Preconcentration of ultra-traces of Cu(II) in water samples using SBA-15 sorbent modified with a thiocarbohydrazide ligand prior to determination by flame atomic absorption spectrometry

Abstract

A simple, reliable and rapid method for the extraction of ultra-trace copper(II) using nanoporous SBA-15 sorbent modified with a thiocarbohydrazide ligand, and determination by flame atomic absorption spectrometry is presented. The optimum parameters of the method were obtained as pH of aqueous solution 5, sorbent amount 2 mg, stirring time 20 min and 0.4 M HCl solution as the eluent solvent. This method has a breakthrough volume greater than 1500 mL with a concentration factor of more than 300, linear range 0.8–2500.0 μg L-1, limit of detection 0.253 μg L-1 and limit of quantification 0.844 μg L-1 for copper(II). The capacity of 2 mg of modified SBA-15was found to be 123.00±0.04 mg g-1. Standard deviations were 3.3, 2.3 and 2.1 % for 1, 2 and 4 μg mL-1, respectively (n = 5). This method was successfully applied for the determination of copper(II) in different real samples, especially in the food samples.

Keywords

• nanoporous sorbent
• thiocarbohydrazide
• flame atomic absorption spectrometry
• copper(II)