Sorption of Copper(II) from Chloride Solutions by Carbonate-containing Technological Waste

Absorption of copper(II) ions from copper chloride solutions by a technological carbonate-containing waste was studied in relation to concentration of starting solutions (1-25 wt %), amount of sorbent added, and time.     

Iron(III) Removal from Aluminum Sulfate Solutions by Sorption

Russian Journal of Applied Chemistry - Sorption of aluminum(III) and iron(III) from their individual solutions and of iron(III) impurity from Al2(SO4)3 solutions on macroporous resins, Puromet...     

Sorption of Chromium(VI) from Aqueous Solutions on AM-2b Anion Exchanger

Sorption of chromium(VI) from a solution with the initial concentration of CrO₃ of up to 30 mg dm^{- 3} on a commercial macroporous AM-2b anion exchanger pretreated by various methods was studied. The optimal conditions for efficient sorption were found.     

Dynamic of Exchange Sorption of Transition Metal Ions on Phosphate Cationite KFP-12

The dynamics of ion-exchange sorption of double-charged metal ions on a phosphate cationite KFP-12 was studied. Theoretical calculations of stationary fronts were carried out, the motion velocity of the stationary fronts was calculated, and the rate constant of sorption was evaluated.     

Sorption of Gallium(III) from Alkaline Solutions with a Polymeric Sorbent Impregnated with 1,2-Dioxyanthraquinone

Distribution of Ga(III) among aqueous solutions of NaOH and a macroporous copolymer of styrene with divinylbenzene, impregnated with 1,2-dioxyanthraquinone in the presence of the trialkylmethylammonium cation, was studied.     

Complexation of Chlorodiethylenetriaminegold(III) with Chloride Ions in Aqueous Solutions

The reaction of Au(Dien)Cl²⁺ (Dien is diethylenetriamine) with the chloride ion was studied spectrophotometrically in an aqueous solution at I = 1.0 mol/l and T = 20°C. The formation constant of pentacoordinated Au(Dien)Cl ₂ ⁺ was determined and its spectrum was calculated.     

Sorption of Lanthanum(III) and Neodymium(III) from Concentrated Phosphoric Acid by Strongly Acidic Cation Exchange Resin (SQS-6)

The feasibility of using a macroporous strongly acidic cation exchange resin (SQS-6) as an adsorbent for lanthanum(III) and neodymium(III) from phosphoric acid medium, >4.0 M, was administered using batch and column techniques. Different parameters affecting the sorption of these metal ions such as v/m ratio, acid concentration and the metal ion concentration were separately investigated. The results indicated that the sorption process is relatively fast, reaching equilibrium state within 10 min. Influence of temperature on the equilibrium distribution values was also studied to evaluate the changes in standard thermodynamic quantities where the results indicated that the sorption is endothermic and the process is spontaneous associated with increasing the randomness of the system. The adsorption results of the studied metal ions were found to obey Langmuir isotherm model over the entire studied concentration range. The recovery of La(III) and Nd(III) from the loaded resin was performed with 1.0 M citric acid at pH 4.0. The breakthrough capacity of La(III) and Nd(III) was found to be 33.55 and 17.30 mg/g, respectively. The experimental data resulting from column technique were followed Thomas and Yoon-Nelson models.

     

Regeneration of Iron(III) Chloride Etching Solutions Containing Organic Additives

The behavior of inorganic macrocomponents (Fe^{3 +}, Fe^{2 +}, Cu^{2 +}, and Cl^-) and organic additives (judged from the relative concentration of total carbon) in regeneration and reuse of spent etching solutions used in fabrication of copper type-plates was studied. The conditions of electrochemical and sorption stages of the regeneration process were discussed.     

Selective Sorption of Fe(III) Ions from Ni(II)-Fe(III) Mixtures with Chemisorbents

Selective recovery of Fe(III) ions from two-component nitrate solutions of Fe(III) and Ni(II) with synthetic nickel phosphate, natural chalk, and natural tripoli were studied. The mechanism of selective action of chemisorbents was considered, and high efficiency of the materials considered was demonstrated.     

Influence of the Degree of Chitosan Sulfoethylation on the Sorption of Palladium(II) Chloride Complexes from Multicomponent Solutions

The influence exerted by the degree of substitution of sulfoethylated chitosan cross-linked with glutaraldehyde on the sorption of Pd(II) chloride complexes from multicomponent solutions containing Pt(IV), Cu(II), Ni(II), Co(II), Cd(II), and Zn(II) was studied. The sorption of transition metal ions under the conditions of the experiment at pH 0.5–5.0 is virtually fully suppressed. The strongest interfering effect on the Pd(II) sorption is exerted by Pt(IV). Calculation of the selectivity coefficients K_Pd/Pt shows that the selectivity of the Pd(II) sorption relative to Pt(IV) increases with an increase in the degree of substitution of chitosan from 0.3 to 0.5. Integral kinetic curves of the Pd(II) sorption were obtained, and the dependences were subjected to mathematical processing using the models of diffusion and chemical kinetics. The equilibrium in the palladium(II) chloride solution–sorbent system is attained within 40 min. Pd and Pt are quantitatively desorbed from the sorbent surface under dynamic conditions with 3.5 M HCl solution.     

