extraction methods, large amounts of organic solvents are wasted. Therefore, these methods are always necessary to examine about detailed recovery of the purpose elements. The electrolytic dissolution of an Al alloy and determination
of metals by inductively coupled plasma-optical emission spectrometry (ICP-OES) was reported [5]. This method is relatively fast (about 30 min). However, the limit of detection (LOD) of Cu is high (0.047_gml−1).As the direct method for a solid sample, glow discharge-mass spectrometry is possible to high sensitive measurement [6,7]. However, it is necessary to obtain a relative sensitivity factor for each sample to get reliable date. The microchip method has attracted much attention, because It enables chemical process to miniaturize. The microchip has been used for various purposes such as chemical synthesis, immunoassay, etc [8,9]. Recently microchip method has various advantages in the analytical field, such as speed, easiness for automation, and small amounts of sample and waste solutions [10–15]. This method
also provides advantages in solvent extraction, such as a large interfacial area/volume ratio, short diffusion distance and stable measurement of laminar flow [16]. The mass transfer process at the interface between the aqueous and organic phases in the micro-channel was reported [17]. Yttrium was separated from Zn by the difference in the extraction rates in the micro-channel of the two-phase flow and three-phase flow [18,19]. However, the extraction efficiency did not reach 100%