2051-00-5Relevant articles and documents
Method for synthesizing symmetric oxalate by using dimethyl oxalate and alcohols in one step
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Paragraph 0039; 0040, (2019/01/06)
The invention relates to a method for synthesizing symmetric oxalate, in particular to a method for synthesizing the symmetric oxalate by using dimethyl oxalate and alcohols in one step. The symmetricoxalate is synthesized by using the dimethyl oxalate and the high carbon alcohols such as ethanol, propanol, butanol and pentanol as reaction raw materials and by adopting a one-step synthesis method. A catalyst used in the method is a mesoporous-microporous composite multifunctional basic catalyst, and has the advantages that mesopores significantly improve the mass transfer efficiency, while micropores significantly enlarge the specific surface area of a carrier and improve the dispersion of an active center. 10% MgO-5% Al2O3-8% Fe2O3/Na-meso-Y is used as the catalyst, the raw material ethanol and the dimethyl oxalate are enabled to be subjected to reaction under the atmospheric pressure at the temperature of 100 DEG C under the condition that the space velocity is 2 h-1, wherein the molar ratio of the raw material ethanol to the dimethyl oxalate is equal to 20 to 1; the selectivity of the product diethyl oxalate is stabilized to be about 82%, and the steady state operation is performed for 1000h; the catalytic activity and the product selectivity are basically unchanged. The whole reaction path has the characteristics of being short in synthetic route, simple in process flow and high in raw material conversion rate and product selectivity, and enabling the catalyst to be stable and non-deactivated.
Environment-friendly production method of diisopentyl oxalate without adding water-carrying agent
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Paragraph 0021; 0022; 0023, (2016/12/01)
The invention relates to an environment-friendly production method of diisopentyl oxalate without adding a water-carrying agent.Oxalic acid and isoamyl alcohol serve as raw materials, an esterification reaction is performed under the action of a catalyst, reactant isoamyl alcohol and water form azeotrope, the azeotrope is condensed and subjected to water diversion, the isoamyl alcohol subjected to water diversion is recycled, isoamyl alcohol and diisopentyl oxalate are separated after a reaction ends, and the diisopentyl oxalate product is obtained.The environment-friendly production method of diisopentyl oxalate has the advantages that by means of the azeotropic characteristic of isoamyl alcohol and water, no water-carrying agent needs to be additionally added, pollution of newly-added substances is avoided, production links are simplified, production cost is reduced, an esterification reaction is easy, and separation and purification of the product are easy; meanwhile, water in the product is separated through a membrane separation method, the process is environmentally friendly, and environment-friendly production of the whole technological process of diisopentyl oxalate is achieved.