Using extraction and sorption processes to obtain nanosized powders of calcium silicates and functional materials on their basis

Resumo

The review presents summary data on extracting agents and the application of sorption processes during the cycle of studies on the joint processing of calcium and silicon-containing raw materials on the production of calcium silicates and composite materials on their basis. It is found that, in processes of the production of synthetic calcium silicates from various types of calcium and silicon-containing raw materials, ionic and nonionic surfactants, including extractants, serve as structuring additives that hinder crystal growth and impede their agglomeration. The sorption properties of amorphous and crystalline nanopowders of calcium silicates and hydrosilicates synthesized from water-soluble materials are studied with respect to cations of base and rare metals. It has been found that the studied samples have high sorption capacity for cations of Eu3+, Pr³⁺, Tb³⁺, Er³⁺ and may be used as the basis for producing functional composite materials. The efficiency of applying the extraction-pyrolytic method has been shown to provide homogeneity and predetermined composition of the desired products, for the production of ceramic pigments and luminescent materials based on calcium silicates.