Edta Network For Preparation Of Nano Barium Sulfate Process

Barium sulfate particles with 1~100nm in size, compared with general barium sulfate, show outstanding properties in chemistry and physics. It is expected to be applied in especial paint and ceramic industry. Several methods for preparing nano barium sulfate are dicussed in this paper. On the base of complexion reaction mechanism, new complexion method is originated.The multiphase heat transfer and mass transfer in the process of crystals are analysed based on the theory of both crystals and complexion reactions. The mathematical model of both forming nucleus and their growth is discussed. According to homogeneous reaction precipitation and complexion reaction, the key operation parameters related to properties of nano particles are determined. The effects of these parameters, such as concentration of raw materials, pH of precipitation solution, pH of complexion process, reaction temperature and different method of desiccation on particle distribution in size and crystal type as well as its purification are experimentally researched. These methods of TEM , BET, XRD are used to test the properties of nano barium sulfate . And this processing method involves choice of primary equipments and fixing parameter in purification and desiccation of nano-scale production. An optimum technology is obtained based on the series of experimental data. As a result, the average particle diameter is 25nm, particle distribution in size is between 20nm and 40nm.In a word, this technology for preparing nano barium sulfate revealsthe mechanism of complexion reaction and innate character of precipitation reaction. What is more, the mechanism and essence of nucleating (precipitation) in this reaction have primarily been opened out so that there are a little new methods in studying and thinking of preparing ultrafine through nucleating in some reactions.