In this study, the CuS nanoparticles loaded on activated carbon (CuS‐NPs‐AC) composite was synthesized and then, characterized by XRD and FE‐SEM analyses. The prepared composite was used as a potential adsorbent for the simultaneous ultrasound‐assisted removal of Indigo Carmine (IC) and Safranin‐O (SO). The CuS‐NPs‐AC dose (0.01‐0.03 g), sonication time (1‐5 min), initial SO concentration (5‐15 mg L‐1) and initial IC concentration (5‐15 mg L‐1) as expectable effective parameters were studied by central composite design (CCD) under response surface methodology (RSM) to obtain an useful knowledge about the effect of simultaneous interaction between IC and SO on their removal percentage. The optimum SO and IC removal percentages were determined to be 98.24 and 97.15% at pH = 6, 0.03 g of the CuS‐NPs‐AC, 3 min sonication time, 12 and 10 mg L‐1 of IC and SO. The values of coefficient of determination (R2) for SO and IC were 0.9608 and 0.9796, respectively, indicating the favorable fitness of the experimental data to the second order polynomial regression model. The isotherm data were well correlated with Freundlich model. The maximum monolayer adsorption capacities of 87.5 and 69.90 mg g‐1 at room temperature for IC and SO in the investigated binary system expressed the high efficiency of the novel adsorbent for water cleanup within a short time. The investigation of correlation between time and rate of adsorption revealed that IC and SO adsorption onto the CuS‐NPs‐AC followed pseudo‐second‐order and intra‐particle diffusion simultaneously. 相似文献
The solid phase extraction (SPE) is described for preconcentration of the antidepressant drugs amitriptyline and nortriptyline prior to their determination by HPLC with UV detection. It is based on the use of water-dispersible core-shell nanoparticles (NPs) of the Fe3O4@ZrO2@N-cetylpyridinium type. The positively charged surfactant N-cetylpyridinium forms mixed aggregates with the drugs on the surface of the core-shell and thereby improves the adsorption of amitriptyline and nortriptyline through hydrophobic and/or ionic interactions. Their extraction depends on the type and amount of surfactant, sample pH, extraction time, desorption conditions, sample volume and amount of NPs that were optimized by application of experimental design. The enrichment factors are 220 and 250, respectively, for amitriptyline and nortriptyline, and the detection limits are 0.04 and 0.08 ng·mL‾1. This protocol enables accurate and precise quantification of the two drugs in complex and low content samples. It was applied to the determination of the two drugs in plasma samples with relative recoveries in the range from 89 to 105 % and RSDs less than 4 %.
The development of a solid-phase extraction (SPE) procedure for the pre-concentration of trace amounts of Pb2+ ion on 2-furan-2-yl-1-furan-2-ylmethyl-1H-benzoimidazole loaded on activated carbon modified with silver nanoparticles (L-AC-Ag-NP) was presented. The metal ion retained on the sorbent was quantitatively determined via complexation with the ligand. The complexed metal ion was efficiently eluted using 10 mL of 4 mol L?1 sulphuric acid in 10 w/v% acetone. The influences of the analytical parameters, including pH, amounts of the ligand and the solid phase, eluent conditions and sample volume, on the recoveries of the metal ion were optimised. Using the optimised parameters, the linear response of the SPE method for Pb2+ ion were in the ranges of 0.2–160 µg L?1, and the detection limit for Pb2+ ion was 0.034 µg L?1. The proposed method exhibits a pre-concentration factor (PF) of 80 and an enhancement factor of 30 for Pb2+ ion. The presented results demonstrate the successful application of the proposed method for the determination of Pb2+ ion in some real samples with high recoveries (>93%) and reasonable relative standard deviation (RSD < 2%). 相似文献
In the first, Cadmium selenide Nanoparticle loaded on activated carbon (CdSe-NP-AC) has been synthesized and characterized by different techniques including XRD and SEM. Then, this new adsorbent successfully has been applied for the removal of muroxide (MO) from aqueous solution in batch studies, while the effect of various experimental parameters like initial pH (pH(0)), contact time, amount of (CdSe-NP-AC) and initial MO concentration (C(0)) on its removal percentage was examined by one at a time optimization method. It was found following optimization of variable, the adsorption of MO onto (CdSe-NP-AC) followed pseudo-second-order kinetics and show Tempkin and Langmuir models for interpretation of experimental data. It was observed that by increasing the temperature the removal percentage was improved and the positive change in entropy (ΔS°) and heat of adsorption (ΔH°) show the endothermic nature of process, while the high negative value in Gibbs free energy change (ΔG°) indicates the feasible nature of adsorption process. 相似文献
In the presented work, the conditions for cloud point extraction of iron from aqueous solutions using 7-iodo-8-hydroxyquinolin-5-sulphonic
acid (Ferron) was investigated and optimized. The procedure is based on the separation of its ferron complex into the micellar
media by adding the surfactant Triton X-114. After phase separation, the surfactant-rich phase was dissolved with 1.0 M HNO3
in methanol. Iron was determined by flame atomic absorption spectrometry. Optimization of the pH, ligand and surfactant quantities,
incubation time, temperature, viscosity, sample volume, and interfering ions were investigated. The effects of the matrix
ions were also examined. The detection limits for three times the standard deviations of the blank for iron was 0.4 ng m L-1,
enrichment factor of 19.6 and preconcentration factor of 30 could be achieved. The validity of cloud point extraction was
checked by employing real samples including soil, blood, spinach, milk, meat, liver and orange juice samples using the standard
addition method, which gave satisfactory results.In the presented work, the conditions for cloud point extraction of iron
from aqueous solutions using 7-iodo-8-hydroxyquinolin-5-sulphonic acid (Ferron) was investigated and optimized. The procedure
is based on the separation of its ferron complex into the micellar media by adding the surfactant Triton X-114. After phase
separation, the surfactant-rich phase was dissolved with 1.0 M HNO3 in methanol. Iron was determined by flame atomic absorption spectrometry. Optimization of the pH, ligand and surfactant quantities,
incubation time, temperature, viscosity, sample volume, and interfering ions were investigated. The effects of the matrix
ions were also examined. The detection limits for three times the standard deviations of the blank for iron was 0.4 ng m L−1, enrichment factor of 19.6 and preconcentration factor of 30 could be achieved. The validity of cloud point extraction was
checked by employing real samples including soil, blood, spinach, milk, meat, liver and orange juice samples using the standard
addition method, which gave satisfactory results.
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A chemically modified electrode was constructed for rapid, simple, accurate, selective and highly sensitive simultaneous determination of Cu(II) and Cd(II) using square wave anodic stripping voltammetry. The electrode was prepared by incorporation of SiO2 nanoparticles, coated with a newly synthesized Schiff base, in carbon paste electrode. The limit of detection was found to be 0.28 ng mL?1 and 0.54 ng mL?1 for Cu(II) and Cd(II), respectively. The proposed chemically modified electrode was used for the determination of copper and cadmium in several foodstuffs and water samples. 相似文献