Selective peroxidation of isobutane with molecular oxygen over molybdenum oxide catalyst for direct synthesis of di-tert-butyl peroxide

Abstract

The direct conversion of isobutane to high value-added chemicals is important for utilization of C4 hydrocarbon resources. This work proposed a novel route of isobutane peroxidation with molecular oxygen for green synthesis of di-tert-butyl peroxide (DTBP), widely used as polymerization initiating/crosslinking agent and diesel additive. For the first time, MoO3 was demonstrated as selective catalyst for isobutane peroxidation to DTBP. The results indicated that, the reactivity depended on the oxygen adsorption capacity of MoO3 catalyst, and the selectivity to DTBP was determined by the amount of surface Mo = O sites. During the reaction, tert-butyl hydroperoxide (TBHP) was generated from isobutane peroxidation as intermediate product, and subsequently converted to DTBP on Mo = O active sites. Under the optimized conditions, a high oxygen conversion (>95%) and stable product selectivities (DTBP ∼ 20 wt%, TBHP ∼ 13 wt%) were obtained during continuous catalyst re-usage runs. This work provides an environmental route for both C4 hydrocarbon utilization and DTBP production.