The effect of the presence of metatartaric acid on removal effectiveness of heavy metal ions on chelating ion exchangers.

The paper presents experimental results and their evaluation for the sorption of copper(II), zinc(II), cobalt(II) and nickel(II) complexes with metatartaric acid on chelating ion exchangers with different functional groups. The literature lacks the data concerning sorption of heavy metal ions in the presence of metatartaric acid on ion exchangers. The effect of important parameters such as the value of pH, the metal(II) ion and ligand concentration as well as their molar ratio and the type of functional group of the ion exchanger used was studied. It was found that the time of 60 min was sufficient for sorption to attain equilibrium. The equilibrium sorption capacities for copper(II), zinc(II), cobalt(II) and nickel(II) complexes with metatartaric acid were 37.35 mg/g, 32.02 mg/g, 32.78 mg/g and 28.31 mg/g on Lewatit TP 207 and 42.15 mg/g, 34.32 mg/g, 27.76 mg/g and 21.70 mg/g on Lewatit TP 260, respectively. The sorption optimum pH was 7. Temperature does not affect the sorption process significantly. The sorption data were well fitted by the Langmuir adsorption model whereas kinetics of the sorption process was well described by the pseudo second order kinetics equation.

Sorption of heavy metal metatartrate complexes on polystyrene anion exchangers.

The performance of polystyrene anion exchangers in purifying wastewaters containing metatartaric acid and heavy metal ions (especially those from electroless plating processes) was investigated. The following anion exchangers were selected: Lewatit MonoPlus M 500, Lewatit MonoPlus MP 64, Lewatit MP 62 and Amberlite IRA 402. A batch method was used to study the influence of: phase contact time (1-120 min); solution pH (2-9); concentration of initial heavy metal Cu(II), Zn(II), Co(II) and Ni(II) complexes (1.25 x 10(-4) M to 8.0 x 10(-3) M); temperature (303-333K); and interfering ions (Cl-, NO3-, SO4(2-), Ca2+, Mg2+). The amounts of Cu(II), Zn(II), Co(II) and Ni(II) complexes with metatartaric acid sorbed at equilibrium using the strongly basic anion exchanger Lewatit MonoPlus M 500 were equal to 7.25 mg/g, 3.21 mg/g, 3.78 mg/g and 3.98 mg/g, respectively. The equilibrium sorption capacity increased slightly with increasing temperature. The optimal pH sorption was found to be 6.5. The experimental data were analysed using the Langmuir and Freundlich models. The maximum adsorption capacities q(0) determined from the Langmuir adsorption equation equal to 7.53 mg/g, 3.75 mg/g, 3.55 mg/g and 4.60 mg/g were in good agreement with the experimental values for Lewatit MonoPlus M 500. The kinetic data obtained at different concentrations were modelled using pseudo first order, pseudo second order and intraparticle diffusion equations. The experimental data were well described by the pseudo second order kinetic model.

Development of New Effective Sorbents Based on Nanomagnetite.

Magnetic hybrid nanocomposite material based on the kraft lignin was prepared by the co-precipitating method. Kraft lignin was modified by iron nanooxide in order to enhance its sorption properties towards heavy metal ions. The composite material was characterized by physicochemical methods such as BET N2, ATR-FTIR, TGA, DSC, pHpzc, XRD and SEM. Its adsorption behaviour was studied using the batch mode by varying different parameters like pH, initial concentration of metal ions and shaking time as well as the presence of interfering ions. Adsorption of Cu(II), Cd(II) and Pb(II) ions from the aqueous solutions was studied in comparison with the commercial kraft lignin. The adsorption capacity and kinetic sorption characteristics of the composite material were determined.