TY - JOUR

T1 - Improvement of the reactivity of soda–lime–silica glass solution as a hardener for producing geopolymer materials

AU - Melele, Sorelle J.K.

AU - Banenzoué, Charles

AU - Fotio, Daniel

AU - Tchakouté, Hervé K.

AU - Rüscher, Claus H.

AU - Nanseu-Njiki, C. P.

N1 - Funding information: Hervé K. Tchakouté gratefully acknowledges the Alexander von Humboldt Foundation for financial support this work under the Grant No. KAM/1155741 GFHERMES-P. The authors would like to thank Mr. Valerie Petrov for SEM observation.

PY - 2019/10

Y1 - 2019/10

N2 - Abstract: The aiming target of this study is to improve the reactivity of the soda–lime–silica glass solution as a hardener for producing metakaolin-based geopolymer cements. The hardeners with molar ratios SiO2/Na2O equal to 1.5 from rice husk ash and waste glass were prepared. Due to the low dissolution of waste glass, the molar ratio SiO2/Na2O in soda–lime–silica glass solution is less than 1.5 suggesting thus the lower soluble silica content. In order to compensate for the deficiency of soluble silica in soda–lime–silica glass solution, the hardener from rice husk ash is added to the soda–lime–silica glass solution at different percentage such as 0, 20, 30, 40, 50, 60, 70, 80 and 100 wt%. The reactivity of the obtained hardeners was evaluated by using them for producing geopolymer cements. The X-ray pattern and infrared spectrum of residual waste glass indicate the higher intensity of the broad hump structure and the higher value of the wavenumber of the main band, respectively. This corresponds to the higher amount of glass phase contained in the residual waste glass. It was found that the values of the compressive strengths and the apparent density increase with increasing the addition of hardener from rice husk ash to the one from waste glass. The micrographs of geopolymer cements from hardeners containing 40, 50 and 100 wt% of sodium waterglass from rice husk ash are homogeneous and compact microstructure. This implies the formation of the higher connectivity and the long chain of poly(sialate-siloxo) network. The new approach for the preparation of a reactive hardener from the waste glass is found promising for the significant reduction of the greenhouse gas emitted during the production of geopolymers. Graphic abstract: [Figure not available: see fulltext.].

AB - Abstract: The aiming target of this study is to improve the reactivity of the soda–lime–silica glass solution as a hardener for producing metakaolin-based geopolymer cements. The hardeners with molar ratios SiO2/Na2O equal to 1.5 from rice husk ash and waste glass were prepared. Due to the low dissolution of waste glass, the molar ratio SiO2/Na2O in soda–lime–silica glass solution is less than 1.5 suggesting thus the lower soluble silica content. In order to compensate for the deficiency of soluble silica in soda–lime–silica glass solution, the hardener from rice husk ash is added to the soda–lime–silica glass solution at different percentage such as 0, 20, 30, 40, 50, 60, 70, 80 and 100 wt%. The reactivity of the obtained hardeners was evaluated by using them for producing geopolymer cements. The X-ray pattern and infrared spectrum of residual waste glass indicate the higher intensity of the broad hump structure and the higher value of the wavenumber of the main band, respectively. This corresponds to the higher amount of glass phase contained in the residual waste glass. It was found that the values of the compressive strengths and the apparent density increase with increasing the addition of hardener from rice husk ash to the one from waste glass. The micrographs of geopolymer cements from hardeners containing 40, 50 and 100 wt% of sodium waterglass from rice husk ash are homogeneous and compact microstructure. This implies the formation of the higher connectivity and the long chain of poly(sialate-siloxo) network. The new approach for the preparation of a reactive hardener from the waste glass is found promising for the significant reduction of the greenhouse gas emitted during the production of geopolymers. Graphic abstract: [Figure not available: see fulltext.].

KW - Apparent density

KW - Geopolymers

KW - Hardeners

KW - Microstructure

KW - Rice husk ash

KW - Waste glass

UR - http://www.scopus.com/inward/record.url?scp=85096219518&partnerID=8YFLogxK

U2 - 10.1007/s42452-019-1242-5

DO - 10.1007/s42452-019-1242-5

M3 - Article

AN - SCOPUS:85096219518

VL - 1

JO - SN Applied Sciences

JF - SN Applied Sciences

IS - 10

M1 - 1208

ER -