Effects of operating parameters on the production of barium sulfate nanoparticles in stirred media mill

A systematic study on wet grinding of barium sulfate to produce nanoparticles (<50 nm) was performed in a stirred media mill. The suspension stabilization by pH adjustment and dispersants addition were investigated using zeta potential measurement and the multiple light scattering methods. It was found that particle size reduction requires use of dispersant (sodium salt of polyacrylic acid). The optimum amount of dispersant concentration was determined to be 2% by weight. Further, the influence of pin-length was found to improve the performance. The influence of solids mass fraction, grinding media diameter on pH variation and final size were evaluated.