The Influence of pH on the Formation and Stability of Thaumasite

Abstract:

The samples were prepared to study the influence of pH on the formation and stability of thaumasite using Fourier transform infrared and X-ray diffraction to analyze the composition of the samples. The erosion solutions with the pH arranged from 9.5 to 13.5 prepared by sodium bicarbonate, sodium hydroxide and 5% sodium sulfate. The experimental data for three years has been given in the paper. The result of the research indicates that the value of pH at 10.5 is the optimum pH for the forming of thaumasite and when the pH comes up to 11.5, thaumastie can form but it will decompose in the solution.

• Periodical: Applied Mechanics and Materials (Volumes 174-177)
• Pages: 268-274
• DOI: https://doi.org/10.4028/www.scientific.net/AMM.174-177.268
• Online since: May 2012
• Authors: Chang Hui Yang, Ben Wan Liu, Xiao Bin Xiang, Jing Zhang
• Keywords: Formation, pH, Stability, Thaumasite

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