scholarly journals Spectrophotometric study of Solvent extraction of Pb (II) and Cd (II) by aminooctyldiphosphonic acid

F1000Research ◽  
2021 ◽  
Vol 10 ◽  
pp. 1140
Author(s):  
IKHOU Djamila ◽  
M'hamed Kaid ◽  
ZIANI Hanane ◽  
Didier Villemein

This study has investigated the solvent extraction of cadmium and lead ions from an aqueous solution in nitrate medium using aminooctyldiphosphonic acid (AODPA) as extractant in chloroform. In order to establish spectrophotometrically the concentration of metal ion in the aqueous phase before and after extraction, the Arsenazo III method was used. The effects of several extraction parameters on the extraction of these metals ions  including volume ratio between the aqueous and organic phases (1–5), extraction kinetic time (0–30 min), molar ratio Q (1–5), addition of HNO3 (pH =2–6), addition of KNO3 (0.01 – 1M), temperature (10–40°C) and the synergetic effect by adding TOPO (solvating agent) were evaluated. Thermodynamic parameters including the Gibbs free energy (ΔG0),enthalpy (ΔH0), and entropy (ΔS0) were calculated. Performed experiments showed that Pb (II) can be extracted till 73% when Cd (II) can be recovered completely after two cycles. The extraction of both metallic ions was spontaneous, endothermic and with a slight randomness.  Positive synergetic effect was observed at  a chelating agent/TOPO ratio of 3. It is a very encouraging result which can lead us to recover cadmium and lower the concentration of lead from wastewater.

2010 ◽  
Vol 7 (2) ◽  
pp. 1006-1013
Author(s):  
Baghdad Science Journal

A new Schiff base of 4- flourophenyl-4- nitrobenzyliden (L) ,was prepared and used to prepare a number of metal complexes with Cr (III) , Fe (III), Co(II) ,Ni (II) and Cu (II). These complexes were isolated and characterized by (FITR),UV-Vis spectroscopy and flame atomic absorption techniques in addition to magnetic susceptibility, and conductivity measurements. The study of the nature of the complexes formed in ethanol was done following the molar ratio method gave results, agreed with those obtained from isolated solid state studies. The antibacterial activity for the ligand and its metal complexes were examined against two selected microorganisms, Pseudomonas aeruginosa and Staphylococcus aureus.The results indicated that the complexes show the enhanced activity in comparison to the free ligand; these were attributed to the synergetic effect between the metal ion and the ligand in addition to the difference in the structural varieties.


2010 ◽  
Vol 2010 ◽  
pp. 1-6 ◽  
Author(s):  
Mehrdad Balandeh ◽  
Sirous Asgari

LiNiO2powders were synthesized with acrylic acid, citric acid, oxalic acid, and triethanolamine (TEA) as a chelating agent. CrystallizedLiNiO2was synthesized in air at a calcinations temperature of 500∘Cfor 12 hours, when the molar ratio of chelating agents to total metal ion (RPM) was 1.0. The TEA-assisted method had the highest intensity ratio of (003)/(104) peaks of X-ray diffraction (XRD) spectrum. The transmission electron microscopy (TEM) analysis indicates that the sample prepared with triethanolamine obtained the smallest particle size with average particle size of only 12 nm. The results indicate that chelating agents have an important role in the intensity ratio of (003)/(104) peaks of XRD spectrum, size and shape of powders.


1999 ◽  
Vol 52 (8) ◽  
pp. 741 ◽  
Author(s):  
Daniela Iacopino ◽  
Ledi Menabue ◽  
Monica Saladini

The interaction of MII ions (MII =Mn II, CoII, NiII, CuII, ZnII, CdII, PbII) with N-(2-nitrophenylsulfonyl)- glycine (NO2psglyH2) leads to the formation at acidic pH of the complex carboxylate-type M(NO2psgly- O)2.x H2O species. At higher pH the deprotonation reaction of the sulfonamide nitrogen takes place, leading to the formation of the M(NO2psgly-N,O).x H2O species where the ligand acts as a chelating agent toward the metal ion through the carboxylic oxygen and the deprotonated sulfonamide nitrogen. In ternary systems the addition of 2,2′-bipyridine (bpy) allows the deprotonation of the sulfonamide nitrogen also in presence of metal ions such as ZnII, CoII and NiII, which were inactive in the binary system, and the solid compounds isolated are in the M/bpy/L molar ratio 1 : 1 : 1 (MII = CuII , ZnII ) or 1 : 2 : 1(MII = CoII , NiII, CdII). Here we describe the crystal and molecular structures of NO2psglyH2 (1), [Pb(NO2psgly-N,O)]n (2), [Cd(bpy)2(NO2psgly-N,O)].H2O (3) and [Cu(bpy)(NO2psgly-N,O)(H2O)] (4).


