Abstract
A magnesium-aluminum double hydroxide was prepared by the simultaneous hydrolysis of magnesium and aluminum alkoxides. Pure double hydroxide is obtained between 0.6 and 0.8 in the Mg 2+/(Mg 2+ + Al 3+) mole ratio. Infrared spectra were compared with those of 4Mg(OH) 2·Al(OH) 3 synthesized by Feitknecht and Gerber, and the naturally occurring mineral Mg 6Al 2(OH) 18·4H 2O. The compounds MgO and MgAl 2O 4 crystallize slowly above ≈ 500°C and ≈ 800°C, respectively. Powders for the double hydroxide gave large aggregates of small particles. Definite signs of particle growth and a marked increase in crystallite growth were seen in powders produced above 1100°C. Specific surface areas of powders heated at low temperatures are very high and did not fall below 10 m 2/g until the heating temperature was raised above 1100°C.
Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
