共查询到20条相似文献,搜索用时 747 毫秒
1.
Piroxicam was found to be a highly selective carrier for uphill transport of Cu2+ ions through a chloroform liquid membrane. The transport occurs via a counterflow of protons from the receiving phase to
the source phase. The effects of several parameters on the transport of Cu2+ ions, such as the carrier concentration, pH of the source phase, composition of the receiving phase, and duration are described.
A high transport efficiency (98±2%) was provided by the carrier for Cu2+ ions in a receiving phase of 0.01 mol l−1 sulfuric acid after 4 h. Different metal ion transport experiments showed that Cu2+ ions were selectively transported over other ions, such as Co2+, Ni2+, Cd2+, Pb2+, Zn2+, UO22+ and ZrO22+. In the presence of fluoride ions (used as a suitable masking agent in the source phase), the interfering effects of UO22+ and ZrO22+ ions were eliminated. The applicability of the method was tested on a real sample, and the results obtained show that it
is potentially useful for solvent extraction of copper. 相似文献
2.
A method for solid phase extraction of trace metals such as Cd2+, Cr6+, Cu2+, Fe3+, Mn2+, Ni2+, Pb2+ and Zn2+ using nanometer-sized alumina coated with chromotropic acid prior to determination by inductively coupled plasma atomic emission spectrometry (ICP-AES) has been developed. Various influencing parameters on the separation and preconcentration of trace metals, pH, flow rate, sample volume, amount of adsorbent, concentration of eluent and sorption kinetics have been studied. The detection limits for Cd2+, Cr6+, Cu2+, Fe3+, Mn2+, Ni2+, Pb2+ and Zn2+ were found to be 0.14, 0.62, 0.22, 0.54, 0.27, 0.28, 0.53 and 0.38 ng ml− 1, respectively. The adsorption capacity of the solid phase adsorption material is 10.3, 11.3, 14.5, 16.4, 15.1, 11.7, 15.4 and 16.8 mg g− 1 for Cd2+, Cr6+, Cu2+, Fe3+, Mn2+, Ni2+, Pb2+ and Zn2+, respectively. The preconcentration factor was obtained in the range of 50-100 for all studied metal ions. Coexisting ions over a high concentration range have not shown any significant effects on the determination of aforesaid metal ions. The accuracy of the proposed method was tested by standard reference materials (NIST 1643e: water, NIST 1573a: tomato leaves and NIST 1568a rice flour) and natural waters and the results obtained were in good agreement with the certified values. 相似文献
3.
《Journal of membrane science》1999,157(2):171-176
The facilitated transport of Au(III) from cyanide solutions through a bulk liquid membrane is reported. The organic phase consisted of a chloroform solution containing Victoria blue dye as the Au(CN)−4 carrier. The effects of pH of source phase, potassium cyanide concentration in source phase, Victoria blue concentration in the organic phase and sodium hydroxide in the receiving phase on the efficiency of transport process were examined. Under optimum conditions the extent of Au(CN)−4 transport across the liquid membrane was about 97% after 180 min. The carrier can selectively and efficiently transport Au(CN)−4 ion from the aqueous solutions containing other cations such as alkali and alkaline earth, Zn2+, Pb2+, Cu2+, Cd2+, Hg2+, Ag+, Co2+, Fe2+, Pt2+, Pd2+ and Ni2+. 相似文献
4.
Ali Asghar Amiri Afsaneh Safavi Ali Reza Hasaninejad Hashem Shrghi Mojtaba Shamsipur 《Journal of membrane science》2008
Facilitated transport of silver ion across a supported liquid membrane (SLM) by calix[4]pyrroles, as selective ion carriers, dissolved in kerosene has been investigated. The influences of fundamental parameters affecting the transport of silver ion including ion carrier concentration in the membrane phase, thiosulfate concentration in strip phase, picric acid concentration in the feed phase, stirring speed of aqueous phases, type of membrane solvent and time of transport have been studied. In the presence of thiosulfate as a suitable metal ion acceptor in the strip phase and picrate ion as ion pairing agent in the source phase, transport of silver occurs almost quantitatively after 75 min. The selectivity and efficiency of silver transport from aqueous solution containing Cu2+, Mg2+, Ni2+, Ca2+, Zn2+, Pb2+, Co2+, Al3+, Hg2+, Cd2+, Fe3+, Fe2+ and Cr3+ were investigated. 相似文献
5.
