Separation and determination of cadmium in water samples based on functionalized carbon nanotube by syringe filter membrane- micro solid-phase extraction

Jamshid Rakhtshah

doi:10.24200/amecj.v4.i01.132

Abstract

A simple and fast separation of cadmium (Cd) based on functionalized carbon nanotubes with 2,3-dimercapto-1-propanol (CNTs@DHSP) was achieved in water samples before a determination by atom trap flame atomic absorption spectrometry (AT-FAAS). In this study, Cd(II) ions were extracted by syringe filter membrane-micro solid phase extraction procedure(SFM-μ-SPE). Firstly, 20 mg of the CNTs@DHSP as solid-phase added to 20 mL of water sample in a syringe, then dispersed for 3 min after adjusting pH up to 7 and pass through SFM very slowly. After extraction, the Cd(II) ions were back-extracted from SFM/CNTs@DHSP by 1.0 mL of eluent in acidic pH. Finally, the cadmium concentration was measured by AT-FAAS. Under the optimal conditions, the linear range (2–90 µg L−1), LOD (0.75 µg L−1) and enrichment factor (19.6) were obtained (RSD<1.5%). The adsorption capacity of Cd(II) with the CNTs@DHSP was obtained about 152.6 mg g-1. The method was validated by certified reference materials (SRM, NIST) and ET-AAS in water samples.

Highlights

Cadmium (Cd) as a toxic non-essential metal release from industrial activity to water, soil, food, agricultural product and air, cadmium ions cause to environmental and human health hazards
SH group of DHSP on the surface of CNTs can be complexed with cadmium ions in a water solution (Fig.2)
The results showed that 1.5 mol L-1 HNO was quantitatively back-extracted the cadmium from syringe Whatman filter membrane (SFM)/CNTs@DHSP adsorbent

Summary

Introduction

Cadmium (Cd) as a toxic non-essential metal release from industrial activity to water, soil, food, agricultural product and air, cadmium ions cause to environmental and human health hazards. The cadmium intake to the human body is about 7 μg Cd per week This value cause to create the cadmium concentration in renal and urine between 100-200 μg g-1 and less than 0.5 μg g-1 creatinine, respectively. Various analytical techniques can be used for cadmium extraction in different water, foods and environmental samples. The various methods such as flame atomic absorption spectrometry (AAS) [12], the optical microscopy based on laser-induced photoluminescence (UV– VIS-NIR) [13], the SrFe O @CTAB magnetic

Methods

Results

Conclusion