Simultaneous application of cloud point and solid-phase extraction for determination of Fe(III) and Cu(II) ions by using SnO₂nanopowder in micellar medium

Abstract

A new approach was developed for sensitive determination of Fe(III) and Cu(II) ions using SnO 2 nanopowder in the micellar medium on the contrary conventional cloud point extraction studies. The presented method contains a combination of solid-phase extraction and cloud point extraction. According to this procedure, the metal ions were firstly retained on modified SnO 2 nanopowder and then passed to the surfactant-rich phase. The effect of experimental variables including pH, concentration of reagents, eluting solution, incubation time, equilibration temperature, sample volume, and effects of interfering ions have been investigated and optimized systematically. The calibration graphs were linear in the range of 0.23-100.00 μg L −1 and 0.30-110.00 μg L −1 for Fe(III) and Cu(II), respectively. Under optimized conditions, the limits of detections were 0.07 and 0.09 μg L −1 for Fe(III) and 0.09 μg L −1 for Cu(II). The proposed method offers satisfactory analytical features by means of combining two different and efficient preconcentration techniques. In addition, the method can be evaluated as an alternative and fast method according to only-surfactant-mediated extractions. The validation of method was carried out by recovery tests and certified reference material (CRM) analysis. The acceptable and compatible results were obtained in the analysis of CRM and real samples.

Photocatalytic degradation of norfloxacin and its intermediate degradation products using nitrogen‐doped activated carbon–CuS nanocomposite assisted by visible irradiation

“…Figure shows quantitative recoveries (>95%) are obtained at pH = 9, and then they begin to decline. pH is a key factor in the production rate of hydroxyl radicals; in addition, initial pH of the solution controls the protonation of the functional groups on the adsorbent (catalyst) surface and degree of ionization of the adsorbate and has an important impact on the surface charge of the adsorbent . The effect of initial pH on the photocatalytic degradation of pollutants is contingent upon the pollutant type and the zero point charge of the photocatalyst…”

“…pH is a key factor in the production rate of hydroxyl radicals; in addition, initial pH of the solution controls the protonation of the functional groups on the adsorbent (catalyst) surface and degree of ionization of the adsorbate and has an important impact on the surface charge of the adsorbent. [38][39][40][41] The effect of initial pH on the photocatalytic degradation of pollutants is contingent upon the pollutant type and the zero point charge of the photocatalyst. [42] According to Figure 8, the effect of pH on the degradation rate was enhanced with an increase of pH, and reached the optimal point at pH = 9; subsequently, it reduced again subject to excessive basic conditions.…”

Synthesis of ZnO photocatalyst modified with activated carbon for a perfect degradation of ciprofloxacin and its secondary pollutants

“…The pH of the solution is one of the most significant variables in adsorption and degradation investigations, since initial pH of the solution controls the ionization degree of the adsorbate and protonation of the functional groups on the catalyst surface . pH also affects the surface charge of adsorbents . The effect of initial pH on the photocatalytic degradation of pollutants is contingent upon the pollutant type and the zero point charge (zpc) of the photocatalyst .…”

“…[47] pH also affects the surface charge of adsorbents. [48] The effect of initial pH on the photocatalytic degradation of pollutants is contingent upon the pollutant type and the zero point charge (zpc) of the photocatalyst. [49] The zero point charge of ZnO-AC was investigated via ParticleMetrix Stabisizer PMX 200C.9.0, revealing zpc of 9 which is in good agreement with the literature.…”

Enhanced dispersive solid phase extraction assisted by cloud point strategy prior to fluorometric determination of anti-hepatitis C drug velpatasvir in pharmaceutical tablets and body fluids

“…11 Dispersive solid phase extraction (dSPE) has many advantages such as rapidity and the provision of more concentrated extracts. 12 In addition, cloud point extraction (CPE) offers several merits such as low toxicity, high efficiency and simplicity [13][14][15] and so nds wide applicability in analysis of hydrophobic analytes especially with interfering substances. 16 Combination of dSPE and CPE were previously reported for the analysis of Fe(III) and Cu(II), 13 doxazosin and alfuzosin 17 and arsenic in natural water.…”