Abstract
The present study investigated the recovery of brucite from reject brine using different precipitating agents (ethanolamine, ammonium hydroxide, calcium oxide, and sodium hydroxide) and differences in their mechanical properties due to direct carbonation. The strength development was studied using compacted pellets of brucite powders synthesized using different precipitating agents and subjected to carbonation under 20% CO2 and 80% RH at 30 ℃ conditions. Brucite powders synthesized using different precipitating agents showed differences in their micro-structural properties, affecting the type and amount of binding hydrated magnesium carbonate (HMC) phases and compressive strength. The compressive strength of the carbonated pellets was found to be in the range of 19-33 MPa for different brucite powders suitable for non-structural applications. Data from thermogravimetry (TG) and X-ray diffraction (XRD) measurements revealed that different types and amounts of HMC phases could be formed in brucite powders synthesized using different precipitating agents, which could lead to the observed difference in their compressive strength. The results from this study are significant to better optimize the compressive strength of brucite recovered from reject brine.
Original language | English (US) |
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Title of host publication | The 16th International Congress on the Chemistry of Cement 2023 (ICCC2023) |
Subtitle of host publication | Further Reduction of CO2 -Emissions and Circularity in the Cement and Concrete Industry |
Place of Publication | Bangkok |
Chapter | Vol 2 |
Pages | 120-124 |
Volume | 2 |
State | Published - Sep 18 2023 |
Keywords
- Reject brine
- precipitating agent
- accelerated carbonation
- compressive strength
- sustainable construction materials