Diesel vehicle oxidized form catalyst having low temperature activity and preparation method thereof

Abstract

The invention relates to a diesel vehicle oxidized form catalyst having low temperature activity and a preparation method thereof.The catalyst comprises a carrier and a coating applied to the carrier, the coating is loaded with noble metal, the coating comprises tungsten-aluminum silicon composite oxide and molecular sieves, the noble metal is one of Pt and Pd or a mixture of the two types of substances, the coated weight of the coating is 80-180 grams/liter, and the coated weight of the noble metal is 0.5-4.5 grams/liter.The preparation method comprises the steps of firstly, preparing the tungsten-aluminum silicon composite oxide through an equivalent-volume impregnation method, then making slurry with the molecular sieves and the tungsten-aluminum silicon composite oxide according to the mass ratio of 1: (2-10), adding the noble metal Pt and Pd, finally immersing the carrier into the slurry, and conducting drying and sintering, so that the diesel vehicle oxidized form catalyst is obtained.The preparation method of the catalyst is simple, the steps are easy to operate, the prepared diesel vehicle oxidized form catalyst is low in combustion temperature, high in conversion rate and good in thermal stability, good capability for oxidizing HC and CO in tail gas of a diesel vehicle is achieved, and good sulfur resistance is achieved.

Description

technical field [0001] The invention relates to a diesel vehicle oxidation catalyst with low-temperature activity and a preparation method thereof, belonging to the technical field of catalyst preparation. Background technique [0002] With the rapid development of the economy and the continuous improvement of people's living standards, the transportation industry has achieved unprecedented development, and the output and number of motor vehicles have increased year by year. When fuel cell vehicles and hybrid vehicles are not yet popularized, diesel vehicles have higher fuel economy and relatively lower exhaust pollution compared with gasoline vehicles. The market demand in the 21st century is growing rapidly. With the continuous increase of the number of diesel vehicles, the atmospheric environmental pollution caused by diesel vehicle exhaust emissions has also attracted more and more widespread attention. The pollutants emitted by diesel vehicles are mainly carbon monoxid...

AI Technical Summary

Problems solved by technology

However, due to the high sulfur content in domestic oil products, the tail gas contains more sulfur dioxide (SO 2 ), and sulfur dioxide will be oxidized to sulfur trioxide (SO 3 ), further forming sulfate, causing catalyst deactivation and poisoning, reducing the catalyst’s ability to convert CO, HC and SOF in diesel vehicle exhaust, so DOC should have certain sulfur resistance properties