DESIGN OF A NEW MIXING DEVICE FOR PRECIPITATION PROCESSES

摘要

The precipitation of pseudo-boehmite is studied using the Rotating Disk Reactor (new mixing device designed to produce particles with controlled properties) and a second reactor, namely the Special Rushton Turbine Reactor, which is a jets precipitator with feeding of the reagents by the bottom. Influence of feed point location, reactant concentration, water dilution, micromixing time at the reagent feed point and residence time on product quality is investigated in order to compare particle properties obtained by different reactor technologies. Product quality properties evaluated are Particle Size Distribution, crystallite size, BET surface area, porous volume and particle shape. Special attention is paid to the influence of the mixing phenomena and the type of flow at the reagent feed point locations.