Determination of nickel and selenium by direct injection enthalpimetry

The construction of a simple thermometric titrator is described. The titrator has been used in a direct injection enthalpimetric procedure to determine nickel and selenium with precisions of 1.0 and 0.3% respectively at a concentration of 10(-2M). The titrant was quinoxaline-2,3-dithiol (disodium salt). The thermometric procedure is shown to be successful in the determination of selenium in contrast to an absorptiometric method using the same reagent.