TY - JOUR

T1 - Acid-based geopolymers using waste fired brick and different metakaolins as raw materials

AU - Bewa, Christelle N.

AU - Tchakouté, Hervé K.

AU - Banenzoué, Charles

AU - Cakanou, Lorette

AU - Mbakop, Theophile T.

AU - Kamseu, Elie

AU - Rüscher, Claus H.

N1 - Funding information: Dr. Tchakouté Kouamo Hervé gratefully acknowledges the Alexander von Humboldt-Stiftung for its financial support this work under grant N ° KAM/1155741 GFHERMES-P . The authors would like to thank Dr. Valerie Petrov for SEM observations and Dr. Ricarda Behrens for XRF analysis performed.

PY - 2020/11/15

Y1 - 2020/11/15

N2 - Three metakaolins and waste fired brick were used to explore the effects of iron oxide, amorphous silica and quartz in the raw materials on the compressive strength and the microstructural properties of acid-based geopolymers cured at room temperature and 60 °C. Quartz content in the metakaolin from Dibamba is about 22.0 wt% and each other samples contain around 8.0 wt%. Waste fired brick and metakaolin from Bangoua contain nanocrystalline hematite and have higher amorphous silica content. The higher quartz content in the metakaolin from Dibamba could prevent the incorporation of PO4 units in the networks. The compressive strengths of the acid-based geopolymers cured at room temperature are higher (35.3–56.4 MPa) compared to those cured at 60 °C (17.8–32.9 MPa). The higher amorphous silica and nanocrystalline hematite content in the starting materials could accelerate the hardening process. It can be concluded that iron oxide, amorphous silica and quartz in the starting material could affect the compressive strengths of acid-based geopolymers.

AB - Three metakaolins and waste fired brick were used to explore the effects of iron oxide, amorphous silica and quartz in the raw materials on the compressive strength and the microstructural properties of acid-based geopolymers cured at room temperature and 60 °C. Quartz content in the metakaolin from Dibamba is about 22.0 wt% and each other samples contain around 8.0 wt%. Waste fired brick and metakaolin from Bangoua contain nanocrystalline hematite and have higher amorphous silica content. The higher quartz content in the metakaolin from Dibamba could prevent the incorporation of PO4 units in the networks. The compressive strengths of the acid-based geopolymers cured at room temperature are higher (35.3–56.4 MPa) compared to those cured at 60 °C (17.8–32.9 MPa). The higher amorphous silica and nanocrystalline hematite content in the starting materials could accelerate the hardening process. It can be concluded that iron oxide, amorphous silica and quartz in the starting material could affect the compressive strengths of acid-based geopolymers.

KW - Acid-based geopolymers

KW - Amorphous silica

KW - Iron oxide

KW - Metakaolins

KW - Quartz

KW - Waste fired brick

UR - http://www.scopus.com/inward/record.url?scp=85089702032&partnerID=8YFLogxK

U2 - 10.1016/j.clay.2020.105813

DO - 10.1016/j.clay.2020.105813

M3 - Article

AN - SCOPUS:85089702032

VL - 198

JO - Applied clay science

JF - Applied clay science

SN - 0169-1317

M1 - 105813

ER -