Synthesis and Characterization of Mg-Al Layered Double Hydroxide

Abstract

Mg-Al layered double hydroxide was synthesized by the method of mechanochemistry /crystallization at the dry milling time of 6 h, wet milling time of 2 h, milling speed of 250 r/min, and ball to powder weight ratio of 50 to 1 using brucite, Al(OH)3 and Na2CO3 as the raw materials. Characterizations of the materials were achieved by XRD, TEM, FT-IR and TG-DSC. The results showed that well crystallized Mg-Al LDH with average partical size of 40 nm were synthesized under this condition. Mg-Al LDH was formed with CO32- freely intercalated between the hydroxide host layers. The material generally decomposed via two distinct stages. The first stage at 229.5 °C was attributed to the loss of interlayer water, and the second stage at 407.8°C was due to the loss of hydroxyl groups from the brucite-like layer, as well as of the carbonate irons.