Chemical factors such as pH, concentration and temperature affecting the removal of UO2
2+, Th4+, Fe3+, Cu2+, Pb2+,Cd2+, Ni2+, MnO4
- and phenol by Eichornia crassipes aquatic plant from their solutions were examined. Maximum uptake of ions by Eichornia crassipes occurred at pH 4 to 6±0.5 at 25±3 °C. An initial rapid uptake phase for the first 6 hours followed by a slower near linear one was observed. One gram of Eichornia crassipes can accumulate about 25 mg UO2
2+, 5 mg Th4+, 30 mg Fe3+, 10 mg MnO4
-, 15 mg Cu2+, 1.0 mg Pb2+, 1.5 mg Ni2+, 0.7 mg Cd2+ and or 25 mg of phenol. 相似文献
6.
Sayed Yahya Kazemi 《中国化学会会志》2008,55(5):1101-1106
A chloroform membrane system containing a given mixture of dibenzyldiaza‐18‐crown‐6 and palmetic acid was applied for transport of Pb2+ ions. The transport was capable of moving metal ions “uphill”. Thus, it was possible to follow the transfer of Pb(II) from the aqueous source phase to the organic layer and from the organic layer to the receiving phase. The effects of thiosulfate concentration in the receiving phase, palmetic acid and dibenzyldiaza‐18‐crown‐6 concentration in the organic phase on the efficiency of the transport system were examined. By using S2O32? ion as metal ion acceptor in the receiving phase, the amount of lead ion transport across the liquid membrane after 150 minutes is 96 ± 1.5%. The selectivity and efficiency of lead transport from aqueous solution containing Cu2+, Tl+, Ag+, Co2+, Ni2+, Mg2+, Zn2+, Hg2+, Cd2+, Ca2+ were investigated. In the presence of thiosulfate as a suitable masking agent in the source phase, the interfering effects of Ag+ and Cu2+ were diminished drastically. 相似文献
7.
Atanu Mitra 《Tetrahedron letters》2009,50(7):776-1321
A new glucose-based C2-derivatized colorimetric chemo-sensor (L1) has been synthesized by a one-step condensation of glucosamine and 2-hydroxy-1-naphthaldehyde for the recognition of transition metal ions. Among the eleven metal ions studied, viz., Mg2+, Ca2+, Mn2+, Fe2+, Fe3+, Co2+, Ni2+, Cu2+, Zn2+, Cd2+ and Hg2+, L1 results in visual colour change only in the presence of Fe2+, Fe3+and Cu2+ in methanol. However, in an aqueous HEPES buffer (pH 7.2) it is only the Fe3+ that gives a distinct visual colour change even in the presence of other metal ions, up to a concentration of 280 ppb. The changes have been explained based on the complex formed, and the composition has been determined to be 2:1 between L1 and Fe3+ based on Job’s plot as well as ESI MS. The structure of the proposed complex has been derived based on HF/6-31G calculations. 相似文献
8.
Crayfish Shell Waste as Safe Biosorbent for Removal of Cu2+ and Pb2+ from Synthetic Wastewater
下载免费PDF全文
![点击此处可从《化学物理学报(中文版)》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Crayfish shell is an abundant natural waste and is also a potential biosorbent for pollutants, especially, heavy metals. In this study, the safety of the use of crayfish shell as a biosorbent was first assessed by release experiments involving primary heavy metal ions, such as Cu2+, Zn2+, and Cr3+, in aqueous solution under different environmental conditions. The release concentrations of heavy metals were dependent on pH, ionic strength, and humic acid; and the maximum release concentrations of heavy metals were still lower than the national standard. Specifically, Cu2+ and Pb2+ removal by crayfish shell in synthetic wastewater was investigated. The removal process involved biosorption, precipitation, and complexation, and the results indicate that crayfish shell is an excellent biosorbent for Cu2+ and Pb2+ removal. The precipitation step is particularly dependent on Ca species, pH, and temperature. The maximum removal capacities of Pb2+ and Cu2+ were 676.20 and 119.98 mg/g, respectively. The related precipitates and the generated complex products include Cu2CO3(OH)2, Ca2CuO3, CuCO3, Pb2CO3(OH)2, CaPb3O4, and PbCO3. 相似文献
9.
