Abstract：In buffer solution of citric acid monohydrate-disodium hydrogen phosphate at pH 5-7.5, cobalt water samples were chelated by 1-(2-pyridylazo)-2-naphthol(PAN) to form Co-PAN. After water-bath at 66 ℃ for two hours, Co-PAN is extracted into Triton X-100 nonionic surfactant phase and separated from bulk water. Extracted cobalt content was measured by graphite furnace atomic absorption spectrometry. The surfactant phase separated was treated with 0.5% HNO3-0.1% Pd(NO3)2 to remove background interference at 1 200 ℃ temperature. The pre-concentration of cobalt in water samples permitted the detection of 0.003 μg·L-1(10σ) with the enhancement factor of 100. The recoveries were 90.5%-106%. The proposed method was applied to the determination of cobalt in water samples and satisfactory results were obtained.
Key words：Cloud point extraction;Cobalt;Water;GFAAS
张 源，罗文鸿*，李 慧 . 浊点萃取-石墨炉原子吸收法测定水样中痕量钴的研究[J]. 光谱学与光谱分析, 2005, 25(04): 576-578.
ZHANG Yuan, LUO Wen-hong*, LI Hui . Determination of Trace Cobalt in Water Samples by Graphite Furnace Atomic Absorption Spectrometry after Cloud Point . SPECTROSCOPY AND SPECTRAL ANALYSIS, 2005, 25(04): 576-578.
[1] HUA Lei，ZHU Hong-tao(华 蕾，朱洪涛). Journal of Hebei University(Science)(河北大学学报·自然科学版)，1998, 18(1)：61. [2] Goswami A, Singh A K. Anal. Bioanal. Chem., 2002, 374(3)：554. [3] WANG Ai-xia, ZHANG Hong, ZHANG Zhuo-yong, Lü Jin-ju, CUI Xiao-yan(王爱霞，张 红，张卓勇，吕金菊，崔笑岩). Spectroscopy and Spectral Analysis(光谱学与光谱分析)，2003，23(4)：785. [4] Benkhedda K, Infante H G，Ivanova E et al. Fresenius J. Anal. Chem., 2000, 368(2-3): 288. [5] MA Yue，YAN Zhe，HUANG Jun-xiong(马 岳，阎 哲，黄骏雄). Progress in Chemistry(化学进展)，2001，13(1)：25.
