A platform for research: civil engineering, architecture and urbanism
A platform for research: civil engineering, architecture and urbanism
Improved low-carbon magnesium oxysulfate cement pastes containing boric acid and citric acid
Abstract The dominant form of cement used worldwide is Portland cement with annual output of approximately 4 billion tons and emissions of approximately 8% of total global anthropogenic greenhouse gas emissions. One of inorganic binders being developed to relieve this negative effect relates to the use of low-carbon magnesium oxysulfate (MOS) cement. This research investigated the hydration process and mechanical properties of low-carbon MOS cement containing citric acid and boric acid. A boric acid-citric acid gel precursor is formed in MgSO4 solution, changing the hydration behavior of MOS cement due to electrostatic and steric stabilization. As a result, 3 Mg(OH)2·MgSO4·8H2O destabilizes to Mg(OH)2·MgSO4·5H2O and forms the phase 517 (5 Mg(OH)2·MgSO4·7H2O). This reduces the hydration rate of MOS cement and provides more time for the nucleation and growth of the phase 517 crystals, resulting in an optimization in pore structure and a decrease in total porosity, which improves the mechanical properties and produces a low-carbon MOS cement with characteristics that are more suitable for use in construction industry.
Improved low-carbon magnesium oxysulfate cement pastes containing boric acid and citric acid
Abstract The dominant form of cement used worldwide is Portland cement with annual output of approximately 4 billion tons and emissions of approximately 8% of total global anthropogenic greenhouse gas emissions. One of inorganic binders being developed to relieve this negative effect relates to the use of low-carbon magnesium oxysulfate (MOS) cement. This research investigated the hydration process and mechanical properties of low-carbon MOS cement containing citric acid and boric acid. A boric acid-citric acid gel precursor is formed in MgSO4 solution, changing the hydration behavior of MOS cement due to electrostatic and steric stabilization. As a result, 3 Mg(OH)2·MgSO4·8H2O destabilizes to Mg(OH)2·MgSO4·5H2O and forms the phase 517 (5 Mg(OH)2·MgSO4·7H2O). This reduces the hydration rate of MOS cement and provides more time for the nucleation and growth of the phase 517 crystals, resulting in an optimization in pore structure and a decrease in total porosity, which improves the mechanical properties and produces a low-carbon MOS cement with characteristics that are more suitable for use in construction industry.
Improved low-carbon magnesium oxysulfate cement pastes containing boric acid and citric acid
Chen, Xiaoyang (author) / Wang, Shaoyan (author) / Zhou, Yongxiang (author) / Cheeseman, Christopher (author) / Bi, Wanli (author) / Zhang, Tingting (author)
2022-10-12
Article (Journal)
Electronic Resource
English
Effects of Material Ratio, Fly Ash, and Citric Acid on Magnesium Oxysulfate Cement
| British Library Online Contents | 2014
Effects of Material Ratio, Fly Ash, and Citric Acid on Magnesium Oxysulfate Cement
| Online Contents | 2014