Malihe S. Kazemi Golamhossein Rounaghi 《Russian Journal of Inorganic Chemistry》2010,55(12):1987-1991
The liquid membrane transport of Pb2+ cation using decyl-18-crown-6 as selective ion carrier was studied. The transport of lead ion across the liquid membrane in the presence of S2O 3 2? , P2O 7 4? , CN?, SCN?, and DDC? as stripping agents in the receiving phase shows that the nature and the concentration of the stripping agents affect on Pb2+ cation transport and the maximum transport occurs when the sodium thiosulfate (Na2S2O3) was used. The effects of various parameters influencing the transport efficiency such as the pH of the source and receiving phases, the concentration of picrate ion as counter ion in the source phase were also studied. Five replicated experiments show that a value 82.12 ± 2.09% of the initial concentration of the Pb2+ cation in the source phase is extracted into the receiving phase after 4 hours. Also the selectivity and efficiency of lead ion transport from the source phase containing equimolar mixtures of Na+, K+, Ca2+, Ni2+, Cu2+, Cd2+ and Ag+ metal cations were investigated. 相似文献
10.
In this work, we synthesised and characterised three novel fluorescence macrocyclic sensors containing optically active dansyl groups. The studies for the interaction of the synthesised compounds with various mental ions (Li+, Na+, K+, Ag+, Mg2+, Ca2+, Ba2+, Pb2+, Zn2+, Co2+, Cd2+, Hg2+, Ni2+, Cu2+, Mn2+, Cr3+, Al3+, Fe3+) were performed by fluorescence titration, Job’s plot, ESI-MS and DFT calculations. The results showed that the sensors 1a–1c displayed selective recognition for Cu2+ and Fe3+ ions and formed stoichiometry 1:1 complex through PET mechanism in DMSO/H2O solution (1:1, v/v, pH 7.4 of HEPES). The binding constant (K) and detection limit were calculated. 相似文献
11.
Application of Cloud Point Extraction for Copper,Nickel, Zinc and Iron Ions in Environmental Samples
A cloud point extraction procedure was presented for the preconcentration of copper, nickel, zinc and iron ions in various samples. After complexation by 2‐(6‐(1H‐benzo[d]imidazol‐2‐yl)pyridin‐2‐yl)‐1H‐benzo[d]Imidazole (BIYPYBI), analyte ions are quantitatively extracted in Triton X‐114 following centrifugation. 1.0 mol L?1 HNO3 nitric acid in methanol was added to the surfactant‐rich phase prior to its analysis by flame atomic absorption spectrometry (FAAS). The adopted concentrations for BIYPYBI, Triton X‐114 and HNO3 and bath temperature, centrifuge rate and time were optimized. Detection limits for Cu2+, Fe3+, Zn2+ and Ni2+ ions was 1.4, 2.2, 1.0 and 1.9 ng mL?1, respectively. The preconcentration factors for all ions was 30, while the enrichment factor of Cu2+, Fe3+, Zn2+ and Ni2+ ions was 35, 25, 39 and 30, respectively. The proposed procedure was applied to the analysis of real samples. 相似文献
12.
A chloroform membrane system containing dibenzodiaza‐15‐crown‐4 was found to be a highly efficient and selective transport of Ag+ ions through a chloroform liquid membrane. In the presence of thiosulfate ion as a suitable ion stripping agent in the receiving phase, the amount of silver transported across the liquid membrane after 105 minis 95 ± 1.3%. The selectivity of Ag+transport from aqueous solutions containing Tl+, Pb2+, Cd2+, Ni2+, Co2+, K+, Ca2+, Sr2+, Hg2+, Zn2+, Cu2+was investigated. The interfering effect of Cu2+ ions was drastically diminished in the presence of EDTA as a proper masking agent in the source phase. 相似文献
13.
A new ratiometric fluorescent sensor ( 1 ) for Cu2+ based on 4,4‐difluoro‐4‐bora‐3a,4a‐diaza‐s‐indacene (BODIPY) with di(2‐picolyl)amine (DPA) as ion recognition subunit has been synthesized and investigated in this work. The binding abilities of 1 towards different metal ions such as alkali and alkaline earth metal ions (Na+, K+, Mg2+, Ca2+) and other metal ions ( Ba2+, Zn2+, Cd2+, Fe2+, Fe3+, Pb2+, Ni2+, Co2+, Hg2+, Ag+) have been examined by UV‐vis and fluorescence spectroscopies. 1 displays high selectivity for Cu2+ among all test metal ions and a ~10‐fold fluorescence enhancement in I582/I558 upon excitation at visible excitation wavelength. The binding mode of 1 and Cu2+ is a 1:1 stoichiometry determined via studies of Job plot, the nonlinear fitting of the fluorometric titration and ESI mass. 相似文献
14.
