【摘要】 将膜分散技术应用于超细颗粒的制备过程,以氯化钡和硫酸钠为原料制备硫酸钡为例,对于膜分散沉淀法制备超细硫酸钡颗粒的影响因素进行了研究,并将膜分散沉淀法与直接搅拌沉淀法相比较。研究结果表明:在同样的反应条件下,直接搅拌沉淀法得到的颗粒成片状,粒度在0.3～1.0 μm;而膜分散沉淀法得到的颗粒球形度好,平均粒径在10～100nm。膜分散沉淀法制备硫酸钡超细颗粒粒度小,粒径分布窄,单分散性好;硫酸钡颗粒粒度随硫酸钠浓度的升高而迅速降低。在膜分散沉淀过程中无需进行搅拌。该方法与直接沉淀法相比具有能耗低、可连续操作、以及粒径可控的优点,是一种高效新型的超细颗粒制备方法。更多还原

【Abstract】 This paper describes membrane-dispersion-precipitation technology for preparing ultrafine particles. The various factors affecting the preparation of barium sulfate nanoparticles were investigated. The particle size and morphology of particles prepared with the new method or with the direct precipitation method were characterized by scanning electron microscope and transmission electron microscope images. The results show that particles prepared using direct chemical precipitation from solutions of BaCl2 and Na2SO4 are in the range of 0.3 - 1.0μm. However, the new method with the same solution concentrations produced partriles in the range of 10-100nm. The particles prepared by membrane dispersion technology were spherical with a narrow size distribution. The particle size decreased quickly with increasing Na2SO4 concentrations. This method uses little energy and can be operated continuously.更多还原