The Preparation Of Small Spherical Mesoporous SBA-16 Particles

Mesoporous materials are one species of inorganic material, which have been obtained by means of the corporative interaction between inorganic precursors and super-molecular surfactants through sol-gel process. The unique characteristic such as large adjustable pore size, high surface area, uniform pore arrangement, and narrow pore size distribution have made such materials are widely used in many fields of advanced technology, such as photonic crystals, catalyst supports, adsorption. But in the application, the morphology of mesoporous materials and the inner structure has specific requirement, so the morphology control has been the focus of research. At present, a variety of morphology have been synthesized out, such as, threadiness, rodlike, hollow, sphericity and so on. The spherical particles have their particularity, so the preparation of spherical particles is still the focus for researcher.In this paper, the synthesis of sphericity mesoporous material has been studied:The ordered mesoporous silica was synthesized by using poly tri-block copolymers as templating and tetraethoxy silane as silicon source under a strong acidic condition. The influence factors include temperature, acidity, reaction time and stirring rate and so on. The main results are as follows:Within a limited range, the rise of temperature, the particle size decrease. The acidity influence the morphology and the size of SiO2, when the concentration of acid is lower, the rate of hydrolysis of TEOS is slower. At the same time the midterm products began to condense, the particle size is bigger. Increasing concentration of acid, enhance the interaction of templating and silicon, and resulting particle littler. The reaction time and mechanical agitation can affect the morphology and the size of particles. The use of inorganic salts can affect the morphology and size of particles theoretically. However, there is not any sphere particle information when KF is added in my experiment. It is probable due to inorganic salt damaged the formation of mesoporous phase.On the basis of basic theory research, try to synthetize the sphericity of SiO2 material using a double surfactant system, it turned out that:the particle size reduce, because F127 cover the micelle suppression the developing.