Rezumat
CZU 544.723.2:546.824-31:547.97
https://doi.org/10.52577/eom.2023.59.3.46
Studies on the kinetics of adsorption of methylene blue dye (MB) from an aqueous solution on a DDT photocatalyst (nanoscale titanium dioxide in the anatase phase deposited on diatomite) and its components – diatomite D and anatase TiO2 are presented. The effect of the initial concentration and pH of the MB solution on the adsorption process rate is investigated. The kinetic adsorption data were processed using two simplified kinetic models – of the pseudo-first and pseudo-second order. A model of the kinetics of intraparticle diffusion was used to study the adsorption mechanism. It was found that the kinetics of adsorption of methylene blue on the surface of D, TiO2 and DDT is best described by a pseudo-second order model. It is shown that the adsorption of methylene blue on D and DDT is a multistage process with adsorption on the outer surface and inside the particles, and the controlling stage is a chemical reaction, for TiO2 – external diffusion.
Keywords: nanoscale TiO2, diatomite, methylene blue, kinetics, adsorption mechanism.