Résumé: phishing scams. Skip to main content Search Enter your search terms here Home Journals Sensor Review Volume 44 Issue 6 Voltammetric determination of a UV filter pollutant using a platinum electrode modified by a polymer membrane based on ß-cyclodextrin To read this content please select one of the options below: £32.00 (excl. tax) 30 days to view and download Voltammetric determination of a UV filter pollutant using a platinum electrode modified by a polymer membrane based on ß-cyclodextrin Roumaissa Laieb, Ilhem Ghodbane, Rahma Benyahia, Rim Lamari, Saida Zougar, Rochdi Kherrrat Sensor Review ISSN: 0260-2288 Article publication date: 6 August 2024 Issue publication date: 20 November 2024 Purpose This study aims to develop an electrochemical sensor for the detection of benzophenone (BP) as an alternative to conventional techniques that are known, expensive, complex and less sensitive. Design/methodology/approach The developed sensor is a platinum electrode modified with a plasticized polymer film based on ß-cyclodextrin, using PVC as the polymer, PEG as the plasticizer and ß-CD as the ionophore. This sensor is characterized by various techniques, such as optical microscopy, scanning electron microscopy and cyclic voltammetry. This latter is also used for analyzing kinetic processes at the electrode/electrolyte interface and to evaluate the selectivity and sensitivity of the sensor. Findings The results highlight the performance of our sensor. In fact, it exhibits a linear response extending from 10−19 to 10−13 M, with a correlation coefficient of 0.9836. What is more, it has an excellent detection limit of 10−19 M and a good sensitivity of 21.24 µA/M. Originality/value The results of this investigation demonstrated that the developed sensor is an analytical tool of choice for the monitoring of BP in the aqueous phase. The suggested sensor is fast, simple, reproducible and inexpensive.

Résumé: Purpose This paper aims to focus on the development and characterization of a new electrochemical sensor, designed for the detection of methylene blue present in aqueous medium. Design/methodology/approach This sensor is obtained through the coupling of a polymeric membrane and an ion-sensitive electrode (platinum electrode). The preparation of the polymeric membrane involves the incorporation of a receptor: β-cyclodextrin (β-CD), a polymer (polyvinylchloride) and a plasticizer (dioctylphtalate). Cyclic voltammetry method (CV) was used to investigate the electrical properties of this electrochemical sensor. The effect of the experimental parameters such as dye initial concentration, scan rate, interfering elements presence and additional Nafion membrane presence was investigated in this paper. Findings The results are interesting because the developed sensor gives a linear response in concentrations range of 10−13 M–10−3 M with a good correlation coefficient of 0.979 and a detection limit of 10−13 M, which reflects the sensitivity of this sensor to the target element. The sensibility value is equal to 2. 40 µA mol−1 L. Originality/value The present study has shown that the modified electrode is a very good candidate in terms of price, sensibility and reproducibility for the construction of the sensitive sensor for the control of wastewater containing methylene blue.

Résumé: Purpose This paper aims to focus on the development and characterization of a new electrochemical sensor, designed for the detection of methylene blue present in aqueous medium. Design/methodology/approach This sensor is obtained through the coupling of a polymeric membrane and an ion-sensitive electrode (platinum electrode). The preparation of the polymeric membrane involves the incorporation of a receptor: β-cyclodextrin (β-CD), a polymer (polyvinylchloride) and a plasticizer (dioctylphtalate). Cyclic voltammetry method (CV) was used to investigate the electrical properties of this electrochemical sensor. The effect of the experimental parameters such as dye initial concentration, scan rate, interfering elements presence and additional Nafion membrane presence was investigated in this paper. Findings The results are interesting because the developed sensor gives a linear response in concentrations

Résumé: Purpose The purpose of this work is to explore electrical properties of an electrochemical sensor designed for the detection of malachite green (MG) present in an aqueous solution. Design/methodology/approach The present sensor consists in the spatial coupling of a polymeric membrane and an ion-sensitive electrode (platinum electrode). The preparation of the polymeric membrane involves the incorporation of an ionophore (D2HPA), a polymer (polyvinylchloride [PVC]) and a plasticizer (dioctyl phthalate [DOP]). Several techniques have been used to characterize this sensor: the cyclic voltammetry, the electrochemical impedance spectroscopy and the optical microscopy. The sensibility, the selectivity and the kinetic study of a modified platinum electrode have been evaluated by cyclic voltammetry. Findings The obtained results reveal the possibility of a linear relationship between the current of reduction peaks and MG concentration. A linear response was obtained in a wide-concentration range that stretches from 10−5 to 10−13 mol L−1, with a good correlation coefficient (0.976) and a good detection limit of 5.74 × 10−14 mol L−1 (a signal-to-noise ratio of 3). In addition, the voltammetric response of modified electrode can be enhanced by adding a layer of Nafion membrane. Under this optimal condition, a linear relationship was obtained, with a correlation coefficient of 0.986 and a detection limit of 1.92 × 10−18 mol L−1. Originality/value In the present research, a convenient, inexpensive and reproducible method for the detection of MG was developed. The developed sensor is capable of competing against the conventional techniques in terms of speed, stability and economy.

