Patent · US Expired

Photocatalytic air treatment process under room light

US5874701A · kind A · utility

55Cited by
3References
24Claims
0Family size

Assignee

Inventors

Key dates

Filing dateApr 10, 1996
Grant dateFeb 23, 1999
Priority date
Expiry dateApr 10, 2016

Classification

  • Technology area (CPC B)Performing Operations; Transporting
  • CPC primaryB01D2259/804
  • WIPO fieldChemical engineering
  • WIPO sectorChemistry

Abstract

A process for photocatalytically treating a hospital room contaminated by bacteria or an interior environment bearing airborne malodorous substances. A thin film of photocatalyst made of a semiconductor such as titanium dioxide is disposed on the inner wall of the hospital room or living space. The photocatalytic thin film is irradiated by a light source suitable for general lighting applications, such as a fluorescent lamp, and is photoexcited by the small amount of ultraviolet radiation included in the light of fluorescent lamp. The wattage of the fluorescent lamp as well as the distance between the photocatalytic thin film and the lamp are selected such that the intensity of those UV wavelengths which have a higher energy than the band gap energy of the photo-catalyst is 0.001-1 mW/cm.sup.2, preferably, 0.01-0.1 mW/cm.sup.2. The bacteria and chemical compounds deposited on the photoexcited thin film are photodecomposed.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.