Deoxygenation of Aqueous Solutions by Cathodically Polarized Copper-Containing Redox Cation Exchanger

Oxygen reduction in aqueous solutions by cathodically polarized copper-containing redox resins was studied. To provide reagent-free, continuous, and exhaustive deoxygenation, the rate of surface electroless oxidation with oxygen should be equal to the rate of electrochemical reduction (regeneration) of the redox centers.     

Thin Later Chbomatography of Amino Acids on Tin(IV) Arsenosilicate Cation Exchanger in Some Buffer Solutions

Abstract

Inorganic ion exchanger tin(IV) arsenosillcate (TAS) has been used in the thin layer chromatographic study of 24 amino acids in various buffer solutions as the mobile phases. On the basis of the differential movement, some important binary separations of amino acids have been achieved, particularly those of basic fro acidic or neutral amino acids.     

Synthesis and Physicochemical Characteristics of New Tetrachloroferrates(III) with Dimethylammonium Cation: X‐ray Crystal Structure of Bis(dimethylammonium) Chloride Tetrachloroferrate(III)

Two new tetrachloroferrates(III) have been synthesized of molecular formulas [(CH₃)₂NH₂][FeCl₄] and [(CH₃)₂NH₂]₂FeCl₅. The differences in their physicochemical properties have been highlighted using thermal analysis (TG‐MS) and differential scanning calorimetry (DSC). The crystal and molecular structure of [(CH₃)₂NH]₂FeCl₅ was determined. The iron(III) cation is four coordinated by chloride ions, and it adopts a slightly distorted tetrahedral coordination with three angles smaller and three larger than the tetrahedral one. In the structure four intermolecular N‐H···Cl hydrogen bonds link the [(CH₃)₂NH₂]⁺ cations to dimers via a Cl^? bridge.     

Synthesis and Sorption Behaviour of Some Radioactive Nuclides on Sodium Titanate as Cation Exchanger

Crystalline (Na₄TiO₄·0.32H₂O) and amorphous (Na₂TiO₃·1.45H₂O) forms of sodium titanate were prepared by fusion reaction of TiO₂ and Na₂CO₃ at 1100°C in molar ratios of 2:1 and 1:2, respectively. The prepared products were characterized using IR, DTA-TG, X-ray and elemental analyses. Kinetic studies of the order of reaction (n) and activation energy (E _a) for crystallization transformation step (for crystalline sodium titanate only) have been determined from DTA thermogram and their values were found to be 0.87 (univalent order) and 3.97 kJ mol^–1, respectively. Ion exchange capacities and some distribution studies were carried out at different conditions in the presence of some complexing agents (EDTA, boric and citric acids) and the results showed that the capacities of the crystalline form are always less than the amorphous one.     

Sorption Purification of Scandium(III) To Remove Zirconium(IV) Impurity in Hydrochloric Acid Solutions

A study was made on separation of the Zr(IV) impurity from scandium(III) in hydrochloric acid solutions by sorption with KRF-20t-60 cation exchanger, including sorption kinetics and sorption under dynamic conditions. The sorbent regeneration with 5% ammonium fluoride or 10% potassium carbonate at 22°C was considered.     

Cation Exchange and Sorption Properties of TIN(IV) Phosphate

The ion exchange and sorption properties of crystalline Tin bis(monohydrogen orthophosphate) monohydrate of composition Sn(HPO(4))(2).H(2)O were studied in an aqueous solution of KCl over the temperature range 300-320 K, varying the pH and metal ion concentration in the solution. The data were explained on the basis of the law of chemical equilibrium. The metal ion sorption data were fitted to the Langmuir adsorption equation to evaluate the Langmuir parameters. The extent of adsorption was found to increase with an increase in temperature and metal ion concentration in the selectivity order Cu(2+)>Co(2+)>Ni(2+). The Langmuir parameters were used to calculate the thermodynamic functions like standard entropy, enthalpy, and free energy changes during the process of sorption. Copyright 2000 Academic Press.     

Sorption of Lead(II) from Aqueous Solutions by Synthetic Zeolites

A comparative study of the sorption of lead(II) from dilute aqueous solutions by synthetic faujasites, chabazites, mordenites, erionites, phillipsites, and type A zeolites was performed. The most promising sorbents are low-silica chabazites and potassium erionites with relatively high SiO₂/Al₂O₃ ratio.     

Recovery of Thorium(IV) and Radium(II) from Chloride Solutions

Recovery of thorium(IV) and radium(II) by precipitation methods in the chloride technology of perovskite processing was studied.     

Synthesis and Sorption Performance of Novel Sorbents for Selective Solid-Phase Extraction of Eu(III) Ions from Aqueous Solutions

Russian Journal of Applied Chemistry - Magnesium-cadmium hydroxyapatite [(Mg-Cd)HAP] and novel multi-wall carbon nanotubes Mg-Cd hydroxyapatite (CNTs/(Mg-Cd)HAP) composites were synthesized by a...