Multiple effects of glycine on stability and rheology behavior of hydrated Mg(OH)₂ slurry

Abstract

Hydration of MgO is a potential technology for economically preparing Mg(OH)₂ slurry. Understanding the rheological behavior evolution of the slurry during MgO hydration, particularly in the presence of hydration agent, is essential for better control of the hydrated Mg(OH)₂ slurry’s rheology. In this work, Mg(OH)₂ slurry was prepared by hydrating MgO in the presence of glycine. The effect of glycine on the rheological behavior of the hydrated Mg(OH)₂ slurry have been investigated by means of viscosity, shear stress, sedimentation measurements, particle size distribution, ¹H nuclear magnetic resonance relaxometry and zeta potential. Results showed that shear thinning rheological slurry could be made by hydration at 80 °C for 1 h. The yield stress of the slurry is 27.49 ± 0.81 Pa, and no settling occurs within 7 days. Yet, in the absence of glycine, the structure of the slurry was unstable and easily settled even after 8 h of hydration. Glycine has multiple effects on the slurry’s solid loading, particle morphology, particle size distribution, and zeta potential of the slurry. In addition, the neutral zwitterionic form of glycine may serve as an inter-particle lubricant, reducing viscosity.

Graphical Abstract

Keywords:

• Rheology
• Stability
• Mg(OH)2 slurry
• Hydration
• Glycine

Disclosure statement

No potential conflict of interest was reported by the authors.

Data availability statement

Data will be made available on request.

Additional information

Funding

This research was financially supported by Fundamental Scientific Research Projects for the Higher Education Institutions of Liaoning Provincial Department of Education (LJKFZ20220167).