Industrial processes dimethyl oxalate

In addition to the Hquid-phase -butyl nitrite (BN) process, UBE Industries has estabHshed an industrial gas-phase process using methyl nitrite (50—52). The oudine of the process is described in Eigure 4 (52). This gas-phase process is operated under lower reaction pressure (at atmospheric pressure up to 490 kPa = 71 psi) and is more economical than the Hquid-phase process because of the foUowing reasons owing to the low pressure operation, the consumption of electricity is largely reduced (—60%) dimethyl oxalate (DMO) formation and the methyl nitrite (MN) regeneration reaction are mn... 

Industrial processes for dialkyl oxalate and dimethyl carbonate from CO, alcohol and oxygen catalyzed by Pd have been developed by Ube Industries in Japan [2]. 

Carbonylation of alcohol group, methanol to dimethyl carbonate (DMC) and dimethyl oxalate (DMO), phenol to diphenyl carbonate (DPC), is very important chemical process in the current chemical industry. Dialkoxyl carbonate is key material for phosgene free process. The electrocarbonylation has great advantages to compare with a conventional catalytic carbonylation with O2. A particular advantage of electrocarbonylation is to be able to suppress CO2 formation by oxidation of CO because oxidizing power can be controlled as finely as one millivolt and there is no oxygen. 

More recently, Ube Industries have published an indirect process to carbonylate methanol oxidatively to dimethyl oxalate utilizing nitrous acid methyl ester as the oxidant. A supported Pd/Fe catalyst is used and methyl nitrite can be generated either in situ or in a separate reactor from methanol and NO [74] ... 

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