Molecules ◽  
2022 ◽  
Vol 27 (2) ◽  
pp. 557
Author(s):  
Sergei I. Stepanov ◽  
Nguyen Thi Yen Hoa ◽  
Ekaterina V. Boyarintseva ◽  
Alexander V. Boyarintsev ◽  
Galina V. Kostikova ◽  
...  

The article presents data on the solvent extraction separation of rare-earth elements (REEs), such as La(III), Ce(III), Pr(III), and Nd(III), using synergic mixtures of methyltrioctylammonium nitrate (TOMANO3) with tri-n-butyl phosphate (TBP) from weakly acidic nitrate solutions. Specifically, experimental results on separation of REEs, for the pair Ce(III)/Pr(III) for quaternary mixtures of REEs (La(III), Ce(III), Pr(III), Nd(III)) and for the pair La(III)/Pr(III) for solutions containing La(III), Pr(III), and Nd(III), are presented. It was shown that effective separation for the pair Ce(III)/Pr(III) from a solution containing 219 g Ce(III)/L, 106 g La(III)/L, 20 g Pr(III)/L, 55 g Nd(III)/L, and 0.1 mol/L HNO3, was achieved using 56 steps of a multistage, counter-current solvent extraction cascade with scrubbing, at an organic-to-aqueous phase volume ratio (O/A) equal to 2/1 on the extraction section and O/A equal to 4/1 on the scrubbing section, using 3.3 mol/L solutions of the mixture TOMANO3-TBP with molar ratio 0.15:0.85 in dodecane. Separation for the pair La(III)/Pr(III) could be achieved using a solvent extraction cascade with scrubbing in 32 steps at O/A equal to 2/1 on the extraction section and O/A equal to 2.8/1 on the scrubbing section of the solvent extraction cascade from a solution containing 258 g La(III)/L, 58 g Pr(III)/L, 141 g Nd(III)/L, and 0.1 mol/L HNO3 with 3.0 mol/L solution of the mixture TOMANO3-TBP with molar ratio 0.2:0.8 in dodecane.


Author(s):  
Buyan-Ulzii Battulga ◽  
Tungalagtamir Bold ◽  
Enkhsaruul Byambajav

AbstractNi based catalysts supported on γ-Al2O3 that was unpromoted (Ni/γAl2O3) or promoted (Ni–Fe/γAl2O3, Ni–Co/γAl2O3, and Ni–Fe–Co/γAl2O3) were prepared using by the impregnation – co-precipitation method. Their catalytic performances for CO methanation were studied at 3 atm with a weight hourly space velocity (WHSV) of 3000 ml/g/h of syngas with a molar ratio of H2/CO = 3 and in the temperature range between 130 and 350 °C. All promoters could improve nickel distribution, and decreased its particle sizes. It was found that the Ni–Co/γAl2O3 catalyst showed the highest catalytic performance for CO methanation in a low temperature range (<250 °C). The temperatures for the 20% CO conversion over Ni–Co/γAl2O3, Ni–Fe/γAl2O3, Ni–Fe–Co/γAl2O3 and Ni/γAl2O3 catalysts were 205, 253, 263 and 270 °C, respectively. The improved catalyst distribution by the addition of cobalt promoter caused the formation of β type nickel species which had an appropriate interacting strength with alumina support in the Ni–Co/γAl2O3. Though an addition of iron promoter improved catalyst distribution, the methane selectivity was lowered due to acceleration of both CO methanation and WGS reaction with the Ni–Fe/γAl2O3. Moreover, it was found that there was no synergetic effect from the binary Fe–Co promotors in the Ni–Fe–Co/γAl2O3 on catalytic activity for CO methanation.


2005 ◽  
Vol 70 (9) ◽  
pp. 1341-1356 ◽  
Author(s):  
Saima Q. Memon ◽  
Muhammad I. Bhanger ◽  
Muhammad Y. Khuhawar

A simple and reliable method has been developed using styrene-divinylbenzene-based polymeric material containing 1-nitroso-2-naphthol as chelating agent, to concentrate ultratrace amounts of Ni(II) and Cu(II) ions in aqueous samples. Sorption of both the ions on the new synthetic resin under static and dynamic conditions has been investigated. The sorption has been optimized with respect to pH, shaking and contact time of two phases. Maximum sorption has been achieved from solution of pH 5-8 after 8 min of agitation. Total saturation capacities were 516 ± 2 and 316 ± 2.5 μmol g-1 for Ni(II) and Cu(II) ions, respectively. The lowest concentration for quantitative recovery (98 ± 1%) is 1.33 and 5 ppb with the preconcentration factor of 750 and 200 for Ni(II) and Cu(II), respectively. Monitoring of the influence of diverse ions on the sorption of metal ions has revealed that phosphate, hydrogencarbonate and citrate reduce the sorption to some extent. Under optimum conditions the sorption data followed Langmuir, Freundlich, and Dubinin-Radushkevich isotherms. The kinetics and thermodynamics of sorption are studied in detail. The sorption procedure is utilized to preconcentrate these ions prior to their determination in tea, human hair, and tap water samples by atomic absorption spectrometry using direct and standard addition methods.


