Separation/Preconcentration of Xylenol Orange Metal Complexes on Amberlite XAD-16 Column for Their Determination by Flame Atomic Absorption Spectrometry

Selective solid-phase extraction of Ni(II) by an ion-imprinted polymer from water samples

“…To determine trace metals in aquatic environments by instrumental analysis, a separation and preconcentration technique is frequently required, because of low concentration of trace metal ions and presence of interferences [1][2][3][4][5]. Many sample pretreatment methods including solvent extraction, cloud point extraction, solid-phase extraction, membrane filtration, electrodeposition, flotation, coprecipitation and ion exchange have been developed for preconcentration of trace metals from natural waters [3][4][5][6][7][8][9][10][11][12][13].…”

On-line separation and preconcentration of lead(II) by solid-phase extraction using activated carbon loaded with xylenol orange and its determination by flame atomic absorption spectrometry

“…Xylenol orange (XO) is a metal indicator, which is widely used for analytical determination [6,11,12]. It has a large formation constant with Pb(II).…”

“…The method is a batch method, has higher limit of detection (>2 ng mL −1 Pb(II)) and suffer from many interfering ions such as Fe(II), Mn(II), Cd(II), Zn(II) and phosphate. In addition, Amberlite XAD-16 loaded with XO [6], Amberlite XAD-2000 [7] and Amberlite XAD-1180 [8] have been reported by M. Soylak et al as suitable solid phases for preconcentration of heavy metals including Cr, Cu, Ni, Zn and Pb. However, those methods are not selective for Pb(II).…”

Three modified activated carbons by different ligands for the solid phase extraction of copper and lead

“…The selectivity of the modified solid phases toward certain metal ions is attributed to several well known factors such as the size of the organic modifier [8], the activity of the loaded surface groups [9,10], the type of the interacting donor atom and metal ion and the reported well known phenomenon of hard-soft acid-bases [11]. The reasons for widespread application of the activated carbon as a trace collector for metal ion preconcentration [12][13][14][15][16][17][18][19][20][21][22][23][24][25][26] are strong interaction and quantitative adsorption of molecules with electrons on activated carbon. Activated carbon is a hydrophobic adsorbent which adsorbs non-polar or slightly polar substances in aqueous solutions, metal ions to be preconcentrated need to be transformed to corresponding metal chelates.…”