Preparation method and application of a noble metal monolithic catalyst for formaldehyde purification

Abstract

The invention discloses a preparation method and an application of a noble metal monolithic catalyst for purifying formaldehyde. With adopting of a homogeneous deposition composite in-situ reduction method, firstly a platinum and palladium precursor is uniformly deposited on a flaky and regular activated carbon fibrofelt through an equivalent saturated impregnation method, then sodium borohydride is used as a reducing agent and is directly subjected to an oxidation-reduction reaction with the noble metal precursor on the surface of the activated carbon fibrofelt, and noble metal metallic-state microcrystals are formed in-situ; the noble metal content in the monolithic catalyst prepared by the preparation method is 0.5-3.0 wt%; when the monolithic catalyst is applied in formaldehyde catalytic oxidation purification treatment, under conditions of the initial formaldehyde concentration of 1-5 mg / m<3> and the air speed of 180000 mL / gcat.h, the formaldehyde room-temperature purification rate is 89% or more, so the monolithic catalyst is an excellent monolithic type catalyst for room temperature purification treatment of low-concentration formaldehyde, and is suitable for deep purification treatment of formaldehyde harmful gas in industries and living rooms.

Description

technical field [0001] The invention relates to a preparation method of a noble metal integral catalyst for formaldehyde purification, and the catalyst is used for deep purification treatment of formaldehyde at room temperature. Background technique [0002] Formaldehyde is a colorless gas with a strong pungent smell. It can combine with proteins in the human body through the digestive tract, respiratory tract, skin contact and eye contact, causing severe irritation and edema of the respiratory tract, causing respiratory inflammation and lung inflammation. Functional damage, even causing human nervous system disorders and lymphocyte damage, resulting in malignant tumors, etc., has become one of the important environmental pollutants. However, formaldehyde exists in a large amount in the adhesives and coatings used in interior decoration materials and wooden furniture, and the formaldehyde in these materials will continue to release for more than two years at room temperature...

AI Technical Summary

Problems solved by technology

However, due to the low adsorption strength and adsorption capacity of activated carbon fiber felt to formaldehyde, the efficiency of removing formaldehyde during use is low, and it will fail when it reaches adsorption saturation, and it cannot be used continuously for a long time; When it rises, it is easy to desorb and release formaldehyde, causing secondary pollution

Catalytic oxidation method is one of the commonly used methods to deal with industrial VOCs. Most of them use cordierite honeycomb ceramic supported noble metal-based monolithic catalysts, which can quickly oxidize VOCs into carbon dioxide and water at lower temperatures. This method is also currently used in In the low-temperature purification treatment of formaldehyde, but the catalytic oxidation method has the problems of low purification efficiency and high purification temperature (above about 100°C) when dealing with low-concentration formaldehyde

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