Yaneva Z.Koumanova B.Georgieva N.2024-07-102024-07-102024-07-102024-07-102012-01-011857-56251857-555210.20450/mjcce.2012.61SCOPUS_ID:84864535599https://rlib.uctm.edu/handle/123456789/250The adsorption behavior of 2-nitrophenol (2-NP) and 2,4-dinitrophenol (2,4-DNP) on expanded perlite (EP) at equilibrium and kinetic conditions was investigated. The experimental equilibrium data were interpreted by Langmuir, Freundlich, Redlich-Peterson, Temkin and the multilayer isotherm models. Both the Temkin and the multilayer models gave the most satisfactory representation of the experimental data for 2-NP sorption on EP covering the whole concentration range, presuming high initial sorption rate, presence of adsorbent-adsorbate chemical interactions and multilayer adsorption, as the basic characteristics featuring the equilibrium behavior of the system studied. The experimental kinetic results were analyzed by the pseudo-first, pseudo-second order models, Bangham's model, intra-particle diffusion model, and Elovich kinetic equation. The values of the calculated rate, mass transfer parameters and correlation coefficients proved that chemisorptions/intraparticle diffusion could be outlined as the basic rate controlling mechanisms during 2-NP/2,4-DNP sorption on expanded perlite. Uptake of nitrophenols increased in the order 2-NP < 2,4-DNP.enArticle