Uçucu Kül ve Kalsiyum Alüminat Çimentosu Katkılı Pomza Esaslı Geopolimer Harçların Sülfürik Asit Direnci

Year 2022, Volume: 12 Issue: 4, 2302 - 2312, 01.12.2022

Cemal Karaaslan , Engin Yener , Tamer Bağatur , Rıza Polat , Rüstem Gül

https://doi.org/10.21597/jist.1144388

Abstract

Bu çalışmada, uçucu kül ve/veya kalsiyum alüminat çimentosu ağırlıkça toplam toz bağlayıcının %10, 20 ve 30’u kadar pomza ile ikame edilerek pomza esaslı geopolimer (PGP) harçlar üretilmiştir. Ortam sıcaklığı ve 60 °C’de kür edilen bu harçlar, 28. günde %5 derişime sahip sülfürik asit (H2SO4) çözeltisine konularak 120 gün bekletilmiştir. PGP numunelerde sülfürik asit etkisiyle oluşan görsel değişim, ağırlık kaybı ve kalan basınç dayanımı, 60 ve 120. günde ölçülmüş ve Portland Çimentosu esaslı referans harçla kıyaslanmıştır. Çalışma, referans numunelerinin sülfürik asit ortamında çözünerek 60 günün sonunda %25.6 ağırlık kaybı yaşadığını buna karşılık %20 ve 30 oranında kalsiyum alüminat çimentosu içeren karışımların ortam sıcaklığında kür edilmiş numuneleri hariç PGP harçlarda (görsel açıdan) bir çözünme olmadığını göstermiştir. Ayrıca ortam sıcaklığı ve 60 °C’de kür edilen PGP numunelerin 120 günün sonunda sırasıyla en fazla %6.5 ve 4.1 ağırlık kaybına uğradıkları tespit edilmiştir. PGP harçlar, sülfürik asit çözeltisinde 120 günün sonunda %70’e varan basınç dayanım kayıpları yaşamıştır. Ancak yeterli miktarda uçucu kül ve kalsiyum alüminat çimentosu ikamesi ile PGP harçların basınç dayanımı önemli derecede arttığı gibi sülfürik asit direnci de iyileşmiştir

Keywords

Geopolimer, pomza, uçucu kül, kalsiyum alüminat çimentosu, ısıl kür, sülfürik asit direnci

Supporting Institution

Iğdır Üniversitesi Bilimsel Araştırma Projeleri Koordinasyon Birimi

Project Number

MÜF0720A17

Sulfuric Acid Resistance of Pumice Based Geopolymer Mortars with Fly Ash and Calcium Aluminate Cement Additives

Abstract

In this study, pumice based geopolymer (PGP) mortars were produced by replacing 10, 20, and 30 wt.% of the pumice with fly ash and/or calcium aluminate cement. After curing at ambient temperature and 60 °C, the mortars were placed in a 5% sulfuric acid (H2SO4) solution on the 28th day and kept for 120 days. The change in appearance, weight loss and residual compressive strength of the PGP samples due to the effect of sulfuric acid were determined on the 60th and 120th days and compared with the Portland Cement based reference mortar. The study showed that the reference samples underwent a weight loss of 25.6% at the end of 60 days by dissolving of hardened cement paste in the sulfuric acid medium. However, it was observed that the PGP mortars did not undergo any visual change in sulfuric acid solution, except for the samples containing 20 and 30% calcium aluminate cement (for ambient curing). In addition, it was determined that the PGP samples cured at ambient temperature and 60 °C had a maximum weight loss of 6.5% and 4.1, respectively, at the end of 120 days. PGP mortars underwent compressive strength losses of up to 70% in the 120-day sulfuric acid solution. However, with sufficient fly ash and calcium aluminate cement substitution, the compressive strength of PGP mortars increased significantly as well as the sulfuric acid resistance.

Keywords

Geopolymer, pumice, fly ash, calcium aluminate cement, heat curing, sulfuric acid resistance

Project Number

MÜF0720A17

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