Influence of MgO on Calcium Aluminate Slag System with Lower Calcium

Abstract:

The effect of MgO on phase composition, alumina leaching properties and the self-disintegrating rate of calcium aluminate slag were investigated by X-ray diffraction and another analysis method. And a feasible method is proposed to eliminate the negative effects of MgO. The results shows that: the phase of 2CaO·SiO₂(C₂S)、20CaO·13Al₂O₃·3MgO·3SiO₂(Q phase) and 12CaO·7Al₂O₃(C₁₂A₇) are formed when there is MgO in slag with the C/A=1.4 and A/S=1.3. The content of Q phase increase and the leaching rate of slag reduce with increasing the temperature and the content of MgO. MgO would reduce self-disintegrating rate of slag. CaSO₄·2H₂O can improve the self-disintegrating the leaching properties of slag by promoting the synthesis of C₁₂A₇ and inhibit the synthesis of Q phase.

• Periodical: Advanced Materials Research (Volumes 941-944)
• Pages: 43-47
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.941-944.43
• Online since: June 2014
• Authors: Bo Wang, Jian Xin Zhang*, Hui Lan Sun, Shu Feng Zong
• Keywords: C₁₂A₇, Calcium Aluminate Slag, Leaching Property, MgO, Q Phase, Self-Disintegrating

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