PHOTOCATALYTIC DEGRADATION OF METHYL-TERT-BUTYL ETHER IN TIO2 SLURRIES - A PROPOSED REACTION SCHEME

Among the various alternatives to enhance the octane rating of gasolin e, methyl-tert-butyl ether (MTBE) has become increasingly the compound of choice. Due to its high solubility in water there are some environ mental concerns related to the remediation of waters contaminated with gasoline containing MTBE. Although MTBE is difficult to treat economi cally with conventional techniques, it has been found to be readily de graded photocatalytically. In batch TiO2 slurries and under the experi mental conditions used in these experiments MTBE degradation proceeded with an initial pseudo first-order rate constant of 1.2 x 10(-3) s(-1 ). The primary by-products of this reaction have been identified as t- butyl formate and t-butyl alcohol, both of which are also readily degr aded photocatalytically, albeit at slightly slower rates than MTBE. Ma ss balance calculations have shown that MTBE is virtually completely m ineralized and a reaction scheme is proposed.