METHOD OF DOPING TITANIUM DIOXIDE WITH ANATASE ALLOTROPIC MODIFICATION WITH NOBLE METAL NANOPARTICLES (EMBODIMENTS) Russian patent published in 2020 - IPC C01G23/53 B01J21/06 B01J23/50 B01J23/52 B01J35/00 B01J37/08 B01J37/16 B01J37/34 C02F1/32 C02F1/72 B01D53/86 B82B3/00 B82Y30/00 B82Y40/00 

FIELD: chemistry.

SUBSTANCE: group of inventions relates to chemistry and specifically to technology of doping titanium dioxide with anatase allotropic modification with noble metal nanoparticles to create a highly efficient photocatalyst for photocatalytic oxidation reactions of organic compounds in mild conditions. In the first embodiment, the method involves preparation of an aqueous solution of a chitosan salt form, into which a precursor - corresponding salts of gold or silver is added. Thereafter, the system is intensely mixed and subjected to UV exposure to form noble metal nanoparticles at temperature of 20–70 °C. After achieving maximum intensity of plasmon resonance band of nanoparticles, titanium dioxide is introduced into system with continuous stirring of anatase allotropic modification. An enzyme is then added to the dispersion. Enzymatic decomposition of chitosan macromolecules is carried out at temperature of 35–40 °C to complete degradation of chitosan. In the second embodiment, titanium dioxide is dispersed in anatase allotropic modification in an aqueous solution of chitosan salt form with intense stirring. A precursor corresponding to gold or silver salts is then added to the dispersion. System is stirred and exposed to UV exposure to form noble metal nanoparticles at temperature of 20–70 °C. Formation of metal nanoparticles is monitored spectrophotometrically. After maximum intensity of plasmon resonance band of nanoparticles is reached enzyme is introduced into the system. Enzymatic decomposition of chitosan macromolecules is carried out at temperature of 35–40 °C to complete degradation of chitosan.

EFFECT: technical result is process simplification with reduction of power inputs, increased efficiency and uniformity of distribution of noble metal nanoparticles on surface of titanium dioxide.

10 cl, 8 dwg, 2 tbl, 13 ex