Electrooxidation of p-nitrophenol on tmabentonite modified electrodes

A natural bentonite, modified with tetramethylammonium (TMA), was used as an electrode material in a p-nitrophenol (p-NP) electrooxidation. The influence of TMA loading into the bentonite layers on the electrochemical properties TMAbentonite (TMA-B) electrodes toward p-NP electrooxidation was examined. Electrode sensitivity toward p-NP was performed. The detection limit of 1⋅10-8 mol dm-3 was obtained

Influence of HDTMA/bentonite ratio on phenol electrooxidation

Partial and complete substitution of cations in the interlayer region of clay with different amounts of hexadecyl trimethylammonium bromide (HDTMABr) was performed. We investigated the influence of HDTMA/bentonite ratio on phenol electrooxidation. Multisweep cyclic voltammetry was applied to analyze the behavior of clay modified glassy carbon electrode. The influence of phenol concentration was investigated. The reaction order in respect to phenol was determined to be around

Methanol electrooxidation from alkaline solution on pt and PtRu modified Zeolite X

Zeolite NaX was modified by Pt and Pt/Ru nanodispersed metallic clusters. This modification was achieved by zeolite impregnation with acetylacetonate salt/acetone solution, followed by acetone evaporation and thermal decomposition of organometallic complex. The mixture of modified zeolite and 10 wt.% of carbon black, in a form of thin layer, was pasted to a glassy carbon surface by nafion. Electrocatalytic properties of metal-modified zeolites were tested in methanol electrooxidation reaction

Dynamic instability of methanol oxidation from alkaline solution on stationary Pt electrode

Cyclic voltammetry (CV) was used to study the dynamic instability of electrochemical oxidation of methanol in alkaline solution at stationary platinum electrode. Methanol oxidation was carried out in bicarbonate, carbonate and different pH values of sodium hydroxide solution. Experiments were conducted with and without previous stabilization of the working electrode in alkaline solution

p-Nitrophenol Electro-oxidation on BTMA- bentonite Modified Electrode

A glassy carbon electrode (GCE) was modified with thin layer of Na-enriched bentonite and a series of benzyltrimethylammonium (BTMA)- bentonites with different BTMA/bentonite ratios. The aim was to investigate electrochemical behavior of synthesized BTMA-bentonites and to correlate it with the textural properties. The organo-bentonites were characterized using X-ray diffraction, Fourier transform infrared spectroscopy and nitrogen adsorption-desorption method

Organo-composite Ceramics: Synthesis and Application

The synthesis of organo-bentonites (OBs) obtained by modification with quaternery alkyl ammonium cations (QAACs), their characterization and evaluation of their efficiency as adsorbents for organic and inorganic aqueous pollutants was investigated. In this work starting material was bentonite clay from Bogovina, Serbia, with particle diameters of up to 74µm. The amount of incorporated QAACs corresponded to 0.0, 0.2, 0.5, 1.0 and 2.0 CEC value of the clay. The phase composition, textural and morphological properties of starting material and OB samples were determined by XRD and IR analyses, N2 physisorption and SEM microscopy

Oxidation of hydroxide ions at platinum modified zeolite electrode

NaX zeolite was modified by platinum via impregnation/thermal decomposition technique, using Pt(II)-acetylacetonate in acetone as an impregnating solution. The samples were characterized by scanning electron microscopy. The mixture of modified zeolite and 10 wt. % of carbon black, in a form of thin layer, was pasted to a glassy carbon surface by nafion. The hydroxide ion oxidation was studied on this electrode by cyclic voltammetry. The response of modified zeolite electrodes was compared with platinum electrode, bare and covered with nafion film. The presence of nafion improved reproducibility of both covered platinum electrode and platinum modifed zeolite electrode

The influence of Fe content in Al,Fe-pillared clays on its performance in catalytic wet oxidation

In this work a series of Al,Fe-pillared clays (PILCs) with different Fe3+ content was synthesized and characterized. Their catalytic performance was studied in the in catalytic wet peroxide oxidation (CWPO) of food dye tartrazine used as a model compound. Degree of decolorization of tartrazine containing aqueous solution was monitored in relation to Fe3+ content. The results of the catalytic tests showed that higher Fe content leads to higher catalyst efficiency in the investigated reaction. The reaction can be described by 0-order kinetics inherent to heterogeneous catalytic processes

Al, Fe-pillared Clay in Catalytic Wet Peroxide Oxidation of Azo Dyes: the Influence of Dye Structure

Bentonite clay from “Bogovina” (Serbia) was pillared with Al3+ and Fe3+ pillaring cations. Iron to aluminium content in the pillaring solution was adjusted to be [Fe3+/(Al3+ + Fe3+)]×100=15%. Obtained pillared clay (denoted as AlFe15 PILC) was characterized and used as catalyst in the catalytic wet peroxide oxidation (CWPO) of Tartrazine and Acid Yellow 99 azo dyes. The effect of initial dye concentration, ranging from 10–50 ppm, was studied on the example of Tartrazine. On the basis of obtained results the initial reaction order was estimated. The conversion after 4 h reached 99.8% in the most diluted Tartrazine solution at 60°C. The efficiency of the conversion of Acid Yellow 99 on AlFe15 PILC by CWPO was tested, and the results were compared. It was shown that the rate of conversion of Acid Yellow 99 was much higher. Complete decolorization in the case of 25 ppm solution of Acid Yellow 99 was achieved after 1 h. Correlation between structural properties of the dyes and their removal efficiency was proposed

Carbon monoxide electrooxidation on Pt and PtRu modified zeolite X

Zeolite NaX was modified by Pt and Pt/Ru nanodispersed metallic clusters. This modification was achieved by zeolite impregnation with acetylacetonate salt/acetone solution, followed by acetone evaporation and thermal decomposition of organometallic complex. Samples characterization was performed by X-ray diffraction analysis, nitrogen adsorption-desorption measurements and Raman spectroscopy. The incorporation of metal into zeolite cavities induced the amorphisation of the zeolite framework on the local level. The mixture of modified zeolite and 10 wt% of carbon black, in a form of thin layer, was pasted to a glassy carbon surface by Nafion. Electrocatalytic properties of metal-modified zeolites were tested in CO electrooxidation reaction. The mutual influence between Pt and Ru atoms enhanced electroactivity of Pt/Ru-modified zeolite toward carbon monoxide electrooxidation. The behavior of untreated 13X zeolite was investigated under the same condition in order to asses the influence of the support. Gradual deactivation of 13X electrode occurred