Removal of formaldehyde

1. Ventilation method: Ventilation method does not have to explain too much, that is, through the flow of air, it discharges harmful gases to the outside. This is a simple and effective method. The only drawback is the long period of formaldehyde release, which generally takes three to fifteen years. It is obviously unrealistic for the new home to be idle for more than three years after the renovation. Trapped by the ventilation method alone can not meet the requirements.

2. Formaldehyde Scavengers or Formaldehyde Soluble Enzymes: Formaldehyde scavengers rely on chemical reactions to “remove” formaldehyde. The essence of this method is to reduce the toxicity of the target substances or convert them into non-toxic substances. Formaldehyde, which can be oxidized to formic acid, can also be reduced to methanol. Although the toxicity and irritation of these two substances are lower than that of formaldehyde, their toxicity still exists. For example, some strong oxidizing formaldehyde scavenger can oxidize formaldehyde, but it is easily decomposed by itself. Spraying on a wood board will damage the wood and it will not be effective within hours. It is impossible to achieve “one shot forever”. Moreover, the high concentration of scavenger sprayed in the air will cause people new pollution hazards. Other oxidants and reducing agents are also not effective in removing formaldehyde, and will introduce similar new pollution.

For some businesses propaganda, formaldehyde dissolved enzymes through the penetration into the plate, the principle of harmful gas removal, it is not credible, many plate production process are high humidity and high pressure, and often the surface is also skinned, formaldehyde removal How can agents penetrate into the interior?

3. Adsorption of activated carbon: The initial use of activated carbon does have an effect because pores have an adsorption potential and are formed by the attraction of carbon molecules and adsorbed molecules. The smaller the pore size, the stronger the adsorption potential. In addition, according to the theory of molecular motion, all objects are made up of molecules or atoms with gaps between them. At the same time, they are in a state of non-regular thermal movement. The collision between molecules is frequent. According to relevant data, in the standard state, the free movement speed of formaldehyde molecules is about 450 meters per second, and one molecule of formaldehyde collides with other molecules 109 times per second. At this point, the diameter of the collision molecule is adsorbed if it matches the pore of the activated carbon. Whether it is traditional activated carbon or modified activated carbon that is currently being smelted much more, its adsorption capacity is limited due to its large pore size.

4. Photocatalyst removes formaldehyde: The photocatalyst will produce a photocatalytic reaction similar to photosynthesis under the irradiation of light, producing free hydroxyl radical and active oxygen with strong oxidizing ability, having a strong photo-oxidation and reduction function, and oxidative decomposition. Various organic compounds and some inorganic substances can destroy the cell membrane of bacteria and the proteins that cure viruses, kill bacteria and decompose organic pollutants, and decompose organic pollutants into pollution-free water (H2O), carbon dioxide (CO2) and others. Non-hazardous material, thus has a strong bactericidal, deodorant, anti-mildew, anti-fouling self-cleaning, air purification function. In theory, photocatalyst is a kind of the highest quality addition to formaldehyde products, but in fact the photocatalyst must play a role, there must be ultraviolet light to stimulate, and the room can not always exist ultraviolet light, especially in some drawers, the back of the cabinet and other formaldehyde In the worst place to release, there is no light. This limits the role of photocatalysts.

5, plants absorb formaldehyde: plants can absorb some of the harmful substances through photosynthesis, but the role of such methods is very limited. Reasons: (1) The plants are engaged in photosynthesis and they usually inhale some harmful substances during the day and do not have this function at night. The law of human life is usually outdoors during the day and indoors at night. When people most need air purification, plants do not have a corresponding role. (2) The harmful substances absorbed by plants are extremely limited. National standards require formaldehyde emission values ​​of less than 0.08 mg/m3. For most houses that have just been renovated, formaldehyde is not less than 0.2 mg/m3, while formaldehyde, which absorbs formaldehyde with high efficiency, absorbs only formaldehyde per hour. It is 20 micrograms. Taking a room with 100 square meters, a room height of 3 meters, and a formaldehyde value of 0.2 milligrams per cubic meter, it requires 1800 pots of green radish at the same time. It almost fills up the entire space of the house to reduce formaldehyde to 0.08 milligrams. This is still during the day. It is carried out under sufficient light conditions and it is ensured that formaldehyde is no longer released during the absorption process. In fact, the formaldehyde in the renovated furniture has been continuously released. Therefore, plants can only play an auxiliary role in the control of harmful substances such as formaldehyde and benzene.

6, vinegar fumigation: vinegar is an acidic substance, there is a weak role in neutralizing the role of ammonia in the air, but it will not react with formaldehyde and other harmful components.

7, Maya blue in addition to formaldehyde: Maya blue is a rare earth as a raw material adsorbent, rare earth has "industrial vitamin" reputation. It is a strategic material of our country. It has strictly restricted exports and is a necessary raw material for producing various high-tech products. In developed countries, the purification and adsorption capacity of rare earths has been applied many years ago, but our country has only begun to use them in recent years. Maya Blue is one of the typical representatives. Maya Blue is made of rare earth raw materials through high-temperature purification, ultrasonic dispersion and other processes, with a unique microscopic crystal structure, natural nano-scale lattice gap, high specific surface area (large number of pores), high permeability, and pore surface with Polarity and other characteristics, the pore size of its internal pores between 0.27-0.98 nm, crystal arrangement. At the same time, it has weak electricity, and the molecular diameters of formaldehyde, ammonia, benzene, toluene, and xylene are all between 0.4 and 0.62 nanometers, and they are all polar molecules. Therefore, they have the characteristics of preferentially adsorbing harmful gases such as formaldehyde, benzene, and TVOC, and are The effect of purifying indoor air, but its pure natural characteristics will not cause secondary pollution. However, due to the high price of raw materials, it has limited its widespread use.