Separation and oxidative degradation of organic pollutants in aqueous systems by pervaporation and vacuum–ultraviolet-photolysis

Degradation of 2,4-dihydroxibenzoic acid by vacuum UV process in aqueous solution: Kinetic, identification of intermediates and reaction pathway

“…Absorption of water increases steadily from approximately 190 to 120 nm and its electronic excitation in this spectral region induces its homolysis leading to the production of a large amount of hydrogen radicals (H • ) and HO • [7]. For this purpose, vacuum ultra-violet (V-UV) lamps have been used for water homolysis in water treatment [8][9][10][11][12] and gaseous stream treatment [13][14][15][16]. This kind of lamp is a very interesting and powerful source of HO • radicals [7,17] with a considerable potential for application.…”

Mercury-free sources of VUV/UV radiation: application of modern excimer lamps (excilamps) for water and air treatment

“…The penetration depth of 172 nm radiation into a gas phase saturated with water vapor was spectroscopically determined to be approximately 6 mm and 28.5 mm into 100% dry oxygen at a pressure of 100 mbar, respectively (Baus et al 2002). The irradiation of air or oxygen with 172 nm radiation leads immediately to the production of ozone (László et al 1998), and the photolysis of water vapor at λ of 165 nm yields H 2 , O 2 , and H 2 O 2 (Chen and Taylor 1957).…”

“…Recently, Gassiot et al (1998) and Baus et al (2002) demonstrated the efficient oxidative degradation of tetrahydrofuran (THF) in the gas phase using an annular photochemical reactor equipped with two Xe 2 * excimer radiation sources of 0.9 m length each and a maximum electric input power of 1.5 kW per lamp. Lopez-Gejo et al (2004) demonstrated the efficient removal of thiophene from the gas phase via oxidation and mineralization by VUV irradiation with a Xe 2 * excilamp (200 W).…”

A novel membrane reactor for ozone water treatment

“…They used a biological membrane reactor to extract and degrade toxic organic pollutants from industrial wastewater. Baus et al [25] described a novel hybrid treatment process that uses membrane pervaporation to separate and remove volatile organic compounds from an industrial wastewater and the pervaporated pollutants were destroyed by gas phase, UV photolysis. Many researchers have investigated the possible substitution of a catalytic membrane reactor for the conventional three-phase reactor.…”