Abstract:A new non-organic solvents extraction catalytic spectrophotometric method for the determination of trace amounts of manganese was studied.The method is based on the manganese(Ⅱ) catalyzing hydrogen peroxide to oxidate of eriochrome black T in hydroxide-ammonium chloride buffer medium.The reaction time and the degree of indicating reaction are controlled by non-organic solvents extraction equilibrium using polyethylene glycol-2000.The absorbance of polyethylene glycol-2000 phase is measured at 539 nm in weak acidic medium.The calibration graph is linear for 0.008 0-0.55 μg· mL-1 Mn(Ⅱ), and the detection limit is 3.0×10-9 g·L-1.The method can be applied to the determination of trace manganese in tea and aluminum alloy with satisfactory results.
Key words:Manganese;Non-organic solvents extraction;Catalytic spectrophotometry;Eriochrome black T;Polyethylene glycol-2000
[1] DENG Fan-zheng, SHI Ying, LIU Qing(邓凡政,石 影,刘 庆).Chinese J.Anal.Chem.(分析化学),1995, 23(7): 832. [2] LI Bu-hai, ZOU Qun, SUN Xiao-mei(李步海,邹 群,孙小梅).Chinese J.Anal.Chem.(分析化学),1998, 26(8): 1022. [3] DENG Fan-zheng, SHI Ying, MA Li-hua(邓凡政,石 影,马丽华).Chemistry Bulletin(化学通报),1995,(12): 22. [4] SUN Deng-ming, ZHU Qing-ren, LI Xiao-yan(孙登明,朱庆仁,李晓艳).Spectroscopy and Spectral Analysis(光谱学与光谱分析),2003,23(6): 1157. [5] SUN Deng-ming, JI Fang(孙登明,计 芳).Spectroscopy and Spectral Analysis(光谱学与光谱分析),2003,23(2): 351. [6] SUN Deng-ming(孙登明).Chinese J.Anal.Chem.(分析化学),1999,27(7): 821. [7] SUN Deng-ming, GAO Qiong, GU Ling, et al(孙登明,高 琼,古 玲,等).J.Huaibei Coal Industry Teachers College(Natural Science Edition)(淮北煤炭师范院学报·自然科学版),1991,12(2): 42.