Electrochemical degradation of the antibiotic ciprofloxacin in a flow reactor using distinct BDD anodes: Reaction kinetics, identification and toxicity of the degradation products.

The performances of distinct BDD anodes (boron doping of 100, 500 and 2500 ppm, with sp/sp carbon ratios of 215, 325, and 284, respectively) in the electrochemical degradation of ciprofloxacin - CIP (0.5 L of 50 mg L in 0.10 M NaSO, at 25 °C) were comparatively assessed using a recirculating flow system with a filter-press reactor.

Optimization of the electrochemical degradation process of the antibiotic ciprofloxacin using a double-sided β-PbO anode in a flow reactor: kinetics, identification of oxidation intermediates and toxicity evaluation.

The electrochemical degradation of ciprofloxacin-CIP (50 mg L in 0.10 mol L NaSO) was investigated using a double-sided Ti-Pt/β-PbO anode in a filter-press flow reactor, with identification of oxidation intermediates and follow-up of antimicrobial activity against Escherichia coli. The effect of solution pH, flow rate, current density, and temperature on the CIP removal rate was evaluated.

Electrodegradation of the Acid Green 28 dye using Ti/β-PbO2 and Ti-Pt/β-PbO2 anodes.

The statistical Response Surface Methodology (RSM) is applied to investigate the effect of different parameters (current density, j, NaCl concentration, [NaCl], pH, and temperature, θ) and their interactions on the electrochemical degradation of the Acid Green (AG) 28 dye using a Ti/β-PbO2 or Ti-Pt/β-PbO2 anode in a filter-press reactor. LC/MS is employed to identify intermediate compounds. For both anodes, the best experimental conditions are j = 50 mA cm(-2), [NaCl] = 1.

Electrochemical mineralization of the azo dye Acid Red 29 (Chromotrope 2R) by photoelectro-Fenton process.

The degradation of 100 mL of 244 mg L(-1) of the azo dye Acid Red 29 (AR29) has been studied by photoelectro-Fenton (PEF) using an undivided cell containing a boron-doped diamond (BDD) anode and an air-diffusion cathode under UVA irradiation. The effect of current density, concentration of catalytic Fe(2+) and pH on the process was examined. Quick decolorization and almost total mineralization were achieved due to the synergistic action of UVA light and oxidant hydroxyl radicals formed in the bulk from Fenton's reaction between electrogenerated H(2)O(2) at the cathode and added Fe(2+), as well as in the BDD surface from water oxidation.

Solar photoelectro-Fenton degradation of the herbicide 4-chloro-2-methylphenoxyacetic acid optimized by response surface methodology.

A central composite rotatable design and response surface methodology (RSM) were used to optimize the experimental variables of the solar photoelectro-Fenton (SPEF) treatment of the herbicide 4-chloro-2-methylphenoxyacetic acid (MCPA). The experiments were made with a flow plant containing a Pt/air-diffusion reactor coupled to a solar compound parabolic collector (CPC) under recirculation of 10 L of 186 mg L(-1) MCPA solutions in 0.05 M Na(2)SO(4) at a liquid flow rate of 180 L h(-1) with an average UV irradiation intensity of about 32 Wm(-2).

Electrochemical degradation of a real textile effluent using boron-doped diamond or β-PbO2 as anode.

Constant current electrolyses are carried out in a filter-press reactor using a boron-doped diamond (Nb/BDD) or a Ti-Pt/β-PbO(2) anode, varying current density (j) and temperature. The degradation of the real textile effluent is followed by its decolorization and chemical oxygen demand (COD) abatement. The effect of adding NaCl (1.

Preparation and characterization of biomimetically and electrochemically deposited hydroxyapatite coatings on micro-arc oxidized Ti-13Nb-13Zr.

Surface properties and corrosion resistance analyses of Ti-13Nb-13Zr coated by an oxide film (obtained by micro-arc oxidation at 300 V) or an oxide/hydroxyapatite (HA) film are reported. HA films were biomimetically or electrochemically deposited on the alloy/oxide surface, and their properties compared. Both the biomimetic and the electrochemical method yielded rough and globular apatite surfaces (10-20 μm globules for the former and 1-2 μm for the latter).

Voltammetric performance and application of a sensor for sodium ions constructed with layered birnessite-type manganese oxide.

The preparation and electrochemical characterization of a carbon paste electrode modified with layered birnessite-type manganese oxide for use as a sodium sensor is described. The effects of powder synthesis process (sol-gel and redox precipitation) for birnessite on the electrochemical activity of the sensor was investigated by cyclic voltammetry. The carbon paste electrode modified with birnessite-type manganese oxide that was synthesized by the sol-gel method showed a best electrochemical for sodium ions.

An Electrochemical Sensor Based on Nanostructured Hollandite-type Manganese Oxide for Detection of Potassium Ions.

