In a stainless-steel reactor, CH4, was oxidized with 100 mL 30%SO3 oleum (2 h, 4.5 MPa, 160degreesC) containing 1 g dissolved zeolite-type ferrosilicate (Fe-ZSM-5, Si:Fe = 4 (6, 13 or 25):1) as a homogeneous catalyst, to yield esters MeOSO3 H and MeOSO3 Me and CO2 as a minor by-product. Hydrolysis gave MeOH, collected by distillation. Selectivity toward MeOH was 90%. The (4:1) was the most effective. The Fe-ZSM-5 were prepared by mixing {Fe(NO)(3).9H(2)O + H2SO4 + H2O} with {NaOH + H2O + SiO2} at pH < 4, adding aq. tetrapropylammonium bromide (TPAB), autoclaving the gel at 170degreesC in CH4 at 2 MPa, drying at 110degreesC, and calcining 5 h/550degreesC in N-2 and 3 h in air. The ZSM-5 structure was confirmed by X-rays. Trials to circumvent the solubility of Fe-ZSM-5 in oleum by resorting to compounds like Fe(NO3)(3), Fe-2(SO4)(3), SiO2, NaCl, TPAB and mixtures thereof were a complete failure.