Atomic Absorption Spectrometric Determination of Trace Amounts of Copper and Zinc after Simultaneous Solid-Phase Extraction and Preconcentration onto Modified Natrolite Zeolite

Abstract

This work assesses the use of modified natural natrolite zeolite as an adsorptive material for the separation and preconcentration of trace amounts of ions. In this work we investigated the potential of modified natural natrolite zeolite for the simultaneous separation and preconcentration of trace amounts of copper and zinc ions. We have developed a simple, rapid, selective, sensitive and economical method for the simultaneous separation and preconcentration of trace amounts of copper and zinc in an aqueous medium using 2-(5-bromo-2-pyridylazo)-5-diethylaminophenol (5-Br-PADAP) as an analytical reagent. The sorption was quantitative in the pH range 7.5 -9.5, whereas quantitative desorption occurred instantaneously with 5.0 mL of 2 mol L -1 nitric acid. Linearity was maintained between 0.05 -6.0 μg mL -1 for copper and 0.02 -1.5 μg mL -1 for zinc in the final solution. Ten replicate determinations of 1.0 μg mL -1 copper and 0.5 μg mL -1 zinc in a mixture gave mean absorbances of 0.1687 and 0.2788 with relative standard deviations of ±1.2% and ±1.3%, respectively. The detection limits were 0.03 ng mL -1 for Cu(II) and 0.006 ng mL -1 for Zn(II) in the original solution (3σbl/m). Different parameters, such as the effect of the pH, flow rate, breakthrough volume and interference of a large number of anions and cations, were studied and the proposed method was used for the determination of these metal ions in water as well as standard samples (e.g. Nippon Keikinzoku Kogyo (NKK) CRM, No. 916 and No. 920 aluminum alloy, National Institute for Environment Studies (NIES) No. 1 pepperbush and NIES No. 2 pond sediment). The determination of these metal ions in standard samples showed that the proposed method has good accuracy (recovery > 97%).

Cloud point extraction for the determination of copper in environmental samples by flame atomic absorption spectrometry

“…The preconcentration factor and detection limits of the proposed method are comparable with various separationpreconcentration methods. [13][14][15][28][29][30][31][32][33][34] The low RSD of real sample analysis is an indication of methods versatility for real sample. …”

Facile Synthesis of a Luminescent Material, PAN@{SiO2}n, Having a Simultaneous Binding Capacity of High and Low Oxidation States: HOMO and LUMO, Quantum-mechanical Descriptor of Break-through Capacity

“…22,[53][54][55][56][57][58][59][60][61][62][63][64][65][66] Most of the earlier synthesis required complicated steps with stringent reaction conditions (like refluxing: 24 -90 h, starring, very high or low temperature, repetitive filtrations, inert atmosphere, vacuum, costly and hazardous chemicals). 11,17,22 Moreover, the cross-linking activity of bridging component increases the size of earlier used FSG-X, and their surface activities were turned down to a moderate level.…”

Zeolite/iron oxide composite as sorbent for magnetic solid-phase extraction of benzene, toluene, ethylbenzene and xylenes from water samples prior to gas chromatography⬜mass spectrometry

“…Several sorbents with different properties have been employed in SPE, including inorganic oxides, porous polymers, molecularly imprinted polymers, biosorbents or nanomaterials [8][9][10]. In addition, some publications have reported the use of zeolites for the preconcentration of inorganic [11][12][13] and organic [14,15] analytes. The original SPE has been modified several times to date, mainly related to miniaturization or automation [16].…”