A method for producing mesoporous magnesium hydroxide nanoplates involving solvothermal treatment of a solution of a magnesium salt, a base, a glycol, and water is disclosed. The method does not use a surfactant or template in the solvothermal treatment. The method yields mesoporous nanoparticles of magnesium hydroxide having a plate-like morphology with a diameter of 20 nm to 100 nm, a mean pore diameter of 2 to 10 nm, a surface area of 50 to 70 m.sup.2/g, and a type-III nitrogen adsorption-desorption BET isotherm with a H3 hysteresis loop. An antibacterial composition containing the mesoporous magnesium hydroxide nanoplates is also disclosed. A method for reducing nitroaromatic compounds with a reducing agent and the mesoporous magnesium hydroxide nanoplates as a catalyst is also disclosed.

A process for the chemical conversion of contaminated magnesium hydroxide to high purity solutions of magnesium bicarbonate include steps of providing an impure reagent including at least 40% and less than 95% by total weight of total metals of magnesium in a form of solid magnesium hydroxide and at least 10% by weight of total metals of calcium carbonate, combining the impure reagent containing the solid magnesium hydroxide with carbonic acid in water, thereby generating magnesium bicarbonate and water and then filtering out solid calcium carbonate leaving a solution of magnesium bicarbonate in water having a by weight ratio of Mg/(Mg+Ca) in the solution of greater than 95%. Heating and/or drying the magnesium bicarbonate solution produces correspondingly high purity magnesium carbonate.

A process for the chemical conversion of contaminated magnesium hydroxide to high purity solutions of magnesium bicarbonate include steps of providing an impure reagent including at least 40% and less than 95% by total weight of total metals of magnesium in a form of solid magnesium hydroxide and at least 10% by weight of total metals of calcium carbonate, combining the impure reagent containing the solid magnesium hydroxide with carbonic acid in water, thereby generating magnesium bicarbonate and water and then filtering out solid calcium carbonate leaving a solution of magnesium bicarbonate in water having a by weight ratio of Mg/(Mg+Ca) in the solution of greater than 95%. Heating and/or drying the magnesium bicarbonate solution produces correspondingly high purity magnesium carbonate.

Divalent ions are extracted from solids by leaching to form a divalent ion-containing solution. The divalent ion-containing solution is subjected to concentration to form a concentrated divalent ion-containing solution. Precipitation of a divalent ion hydroxide salt is induced from the concentrated divalent ion-containing solution. In other cases, the concentrated divalent ion-containing solution is exposed to carbon dioxide to induce precipitation of a divalent ion carbonate salt.

Divalent ions are extracted from solids by leaching to form a divalent ion-containing solution. The divalent ion-containing solution is subjected to concentration to form a concentrated divalent ion-containing solution. Precipitation of a divalent ion hydroxide salt is induced from the concentrated divalent ion-containing solution. In other cases, the concentrated divalent ion-containing solution is exposed to carbon dioxide to induce precipitation of a divalent ion carbonate salt.

This magnesium oxide powder contains secondary particles in which a plurality of primary particles of magnesium oxide having a crystal phase and a grain boundary phase are at least partially fused together by the grain boundary phase, and a median diameter obtained by a laser diffraction scattering method is 300 .Math.m or less.

Provided are magnesium oxide particles which are good in dispersibility in a resin or rubber, can function sufficiently as an acid acceptor or scorch retarder, and do not lower, even after combined with a resin or rubber, material properties thereof; a resin composition; a rubber composition; and a shaped body. The magnesium oxide particles satisfying the following (A) to (C): (A) an average particle size is 5 μm or less; (B) a BET specific surface area is 20 m.sup.2/g or more and 200 m.sup.2/g or less; and (C) a screen residue by a sieve opening of 45 μm is 0.1% by weight or less.

Provided are magnesium oxide particles which are good in dispersibility in a resin or rubber, can function sufficiently as an acid acceptor or scorch retarder, and do not lower, even after combined with a resin or rubber, material properties thereof; a resin composition; a rubber composition; and a shaped body. The magnesium oxide particles satisfying the following (A) to (C): (A) an average particle size is 5 μm or less; (B) a BET specific surface area is 20 m.sup.2/g or more and 200 m.sup.2/g or less; and (C) a screen residue by a sieve opening of 45 μm is 0.1% by weight or less.

The present invention relates to a getter composition comprising magnesium oxide particle doped with alkali metal, a getter layer comprising the same, and an organic electronic device comprising the getter layer. The getter composition comprising magnesium oxide particle doped with alkali metal according to the present invention has remarkably improved hygroscopicity simultaneously with maintaining transparency of the previously used magnesium oxide particles, and thus, is used in a getter layer comprising the same and an organic electronic device comprising the getter layer, thereby effectively protecting water sensitive devices.

The present invention relates to a getter composition comprising magnesium oxide particle doped with alkali metal, a getter layer comprising the same, and an organic electronic device comprising the getter layer. The getter composition comprising magnesium oxide particle doped with alkali metal according to the present invention has remarkably improved hygroscopicity simultaneously with maintaining transparency of the previously used magnesium oxide particles, and thus, is used in a getter layer comprising the same and an organic electronic device comprising the getter layer, thereby effectively protecting water sensitive devices.