Пористість природного гейландиту, збагаченого міддю та цинком

• Datum: 2025
• Hauptverfasser: Tsitsishvili, V.G., Dolaberidze , N.M., Mirdzveli, N.A., Nijaradze , M.O., Amiridze , Z.S., Khutsishvili , B.T.
• Format: Artikel
• Sprache: Englisch
• Veröffentlicht: Chuiko Institute of Surface Chemistry National Academy of Sciences of Ukraine 2025
• Schlagworte: гейландит; мідь; цинк; іонний обмін; пористість
• Online Zugang: https://www.cpts.com.ua/index.php/cpts/article/view/821
• Назва журналу: Chemistry, Physics and Technology of Surface

Zeolites enriched with such “biocidal” metals as silver, copper and zinc exhibit antimicrobial activity and can be used as disinfectant filter materials and fillers. Zeolite enrichment is carried out by exchanging cations of “biocidal” metals with compensating cations under various conditions, as a result of which not only the cationic composition but also the porous structure of the zeolite changes. Enrichment of heulandite-bearing tuff from the Dzegwi-Tedzami deposit (Eastern Georgia) with Cu2+ and Zn2+ ions was carried out by treatment in solutions of the copper and zinc chlorides (“liquid” ion exchange) and by the “solid-state” ion exchange method. It has been found that “liquid” ion exchange is more effective for enriching heulandite with zinc, and as a result of ion exchange, the crystal structure of heulandite is preserved, but changes in the chemical composition of the zeolite affect its porosity. Filling of micropores with water molecules does not depend on the presence of copper and zinc ions, whereas as a result of enrichment the number of water molecules adsorbed in large pores increases significantly. The volume of micropores calculated from the low-temperature (77 K) nitrogen adsorption-desorption isotherms and the specific surface area calculated using the Brunauer-Emmett-Teller model increase as a result of enrichment. Analysis of the mesopore system using the Barret-Joyner-Halenda model shows that the average mesopore diameter increases slightly (from 17.2 to 21.5 nm), while as a result of “liquid” ion exchange, the volume of mesopores with a diameter of less than 180 nm decreases and pores with a diameter of 4 nm become predominant, whereas as a result of “solid” ion exchange, the volume of mesopores increases, and their distribution by pore size depends on the nature of the absorbed metal.