Multifunctional catalyst, and preparation method and application thereof

Abstract

The invention discloses a multifunctional catalyst, and a preparation method and application thereof. A mixture of zirconium hydrogen phosphate and titanium trioxide is taken as a carrier, a cerium-manganese-iron composite oxide is taken as a catalytic active component, and strontium oxide is taken as a cocatalyst. Based on the mass of the carrier, the mass percentage of the active component is 2-4%, and the mass percentage of the cocatalyst is 0.5-1%. The preparation method comprises the following steps: uniformly stirring the active component, a cocatalyst precursor solution and the catalystcarrier, performing aging, and then carrying out extrusion molding, drying, and roasting. The catalyst is environmentally friendly, can remove NOx in diesel engine tail gas and synergistically catalyze and remove CO and HC at a low temperature, and has a wide active temperature interval and low SO2 oxidation efficiency. The denitration efficiency of the catalyst is higher than 95% and reaches upto 100% in a temperature range of 150-350 DEG C, and the oxidation efficiency of CO and HC is higher than 90% and reaches up to 98.7% and 97.6%, respectively. The catalyst is high in cost performanceand particularly applicable to the field of low-speed diesel engine tail gas purification.

Description

technical field [0001] The invention relates to a multifunctional catalyst and its preparation method and application, belonging to the fields of environmental protection catalytic materials and air pollution control, and the product prepared by the method is especially suitable for the field of low-speed diesel engine tail gas purification. Background technique [0002] With the development of my country's economy and society, the problem of air pollution has become increasingly prominent. Among them, the pollution caused by motor vehicle exhaust emissions occupies a considerable proportion, while the emissions of diesel vehicles, especially heavy-duty diesel vehicles, are significant. Because of its high efficiency and good stability, the ammonia selective catalytic reduction method has been recognized as the mainstream technical route for denitrification of diesel vehicle exhaust. Selective catalytic reduction (SCR) has become the mainstream technology and development di...

AI Technical Summary

Problems solved by technology

Although the above-mentioned catalysts can solve the problem of strong strength of the catalytic coating, they cannot solve the problem of poor hydrothermal stability of molecular sieves.