Study On The Preparation Of Micron Barium Sulfate

As an important kind of inorganic product, the barium sulfate has many advantages, such as low cost on the development, low hardness and oil absorption values, avirulence, light color, high brightness, anti-acid and anti-alkali, lightfastness and well dispersed. It has become a kind of irreplaceable inorganic filler material. Normal micro-processed barium sulfate particles (particle size: 0.1μm ~ 1.0μm) have shown better application effects and high economic value in plastic, dope, paints, ceramics, paper, and many other related fields. China is rich in barite (a kind of natural compounds containing barium sulfate), and its reserves, outputs and exports rank first in the world. However, more than 95% exports of barite of China are low-level, low added value, low utilization of the ore and primary products. At the same time, the domestic demand for high quality barium sulfate powders are needed with high-priced imports. Therefore, preparation of high-quality barium sulfate powder is the prime choice of conservation of barite mineral resources and enhancement of business competitiveness.As the nano-scale barium sulfate particles are small, the dispersion is poor, so the application subjects to certain restrictions. Therefore, micro-level barium sulfate particles attract more and more attention of people. In this paper, the submicron-barium sulfate was prepared by micro-reactor technology combined with the traditional precipitation method. Barium sulfate emulsion, as seeds, was prepared by micro-reactor technology using BaS and Na2SO4 as reactant. The BaSO4 crystal seeds were prepared, whose particle size is 90 nm, and relation between the operation conditions (content ratio, temperature and flow rate) and barium sulfate particle size were studied. In combination with the traditional precipitation method, the effects of temperature, amount of seeds, reactant, and time on the particle size of micrometer-barium sulfate was analyzed. The morphology and particle size of barium sulfate were characterized by the scanning electron microscopy and laser particle size distribution instrument. The results showed that particle size of barium sulfate were about 0.3μm ~ 0.5μm with narrow distribution, and the optimum conditions were as follows: reactant concentration was 0.5 mol /L, seeds were 4.0 mL, and reaction time was 1 h at room temperature. The morphology of BaSO4 particle is sphere.