Rare transition-metal catalyst for catalytic purification of CO, Nox and HC

Abstract

The invention discloses a rare transition-metal catalyst for the catalytic purification of CO, Nox and HC. The prior art has the disadvantages that the carrier function of noble metals and gamma-alumina is utilized for the catalytic purification of harmful substances in exhaust gas, which can lead to the result that under high temperature gamma-alumina carrier can be converted into alpha-alumina to present the state of intoxication; and the noble metals, such as palladium, platina, rhodium, and the like are used as catalyst, which can cause excessively high cost. The invention provides a rare transition-metal catalyst solving the disadvantages of the existing catalytic purification agent that aluminum oxide is easy to lose effectiveness under high temperature and the noble metals are needed. The catalyst has the oxygen storage function, the antitoxic function, the structure stabilization function, high activity, good thermal stability, ageing resistance and long service life, especially has the characteristic of lead poisoning resistance, increases the coated weight in a certain range, and the effect of catalytic purification thereof can be enhanced along with the increase of coated weight. The handling capacity of catalysis and purification of the catalyst is more than 90 percent, and especially the processing and purification of CO can reach 100 percent.

Description

technical field [0001] The invention relates to a rare transition metal catalyst for catalytic purification of CO, NOx and HC, and belongs to the technical fields of catalytic purification of engine tail gas and industrial organic volatile waste gas. Background technique [0002] Catalytic purification of engine exhaust is the process of converting harmful substances in exhaust gas into harmless substances and then discharging them. The main harmful substances in exhaust gas are exhaust gas particles, sulfides, carbon monoxide, hydrocarbons, and nitrogen oxides. At present, The substances that have a good catalytic and purification effect on these compounds are noble metals such as palladium, platinum, and rhodium. Using these noble metals and γ-alumina as carriers, the harmful substances in the exhaust gas are catalytically purified, but there are two problems in this way. One is that the γ-alumina carrier will transform into α-alumina at high temperature and present a pois...

AI Technical Summary

Problems solved by technology

[0002] Catalytic purification of engine exhaust is the process of converting harmful substances in exhaust gas into harmless substances and then discharging them. The main harmful substances in exhaust gas are exhaust gas particles, sulfides, carbon monoxide, hydrocarbons, and nitrogen oxides. At present, The substances that have a good catalytic and purification effect on these compounds are noble metals such as palladium, platinum, and rhodium. Using these noble metals and γ-alumina as carriers, the harmful substances in the exhaust gas are catalytically purified, but there are two problems in this way. One is that the γ-alumina carrier will transform into α-alumina at high temperature and present a poisoned state; the other is that palladium, platinum, rhodium and other precious metals are used as catalysts, which are too expensive

It has been found through research that when alumina is above 700°C, γ-alumina will be transformed and its activity will be lost.