引言 汽油或柴油中的含硫化合物如硫醇、硫醚、噻吩、苯并噻吩(BT)和二苯并噻吩(DBT)燃烧后产生SOx,是酸雨和空气污染的主要来源,并可导致人产生呼吸道疾病.随着对环境保护的日益重视,各国都在不断降低轻质油品中的硫含量并制定了严格的标准.
Photochemical oxidation of thiophene in n-octane/water extraction system by using air as oxidant was studied. Results obtained here can be used as the reference of oxidative desulfurization of gasoline because thiophene is one of the main sulfur containing components in fluid catalytic cracking gasoline. A 500 W high pressure Hg lamp (wave length 365 nm, 0.19 kW · m^-2) was used as the light source for irradiation and air was introduced by a gas pump for supplying O2. Thiophene dissolved in n-octane was photodecomposed and removed into the water phase at ambient temperature and atmospheric pressure. Thiophene can be photo-oxidized directly to sulfone, sulfoxide, or ethanedioic acid, SO4^2- , CO2. The photo-oxidation kinetics of thiophene with O2 was first-order with rate constant of 4.42 × 10^s^-1 and half-time of 4.36 h. The desulfurization yield of thiophene in n-octane was 58.9% for a 5 h photo- irradiation under the conditions with air flow at 150 ml·min^-1 and water/oil ratio at 1 : 1. The sulfur content could be reduced from 800 μl·L^-1 to less than 330μl·L^-1.