Naslov
Determination of heavy metal cations affinity towards natural zeolite doped with iron sulfides particles

Autori
Barišić, Ivona ; Jurić, Antonija ; Ugrina, Marin

Vrsta, podvrsta i kategorija rada
Sažeci sa skupova, sažetak, znanstveni

Izvornik
Book of Abstracts of the 4th International Conference of Scientists, Professionals, and Students on the Topic of Environmental Protection in the Republic of Croatia / Sedlar, Jelena ; Alešković, Luka Marijan ; Nižić, Katarina ; Ćorić, Mislav - Split : Kemijsko-tehnološki fakultet u Splitu, 2023, 2-2

ISBN
978-953-7803-20-9

Skup
4th International Conference of Scientists, Professionals, and Students on the Topic of Environmental Protection in the Republic of Croatia

Mjesto i datum
Split, Hrvatska, 20.04.2023. - 21.04.2023

Vrsta sudjelovanja
Poster

Vrsta recenzije
Međunarodna recenzija

Ključne riječi
natural zeolite, modified zeolite, heavy metals, ionic affinity

Sažetak
Removal of mercury from polluted water or soil systems using sorption remediation techniques requires a high affinity of mercury toward sorbents. It is known that sulfide minerals, among which iron sulfides predominate, are mainly mercury scavengers in nature since mercury has a pronounced affinity for sulfur species, forming sparingly soluble HgS. Therefore, for the remediation of mercury- contaminated systems, it is desirable to use environmentally-friendly and easy available materials that contain sulfur. Since natural zeolites (NZ) as environmentally acceptable materials do not contain sulfur, it is necessary to carry out a suitable chemical modification in order to obtain high selectivity towards mercury. Thus, the first aim of this paper was to produce NZ doped with iron sulfide particles. For these purposes, a two-stage modification of the NZ was performed according to the procedure described by Schwartzman and Cornell [1] and Liu et. all [2]. Briefly, the 1 g of NZ was refluxed for 48 h at 90 °C with 50 mL of 1 mol/L Fe(NO)3∙9H2O at pH=8.5, and then for 4 h at 150 °C with 10 mL of 1 mol/L Na2S∙9H2O. Physicochemical characterization (chemical composition, SEM- EDS) revealed an increase in the content of Fe by 2.1-fold and sulfur by 3.2-fold, confirming the deposition of iron sulfides species on the surface of natural zeolite. The second aim was to determine the affinity of different metal cations to the prepared sorbent. For this reason, one-component (Hg, Cu, Zn, Cd, Mn, Ni, Co, Pb), two-component (Hg - Cu, Zn, Cd, Mn, Ni, Co, Pb) and multi- component solutions (Hg, Cu, Zn, Cd, Mn, Ni, Co, Pb) were prepared in which individual concentration of each metal cation was 2 mmol/L. To prevent the precipitation of metal cations, especially mercury, the experiments were carried out at pHo=2. Regardless of the complexity of the system (one-, two- or multi- component), the following affinity was determined: Hg>Pb>Cd>Cu>Zn>Ni>Co>Mn. The percentage of mercury removed in the one-component system was 97%, in the two- component systems 62-95%, while in the multi-component system 56%. The results showed an extremely high removal percentage of mercury compared to other tested heavy metal cations. This is due to the highest affinity of mercury towards sulfur species according to the hard and soft acids and bases theory, as well as the lower solubility product constant of HgS compared to other metal sulfides. Ultimately, the produced NZ doped with iron sulfides particles could be a promising sorbent for the remediation of mercury- contaminated systems.

Izvorni jezik
Engleski

Znanstvena područja
Kemijsko inženjerstvo

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