标题：STUDIES ON SYNTHESIS AND PROPERTIES OF ALUMINUM-MAGNESIUM HYDROXIDE POSITIVE SOL
作者：HOU, WG; ZHANG, CG; SUN, DJ; LIANG, XL; WANG, GT
通讯作者地址：[HOU, WG]SHANDONG UNIV,INST COLLOID & INTERFACE CHEM,JINAN 250100,PEOPLES R CHINA.
来源：CHEMICAL JOURNAL OF CHINESE UNIVERSITIES-CHINESE
关键词：MIXED METAL HYDROXIDE; SOL; ULTRAFINE PARTICLE
摘要：A positive sol of aluminium magnesium hydroxide was synthesized by non-steady coprecipitation. The synthesis mechanism, shape, chemical composition, electrical property and thermal stability of colloidal particles were studied by X-ray diffraction, transmission electron microscope, chemical analysis, spectroanalysis and measuring of electrophoretic mobilities. The colloidal particles are tiny platelets with an average diameter of about 30 nm, and may aggregate with ''oxygen-bridge'' in water medium. In the process of synthesis, the peptization is the transformation process from amorphous to crystalline. The chemical compositions of particles are dependent od the composition of raw material. When the ratios; of Mg/Al in raw material are 1 : 2, 1 : 1 and 2 : 1, the chemical formulas of colloidal particles are Mg0.27Al(OH)(3.07)Cl-0.47. 0.86H(2)O,Mg0.43Al(OH)(3.72)Cl-0.14.(0.5)H2O, Mg0.96Al(OH)(4.50) Cl-0.42. 1.45H(2)O, respectively. The electrophoretic mobilities and thermal stability of the colloidal particles increase with increasing the content of magnesium in chemical composition of the particles.