Catalyst for complete oxidation of formaldehyde at room temperature

Abstract

The invention provides a high selectivity catalyst used for catalyzing and completely oxidizing formaldehyde with low concentration at room temperature. The catalyst can catalyze formaldehyde completely so as to lead the formaldehyde to be converted into carbon dioxide and water at room temperature. In addition, the conversion rate of formaldehyde remains 100% within a long period of time, without complex auxiliary facilities such as light source, a heating oven and the like, and external conditions. The catalyst comprises three parts which are inorganic oxide carrier, noble metal component and auxiliary ingredient. Porous inorganic oxide carrier is one of cerium dioxide, zirconium dioxide, titanium dioxide, aluminium sesquioxide, tin dioxide, silicon dioxide, lanthanum sesquioxide, magnesium oxide and zinc oxide or the mixture thereof or composite oxide thereof, zeolite, sepiolite and porous carbon materials. The noble metal component of the catalyst is at least one of platinum, rhodium, palladium, gold and silver. The auxiliary ingredient is at least one of the alkali metals of lithium, sodium, kalium, rubidium and cesium. The loading of the noble metal component used in the catalyst of the invention is 0.1 to 10% according to weight converter of metal elements and the selective preference is 0.3 to 2%. The loading of the auxiliary ingredient is 0.2 to 30% according to weight converter of metal elements and the selective preference is 1 to 10%. When the loading of the auxiliary ingredient is lower than 0.2% or higher than 30%, the activity of the catalyst for catalyzing and oxidizing formaldehyde at room temperature is decreased remarkably.

Description

technical field [0001] The present invention relates to a catalyst, in particular to a catalyst for purifying formaldehyde, the main pollutant in indoor air. The catalyst involved in the present invention has excellent activity in catalytic oxidation of formaldehyde, and can catalytically oxidize formaldehyde gas into carbon dioxide at room temperature and water. technical background [0002] With the improvement of people's material and cultural living standards, interior decoration has become fashionable, but indoor air pollution is also becoming more and more serious. Formaldehyde is one of the most typical and serious pollutants in the indoor environment. The concentration limit of formaldehyde pollutants in indoor air stipulated by my country's national standards is 0.08mg / m 3 . At present, the concentration of formaldehyde in the indoor environment of our country exceeds the standard. According to the sampling survey conducted by the National Center for Disease Cont...

AI Technical Summary

Problems solved by technology

[0003] At present, commonly used indoor air purifiers mainly use the strong adsorption of adsorbent materials to adsorb pollutants such as formaldehyde. Porous clay ore, activated alumina and silica gel, etc. This method is relatively simple to operate, but the adsorbent needs to be replaced regularly, which is prone to secondary pollution

Plasma catalytic technology can decompose indoor harmful gases at normal temperature and pressure, but by-products such as carbon monoxide, ozone and nitrogen oxides will be produced, and the plasma generation equipment is expensive

The technology of photocatalytic decomposition of pollutants is currently the most researched indoor air purification technology, and has achieved good indoor air purification effects, such as the nano-solid super-acid photocatalyst that has obtained the national invention patent (patent number ZL98115808.0), but this Nano-catalysts mainly use TiO2 nano-powders or thin films as photocatalysts. The raw material preparation methods are complicated and the technical requirements are high, and nano-photocatalysts require specific excitation light sources.

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