METHOD FOR PREPARING HYDROTALCITE-LIKE COMPOUNDS USING UREA

摘要

PURPOSE: A method for preparing hydrotalcite-like compounds using urea is provided, thereby preparing hydrotalcite-like compounds having improved crystalline structure in higher yield. CONSTITUTION: A method for preparing hydrotalcite-like compounds of the formula 1 of £M(II)1-xM(III)x(OH)2|¬x+(NO3)xmH2O using urea comprises dissolving a hydrate of M(II) metal nitride of the formula 2 of M(II)(NO3)2.m1H2O and a hydrate of M(III) metal nitride of the formula 3 of M(II)(NO3)3.m2H2O in water with adding urea and carrying out the hydrothermal reaction of them, wherein M(II) is divalent metal cation; M(III) is trivalent metal cation; X is 0.1 to 0.5; m, m1 and m2 represent the number of water molecules; the divalent metal cation is selected from Mg2+, Zn2+ and Ni2+; the trivalent metal cation is Al3+; the amount of urea added is 0.5 to 5 times as large as NO3-; and the hydrothermal reaction is carried out at 80 to 120 deg. C for 5 to 15 hours.