A Colorimetric and Fluorimetric Chemodosimeter for Copper Ion Based on the Conversion of Dihydropyrazine to Pyrazine
下载免费PDF全文
![点击此处可从《化学:亚洲杂志》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Dr. Junbo Li Shao Chen Pian Zhang Zilong Wang Guankui Long Dr. Rakish Ganguly Dr. Yongxin Li Prof. Dr. Qichun Zhang 《化学:亚洲杂志》2016,11(1):136-140
In this research, we successfully synthesized and fully characterized the new compound 5,8,13,16,21,24‐hex‐(triisopropylsilyl)ethynyl)‐6,23‐dihydro‐6,7,14,15,22,23‐hexaza‐trianthrylene ( HHATA , brown color in a mixed solvent of CH2Cl2/CH3CN 1:1, v/v, weakly blue fluorescent), which can be easily oxidized to 5,8,13,16,21,24‐hex‐(triisopropylsilyl)ethynyl)‐6,7,14,15,22,23‐hexazatrianthrylene ( HATA ) (yellow color in CH2Cl2/CH3CN 1:1, v/v), red fluorescent) by Cu2+ ions. This reaction only proceeds efficiently in the presence of Cu2+ ions when compared with other common metal ions such as Fe3+, Co2+, Mn2+, Hg2+, Ni2+, Pb2+, Ag+, Mg2+, Ca2+, K+, Na+, and Li+. Our result suggests that this reaction can be developed as an effective method for the detection of Cu2+ ions. 相似文献
15.
M. I. Larionov E. V. Gribanova A. N. Egorov 《Russian Journal of Applied Chemistry》2015,88(11):1770-1777
Adsorption of heavy metal ions (Cu2+ and Pb2+) on various samples of a manganese-zinc nano ferrospinel of composition Mn0.7Zn0.3Fe2O4, produced by the coprecipitation method, was studied. Samples of the starting ferrospinel and that modified with zinc and obtained in the presence of thermally treated agricultural wastes of cereal crops were examined. It was shown that all the three samples are effective sorbents. It was also found that the adsorption process on these sorbents is of complex type, depending on the nature of a metal ion being sorbed. 相似文献
16.
Paunka S. Vassileva Madlena S. Apostolova Albena K. Detcheva Elisaveta H. Ivanova 《Chemical Papers》2013,67(3):342-349
Natural Bulgarian diatomite modified by oxidation with sulfuric acid and H2O2 or by coating with manganese oxide was characterized considering its chemical composition, surface area, pore volume, and structure. Modified diatomites displayed larger surface area and pore volumes in comparison with untreated natural diatomite, which favored their sorption behavior. Sorption properties of diatomites towards Fe3+, Pb2+, Cu2+, Cd2+, Mn2+, Ni2+, Co2+, Cr3+, Pd2+, Ca2+, and Mg2+ were investigated and their sorption capacities were determined. Sorption properties of manganese oxide-modified diatomite were superior to those of diatomite modified by oxidation. Owing to its high sorption capacity towards Co2+, Ni2+, Pb2+, Cr3+, Fe2+, Cu2+, and Cd2+, the manganese oxide-modified diatomite is a promising low-cost sorbent for selective removal of milligram amounts of these toxic metal ions from contaminated water. 相似文献
17.
