Preconcentration Of Nickel Research Articles

A simple and efficient supramolecular solvent based liquid phase microextraction method for the preconcentration of nickel from dandelion tea samples before FAAS quantification, and the practicality and greenness assessment of developed method

A sensitive, accurate and practical analytical method (supramolecular solvent based liquid phase microextraction – flame atomic absorption spectrometry (SUPRAS-LPME-FAAS) was developed for the determination of nickel in dandelion tea samples. All influential parameters of SUPRAS-LPME were optimized to attain low detection/quantification limits using a univariate optimization approach. Under the optimum SUPRAS-LPME-FAAS conditions, dynamic range, limit of detection (LOD) and limit of quantification (LOQ) were found to be 25.86–497.64 µg/kg, 8.20 µg/kg and 27.35 µg/kg, respectively. The detection power of FAAS system was augmented as 28-fold with the help of SUPRAS-LPME method. Recovery experiments were performed for the evaluation of the accuracy and the applicability of the SUPRAS-LPME-FAAS method and percent recovery results for the spiked dandelion tea samples were calculated between 86.0 and 131.8 % via matrix matching calibration strategy. Additionally, the practicality and greenness evaluations for the SUPRAS-LPME-FAAS method were carried out using BAGI and AGREEprep software, respectively.

Trace nickel determination in seawater matrix using combination of dispersive liquid-liquid microextraction and triethylamine-assisted Mg(OH)2 method.

In order to eliminate the effects of seawater matrix on the precise/accurate determination of elements, new and efficient analytical procedure requires. In this study, co-precipitation method based on the triethylamine (TEA)-assisted Mg(OH)2 was performed to eliminate side-effects of seawater medium on the determination with flame atomic absorption spectrometry (FAAS) prior to the preconcentration of nickel by an optimized dispersive liquid-liquid microextraction (DLLME) method. Under the optimum conditions of the presented method, the limit of detection and quantification (LOD, LOQ) values obtained for nickel were found as 16.1 and 53.8μgkg-1, respectively. Seawater samples collected from West Antarctic region were used for real sample applications to check the accuracy and applicability of developed method, and satisfying recovery results (86-97%) were obtained. In addition to this, the digital image-based colorimetric detection system and the UV-Vis system were applied to confirm the applicability of the developed DLLME-FAAS method in other analytical systems.

Simultaneous preconcentration and determination of trace metals in edible plants and water samples by a novel solvent bar microextraction using a meltblown layer of facemask as the extractant phase holder combined with FAAS

A new microextraction method as a facile, efficient, and safe intermediate sample preparation procedure was developed for simultaneous extraction and preconcentration of nickel (II), cobalt (II), and lead (II) in some vegetables and water samples. The new method uses a novel deep eutectic solvent as an extractant on the surface of a meltblown layer of a facemask with an iron wire inside of it. 2-(5-Bromo-2-pyridylazo)-5-diethylaminophenol (5-Br-PADAP) was used as a chelating reagent. The concentrations of the enriched ions were measured using a flame atomic absorption spectrophotometer (FAAS). The introduced method underwent significant parameter optimization, which may influence the extraction process efficiency. Under the best situations, the calibration curve of the method showed excellent linearity over the concentration range 2–150 μg L−1, 3–150 μg L−1, and 7–500 μg L−1 have satisfactory coefficients of determination (R2 ≥ 0.998) for nickel (II), cobalt (II), and lead (II), respectively. Detection limits were within 0.61 – 2.30 μg L−1, and the relative standard deviation values were fewer than 2.6 % (n = 10). Experimental results indicated that the presented method has a high ability to cleanly and enrich metal ions in several samples, including natural water, dill, coriander, and spinach leaves, with limited solvent consumption and low operating costs.

Deep eutectic solvent-based simultaneous complexation and preconcentration of nickel in Antarctic lake water samples for determination by flame atomic absorption spectrometry.

This study presents a simple, sensitive, and accurate method for the determination of nickel by flame atomic absorption spectrometry (FAAS). Prior to instrumental measurement, a deep eutectic solvent-based simultaneous complexation and preconcentration (DES-SCP) method was used to preconcentrate nickel from aqueous solution into measurable quantities. The efficiency of the extraction method was enhanced by forming a non-ionic complex of nickel using dithizone as ligand. By mixing the ligand with the DES extractant, simultaneous complexation and preconcentration of nickel were achieved in a single step. Under optimum conditions of the extraction method, the limit of detection (LOD) and the limit of quantification (LOQ) values were found to be 2.4 and 8.0ng/mL, respectively. With respect to direct FAAS measurement, the developed method enhanced the sensitivity of nickel determination by about 169 folds. The accuracy and applicability of the developed method were evaluated by performing spike recovery experiments with lake water sampled from Antarctica. Satisfactory recovery results in the range of 94.0-113.7% were recorded and this validated the developed method as an efficient and green alternative for nickel determination.

