Method for continuously producing polymethoxy dimethyl ether by using methanol as original reaction material

Abstract

The invention discloses a method for continuously producing polymethoxy dimethyl ether by using methanol as an original reaction material. The method comprises: 1, performing condensation reaction on methanol serving as the original reaction material and dilute formaldehyde (return material) to produce methylal of which the mass purity is more than 95%; 2, catalytically oxidizing methylal with air in the presence of an iron-molybdenum catalyst in a separator to obtain solid formaldehyde of which the mass purity is not less than 95%; 3, melting solid formaldehyde by steam heating, then performing polymerizing etherification reaction on the solid formaldehyde and the methylal under the catalytic action of self-developed modified strong acid cation exchange resin to generate polymethoxy dimethyl ether, and dehydrating and refining the polymethoxy dimethyl ether to obtain PODE3-5 of which the mass purity is more than 99.5%. By adopting the method, the single pass yield of the polymethoxy dimethyl ether can be improved from general 40-50% to 97%, wherein the PODE3-5 yield is improved from 25% to 92%; and the method is low in equipment investment, low in energy consumption, low in production cost, simple and easy to operate, and can realize large-scale continuous industrial production.

Description

technical field [0001] The invention discloses a method for continuously producing polyoxymethylene dimethyl ether with methanol as the original reaction material. Background technique [0002] As the world's oil resources are dwindling and the demand for fuel oil is increasing, the research and development of new energy sources in various countries is increasing. [0003] In my country, with the rapid economic development and the continuous improvement of people's living standards, the demand for oil continues to increase. From a net exporter to a net importer in 1993, the degree of dependence on foreign countries has increased year by year. In 2012, it exceeded 55%. In recent years, with the rapid growth of the number of motor vehicles in my country, the consumption of oil products has increased sharply, and the pollution caused by fuel oil has become increasingly serious. At present, 80% of carbon monoxide and more than 40% of nitrogen oxides in big cities come from moto...

AI Technical Summary

Problems solved by technology

Some invention patent catalysts are corrosive, difficult to separate, generally have low catalytic activity, PODE 3-8 The selectivity is not high; some invention patent catalysts, raw material paraformaldehyde or paraformaldehyde have high cost; some invention patents have complicated process, low production efficiency, and it is difficult to realize industrialization, etc.

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