Preparing ultrafine barium sulfate particles using membrane-dispersion-precipitation technology

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.