Investigating The Effect of Extraction Solvent Kind on the preconcentration of Co(Ⅱ) By Single Drop Microextraction

Since cobalt is a natural element in the environment, the measurement of its trace amounts in water is very important. This investigation was done to develop a method which is accurate with green chemistry principles and according to simple, effective, and low cost environment for measuring cobalt. In this work, the effect of extraction solvent kind, ionic liquid 1-octyl-3-methylimidazolium hexafluorophosphate [C8 MIM][PF6] or carbon tetrachloride CCL4 was investigated to measure the trace amounts of cobalt in aqueous solution using single-drop microextraction. In microextraction, the volume of the extractor phase is a minimum amount relative to the sample volume [1]. The achieved results under optimum conditions such as pH of test solution (pH=6), amount of chelating agent (2.4% m/v), the volume of micro drop (20 μl), microextraction time (30 min) and stirring rate (300rpm) were shown in Table.The enrichment factor has been increased by using ionic liquid Because CCL4 has a higher vapor pressure than ionic liquid, an amount of it may be evaporated during the extraction process, so the repeatability in the drop volume decreases, which reduced the repeatability of the amount of extraction