【Abstract】 A novel method of extraction spectrophotometric determination of nickel in aqueous two-phase system(ATPS) formed by polyethylene glycol-2000(PEG) and(NH4)2SO4 was developed.The effects of solution acidity,the dosage of xylenol orange(XO),salt and elimination of interference form other coexistence sulstances on the extraction determination of nickel were studied.In PEG-(NH4)2SO4 aqueous two-phase system of pH 3.0-5.0,the complex formed by xylenol orange and Ni2+ had high absorbance with the maximum absorption of 477nm.Beer’s law was obeyed in the range of 0-5.0μg/mL for Ni2+ with the apparent molar absorptivity of 5.14×104 L·mol-1·cm-1.The complex ratio of xylenol orange and Ni2+3∶1.The method has been applied to the determination of nickel in standard aluminium alloy and the results were in agreement with the certified values.更多还原