Ispitivanje adsorpcionih svojstava elektrofilterskog pepela sa deponije termoelektrane „Moravaˮ u odnosu na fosfat-jone prisutne u rastvoru

Abstract

In this study we prepared adsorbents on the basis of clinoptilolite-rich zeolitic tuff (Slanci deposit, Beograd), and chitosan, as well as partially cross-linked chitosan by glutaraldehyde. We investigated removal rate of nickel and zinc ions from the aqueous solution by both adsorbents at 25 °C, adsorption isotherms, adsorption kinetics, regeneration of spent adsorbents and their antibacterial activity. Removal rate of both adsorbents for both studied cations was significantly increased in comparison to unmodified clinoptilolite. The adsorption isotherm for Ni (II) followed the Langmuir model, while isotherm for Zn was in accord with the the Freundlich equation. Adsorption kinetics followed the Lagergren pseudo-second order kinetic model for both adsorbents and cations. The adsorbents can be regenerated to a large extent after use. Unlike unmodified clinoptilolite-based adsorbents, spent adsorbents did not show antibacterial activity. This was ascribed to interactions between chitosan coating and clinoptilolite.

U radu su pripremljeni adsorbensi na bazi zeolitskog tufa bogatog klinoptilolitom (ležište Slanci, Beograd) i hitozana, kao i hitozana koji je delimično umrežen glutaraldehidom. Ispitana je efikasnost uklanjanja jona nikla i cinka iz vodenog rastvora pomoću oba adsorbensa na 25 oC, adsorpcione izoterme, kinetika adsorpcije, regeneracija istrošenih adsorbenasa i njihova antibakterijska aktivnost. Efikasnost uklanjanja oba ispitivana katjona značajno se povećava nakon modifikacije. Adsorpciona izoterma Ni(II) sledi Langmirovu, dok Zn(II) Frojndlihovu izotermu. Kinetika adsorpcije odgovara Lagergrenovom modelu pseudodrugog reda. Oba adsorbensa se mogu u velikom stepenu regenerisati nakon upotrebe. Istrošeni adsorbensi, za razliku od nemodifikovanog klinotpilolita, ne pokazuju antibakterijsku aktivnost. Ovo je pripisano interakcijama hitozana sa klinoptilolitom