Fenton degradation of sulfanilamide in the presence of Al,Fe-pillared clay: Catalytic behavior and identification of the intermediates

[EN]Liquid phase catalytic degradation of sulfanilamide with H2O2 was carried out in the presence of Fe,Al/M-pillared clay (Fe,Al/M-MM, M = Na+, Ca2+ and Ba2+) as heterogeneous Fenton type catalyst. Fe,Al/M-MMs were prepared by swelling of layered aluminosilicate (90–95 wt.% montmorillonite) from a bed located in Mukhortala (Buryatia, Russia) in Na+, Ca2+ and Ba2+ forms by means of the exchange of these cations with bulky Fe,Al-polyoxocations prepared at Al/Fe = 10/1 and OH/(Al + Fe) = 2.0, and then calcinated at 500 °C. XRD method and chemical analysis demonstrated that the rate of crystalline swelling was dependent on the interlayer cations and decreased in the order: Fe,Al-/Na-MM > Fe,Al/Ca-MM > Fe,Al/Ba-MM. It was found that the catalytic properties of Fe,Al/M-MMs depended on the type of exchangeable cations. The effect of the H2O2/sulfanilamide molar ratio, the catalyst content, the reaction temperature and the reaction pH on the removal rate of sulfanilamide has been studied in the presence of Fe,Al/Na-MM. The catalyst can be applied for degradation of sulfanilamide with H2O2 for at least three successive cycles without loss of activity. HPLC analyses pointed out that the main degradation intermediate products were sulfanilic acid, benzenesulfonic acid, p-benzoquinone and aliphatic carboxylic acids

Evaluation of the Potential of Application of Clay from the Taryatsky Deposit in Wastewater Treatment from Basic Dyes

Изучен адсорбционный потенциал глины Тарятского месторождения в адсорбции красителя «Метиленовый синий». Кинетические закономерности адсорбции МС на глине согласуются с моделью кинетики псевдовторого порядка, а изотерма адсорбции соответствует модели Ленгмюра с максимальной величиной адсорбции 227.3 мг/г. Показано, что воздействие ультразвука способствует увеличению скорости адсорбции красителя и повышению эффективности очистки водыThe adsorption potential of natural clay from the Taryatsky deposit in the adsorption of the dye “Methylene blue” was studied. The kinetic regularities of the dye adsorption on the clay are in agreement with the pseudo-second order kinetics model, and the adsorption isotherm corresponds to the Langmuir model with a maximum adsorption value of 227.3 mg/g. It has been shown that the effect of ultrasound promotes an increase in the rate of the dye adsorption and an increase in the efficiency of water purificatio