Measurement of heavy metals by the electrical conductivity method

摘要

A laboratory investigation was conducted to evaluate the possibility of determining the equilibrium concentrations of heavy metals in soil solutions by means of the electrical conductivity method. Four types of heavy metal nitrate-soil solutions were used. Test results revealed that direct determination of equilibrium concentrations of certain ionic species in soil solutions can be inferred from the retention of heavy metals and release of exchangeable cations. This laboratory technique is based on tetermining the relationship between the ionic strengths of the heavy metal-soil solutions and their electrical conductivity. Based on this relationship, the necessary correlation can be derived to estimate the required equilibrium concentrations. The proposed technique is expected to aid in the prediction of equilibrium concentrations of some ionic species without the need for the performance of the atomic absorption spectrophotometer test.