Bacteria-induced internal carbonation of reactive magnesia cement

被引：38

作者：

Xiao, Xi ^{[1
]}

Goh, Li Xuan ^{[1
]}

Unluer, Cise ^{[2
]}

Yang, En-Hua ^{[1
]}

机构：

[1] Nanyang Technol Univ, Sch Civil & Environm Engn, 50 Nanyang Ave, Singapore 639798, Singapore

[2] Univ Glasgow, Sch Engn, Glasgow G12 8LT, Lanark, Scotland

来源：

CONSTRUCTION AND BUILDING MATERIALS | 2021年 / 267卷

关键词：

MgO; Bacteria; Urea; Internal carbonation; Performance; ENHANCED HYDRATION; NITROUS-OXIDE; UREA; MGO; CONCRETE; SEQUESTRATION; OXIDATION; AMMONIA; CO2;

D O I：

10.1016/j.conbuildmat.2020.121748

中图分类号：

TU [建筑科学];

学科分类号：

0813 ;

摘要：

With lower calcination temperature, reactive magnesia cement (RMC) can be a potential alternative to the Portland cement. However, RMC concrete requires accelerated carbonation curing from external sources which greatly hinder the wider applications of RMC. This study proposed a bacteria-based method for the strength gain of RMC through internal carbonation. Sporosarcina pasteurii, urea, and yeast extract were used as a carbonation agent for internal carbonation of RMC pastes. Results showed that the flowability of the fresh bio-RMC paste increased by 20% while the initial setting time remained unchanged. Besides serving as the CO2 provider, urea can also function as superplasticizer to reduce the water demand of the bio-RMC pastes. The resulting bio-RMC pastes showed a continuous strength gain with time, demonstrating the feasibility of bacteria-induced internal carbonation of RMC. Microstructure analysis revealed abundant formation of hydrated magnesium carbonates in the bioRMC pastes, which is responsible for the strength gain of the bio-RMC pastes. (C) 2020 Elsevier Ltd. All rights reserved.

引用

页数：8

共 41 条

[1]

[Anonymous], 2013, C109C109M13 ASTM

[2]

[Anonymous], 2004, C191 ASTM

[3]

ASTM C, 2007, ASTMC1437

[4] The effect of magnesite calcination conditions on magnesia hydration [J].

Birchal, VSS ;

Rocha, SDF ;

Ciminelli, VST .

MINERALS ENGINEERING, 2000, 13 (14-15) :1629-1633

[5] Permeation properties of concrete made with fly ash and silica fume: Influence of ureolytic bacteria [J].

Chahal, Navneet ;

Siddique, Rafat .

CONSTRUCTION AND BUILDING MATERIALS, 2013, 49 :161-174

[6] Synthesis of reactive MgO from reject brine via the addition of NH4OH [J].

Dong, Haoliang ;

Unluer, Cise ;

Yang, En-Hua ;

Al-Tabbaa, Abir .

HYDROMETALLURGY, 2017, 169 :165-172

[7] Development of MgO concrete with enhanced hydration and carbonation mechanisms [J].

Dung, N. T. ;

Unluer, C. .

CEMENT AND CONCRETE RESEARCH, 2018, 103 :160-169

[8] Influence of nucleation seeding on the performance of carbonated MgO formulations [J].

Dung, N. T. ;

Unluer, C. .

CEMENT & CONCRETE COMPOSITES, 2017, 83 :1-9

[9] Sequestration of CO2 in reactive MgO cement-based mixes with enhanced hydration mechanisms [J].

Dung, N. T. ;

Unluer, C. .

CONSTRUCTION AND BUILDING MATERIALS, 2017, 143 :71-82

[10] Alternative cement clinkers [J].

Gartner, Ellis ;

Sui, Tongbo .

CEMENT AND CONCRETE RESEARCH, 2018, 114 :27-39

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