Titanium Dioxide Nanomaterials: Synthesis, Properties, Modifications, and Applications

Application of low-cost adsorbents for dye removal – A review

: The unpolarized absorption and circular dichroism spectra of the fundamental vibrational transitions of the chiral molecule, 4-methyl-2-oxetanone, are calculated ab initio. Harmonic force fields are obtained using Density Functional Theory (DFT), MP2, and SCF methodologies and a 5S4P2D/3S2P (TZ2P) basis set. DFT calculations use the Local Spin Density Approximation (LSDA), BLYP, and Becke3LYP (B3LYP) density functionals. Mid-IR spectra predicted using LSDA, BLYP, and B3LYP force fields are of significantly different quality, the B3LYP force field yielding spectra in clearly superior, and overall excellent, agreement with experiment. The MP2 force field yields spectra in slightly worse agreement with experiment than the B3LYP force field. The SCF force field yields spectra in poor agreement with experiment.The basis set dependence of B3LYP force fields is also explored: the 6-31G* and TZ2P basis sets give very similar results while the 3-21G basis set yields spectra in substantially worse agreements with experiment. jg

Ab initio calculation of vibrational absorption and circular dichroism spectra using density functional force fields

Über die Adsorption in Lösungen

A kinetics and thermodynamics study of methylene blue adsorption on wheat shells

Copper, chromium and nickel removal from metal plating wastewater by electrocoagulation

In this study photocatalytic degradation of phenol in the presence of UV irradiated TiO2 catalyst and H2O2 was investigated Effects of TiO2 and H2O2 concentrations and pH on photocatalytic degradation were examined The rate constants for photocatalytic degradation were evaluated as a function of TiO2 and H2O2 concentrations and pH of the solution It was found that photodegradation is an effective method for the removal of phenol and disappearance of phenol obeyed first order kinetics The amount of CO2 produced during photocatalytic degradation was corresponding to the complete mineralization Photodegradation can be an alternative method for the treatment of phenol containing wastewaters

Photocatalytic degradation of phenol.

Copper (Cu), chromium (Cr), and nickel (Ni) removal from metal plating wastewater by electrocoagulation and chemical coagulation was investigated. Chemical coagulation was performed using either aluminum sulfate or ferric chloride, whereas electrocoagulation was done in an electrolytic cell using aluminum or iron electrodes. By chemical coagulation, Cu-, Cr-, and Ni-removal of 99.9 % was achieved with aluminum sulfate and ferric chloride dosages of 500, 1000, and 2000 mg L ―1 , respectively. Removal of metals by electrocoagulation was affected by the electrode material, wastewater pH, current density, number of electrodes, and electrocoagulation time. Electrocoagulation with iron electrodes at a current density of 10 mA cm ―2 , electrocoagulation time of 20 min, and pH 3.0 resulted in 99.9 % Cu-, 99.9 % Cr-, and 98 % Ni-removal.

Comparison of Electrocoagulation and Chemical Coagulation for Heavy Metal Removal

The adsorption of methylene blue and crystal violet on pumice powder samples of varying compositions was investigated using a batch adsorption technique. The effects of various experimental parameters, such as adsorbent dosage, initial dye concentration, and contact time, were also investigated. The extent of dye removal increased with decreased initial concentration of the dye and also increased with increased contact time and amount of adsorbent used. Adsorption data were modeled using the Freundlich adsorption isotherm. The adsorption kinetic of methylene blue and crystal violet could be described by the pseudo-second-order reaction model.

Feryal Akbal

Papers

Copper, chromium and nickel removal from metal plating wastewater by electrocoagulation

Photocatalytic degradation of phenol.

Comparison of Electrocoagulation and Chemical Coagulation for Heavy Metal Removal

Adsorption of basic dyes from aqueous solution onto pumice powder.

Comparison of Fenton and electro-Fenton processes for oxidation of phenol