Improved determination of mercury complex with Thiomicher's ketone by beta-correction spectrophotometry

Determination of the mercury complex formed with Thiomicher's ketone (TMK) was improved by beta-correction spectrophotometry in the presence of a nonionic surfactant at pH 5. The complex formed was Hg(TMK)2, and its true molar absorptivity is reported for the first time: epsilon Hg(TMK)2(560) = 1.04 x 10(5) L/mol.cm. In addition, the stability constant of Hg(TMK)2 was equal to 3.64 x 10(10) at an ion strength of 0.01 at 20 degrees C. Results from analyses of wastewater samples showed that the relative standard deviations were < or = 8.3%, and the recoveries of mercury ranged from 90 to 110%.