화학공학소재연구정보센터
KAGAKU KOGAKU RONBUNSHU, Vol.27, No.3, 303-313, 2001
Preparation and microscopic structure control of fine particle materials by using emulsion liquid membrane system as a microreactor
Fine particle materials were prepared by using an emulsion liquid membrane (ELM, water-in-oil in- water (W/O/W) emulsion) system. Metal ions were extracted from the external water phase into the organic membrane phase containing extractant (cation carrier), and then stripped into the internal water phase to make submicron-or micron-sized oxalate, carbonate and phosphate particles, of which the size, morphology and crystal structure were well-controlled. As case studies, the preparation of well defined spherical oxalate particles of rare earth metals, spherical calcium carbonate particles of hollow structure, spherical calcium phosphate particles, composite Sr-Pb oxalate particles, acicular Co ferrite and Ni ferrite fine particles, and rare earth oxide spherical phosphor particles was demonstrated, and the properties and functions of the internal water phase as a microreactor are discussed.