... substances, such as formaldehyde, benzene, ammonia, sulfur dioxide, carbon monoxide, nitric oxides that affect the human body in the air ... .3. Deodorization: it can remove odours giving out from smoke, bathroom, rubbish and animal, and so on4. Anti-pollution ... air-conditioning, air-conditioning fan, air purification machine and smoke exhaust ventilator, and so sonThe photocatalyst is classified by: ...