Photochemical oxidation of thiophene by O2 in an oil/acetonitrile two-phase extraction system.
Photochemical oxidation of thiophene in an n-octane/acetonitrile extraction system using O(2) as oxidant was studied. Results obtained here can be used as a reference for desulfurization of gasoline, because thiophene is one of the main components containing sulfur in fluid catalytic cracking gasoline. A 500-W high-pressure mercury lamp was used as a light source for irradiation, and air was introduced by a gas pump to supply O(2). Thiophene dissolved in nopolar n-octane solvent was photodecomposed and removed into the polar acetonitrile phase. The desulfurization rate of thiophene in n-octane was 65.2% under photoirradiation for 5 h under the conditions of air flow at 150 mL min(-1), and V(n-octane):V(acetonitrile) = 1:1. This can be improved to 96.5% by adding 0.15 g Na-ZSM-5 zeolite into the 100-mL reaction system, which is the absorbent for O(2) and thiophene. Under such conditions, the photooxidation kinetics of thiophene with O(2) and Na-ZSM-5 zeolite is first-order with an apparent rate constant of 0.6297 h(-1) and half-time of 1.10 h. The sulfur content can be reduced from 800 microL L(-1) to 28 microL L(-1).
Li
Fa-Tang
FT
College of Science, Hebei University of Science and Technology, Shijiazhuang, China. lifatang@126.com
Zhao
Di-Shun
DS
Li
Hong-Xia
HX
Liu
Rui-Hong
RH
D000097:Acetonitriles / Q000737:chemistry; D002384:Catalysis; D005742:Gasoline; D007700:Kinetics; D009795:Octanes / Q000737:chemistry; D016877:Oxidants / Q000737:chemistry; D010100:Oxygen / Q000737:chemistry*; D010777:Photochemistry / Q000379:methods*; D013455:Sulfur / Q000737:chemistry; D013876:Thiophenes / Q000737:chemistry; D014466:Ultraviolet Rays
D000097:Acetonitriles; D005742:Gasoline; D009795:Octanes; D016877:Oxidants; D013876:Thiophenes; D013455:Sulfur; D010100:Oxygen; C026728:octane; C032159:acetonitrile