Industrial process for preparing nm-class active calcium carbonate

Abstract

The invention provides the industrial preparation method of the nano activated calcium carbonate. The crystal control agent is added in the suspending liquid of the calcium hydroxide and is carbonized by the kiln gas containing the carbon dioxide. Through controlling the temperature and concentration of the calcium hydroxide, the concentration of the carbon dioxide and the addition and variety of the crystal control agent, the initial nucleation rate and nucleation quantity of the crystal and the growth rate of each crystal face of the crystal during carbonization are adjusted to realize the shape control of the crystal, and then surfactant is added to conduct activating treatment. The nano activated calcium carbonate is gained after filtering and drying, which has a shape of cube and is regulable when the grain size is between 20nm to 100nm. The product gained by the method has excellent performance and can work as the functional filler, which can be widely used in such industries as top-grade coating, rubber, plastic and adhesive.

Description

technical field

[0001] The invention relates to an industrial preparation method of calcium carbonate, in particular to an industrial preparation method of nano-active calcium carbonate. technical background

[0002] Nano-calcium carbonate refers to calcium carbonate powder with a particle size of less than 100nm. The surface of calcium carbonate is hydrophilic under normal conditions, and becomes lipophilic after surface organic treatment, becoming nano-active calcium carbonate. It is widely used in plastics, rubber, and polymer resins to improve product performance and product quality. It is a new type of functional inorganic filler.

[0003] At present, the preparation methods of nano-calcium carbonate include continuous spray method, high gravity carbonization method, and stirring tank carbonization method. The nozzles of the continuous spray method are easy to block, and it is difficult to ensure the consistency of the droplets in industrial production, which requires ...