Photocatalytic oxidation of heptane in the gas-phase over TiO2.
In this paper, gas-phase photocatalytic oxidation (PCO) of heptane over UV-illuminated TiO2 was carried out at ambient temperature in a batch reactor. Complete oxidation of heptane with almost stoichiometric production of CO2 and H2O was observed. The intermediates detected were propanal, butanal, 3-heptanone, 4-heptanone and carbon monoxide. A scheme of the possible mechanism for PCO of heptane over TiO2 was suggested. Langmuir-Hinshelwood kinetics equation was obtained from the results at different initial concentrations of heptane, oxygen, moisture and light intensity. The photocatalytic activity of TiO2 can be sustained indefinitely. This can be attributed to the production of water in the system, which can replenish the consumed hydroxyl radicals.
Shang
Jing
J
Department of Environmental Science and Engineering, Jilin University, Changchun, People's Republic of China. dashanshang@yahoo.com.cn
Du
Yaoguo
Y
Xu
Zili
Z
D000465:Algorithms; D019149:Bioreactors; D002245:Carbon Dioxide / Q000378:metabolism*; D004787:Environmental Pollution / Q000517:prevention & control*; D005740:Gases; D006536:Heptanes / Q000737:chemistry* / Q000302:isolation & purification; D007700:Kinetics; D008027:Light; D008956:Models, Chemical; D010084:Oxidation-Reduction / Q000187:drug effects / Q000528:radiation effects; D010100:Oxygen / Q000008:administration & dosage; D010782:Photolysis / Q000187:drug effects / Q000528:radiation effects; D017319:Photosensitizing Agents / Q000008:administration & dosage*; D014025:Titanium / Q000008:administration & dosage*; D014466:Ultraviolet Rays; D014835:Volatilization; D014867:Water / Q000378:metabolism
D005740:Gases; D006536:Heptanes; D017319:Photosensitizing Agents; D014867:Water; D002245:Carbon Dioxide; C009495:titanium dioxide; D014025:Titanium; D010100:Oxygen