Spectrophotometric Determination of Cerium(III) in Some Industrial and Plant Samples Using New Synthesized Azo-dye Reagent: Synthesis and Characterization

NEW spectrophotometric method was proposed for the rapid and accurate determination of Ce(III) using a new synthesized sulfacetamide azo-dye reagent [N-(4-((2,3-dihydroy-5-(3,5,7-trihydroxy-4-oxo-4H-chromen-2-yl)phenyl)diazenyl) phenylsulfonyl)acetamide] [DTPPA]. The reagent was characterized by TR, (HNMR)-H-1 and mass spectra. The developed method was based on the reaction of Ce(III) with DTPPA reagent to form brown colored complex in an alkaline medium using borate buffer at pH = 9 with absorption maximum at 560 urn. The method was enhanced by the use of cationic surfactant of cetylpyridinium bromide (CPB). Different factors affecting the fonnation and stability of the complex such as reagent concentration, time, temperature, solvents and order of addition were also studied. The composition of the complex was found 1:2 (metal: ligand) by both Job's and molar ratio methods. The stability constant of the complex was calculated to be 3.387 x10(6). Beer's law was obeyed in the concentration range of 5.0-100 mu g mL(-1) of Ce(III) with molar absorpitivity and Sandell's sensitivity 1.020 x10(4) L mol(-1) cm(-2) and 0.01373 mu g cm(-2), respectively. The proposed method was applied for the determination of micro-amounts of Ce(M) in some industrial and plant samples. The Ce(III) complex was also prepared in the solid state.