Résumé: Due to their significantly harmful impact on the environment and human health, the qualitative and quantitative determination of cresols receives great attention. In this study, a highly sensitive and selective polymeric membrane incorporating β-cyclodextrin was prepared for the determination of m-cresol in aqueous medium. Impedance spectroscopic data for this impedancemetric sensor exhibits complex impedance over a range of frequencies (1 Hz–100 kHz) and is well-fitted with a proposed equivalent electrical circuit model. The effect of m-cresol on the high-frequency arc resistance is described by a linear law at all m-cresol concentrations, indicating the possibility of utilizing the impedance spectra as the main sensing signal. The linear range and the detection limit of the calibration curve are 1.79 × 10−12 to 1.94 × 10−2 g/L, 1.79 × 10−12 g/L, respectively. In addition to high selectivity for m-cresol, the sensor possesses a good working lifetime.

Résumé: The objective of this work is the study the functionality of a chemical sensor, designed for the detection of Malachite green in aqueous medium. This sensor is constituted by the spatial coupling of a polymeric membrane and an ion sensitive electrode (platinum electrode). The preparation of the polymeric membrane involves the incorporation of an ionophore (D2HPA), a polymer (PVC) and a plasticizer (DOP). Electrochemical impedance spectroscopy and cyclic voltammetry techniques were used to explore the electrical properties of the sensor. Obtained results show that the developed sensor has a linear response in the concentration range that stretches from 10–3 M to 10–14 M, with a good correlation coefficient of 0.988 and a detection limit of 10–14 M for a polarization of –100 mV which indicates the sensitivity of the sensor overlooked the target element.

Résumé: The efficiency of eucalyptus bark as a low cost sorbent for removing cadmium ions from aqueous solution has been investigated in batch mode. The equilibrium data could be well described by the Langmuir isotherm but a worse fit was obtained by the Freundlich model. The five linearized forms of the Langmuir equation as well as the non-linear curve fitting analysis method were discussed. Results show that the non-linear method may be a better way to obtain the Langmuir parameters. Maximum cadmium uptake obtained at a temperature of 20 °C was 14.53 mg g−1. The influence of temperature on the sorption isotherms of cadmium has been also studied. The monolayer sorption capacity increased from 14.53 to 16.47 when the temperature was raised from 20 to 50 °C. The ΔG° values were negative, which indicates that the sorption was spontaneous in nature. The effect of experimental parameters such as contact time, cadmium initial concentration, sorbent dose, temperature, solution initial pH, agitation speed, and ionic strength on the sorption kinetics of cadmium was investigated. Pseudo-second-order model was evaluated using the six linear forms as well as the non-linear curve fitting analysis method. Modeling of kinetic results shows that sorption process is best described by the pseudo-second-order model using the non-linear method. The pseudo-second-order model parameters were function of the initial concentration, the sorbent dose, the solution pH, the agitation speed, the temperature, and the ionic strength.

Résumé: In this study, eucalyptus camaldulensis bark, a forest solid waste, is proposed as a novel material for the removal of mercury(II) from aqueous phase. The operating variables studied were sorbent dosage, ionic strength, stirring speed, temperature, solution pH, contact time, and initial metal concentration. Sorption experiments indicated that the sorption capacity was dependent on operating variables and the process was strongly pH-dependent. Kinetic measurements showed that the process was uniform and rapid. In order to investigate the mechanism of sorption, kinetic data were modeled using the pseudo-first-order and pseudo-second-order kinetic equations, and intraparticle diffusion model. Among the kinetic models studied, the pseudo-second-order equation was the best applicable model to describe the sorption process. Equilibrium isotherm data were analyzed using the Langmuir and the Freundlich isotherms. The Langmuir model yields a much better fit than the Freundlich model. Isotherms have also been used to obtain the thermodynamic parameters such as free energy, enthalpy, and entropy of sorption. The maximum sorption capacity was 33.11 mg g−1 at 20 °C and the negative value of free energy change indicated the spontaneous nature of sorption. These results demonstrate that eucalyptus bark is very effective in the removal of Hg(II) from aqueous solutions.

Résumé: Studies on a batch sorption process using wheat bran as a low cost sorbent was investigated to remove cadmium ions from aqueous solution. The influence of operational conditions such as contact time, cadmium initial concentration, sorbent mass, temperature, solution initial pH, agitation speed and ionic strength on the sorption kinetics of cadmium was studied. Pseudo-second-order model was evaluated using the six linear forms as well as the non-linear curve fitting analysis method. Modeling of kinetic results shows that sorption process is best described by the pseudo-second-order model using the non-linear method. The sorption of cadmium was found to be dependent on initial concentration, sorbent mass, solution pH, agitation speed, temperature, ionic strength and contact time. The value of activation energy (12.38 kJ mol−1) indicates that sorption has a low potential barrier corresponding to a physical process. Sorption equilibrium isotherms at different temperatures was determined and correlated with common isotherm equations such as Langmuir and Freundlich models. It was found that the Langmuir model appears to well fit the isotherm data but a worse correlation was obtained by the Freundlich model. The five Langmuir linear equations as well as the non-linear curve fitting analysis method were discussed. Results show that the non-linear method may be a better way to obtain the Langmuir parameters. Thermodynamic parameters such as ΔH°, ΔS° and ΔG° were calculated. These parameters indicate that the sorption of cadmium by wheat bran is a spontaneous process and physical in nature involving weak forces of attraction and is also endothermic.