Abstract: Highly dispersive Mg（OH）₂ nanoplates were synthesized from industrial Mg（OH）2  agglomerates via sintering- hydration method.The influence of solution composition in the hydration step on the morphology and dispersion of Mg（OH）₂  nanoplates was studied.Experimental results indicated that taking MgCl2 solution with 1 mol/L as the hydration medium could promote the dissolution and recrystallization of Mg（OH）₂，and it was also in favor of the formation of uniform and well-dis-persed Mg（OH）₂  nanoplates.Meanwhile，the addition of sodium dodecyl sulfate led to the decrease of the zeta potential of Mg（OH）₂，which inhibited the aggregation，leading to formation of high?鄄dispersive Mg（OH）₂  nanoplates with diameter at 0.5~0.8 μm and agglomerate size in 3.3 μm.

Key words: magnesium hydroxide；sintering, hydration media；surfactants；dispersion