A new dual chemosensor (TTF-PBA) for Fe3+ and Cu2+ in different signal pathways was designed and synthesized. The absorption spectrum, fluorescence spectrum and cyclic voltammograms changed in the presence of Cu2+ and Fe3+. The optical color changed within 5 s from yellow to orange upon the addition of Cu2+, and it changed to dark yellow when Fe3+ existed. The cyclic voltammogram of Cu2+/TTF-PBA changed from Eox = 0.50 V, Ered = 0.32 V to Eox = 0.64 V, Ered = 0.80 V (vs Ag/AgCl) upon the addition of 2.0 equiv. Cu2+. As for Fe3+/TTF-PBA, its oxidation wave disappeared, and its reduction wave appeared at Ered = ?0.59 V (vs Ag/AgCl) upon the addition of 4.0 equv. Fe3+. The sensor displayed high selectivity for Cu2+ and Fe3+ over other ions including Pb2+, Zn2+, Ni2+, Ag+, Cr3+, Mn2+, Al3+, Co2+, Pd2+, Hg2+, Fe2+, Cd2+, Ce3+, Bi3+ and Au3+, the detection limits for Cu2+ and Fe3+ ion reached as low as 5.33 × 10?7 mol/L and 5.34 × 10?7 mol/L, respectively. Furthermore, when Fe3+ existed, Cu2+ can be detected sequentially by the sensor through the absorption spectrum and the color change observed by naked-eyes. 相似文献
18.
《Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy》2004,60(11):2527-2530
Luminescent CdSe-ZnS quantum dots (QDs) were modified with bovine serum albumin (BSA) and used as selective copper ion probe. The fluorescence of the water-soluble QDs can be quenched only by Cu2+ and Fe3+ in physiological buffer solution. Approximate concentrations of other physiologically important cations, such as Zn2+, Na+ and K+ etc. have no effect on the fluorescence. Adding F− to form the colorless complex FeF63− can eliminate the interference of Fe3+. The detection limit of Cu2+ ions was 10 nM. The results can be explained in terms of strong binding of Cu2+ onto the surface of CdSe resulting in a chemical displacement of Cd2+ ions and the formation of CuSe on the surface of the QDs. 相似文献
19.
Application of mercapto‐silica polymerized high internal phase emulsions for the solid‐phase extraction and preconcentration of trace lead(II)
下载免费PDF全文
![点击此处可从《Journal of separation science》网站下载免费的PDF全文](/ch/ext_images/free.gif)
A new class of solid‐phase extraction column prepared with grafted mercapto‐silica polymerized high internal phase emulsion particles was used for the preconcentration of trace lead. First, mercapto‐silica polymerized high internal phase emulsion particles were synthesized by using high internal phase emulsion polymerization and carefully assembled in a polyethylene syringe column. The influences of various parameters including adsorption pH value, adsorption and desorption solvents, flow rate of the adsorption and desorption procedure were optimized, respectively, and the suitable uploading sample volumes, adsorption capacity, and reusability of solid phase extraction column were also investigated. Under the optimum conditions, Pb2+ could be preconcentrated quantitatively over a wide pH range (2.0–5.0). In the presence of foreign ions, such as Na+, K+, Ca2+, Zn2+, Mg2+, Cu2+, Fe2+, Cd2+, Cl? and NO3?, Pb2+ could be recovered successfully. The prepared solid‐phase extraction column performed with high stability and desirable durability, which allowed more than 100 replicate extractions without measurable changes of performance. The feasibility of the developed method was further validated by the extraction of Pb2+ in rice samples. At three spiked levels of 40.0, 200 and 800 μg/kg, the average recoveries for Pb2+ in rice samples ranged from 87.3 to 105.2%. 相似文献
20.
Mehrorang Ghaedi Morteza Montazerozohori Mehdi Nejati Biyareh Kianoosh Mortazavi Mostafa Soylak 《International journal of environmental analytical chemistry》2013,93(5):528-542
Multiwalled carbon nanotubes chemically functionalized with 2-((3-silylpropylimino) methyl) phenol (SPIMP-MWCNT) and successfully applied for the solid phase extraction (SPE) of some metal ions in food samples. The influences of the analytical parameters including pH, amounts of solid phase, eluent conditions (type, volume and concentrations), sample volume and interference of some metal ions on the recoveries of ions Cu2+, Pb2+, Fe2+, Ni2+ and Zn2+ ion were investigated. The metal ions retained on SPIMP-MWCNT was eluted using 6?mL of 4?mol?L?1 HNO3 solution and their content was determined by flame atomic absorption spectrometry (FAAS) with recoveries more than 95% and relative standard deviations (n?=?5) between 2.4–3.4% for both reproducibility and repeatability. The detection limit of this metal ions was between 1.0–2.6?ng?mL?1 (3S b , n?=?10) and their preconcentration factor was 100, while their loading capacity was above 32.9?mg?g?1 of SPIMP-MWCNT. The proposed method was successfully applied for the preconcentration and determination of analytes in different samples. 相似文献