Magnesium hydroxide with high purity and uniform particle size distribution was synthesized by the direct precipitation method using MgCl_(2) and NaOH as reactive materials and NaCl as additive to improve the crystall...Magnesium hydroxide with high purity and uniform particle size distribution was synthesized by the direct precipitation method using MgCl_(2) and NaOH as reactive materials and NaCl as additive to improve the crystallization behavior of the product.The particle size distribution,crystal phase,morphology,and surface area of magnesium hydroxide were characterized by Malvern laser particle size analyzer,X-ray diffraction(XRD),scanning electron microscope(SEM)and Branauer-Emmett-Teller(BET)method,respectively.The purity of products was analyzed by the chemical method.The effects of synthesis conditions on the particle size distribution and water content(filtration cake)of magnesium hydroxide were investigated.The results indicated that feeding mode and rate,and reaction temperature had important effects on water content and the particle size distribution of the product,and sodium chloride improved the crystallization behavior of magnesium hydroxide.The ball-like magne-sium hydroxides with the particle size distribution of 6.0–30.0μm and purity higher than 99.0%were obtained.This simple and mild synthesis method was promising to be scaled up for the industrial production of magnesium hydroxide.展开更多
基金supported by the Shanghai Natural Science Foundation(No.09ZR147900)the Program for New Century Excellent Talents in University(NCET-08-0776).
文摘Magnesium hydroxide with high purity and uniform particle size distribution was synthesized by the direct precipitation method using MgCl_(2) and NaOH as reactive materials and NaCl as additive to improve the crystallization behavior of the product.The particle size distribution,crystal phase,morphology,and surface area of magnesium hydroxide were characterized by Malvern laser particle size analyzer,X-ray diffraction(XRD),scanning electron microscope(SEM)and Branauer-Emmett-Teller(BET)method,respectively.The purity of products was analyzed by the chemical method.The effects of synthesis conditions on the particle size distribution and water content(filtration cake)of magnesium hydroxide were investigated.The results indicated that feeding mode and rate,and reaction temperature had important effects on water content and the particle size distribution of the product,and sodium chloride improved the crystallization behavior of magnesium hydroxide.The ball-like magne-sium hydroxides with the particle size distribution of 6.0–30.0μm and purity higher than 99.0%were obtained.This simple and mild synthesis method was promising to be scaled up for the industrial production of magnesium hydroxide.