20.500.12556/DiRROS-17974 Alternative alkali activators based on waste bottle glass and waste cathode-ray tube glass Alkali-activated binders are an environmentally friendly alternative to Portland cement, particularly when locally-available raw materials are used. It is well known that alkali activation with a sodium silicate activator generates a hardened binder with higher compressive strength than a binder hardened with sodium hydroxide. As the alkali-silicate activators are produced through energy extensive processes, and their use can significantly increase the carbon footprint of the final products, it is of great significance to develop alternative alkaline activators based on locally-available waste materials. This article assesses the potential to apply waste bottle glass and waste cathode-ray tube (CRT) glass to synthesise alternative alkali activators by the hydrothermal method. Inductively coupled plasma-optical emission spectrometry (ICP-OES) was used to determine silicon and aluminium content in the alternative activators. The influence of dissolution process parameters (time, temperature, particle size) on the concentrations of silicon and aluminium in the alternative activators was investigated. The alternative activators with silicon concentration up to 19 g/L and aluminium concentration up to 0.9 g/L were prepared at T = 120 °C and boiling time 24 h. The alternative alkali activators and, for comparison, also commercial sodium silicate were used in the alkali activation of fly ash powder. The formed pastes were cured at 70 °C for 72 h. Mechanical strength measurements indicated that alkali activation of fly ash with the optimal alternative activator yielded hardened paste with compressive strength of 33 MPa. However, the compressive strength of hardened paste prepared from fly ash and commercial sodium silicate reached 70 MPa. Part of this difference can be ascribed to the lower density of hardened pastes prepared with alternative activators. alkali -activated materials alternative alkali activators waste bottle glass waste cathode -ray tube glass fly ash hydrothermal method true false true Slovenian National Building and Civil Engineering Institute Angleški jezik Ni določen © 2021 Slovenian National Building and Civil Engineering Institute, Ljubljana 2021 Neznano 2024-01-25 09:15:08 2024-01-25 09:18:07 2024-01-26 03:50:47 0000-00-00 00:00:00 2021 0 0 Nasl. z nasl. zaslona; Opis vira z dne 6. 7. 2021; Str. 93-100 0000-00-00 Zaloznikova Objavljeno NiDoloceno 0000-00-00 0000-00-00 2021-01-01 624 69350659 68189443 coms2020-21-proceedings-2-rev.pdf coms2020-21-proceedings-2-rev.pdf Odprti dostop 1 784B54F3B28983B358E004308C521C77 fb89971d4afbb139672d73408a4916b5490fd13165f8b9df8d4b10882460a02c db3ff36c-bb59-11ee-b0d4-001a4af901a5 https://dirros.openscience.si/Dokument.php?lang=slv&id=24382 RAZ_Koenig_Katja_2021.pdf RAZ_Koenig_Katja_2021.pdf 1 9C43B4CE7C61DEF8FEF6FB1CF80E21C6 34edcb2a5f991c73c6ebf551961917e3fc1be4386c2dcf57b98155534a5175a8 55a5777a-bb5a-11ee-b0d4-001a4af901a5 https://dirros.openscience.si/Dokument.php?lang=slv&id=24384 https://www.zag.si/dl/coms2020-21-proceedings-2-rev.pdf 0 4dec5709-bb5a-11ee-b0d4-001a4af901a5 https://dirros.openscience.si/Dokument.php?lang=slv&id=24383 Zavod za gradbeništvo Slovenije 0 0 0