1982 ◽  
Vol 152 (1) ◽  
pp. 81-88
Author(s):  
E H Berglin ◽  
M B Edlund ◽  
G K Nyberg ◽  
J Carlsson

Under anaerobic conditions an exponentially growing culture of Escherichia coli K-12 was exposed to hydrogen peroxide in the presence of various compounds. Hydrogen peroxide (0.1 mM) together with 0.1 mM L-cysteine or L-cystine killed the organisms more rapidly than 10 mM hydrogen peroxide alone. The exposure of E. coli to hydrogen peroxide in the presence of L-cysteine inhibited some of the catalase. This inhibition, however, could not fully explain the 100-fold increase in hydrogen peroxide sensitivity of the organism in the presence of L-cysteine. Of other compounds tested only some thiols potentiated the bactericidal effect of hydrogen peroxide. These thiols were effective, however, only at concentrations significantly higher than 0.1 mM. The effect of L-cysteine and L-cystine could be annihilated by the metal ion chelating agent 2,2'-bipyridyl. DNA breakage in E. coli K-12 was demonstrated under conditions where the organisms were killed by hydrogen peroxide.


Author(s):  
Vijay A. Juwar ◽  
Ajit P. Rathod

Abstract The present study deals with the treatment of complex waste (WW) treated for removal of chemical oxygen demand (COD) of the food industry by a sono-Fenton process using a batch reactor. The response surface methodology (RSM) was employed to investigate the five independent variables, such as reaction time, the molar ratio of H2O2/Fe2+, volume ratio of H2O2/WW, pH of waste, and ultrasonic density on COD removal. The experimental data was optimized. The optimization yields the conditions: Reaction time of 24 min, HP:Fe molar ratio of 2.8, HP:WW volume ratio of 1.9 ml/L, pH of 3.6 and an ultrasonic density of 1.8 W/L. The predicted value of COD was 91% and the experimental result was 90%. The composite desirability value (D) of the predicted percent of COD removal at the optimized level of variables was close to one (D = 0.991).


Clay Minerals ◽  
2018 ◽  
Vol 53 (2) ◽  
pp. 175-192 ◽  
Author(s):  
Z. Kypritidou ◽  
A. Argyraki

ABSTRACTThe retention mechanisms of metal ions during interaction of clay with metal-rich aqueous solutions is usually investigated by sorption isotherms. Although classical isotherm models may provide sufficient information about the characteristics of the solid–liquid system, they do not distinguish among the various retention mechanisms. This study presents a methodological approach of combining batch experiment data and geochemical modelling for the characterization of the interaction of Mg-Fe-rich clay materials with monometallic solutions of Pb and Cu. For this purpose, a palygorskite clay (PCM), an Fe-smectite clay (SCM) and a natural palygorskite-Fe-smectite mixed clay (MCM) were assessed for their effectiveness as metal ion sorbents. The sorption capacity of the materials follows the order MCM > SCM > PCM and ranges between 27.6–52.1 mg g–1for Pb and 7.7–17.6 mg g–1for Cu. Based on the experimental results that allowed the speciation calculations, fitting of sorption isotherms and the investigation of relationships between protons, Mg and the metals studied we suggest that a combination of sorption mechanisms occurs during the interaction of clay materials with metal solutions. These involve surface complexation, ion exchange and precipitation of solid compounds onto the solid surface. A three-term isotherm model was employed to quantify the role of each of the above mechanisms in the overall retention process. The superior performance of mixed clay among the materials tested is attributed to the synergetic effect of exchange in the interlayer and specific sorption on the clay edges.


2009 ◽  
Vol 97 (7) ◽  
Author(s):  
Claire Le Naour ◽  
M. V. Di Giandomenico ◽  
Y. Zhao ◽  
M. Mendes

AbstractSolvent extraction in the conditions of tracer scale chemistry was used to study protactinium(V) complexation with sulphate, chloride, oxalate and diethylene-triamine-pentaacetate. Extraction experiments were conducted using the chelating agent thenoyltrifluoroacetone (TTA) in toluene at constant ionic strength and temperature. Information on the species involved in partition equilibria relative to protactinium(V) complexation were deduced from a systematic study of the variations of distribution coefficient of Pa(V) as function of ligands, protons and TTA concentration.


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