn, Pb, Cd, Ni and Cr in soil has been tested. Rotationl speed and extraction time of vortex extraction, precision and and accuracy have been studied. The results indicate that the vortex extraction effect is good, when the vortex rotation is 2 500 r/min, the vortex extraction time of acid exchangeable form is 10 minutes, the vortex extraction time of reducible form is 10 minutes, the vortex extraction time of oxidizable form is 5 minutes. The applicability of the method was verified by using soil reference materials. The detection limit of six elements is 0.4—32 μg/kg. The measured values are within the range of standard values. The relative standard deviation is 0.3%—5.5%. The utilization of vortex extraction-modified BCR procedure has fast analysis speed and high sensitivity, it can meet the detection requirements for simultaneous determination of chemical speciation of various metal elements in soil.

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