Preconcentration of Nickel by Magnetic Solid-Phase Extraction (MSPE) as the 2-(5-Bromo-2-Pyridylazo)-5-Diethylamino-Phenol (PADAP) Chelate upon Multiwalled Carbon Nanotubes (MWCNTs) with Determination by Flame Atomic Absorption Spectrometry (FAAS)

A magnetic solid phase extraction (MSPE) method for nickel as the 2-(5-bromo-2-pyridylazo)-5-diethylamino-phenol (PADAP) chelate was established prior to flame atomic absorption spectrometric (FAAS) determination. Magnetic multiwalled carbon nanotubes were used as the adsorbent. Analytical parameters affecting the extraction efficiency of nickel such as pH of the medium (8.0), mass of adsorbent (8.0 mg), eluent concentration and volume (4.0 mL of 1 M HNO3), extraction time (6.0 min), and model solution volume (20 mL) were optimized. In addition, matrix effects were investigated. The preconcentration factor was 5. The relative standard deviation was less than 5%. A standard addition recovery study was performed on water samples to evaluate the accuracy of the method and certified reference materials were used for validation. The limits of detection (LOD) and quantitation (LOQ) were 7.1 µg L−1 and 24.4 µg L−1, respectively. The proposed method was applied to determine nickel in tobacco samples.

Development of a green analytical chemistry method for off-line preconcentration of nickel in water and sediments samples with mini-column with bamboo fibres

ABSTRACT In this work, is proposed an analytical method for the determination of nickel in natural water and sediment samples using solid-phase extraction with a mini-column of bamboo fibres modified with 5-Br-PADAP and determination by flame atomic absorption spectrometry. Applying the characterisation techniques of fresh bamboo fibre aimed to define the morphology of the fibre and its physical characteristics. Turning to the optimisation of the variables for the adsorptive process of nickel. The system allows the determination of nickel with a limit of detection (LOD) of 0.75 μg L−1 and a limit of quantitation (LOQ) of 2.50 μg L−1. The precision was expressed as a relative standard deviation (RSD) of 3.4 and 3.8% for a nickel concentration of 20.0 and 50.0 μg L−1 respectively. The value of 78.0 was determined as the value for the enrichment factor. The accuracy was confirmed with spike tests with recuperations varying from 91% to 106% and 93% to 104% for water and sediment samples, respectively, and by comparison with the certified sample. The procedure was applied for nickel determination in natural water and sediment samples. The achieved concentrations varied from 4.0–53.2 and 3.7–55.8 µg L−1 for water and sediment samples, respectively.

Preconcentration of Nickel from Aqueous Environment Using Microspheric Nickel(II) Ion Imprinted Polymer

Preconcentration of Nickel from Aqueous Environment Using Microspheric Nickel(II) Ion Imprinted Polymer

Synthesis and adsorption characteristics of ionic imprinted polymers IIPs for removal and preconcentration of Nickel from aqueous solution

A novel Ni(II) ion-imprinted polymers (IIPs) was synthesized by bulk polymerization using different types of monomers such as Styrene and 1-vinyl imidazole, respectively. molar ratios of template, monomer and cross-linking agent for polymerization, solvents, Various monomers were studied to obtain the largest adsorption capacity. The prepared Nickel-IIPs were characterized using fourier-transform infrared spectroscopy (FTIR), Scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDX). The elution process has no influence on the three-dimension network structure surfaces of Nickel-IIPs. Nickel(II) ions could be eluted from IIPs successfully by mixture solution from ethanol and acetic acid. The maximum adsorption capacity of Nickel-IIPs was is 457.3µmol/g for Nickel-IIP1(using styrene as a monomer) and 355µmol/g for Nickel-IIP2(using 1-vinyl imidazole as a monomer). The adsorption by Nickel-IIPs followed a Langmuir isotherm models. Solid-phase extraction (SPE) syringe packed with ionic imprinted polymers (IIPs) were used to selective separation and preconcentration for Nickel(II) ion from aqueous solutions and digest the polymer to determination the Nickel by flame atomic absorption spectroscopy (AAS) Abbreviation IIP-SPE-FAAS