The participation of cations in redox reactions of manganese oxides provides an opportunity for development of chemical sensors for non-electroactive ions. A sensor based on a nanostructured hollandite-type manganese oxide was investigated for voltammetric detection of potassium ions. The detection is based on the measurement of anodic current generated by oxidation of Mn(III) to Mn(IV) at the surface of the electrode and the subsequent extraction of the potassium ions into the hollandite structure.

Influence of hydroxyapatite on the corrosion resistance of the Ti-13Nb-13Zr alloy.

Electrochemical analyses on the biocompatible alloy Ti-13Nb-13Zr wt% in an electrolyte simulating physiological medium (PBS solution) are reported. Hydroxyapatite (HA) films were obtained on the alloy by electrodeposition at constant cathodic current. Samples of the alloy covered with an anodic-oxide film or an anodic-oxide/HA film were analyzed by open circuit potential and electrochemical impedance spectroscopy measurements during 180 days in the PBS electrolyte.

Voltammetric determination of L-dopa using an electrode modified with trinuclear ruthenium ammine complex (Ru-red) supported on Y-type zeolite.

The L-dopa is the immediate precursor of the neurotransmitter dopamine. Unlike dopamine, L-dopa easily enters the central nervous system and is used in the treatment of Parkinson's disease. A sensitive and selective method is presented for the voltammetric determination of L-dopa in pharmaceutical formulations using a carbon paste electrode modified with trinuclear ruthenium ammine complex [(NH(3))(5)Ru(III)ORu(IV)(NH(3))(4)ORu(III)(NH(3))(5)](6+) (Ru-red) incorporated in NaY zeolite.

Lithium ions determination by selective pre-concentration and differential pulse anodic stripping voltammetry using a carbon paste electrode modified with a spinel-type manganese oxide.

The use of selective pre-concentration and differential pulse anodic stripping voltammetry (DPASV) using a carbon paste electrode modified (CPEM) with spinel-type manganese oxide has been proposed for the determination of lithium ions content in natural waters. The new procedure is based on the effective pre-concentration of lithium ions on the electrode surface containing spinel-type Mn(IV) oxide with the reduction of Mn(IV) to Mn(III) and consequently the lithium ions intercalation (insertion) into the spinel structure. The best DPASV response was reached for an electrode composition of 25% (m/m) spinel-type MnO(2) in the paste, 0.

Degradation of phenol using Co- and Co,F-doped PbO(2) anodes in electrochemical filter-press cells.

A comparative study on the electrooxidation of phenol in H(2)SO(4) medium using pure PbO(2) or F-, Co- and Co,F-doped PbO(2) electrodes in filter-press cells was carried out. The oxide films were obtained by galvanostatic electrodeposition using an electrolytic bath containing sodium lauryl sulfate as additive and Pb(2+), F(-), Co(2+) or Co(2+)+F(-), under magnetic stirring (to obtain 4-cm(2) electrodes) or ultrasound waves (to obtain 63-cm(2) electrodes). The best results were attained with PbO(2) electrodes doped with a low-Co content (1mM Co(2+) in the electrolytic bath) along with F(-): the chemical oxygen demand (COD) and the total organic carbon content (TOC) of the simulated wastewaters were removed by about 75% and 50%, respectively.

On the performance of Fe and Fe,F doped Ti-Pt/PbO2 electrodes in the electrooxidation of the Blue Reactive 19 dye in simulated textile wastewater.

The electrochemical performance of pure Ti-Pt/beta-PbO2 electrodes, or doped with Fe and F (together or separately), in the oxidation of simulated wastewaters containing the Blue Reactive 19 dye (BR-19), using a filter-press reactor, was investigated and then compared with that of a boron-doped diamond electrode supported on a niobium substrate (Nb/BDD). The electrooxidation of the dye simulated wastewater (volume of 0.1 l, with a BR-19 initial concentration of 25 mg l(-1)) was carried out under the following conditions: current density of 50 mA cm(-2), volume flow rate of 2.

Electrochemical studies on zirconium and its biocompatible alloys Ti-50Zr at.% and Zr-2.5Nb wt.% in simulated physiologic media.

Different electrochemical studies were carried out for Zr and its biocompatible alloys Ti-50Zr at.% and Zr-2.5Nb wt.

Differential pulse anodic voltammetric determination of lithium ions in pharmaceutical formulations using a carbon paste electrode modified with spinel-type manganese oxide.

The use of the differential pulse voltammetry for the determination of lithium ions in pharmaceutical samples using a carbon paste electrode modified with spinel-type manganese oxide has been examined. The best voltammetric response was reached for a modified electrode in borate buffer solution of pH 9.0 and submitted to a scan rate of 5 mV s(-1) and a pulse amplitude of 50 mV.