Application of silica fume as a new SP-extractor for trace determination of Zn(II) and Cd(II) in pharmaceutical and environmental samples by square-wave anodic stripping voltammetry

Abstract

In this work, silica fume (SF) is used as a solidphase extractor for extraction of Zn(II) and Cd(II) from aqueous solutions. Characterization of SF is performed by Fourier transform infrared, X-ray diffraction, transmission and scanning electron microscopy. The optimum experimental conditions for the two metal ions are investigated using batch and column techniques. The maximum adsorption capacity values are found to be 54.13 and 121.28 mg g -1 at the optimum pH 6.0 and 8.0 for Zn(II) and Cd(II), respectively. The equilibrium data are analyzed using the Langmuir, Freundlich, and Temkin isotherms by nonlinear regression analysis. Also, the kinetics analysis revealed that the overall adsorption process is successfully fitted with the pseudo-second-order model. The method is applied for determination of the target metal ions in pharmaceutical and environmental samples using squarewave anodic stripping voltammetry. The limit of detection (LOD) values are 0.102 and 1.43 9 10 -3 mg L -1 for Zn(II) and Cd(II), respectively. The percentage recovery values are 98.8-100.5 % which indicate the success of the proposed method for determination of Zn(II) and Cd(II) without interfering effects.

Recent development of eco-friendly nanocomposite carbon paste electrode for voltammetric determination of Cd(II) in real samples

“…At the same temperature so that no organic compound traces are left. The final residue was treated with 0.5 mL concentrated hydrochloric acid and 1.0 – 2.0 mL 70%perchloric acid and evaporated to fumes so that all the cadmium metal changes to cadmium ions [ 43 ].…”

Electrochemical Assays for the Determination of Antidiabetic Drugs—A Review

“…As reported in the literature, several papers have been published for the electrochemical detection of glimepiride (GLI) using various kinds of working electrode ( Table 6 ). The vast majority of GLI voltametric sensors are based on the utilization of carbon-based electrodes, including carbon paste electrodes and glassy carbon electrodes [ 67 , 68 , 69 ], as well as hanging drop mercury electrodes [ 70 , 71 , 72 , 73 ]. These papers have focused on understanding the electrochemical behavior of GLI at a particular sensor and its quantitative determination, either alone or in combination with other antidiabetic drugs.…”

RSM Optimization of Direct Orange 26 Adsorption on Low-Cost Silica Fume Adsorbent

“…Due to the unique properties of silica fume, including high porosity and permeability, very small particle size, low specific gravity, high specific surface area, low thermal conductivity, good absorption capacity, and chemical inertness, it has received special attention (Zhang et al, 2012). The unique properties of silica fume have led to its use in the cement industry, the production of polymer products, and the absorption of pollutants (Ahmed, Gaber, & Rahim, 2017). Wang et al (2011) found that the performance of silica fume in adsorption of Rhodamine B from aqueous solutions is better than from coal ash (Wang & Chu, 2011).…”

“…Kalkan et al (2014) found silica fume has a high capacity to adsorb nickel (Kalkan, Nadaroglu, & Celebi, 2014). Nadaroglu et al (2013) and Ahmed et al (2015) showed that silica fume is a cheap and effective adsorbent for the removal of cadmium (II) and copper and zinc ions from wastewater (Ahmed et al, 2017;.…”