Determination of nickel in urine by ultrasonic-assisted ionic liquid microextraction-graphite furnace atomic absorption spectrometry

Objective: To set up a new method to determine the nickel of urine in urine using dispersive liquid-liquid microextraction (DLLME) coupled with graphite furnace atomic absorption spectrometry (GFAAS) . Methods: From September 2018 to September 2019, the methanol, pyrrolidine dithiocarbamate and ionic liquid 1-hexyl-3-methyl-imidazolium hexafluorophosphate were used as dispersive solvent, the chelating agent and extraction solvent for the preconcentration of nickel, respectively. After adding into buffer solution of pH 9, ultrasonic dissolving for 10 minutes, centrifugal separation and then discarding the supernatant, the precipitate was saved. Dissolving the precipitate by methanol, mixing thoroughly on a vortex mixer, the 15 μl of the mixed solution was used for determination by graphite furnace atomic absorption spectrometry. Results: The linear correlation coefficient of urine nickel concentration in the range of 2.0-10.0 μg/L, r=0.999, with the detection limitation of 0.43 μg/L. The recovery rate and the relative standard deviations were 95.6%-103.7% and 2.53%-4.82%, respectively. Conclusion: The method, which has low detection limit, high recovery rate and good precision, is suitable for the determination of nickel in urine for the occupational populations exposure to nickel and non-occupational exposure.

Experimental design and RSM on the recovery of Ni (II) ions by ELM using TX-100 as a biodegradable surfactant

ABSTRACT The present work deals with the extraction and pre-concentration of nickel (II) ions using emulsified liquid membrane (ELM) in the presence of di- (2-ethylhexyl) phosphoric acid (D2EHPA) as an extractant. The emulsion stability was achieved by the biodegradable surfactants Triton X-100 addition diluted in kerosene. Influence of operating conditions that affect ELM performance were investigated. A comparative study between the optimization parameters of this process was carried out both experimentally and with the Response Surface Methodology (RSM), in accordance with the Box–Behnken matrix. The following parameters were investegated: D2EHPA / Triton X-100 ratio between 0.5 and 3.5, initial concentration of the feed phase between 200 and 500 ppm and pH of the feed phase from 2.5–10. The transport of Ni (II) ions was evaluated according to the extraction yield as an analytical response and the optimal conditions were determined. It was found that the calculated values being in good agreement with experimental data that under the optimized conditions ([Ni] = 350 ppm, Vagitation = 200 rpm, t = 20 min and pH = 6.6), Ni (II) ions extraction was recorded more than 94% of efficiency.

Surface active ionic liquid‑assisted cloud point extraction method for preconcentration of nickel in environmental samples before its FAAS determination

Green, rapid and modified surface-active ionic liquid assisted cloud point extraction method (SAIL-CPE) was developed to preconcentrate trace levels of nickel Ni(II) ions in environmental samples perior to its detection by FAAS. The proposed method based on utilizing a mixture of a nonionic surfactant (Triton X-114) and a surface-active ionic liquid, 1-hexadecyl-3-methylimidazolium chloride (C16MeImCl), as an extracting phase for Ni(II) ions after the complexation with sunset yellow FCF at pH 6.5. The impact of different analytical parameters on improving the extraction efficiency was invistigated. In the range of 2.0-600 µg L−1, the calibration graph was linear with correlation coefficient of 0.9998. Limit of detection and preconcentration factor were 0.6 and 100. The reliability and precision of the proposed SAIL-CPE system as the relative standard deviation (RSD %) in the presence and absence of SAIL were examined by applying ten replicate determinations of 300 µg L-1 of Ni(II), and RSD % of the recoveries were found to be 1.40 and 2.9%, respectively. The validation of the proposed procedure was verified by test of certified reference materials (TMDA-51.3 fortified water, TMDA-53.3 fortified water and SRM spinach leaves 1570A) applying the standard addition method. Finally, the proposed SAIL-CPE method was developed and applied to preconcentrate and determine of trace levels of Ni(II) ions in real water, food and tobacco samples with satisfactory results.

