A New Experimental Design for Liquid-Liquid Extractive Spectrophotometric Determination of Gold(III) Using 4-(4'-Flurobenzylideneimino)-3-methyl-5-mercapto-1,2,4-triazole

A new method is presented here for liquid-liquid extractive spectrophotometric determination of gold(III). The current method is based on complexation between 4-(4'-flurobenzylideneimino)-3-methyl- 5-mercapto-1,2,4-triazole (FBIMMT) as a chromogenic reagent and gold(III) in presence of potassium iodide solution to form a yellow complex which was quantitatively extracted in chloroform at room temperature from 0.8 mol L (-1) of hydrochloric acid medium. The (1:2) [Au(III)-FBIMMT] complex in chloroform exhibited maximum absorption at & lambda; (max) 390 nm and was stable for more than 24 hrs. The values of molar absorptivity and Sandell's sensitivity of [Au(III)-FBIMMT] complex were found to be 0.98485 x 10(4) L mol (-1) cm(-1) and is 0.01858 & mu;g cm(-2) respectively. The extraction system follows Beer's law from 4.0-17.5 & mu;g mL(-1) however Ringbom's plot suggests favourable concentration range as 4.5-17.5 & mu;g mL(-1). The values of both LOD and LOQ were found to be as 0.20 and 0.78 & mu;g mL(-1) respectively.