Synthesis process of propylene carbonate or vinyl carbonate

Abstract

The synthesis process of propylene carbonate or vinyl carbonate includes adding urea, propylene glycol or ethylene glycol in the molar amount of 1-100 times that of urea and solid alkali in the molaramount of 0.001-10 times that of urea into the reactor and reaction at the temperature of 100-200 deg.c and vacuum degree 50-600 mmHg or nitrogen blowing in the flow rate of 1-1000 ml / ml cat. min for0.5-20 hr. The present invention has the advantages of repeatable catalyst performance, material converting rate near the theoretical number, high product selectivity, less side product, etc.

Description

[0001] Field: [0002] The invention belongs to a method for synthesizing propylene carbonate or ethylene carbonate Background technique: [0003] One of the main uses of ethylene carbonate (EC) and propylene carbonate (PC) is as an efficient desulfurization and decarbonization (CO 2 ) solvents are used in industrial sectors such as natural gas purification and hydrogen production. It can also be used as a strong polar solvent in petrochemical, fiber and printing and dyeing industries. It is a good solvent for extracting petroleum fractions, raw lacquers, plasticizers and other insoluble substances. At the same time, it is also the raw material for the production of dimethyl carbonate by transesterification. In addition, using propylene carbonate as the electrolyte in the battery can withstand light, heat and chemical changes under harsh conditions, and can replace phenolic resin as a wood adhesive. It is mixed with isocyanate in a certain proportion, and wood chips can be ...

AI Technical Summary

Problems solved by technology

In the above catalyst systems, various organic solvents need to be added as a co-catalyst system, the reaction conditions are harsh (reaction temperature is 170-210°C, pressure is 6.0-12.0MPa), and the reaction time is long (generally 30min-3h ), the single-pass conversion rate of ethylene oxide is below 80%, the product yield is low (generally at 83-92%), the life-span of the catalyst is short (generally around 300h), and the catalyst, organic solvent and product are mixed together in the reaction process After the reaction, a complex separation system must be used to obtain relatively pure ethylene carbonate, and the investment in equipment is large, which makes the production cost high

At the same time, the reaction is a strong exothermic reaction, and the heat released in the reaction can easily cause the local temperature of the catalyst to be too high. At high temperatures, the organic compound catalyst system is easy to decompose or polymerize, which affects the quality of the product.