Application of 1-(2-pyridylazo)-2-naphthol-modified nanoporous silica as a technique in simultaneous trace monitoring and removal of toxic heavy metals in food and water samples

Abstract

Solid-phase extraction is one the most useful and efficient techniques for sample preparation, purification, cleanup, preconcentration, and determination of heavy metals at trace levels. In this paper, functionalized MCM-48 nanoporous silica with 1-(2-pyridylazo)-2-naphthol was applied for trace determination of copper, lead, cadmium, and nickel in water and seafood samples. The experimental conditions such as pH, sample and eluent flow rate, type, concentration and volume of the eluent, breakthrough volume, and effect of coexisting ions were optimized for efficient solid-phase extraction of trace heavy metals in different water and seafood samples. The content of solutions containing the mentioned heavy metals was determined by flame atomic absorption spectrometry (FAAS), and the limits of detection were 0.3, 0.4, 0.6, and 0.9 ng mL(-1) for cadmium, copper, nickel, and lead, respectively. Recoveries and precisions were >98.0 and <4%, respectively. The adsorption capacity of the modified nanoporous silica was 178 mg g(-1) for cadmium, 110 mg g(-1) for copper, 98 mg g(-1) for nickel, and 210 mg g(-1) for lead, respectively. The functionalized MCM-48 nanoporous silica with 1-(2-pyridylazo)-2-naphthol was characterized by thermogravimetry analysis (TGA), differential thermal analysis (DTA), transmission electron microscopy (TEM), Fourier transform infrared spectrometry (FT-IR), X-ray diffraction (XRD), elemental analysis (CHN), and N2 adsorption surface area measurement.

Kinetic, isotherm and thermodynamic studies on biosorption of chromium(VI) by using activated carbon from leaves of Ficus nitida

“…The removal of toxic metals from wastewater has been achieved using various methods like ion electro dialysis [6], sedimentation [7], ion exchange [8, 9], biological operations [10], coagulation/flocculation [11], nanofiltration technology [12], solid phase extraction [13], adsorption by chemical substances [14, 15] and electrokinetic remediation [16]. All these techniques suffer from multiple drawbacks such as high capital and operational costs and disposal of residual metal sludge [17].…”

Solid Phase Extraction of Trace Al(III), Fe(II), Co(II), Cu(II), Cd(II) and Pb(II) Ions in Beverages on Functionalized Polymer Microspheres Prior to Flame Atomic Absorption Spectrometric Determinations

“…[13][14][15][16][17] SPE is a surface dependent method, and so the particle size and surface area of the sorbent materials directly affect the efficiency of SPE. 18 Polymer materials have been of great interest as adsorbents for the solid phase extraction of metal ions from aqueous solutions, owing to their excellent mechanical, thermal and chemical stability, and reusability. 6,17,[19][20][21][22][23] These polymers are functionalized by metal chelate forming agents or ligands, in which the ligand molecules are covalently bonded to the polymer active sites consisting of functional groups such as hydroxyl, carboxyl, amino, glycidyl, pyridine and chloride, in order to obtain further selectivity, affinity and capacity towards the metal ions.…”

Solid phase extraction and trace monitoring of cadmium ions in environmental water and food samples based on modified magnetic nanoporous silica

“…Since the synthesis of M41S materials in 1992, mesoporous silica materials, due to their high surface areas, well-defined pore size, and tunable pore sizes, have been widely used in the field of adsorption of heavy metal ions [20][21][22][23][24]. Many efforts have been devoted to synthesis, characterizations, and applications of mesoporous silica materials.…”