Novel Bifunctional Aluminum for Oxidation of MTBE and TAME

The transformation of methyl tert-butyl ether (MTBE) and tert-amyl methyl ether (TAME) using bifunctional aluminum in the presence of dioxygen (O2) has been examined. Bifunctional aluminum, prepared by sulfating zero-valent aluminum with sulfuric acid, is an innovative extension of zero-valent metal technology. It has a dual functionality of simultaneously decomposing both reductively and oxidatively degradable contaminants. Bifunctional aluminum is capable of utilizing dioxygen through a reductive activation process to degrade oxygenates at ambient temperature and pressure where oxygenates are stable. The reductive activation of dioxygen is a new concept for oxygenate treatments for which most of oxidative technologies require strong oxidants. Results indicate that aluminum serves as a reductant to create favorable reducing conditions while sulfur-containing species, generated by the sulfation of aluminum at the metal surface, are considered to act as active sites. MTBE and TAME underwent similar parallel reaction pathways where the oxidation occurred on both sides of ether linkage. The oxidation of MTBE produced primarily tert-butyl alcohol, tert-butyl formate, methyl acetate, and acetone while tert-amyl alcohol, tert-amyl formate, methyl acetate, methyl ethyl ketone, and acetone accounted for 71.7% of the TAME lost. A postulated mechanism rationalizing the oxidation of oxygenates by bifunctional aluminum is proposed.