Determination of Nickel in Alloys and Plant Leaves with Salicylaldehyde 3-Oxobutanoylhydrazone by Spectrophotometry

A simple and highly sensitive reagent of salicylaldehyde 3-oxobutanoylhydrazone (salicylaldehyde acetoacetic acid hydrazone, SAAH) was synthesized and studied for the spectrophotometric determination of nickel in detail. In the pH range 6, which greatly increased the selectivity, nickel reacted with SAAH to form a 1:1 yellow complex, having a sensitive absorption peak at 405 nm. Under the optimal conditions, Beer’s law was obeyed over the range from 0.0117 to 0.1174 µg cm–3. The apparent molar absorptivity was 3.025 × 105 dm3 mol–1 cm–1. The detection limit and the variation coefficient were found to be 1.752 ng cm–3 and 1.0%, respectively. The method has been applied to the quantitative determination of nickel in different alloys and leaves.