POROUS SILICA PARTICLES

To provide porous silica materials with large pore sizes and high pore volume, and an improved and simpler method for preparing the same.SOLUTION: There is provided a method for producing a porous silica, comprising the step of mixing together an aqueous phase comprising nanoparticulate silica and an organic phase to form a water-in-oil dispersion or emulsion, in which the organic phase comprises an organic solvent that is insoluble or partially soluble in water and optionally comprises a non-polar organic compound that is insoluble in water and at least partially soluble in the organic solvent, and a gelling agent is present in the aqueous phase such that the nanoparticulate silica gets gelatinized to form the porous silica. There is obtained a porous silica having an average pore diameter in a range of 20 to 450 Å, a pore volume in a range of 0.15 to 1.2 cm3 g-1, a surface area in a range of 100 to 600 m2 g-1, and a span of 0.80 or less.SELECTED DRAWING: Figure 4 【課題】大きな細孔サイズおよび大きな細孔容積を有する多孔質シリカ材料、及びそれを調製するための、改善されたより単純な方法を提供する。【解決手段】ナノ粒子状シリカを含む水相と有機相とが互いに混合して油中水型分散液またはエマルジョンを形成し、有機相が、水に不溶性または部分的に溶解性である有機溶媒を含み、水に不溶性かつ有機溶媒に少なくとも部分的に溶解性である非極性有機化合物も任意選択で含み、ナノ粒子状シリカがゲル化して多孔質シリカを形成するように水相中にゲル化剤が存在する、多孔質シリカを生成する方法である。２０〜４５０Åの範囲内の平均細孔直径、０．１５〜１．２ｃｍ３ｇ−１の範囲内の細孔容積、１００〜６００ｍ２ｇ−１の範囲内の表面積、および０．８０以下のスパンを有する多孔質シリカを得る。【選択図】図４