ISSN print edition: 0366-6352 ISSN electronic edition: 1336-9075 Registr. No.: MK SR 9/7 Published monthly

Precipitation of Mg(OH)₂ by the Reaction of Mg(N0₃)₂ with Ammonia in a Flow Reactor

M. Láska, V. Khandl, and P. Fellner

Department of Inorganic Technology, Faculty of Chemical Technology, Slovak Technical University, SK-812 37 Bratislava

Abstract: The influence of ammonia content and of the retention time on the crystal size distribution of magnesium hydroxide prepared by the precipitation from Mg(NO₃)₂ solutions in a flow reactor was investigated. The temperature of the reacting mixture was 80°C. It was found that the higher is the content of ammonia and/or its surplus with respect to the stoichiometric demand, the larger are the Mg(OH)₂ crystals. The longer is the retention time, the lower is the fraction of the particles smaller than 24 μm in the product. When the retention time of Mg(OH)₂ in the reactor is shorter than 3 min, irregular agglomerates of Mg(OH)₂ with sharp edges are formed while at the retention time longer than 5 min the aggregates have a round shape.

Full paper in Portable Document Format: 485a313.pdf

Chemical Papers 48 (5) 313–316 (1994)