Pre-concentration of nickel in laterite ores using physical separation methods

Nickel is an important metal globally with a consumption of about 2 million tons per year. This is supplied from both sulfide and laterite ores, but currently laterites are becoming more attractive for nickel production due to the depletion of high grade nickel sulfide ores. Laterites are generally processed through hydro or pyro-metallurgy and therefore, pre-concentration of nickel before such processes is very important.This paper examines the effects of different physical methods on pre-concentration of nickel in laterite ores. The effect of ore mineralogy on choosing the best strategy to upgrade nickel will be discussed. The findings of this project will help to unlock a substantial volume of nickel with significant value from laterite ores.

A Simple Pre-concentration Method for the Determination of Nickel(II) in Urine Samples Using UV-Vis Spectrophotometry and Flame Atomic Absorption Spectrometry Techniques

The cloud point technique was effectively utilized for extraction and pre-concentration of nickel(II) in urine samples before measurement by UV-Vis spectrophotometer and AAS techniques. The metal response to a para-aminophenol (PAP) reagent in a non-ionic surfactant Triton X-114 medium was to form the Ni-PAP complex. The adopted concentration for PAP, concentration of Triton X-114, pH effect and water bath temperature, incubation time, salt effect, and interference effects were all optimized. The calibration curve was linear over the range of (0.0625–1.25) mg L–1 with a correlation coefficient r2 of 0.9682 for the UV-Vis spectrophotometer at a λmax of 629 nm. The limit of detection was 0.005 mg/L. The relative standard deviation for six replicates was 1.07%. This method was applied successfully to determine copper (II) concentrations in 44 urine samples of occupational worker samples as determined by UV-Vis spectrophotometry and FAAS techniques.

Dispersive liquid–liquid microextraction based on green type solvents—"deep eutectic solvents"—for highly selective separation and efficient preconcentration of nickel in water samples

This study proposed a fast, feasible, and sensitive method for nickel preconcentration and separation in different actual samples through the use of deep eutectic solvent based dispersive liquid–liquid microextraction (DES-DLLME). This method involves dissolving a suitable extraction solvent in a dispersive solvent and its rapid syringing into water sample to obtain a turbid solution. Phase separation could be then carried out by centrifugation and the analyte can be determined. 2,2′-furildioxime was employed as the chelating agent through formation of a hydrophobic complex with nickel. To reach maximum recovery, some variables including type and volume of dispersive solvent, volume of extraction solvent, pH, 2,2′-furildioxime concentration, and salt concentration were optimized. Under optimal conditions, nickel calibration graph was linear in the range of 5.0–100 µg L−1. The detection limit and preconcentration factor were obtained as 1.7 µg L−1 and 40 µg L−1, respectively. Finally, this method was successfully applied for the extraction and determination of nickel in water samples with a relative recovery of 98.8–101.0%.

Separation and Preconcentration of Nickel(II) from Drinking, Spring, and Lake Water Samples with Amberlite CG-120 Resin and Determination by Flame Atomic Absorption Spectrometry.

In this study, Amberlite CG-120 adsorbent was used for the separation/preconcentration of Ni(II) ions in commercial drinking, spring and lake water samples before detection by flame atomic absorption spectrometry. Various optimization parameters for Ni(II) determination, such as pH, eluent type and concentration, sample and eluent flow rates, amount of adsorbent, were investigated to obtain better sensitivity, accuracy, precision and quantitative recovery. Furthermore, the interference effects of some ions on the recovery efficiency of Ni(II) were also investigated. The optimum experimental parameters were obtained in the case of pH 1; 5 mL of 4 mol L-1 HCl for eluent and 0.3 g for the adsorbent amount. The limit of detection was found to be 0.58 μg L-1 and linearity ranged from 5 to 50 μg L-1. The accuracy of the method was tested by the certified reference material of TMDA-70.2 Ontario Lake Water at a 95% confidence level.

Determination of Nickel by Flame Atomic Absorption Spectrometry after Preconcentration by Coprecipitation with Aluminum Hydroxide.

A method for nickel preconcentration by coprecipitation using Al(OH)3, followed by centrifugation and dissolution with HNO3 prior to a determination by flame atomic absorption spectrometry (FAAS), was investigated. Preconcentration factors of 30 and 200 were tested, and the detection limit (3 × sd/m, n = 10) was 0.05 μg L-1. The method was applied to real samples, and the results agreed with those obtained directly by graphite furnace atomic absorption spectrophotometry.

Development and Validation of a Sensitive Method for Trace Nickel Determination by Slotted Quartz Tube Flame Atomic Absorption Spectrometry After Dispersive Liquid-Liquid Microextraction.

