Mechanochemical route for synthesizing a (Mg-Al-NO3) form of layered double hydroxide

摘要

This paper introduces a mechanochemical process for synthesizing a nitrate compound, Mg-Al-(NO3) (Mg: Al = 3:1), which is a layered double hydroxide (LDH) from three kinds of starting samples, Mg(OH)2, A1(OH)3 and Mg(NO3)2'6H2O. The operation was attempted by one and two steps milling operations, and the former is to grind the three kinds of starting samples simultaneously, while the latter is to mill two kinds, Mg(OH)2 and Al(OH)3, followed by further milling with Mg(N03)26H2O. As a result, the latter is superior to the former in terms of the formation of the nitrate compound of LDH. The milling operation was done by using a planetary ball mill for different periods of time up to 3 hours. The ground products were characterized by XRD, FT-IR, and TG-DTA. It was confirmed that the nitrate compound of LDH was synthesized mechanochemically in the milled product within 3 hours. This form can be utilized as a fertilizer, which has ability of release control of the nitrate from it, due to the intercalation into the LDH structure.