Low loading palladium platinum core-shell structure catalyst and its preparation method and application

Abstract

The invention provides a low-load palladium-platinum core-shell structure catalyst. The catalyst is prepared through the following method that a Pd precursor and propylene carbonate are mixed, stirring for reacting is carried out for 1 h to 5 h in the hydrogen atmosphere of 1 MPa to 4 MPa under the room temperature condition, and a solution containing Pd nano particles is obtained; a Pt precursor is added into the obtained solution containing the Pd nano particles, stirring for reacting is carried out for 1 h to 5 h in the hydrogen atmosphere of 1 MPa to 4 MPa under the room temperature condition, and a solution containing core-shell structure active components is obtained; the obtained solution containing the core-shell structure active components and a carrier Al2O3 are mixed, stirring is carried out for 4 h to 48 h, suction filtration is carried out, a filter cake is subjected to vacuum drying, and a finished product is obtained. According to the synthesis method of the catalyst, raw materials are easy to obtain and can be reused, waste gas and waste water are not generated, the environmental cost is low, scaling up can be easily carried out for industrial production, the activity of the prepared catalyst is higher than that of a catalyst obtained according to an existing method, stability is good, and the catalyst can be applied to a methylbenzene catalytic oxidation reaction.

Description

(1) Technical field [0001] The invention belongs to the technical field of catalysts, in particular to a palladium-platinum core-shell structure catalyst (Pd@Pt / Al 2 o 3 type core-shell structure catalyst) and its preparation method, and its application in catalytic oxidation of toluene. (2) Background technology [0002] Volatile organic compounds (VOCs) are a class of major air pollutants and one of the main sources of PM2.5, which pose serious hazards to human health and ecology. In the newly promulgated "Code for Control of Indoor Environmental Pollution in Civil Buildings", the content of total volatile organic compounds (TVOC) in indoor air has become an important item to evaluate whether the indoor air quality of a room is qualified. The TVOC content specified in this standard is: Class I civil construction projects: 0.5mg / m3, Class II civil construction projects: 0.6mg / m3. Since interior decoration materials such as paints, adhesives, wallpapers and daily chemical...

AI Technical Summary

Problems solved by technology

These different types of structural designs have their own advantages and disadvantages, but the biggest problem is: firstly, the metal loading is relatively high, and the technology needs to be improved in order to reduce the preparation cost; secondly, most of the current domestic patents use single metal or platinum It can catalyze the complete oxidation of toluene with other metals as active components, and the two metals, palladium and platinum, actually have a good synergistic effect on the catalytic oxidation of toluene; finally, in the loading process of the two metals, the operation is more cumbersome, and A large amount of waste water and waste gas will also be generated during the synthesis process, which violates the principles of green chemistry

However, there is only Pt in the supported metal and the complete oxidation temperature is high, so the synergistic effect between metals has not been explored.

Images