Effect of SiO2, Al2O3 and Na2O content and fly ash fineness on the structure and mechanical properties of fly ash based geopolymer

Roland Szabó; Gábor Mucsi

doi:10.5937/ror1901061S

Autori

Roland Szabó University of Miskolc, Institute of Raw Material Preparation and Environmental Processing, Miskolc, Hungary Author https://orcid.org/0000-0002-4536-7610
Gábor Mucsi University of Miskolc, Institute of Raw Material Preparation and Environmental Processing, Miskolc, Hungary Author https://orcid.org/0000-0003-1031-2801

DOI:

https://doi.org/10.5937/ror1901061S

Ključne reči:

lebdeći pepeo, metakaolin, geopolimer, mehanička aktivacija, SiO2/Al2O3 molarni odnos, SiO2/Na2O molarni odnos, Al2O3/Na2O molarni odnos

Apstrakt

U današnje vreme, tehnologije geopolimera na bazi sekundarnih sirovina se sve više koriste. Međutim, neke od njih (na primer na bazi lebdećeg pepela) imaju na početku nisku reaktivnost koja se može promeniti mehaničkom ili hemijskom aktivacijom, kao i dodavanjem različitih visoko reaktivnih materijala. U ovom radu je ispitivan uticaj sadržaja silicijum, aluminijum i natrijum oksida na strukturu i mehaničke osobine geopolimera na bazi lebdećeg pepela sa visokim sadržajem kalcijuma. Metakaolin (MK) je korišćen kao dodatni izvor aluminijuma i silicijuma. Dodavan je u različitim dozama (0; 5; 10; 15; 25; 50 i 75% mase) kao zamena za lebdeći pepeo. Rezultati eksperimenta potvrđuju da na pritisnu čvrstoću geopolimera značajno utiče odnos SiO2/Al2O3, Al2O3/Na2O i SiO2/Na2O. Dodavanje metakaolina je povećalo pritisnu čvrstoću geopolimera za 92%. Osim toga, ispitivan je i uticaj mehaničke aktivacije lebdećeg pepela na strukturu i čvrstoću geopolimera u zavisnosti od sadržaja metakaolina. Na osnovu dobijenih rezultata, može se zaključiti da se mehaničkom aktivacijom lebdećeg pepela postigla veća pritisna čvrstoća. Dodavanje metakaolina i finoća lebdećeg pepela su promenili strukturu geopolimera, što je utvrđeno metodom FT-IR spektroskopije.

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