32results about How to "High oxygen storage" patented technology

The invention discloses a ternary-cerium-based oxygen storage material and a preparation method thereof. The oxygen storage material consists of an oxygen storage material main body, aids, and a dispersing agent; the oxygen storage material main body is a rare earth material which consists of cerous nitrate, zirconium nitrate and lanthanum nitrate; the aids are barium nitrate, copper nitrate, manganous nitrate or magnesium nitrate; the dispersing agent is polyvinyl alcohol, polyethylene glycol or citric acid; and the material has the advantage of obviously reducing the ignition temperature oftail gas catalytic conversion of a three-way catalytic converter, prolonging the service life of the three-way catalytic converter, and greatly reducing the fluctuation of air-fuel ratio windows during working of the three-way catalytic converter. Compared with the three-way catalytic converter in which the oxygen storage material is not adopted, the three-way catalytic converter in which the oxygen storage material is adopted has the advantage that the using amount of noble metal can be reduced by over 17 percent.

The present invention provides a cerium-zirconium composite oxide, comprising cerium oxide, zirconium oxide and at least one oxide of rare earth metal elements other than cerium. The pore size of the double pore group distribution, wherein the diameter of the first pore group is concentrated in 2-10 nm, and the diameter of the second pore group is concentrated in 15-80 nm. The cerium-zirconium composite oxide provided by the invention has remarkable low-temperature catalytic activity, and can be used to catalyze hydrocarbons, carbon oxides and / or nitrogen oxides in the exhaust gas of the mobile source. The invention also provides a preparation method of cerium-zirconium composite oxide, which can prepare and obtain cerium-zirconium composite oxide with more uniform element lattice doping distribution and no phase separation, and can treat and purify mobile source exhaust gas containing cerium-zirconium composite oxide The study of the drug is of great significance.

The invention discloses a preparation method for a palladium-doped cerium-zirconium composite oxide. The preparation method includes the following steps: cerium acetate and zirconium acetate are dissolved in deionized water, and a first mixed solution is obtained after uniform mixing; OP-10, P123 and n-butyl alcohol are respectively dripped into a solvent (methylbenzene), the mass ratio of the OP-10, the P123 and the n-butyl alcohol is 5-6 to 2-3 to 10-15, and a second mixed solution II is obtained after uniform mixing; the first mixed solution and the second mixed solution are mixed and stirred at a high speed to obtain a mixed emulsion; 2 weight percent palladium acetate is dripped in the mixed emulsion, and the mixture is stirred uniformly; 20 weight percent ammonium hydroxide is prepared to serve as a precipitator; the mixed emulsion and the precipitator (the 20 weight percent ammonium hydroxide) are then mixed, the mixture is stirred at a high speed for 2 to 3 hours and then stands for 12 to 24 hours within a temperature range of 40 to 50 DEG C, and a dirty solution is obtained; the dirty solution goes through high-speed centrifugal separation and suction filtration, and obtained solid phase matters are dried within a temperature range of 100 to 120 DEG C and calcined within a temperature range of 400 to 500 DEG C to obtain the palladium-doped nanometer cerium-zirconium composite oxide. The palladium-doped cerium-zirconium composite oxide prepared through the method has the characteristics of small particle diameter (the diameter can reach the nanometer level), large specific surface area and oxygen storage capacity, high oxygen storage and discharge rates, and high sintering resistance.

The invention discloses a cubic phase cerium-zirconium-based composite oxide with high specific surface area. Rare earth elements are doped into the cerium-zirconium composite oxide, and the rare earth elements are two or three of Pr, Nd and La, wherein The molar ratio of Zr to Ce is 1.8~2.5:1, the molar ratio of Pr to Ce is 0~0.32:1, the molar ratio of Nd to Ce is 0~0.32:1, and the molar ratio of La to Ce is 0~0.16: 1. The cerium-zirconium-based composite oxide exists in the form of cerium-zirconium solid solution. The invention also discloses its preparation method. The present invention prepares composite oxides through different precursor precipitation and drying methods. The reaction process is simple and the requirements for drying equipment are low. The obtained cerium-zirconium-based composite oxides have high specific surface area, high thermal stability and high oxygen storage and release capacity. After 1000 After calcination at ℃ for 12 hours, the specific surface area is higher than 35m2 / g, more particularly higher than 60m2 / g.

The invention discloses a preparing method for rare earth compounds and belongs to the technical field of preparation of inorganic composite materials. The method comprises the steps that Ce, Zr, La, Pr, Nd, Yb and other compounds are selected as precursors, and a ternary rare earth compound, a quaternary rare earth compound and a polynary rare earth compound are prepared respectively; powdery porous activated carbon is arranged in corresponding precursor solutions, then stirring is carried out, a precipitator is added after adsorption is conducted for a certain time to precipitate the mixture, the pH value is adjusted to be proper, aging is conducted after complete precipitation, and the mixture is filtered, washed, dried and them roasted at a high temperature. The rare earth compounds prepared through the method have the advantages of being large in specific surface area, high in OSC and the like; TEM representation shows that the compounds are nanoparticles with the particle size ranging from 9 nm to 20 nm. The compounds prepared through the method can be widely applied to the fields of petroleum, chemical industry, environmental protection and the like.