Partial oxidation of methane over Fe/ZSM-5 with hydrogen peroxide generated in situ over Pd/C in the presence of halide ions.

The effect of halide ion on the catalytic activity for the aqueous-phase partial oxidation of methane with H 2 O 2 generated in situ over Pd/C was examined. Various halide ions, including F-, Cl-, Br-, and I- were compared. Among them, Br- and I- are effective for the synthesis of H 2 O 2 from H 2 and O 2 , resulting in the synthesis of methane oxygenates from methane over Fe/ZSM-5. They show different product yields as a function of their concentrations. The highest total product yields were obtained with [KBr] = 5 mM and [KI] = 0.05 mM, respectively. Compared with Br-, the highest product yield was obtained with a much lower concentration of I-, guaranteeing that no detectable leaching of metal from Fe/ZSM-5 and Pd/C was found. The total productivity was 4.64 mmol/g cat. /h over Fe/ZSM-5 at 50 ℃ with H 2 O 2 generated in situ over Pd/C from H 2 and O 2 in the presence of 0.05 mM of KI. [Display omitted] • Partial oxidation of CH 4 was examined over Fe/ZSM-5 with in situ generated H 2 O 2. • The effect of halide anion was investigated over Pd/C. • Br- and I- are effective for the synthesis of methane oxygenates from methane. • The high productivity can be achieved in the presence of KI without metal leaching. [ABSTRACT FROM AUTHOR]