Каталітичні властивості поліетерсульфонових мембран, модифікованих наночастинками SnO2

• Дата: 2019
• Автори: Kolesnyk, I. S., Dzhodzhyk, O. Ya., Konovalova, V. V., Sorokin, H. A., Meshkova, T. H., Burban, A. F., Tsaryk, S. M.
• Формат: Стаття
• Мова: Українська
• Опубліковано: Chuiko Institute of Surface Chemistry National Academy of Sciences of Ukraine 2019
• Теми: поліетерсульфонова мембрана; станум(IV) оксид; метод «layer-by-layer»; родамін Ж; фотокаталіз
• Онлайн доступ: https://www.cpts.com.ua/index.php/cpts/article/view/502
• Назва журналу: Chemistry, Physics and Technology of Surface

The present study aims to obtain membranes with photocatalytic properties by means of tin(IV) oxide immobilization on their surface to prevent fouling. Polyethersulfone membranes have been modified by polyelectrolyte complexes and SnO2 nanoparticles by “layer-by-layer” method. Trans-cinnamic and hydrocinnamic acids have been grafted to the surface of the membranes by the amide bond formation. Modification of membranes by nanoparticles has been confirmed by methods of scanning electron microscopy, energy dispersion spectroscopy and electrokinetic analysis. All membranes have been characterized by isoelectic point in the range of pH 4.5–5.0, positive zeta-potential in acid medium and negative one in alkaline medium. The adsorption, photocatalytic and transport properties of the membranes have been investigated using Rhodamine G. It has been shown that the immobilization of the nanoparticles of the tin(IV) oxide reduces the adsorption of the dye on the surface of the membranes twofold. It has been confirmed that membrane modification leads to the appearance of photocatalytic properties. Thus, membranes with nanoparticles of tin(IV) oxide are characterized by a high degree of dye decomposition of 40–50 % during 1.5 h the initial concentration of Rhodamine G of 1.2·10–3 %. Kinetics of dye decomposition could be described by pseudo-first rate according to an Langmuir-Hinshelwood equation. It has been found that the grafting of trans- and hydrocinnamic acids affects the pH optimum of membranes photocatalytic activity. Notably, the highest photocatalytic activity of membrane with immobilized SnO2 nanoparticles is observed in an acidic media at pH 3.0, while after trans- and hydrocinnamic acids grafting the pH optimum is shifted to alkaline and neutral media (pH 9.0 and 7.0), respectively. It has been shown that modified membranes exhibit stable flux in the process of dye nanofiltration and high levels of its rejection (70–90 %).