FUEL ADDITIVE CONTAINING CERIUM DIOXIDE NANOPARTICLES WITH ALTERED STRUCTURE Russian patent published in 2013 - IPC B01J23/10 B01J23/00 B82B1/00 B82B3/00 B01D53/94 F01N3/00 C10L1/12 C01F17/00 

FIELD: chemistry.

SUBSTANCE: invention relates to a method of producing cerium dioxide nanoparticles and use thereof. Described is a method of producing cerium dioxide nanoparticles with a given lattice, which contain at least one transition metal (M), wherein: (a) an aqueous reaction mixture is prepared, said mixture containing a source of Ce³⁺ ions, a source of ions of one or more transition metals (M), a source of hydroxide ions, at least one nanoparticle stabiliser and an oxidant which oxidises the Ce³⁺ ion to a Ce⁴⁺ ion, at initial temperature ranging from about 20°C to about 95°C; (b) mechanical shearing of said mixture and passing said mixture through a perforated sieve to form a homogeneously distributed suspension of cerium hydroxide nanoparticles; and (c) creating temperature conditions that are effective for oxidation of the Ce³⁺ ion to a Ce⁴⁺ ion to form a product stream containing cerium dioxide nanoparticles, containing a transition metal Ce_1-xM_xO₂, where x assumes a value from about 0.3 to about 0.8, said nanoparticles have a cubic fluorite structure, average hydrodynamic diameter ranging from about 1 nm to about 10 nm and geometric diameter from about 1 nm to about 4 nm, wherein the nanoparticle stabiliser is water-soluble and has a value Log K_BC ranging from 1 to 14, where K_BC denotes a constant for binding the nanoparticle stabiliser to a cerium ion in water and said temperature conditions that are effective for oxidation of the Ce³⁺ ion to a Ce⁴⁺ ion include temperature from about 50°C to about 100°C. Described is a method of preparing a homogeneous dispersion containing stabilised crystalline nanoparticles of cerium dioxide with a given lattice, containing a transition metal, Ce_1-xM_xO₂, where M is at least one transition metal and x assumes a value from about 0.3 to about 0.8; (a) preparing an aqueous mixture which contains stabilised cerium dioxide nanoparticles containing a transition metal, Ce_1-xM_xO₂, having a cubic fluorite structure, wherein, wherein said nanoparticles have average hydrodynamic diameter ranging from about 1 nm to about 10 nm and geometric diameter less than about 4 nm; (b) concentrating said aqueous mixture containing said stabilised cerium dioxide nanoparticles containing a transition metal, thereby forming an aqueous concentrate; (c) removing essentially all water from said aqueous concentrate to form an essentially water-free concentrate of stabilised cerium dioxide nanoparticles containing a transition metal; (d) adding an organic diluent to said essentially water-free concentrate to form an organic concentrate of said stabilised cerium dioxide nanoparticles containing a transition metal; and (e) merging said organic concentrate with a surfactant in the presence of a nonpolar medium to form said homogeneous dispersion containing stabilised crystalline nanoparticles of cerium dioxide containing a transition metal, Ce_1-xM_xO₂, where M and x assume values given above. Described is a deposited coating for the catalytic converter of the exhaust system of an internal combustion engine, where said deposited coating is obtained using said homogeneous dispersion.

EFFECT: catalyst that is efficient for a reduction or oxidation reaction is described, where said catalyst is obtained using said homogeneous dispersion.

44 cl, 9 dwg, 2 tbl, 8 ex