METHOD OF PRODUCING PHOTOCATALYST BASED ON BISMUTHATE ALKALI-EARTH METAL AND METHOD OF PURIFYING WATER FROM ORGANIC CONTAMINANTS USING PHOTOCATALYST

摘要

FIELD: chemistry.;SUBSTANCE: invention relates to a method of producing a photocatalyst based on bismuthate of an alkali-earth metal and to a method for photocatalytic treatment of water from organic contaminants. Method of producing a photocatalyst involves dissolving bismuth nitrate and alkali-earth metal nitrate in a solvent, wherein solvent is an aqueous solution of polyatomic alcohol, containing at least five carbon atoms, with subsequent annealing of precursor at 550-650 °C to produce nanoparticles of amorphous bismuthate of alkali-earth metal of non-stoichiometric composition with degree of oxidation not equal to two. Prior to annealing, precursor is evaporated until formation of an organic matrix with uniform distribution of bismuth and alkali-earth metal atoms. Then a crystal lattice of photocatalyst is formed at 650-750 °C. When purifying water from organic contaminants using photocatalyst, weight ratio of purified water to weight of photocatalyst is selected from interval of 1000/1-1600/1, and irradiation with visible light of water with organic pollutants is carried out for 3-4 hours.;EFFECT: method enables to obtain particles of bismuthate of alkali-earth metal with an inhomogeneous composition, in form of a heterostructure of bismuth oxide, coated with bismuthate of alkali-earth metal of stoichiometric composition with degree of oxidation of calcium, equal to two, without defects in crystal lattice with low specific surface area without pores, as well as reduced consumption of photocatalyst during water treatment due to reduction of average particle size of photocatalyst and broader functional capabilities.;4 cl, 2 tbl, 59 ex