In this study, dispersive liquid-liquid microextraction was systematically optimized for the preconcentration of nickel after forming a complex with diphenylcarbazone. The measurement output of the flame atomic absorption spectrometer was further enhanced by fitting a custom-cut slotted quartz tube to the flame burner head. The extraction method increased the amount of nickel reaching the flame and the slotted quartz tube increased the residence time of nickel atoms in the flame to record higher absorbance. Two methods combined to give about 90 fold enhancement in sensitivity over the conventional flame atomic absorption spectrometry. The optimized method was applicable over a wide linear concentration range, and it gave a detection limit of 2.1µgL-1. Low relative standard deviations at the lowest concentration in the linear calibration plot indicated high precision for both extraction process and instrumental measurements. A coal fly ash standard reference material (SRM 1633c) was used to determine the accuracy of the method, and experimented results were compatible with the certified value. Spiked recovery tests were also used to validate the applicability of the method.

Activated carbon cloth filled pipette tip for solid phase extraction of nickel(II), lead(II), cadmium(II), copper(II) and cobalt(II) as 1,3,4-thiadiazole-2,5-dithiol chelates for ultra-trace detection by FAAS

ABSTRACTA solid phase extraction method is established for preconcentration of nickel, lead, cadmium, copper and cobalt using pipette tip solid phase extraction. The presented process was dependent on chelation of analytes with 1,3,4-thiadiazole-2,5-dithiol, then allowing the solution to flow through an activated carbon cloth packed pipette tip. The adsorbed metal chelates on the surface of activated carbon cloth were eluted by 5 mL of 3 M HNO3. The concentrations of nickel, lead, cadmium, copper and cobalt were detected using a flame atomic absorption spectrometer (FAAS). The pipette tip solid phase extraction exhibit a preconcentration factor of 120. The limit of detection values were 2.7, 1.7, 1.3, 2.0 and 2.9 µg L−1 for Ni(II), Pb(II), Cd(II), Cu(II) and Co(II), respectively. Validation of the method was checked by the analysis of TMDA-53.3 and TMDA-64.2 certified reference materials. The method was successfully applied for water and fertiliser samples.

Sequential synthesis of a magnetic nano-adsorbent: How the first step identifies the final product

Three types of super paramagnetic core-shell nanoparticles have creatively been synthesized via three basic substances, Fe2+/Fe3+, methacrylic acid (MAA), and 2,2′-azobisisobutyronitrile (AIBN). It has been demonstrated that the order of addition of starting materials determines the type of products. Methacrylic acid coated magnetic nanoparticles (Fe3O4@MAA) with abundant double bonds on the surface, poly methacrylic acid coated magnetic nano particles (Fe3O4@PMAA) having plenty of surface carboxylic groups, and amphiphilic shell of methacrylic acid polymer on magnetic nano particles core (Fe3O4@AMPH) having both carboxyl and alkyl groups on the surface were prepared in three, separate one-pot, sequential synthesis. At first, the resultant magnetic nanoparticles (MNPs) were characterized by transmission electron microscopy (TEM), dynamic light scattering, X-ray spectroscopy, Fourier transform infrared spectroscopy (FTIR) and thermal analysis. Then, the colloidal stability of the synthesized particles was investigated in several common solvents such as water, 1-propanol, chloroform, and edible oil. Finally, the application of each nanoparticle was discussed. It was found that Fe3O4@MAA can be successfully applied as a core in polymerization procedure. Fe3O4@PMAA performed well in nickel uptake and can therefore be used as magnetic solid sorbent in nickel pre-concentration and remediation. Fe3O4@AMPH was well dispersed in oil, suggesting that it can be successfully used as a good extractor in dispersive solid phase pre-concentration and cleanup of both hydrophilic and hydrophobic compounds in heated edible oil samples.

Extraction and preconcentration of nickel, cadmium, cobalt, and lead cations using dispersive solid phase extraction performed in a narrow-bore tube

A new version of DSPE in a narrow-bore tube followed by HPLC-DAD was proposed for the analysis of Ni2+, Cd2+, Co2+, and Pb2+ cations. 2-Propanol is mixed with C18 sorbent and used for dispersing the sorbent into solution containing the cations oxinate complexes. The sorbent passes through the solution in a short time versus passing the solution from the cartridge which is done in the conventional SPE in a long time. In comparison to SPE, the active surface area is larger because of preventing sorbent clogging. EFs and LODs were obtained in the ranges of 831–1073 and 0.05–0.40μgL−1, respectively.