268
B. Michalkiewicz / Applied Catalysis A: General 394 (2011) 266–268
4. Conclusions
Methane oxidations to methyl bisulfate in oleum in presence of
iodine as a catalyst can be performed at ambient pressure. The con-
centration of ester depends on the time of the reaction (number of
passes of the liquid through the reactor), methane flow, tempera-
ture, sulfur trioxide and catalyst concentration. In order to obtain
high methyl bisulfate yield high sulfur trioxide concentration and
low methane flow is recommended. The optimum of temperature
is equal to 130 ◦C and the time of the reaction is equal to 30 h. Con-
trary to the reactors applied usually to this process [1–19], reactor
described by us can work in continuous system. Further detailed
investigation is needed.
Acknowledgement
The financial support of the Polish Ministry of Education and
Science under the contract no. N N205 3705 33 is gratefully
acknowledged
Fig. 5. The methyl bisulfate concentration in the reaction mixture vs. catalyst
concentration. Time of the reaction: 30 h, temperature: 130 ◦C, sulfur trioxide con-
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