Method for preparing 1,3 propylene glycol by using glycerol method

Abstract

This invention discloses a method for preparing 1, 3-propylene glycol from glycerol. The method has such advantages as high catalytic activity, mild reaction conditions, high product selectivity, high product purity, simple process. The method comprises: (1) adding 95% glycerol and 30% oxydol into a round bottom flask, setting condensing tube and drying tube, heating to 100 deg.C under stirring, and reacting for 1-3 h to obtain acetone alcohol; (2) adding acetone alcohol into a pressure reaction kettle loaded with transition oxometalate catalyst, introducing hydrogen for 4-6 h at 100-200 deg.C and 10 MPa, reacting, and rectifying to obtain 1,3-propylene glycol.

Description

technical field [0001] The present invention relates to a kind of preparation 1,3-propanediol, more specifically relate to a kind of method of glycerol method preparation 1,3-propanediol. Background technique [0002] Glycerin is an important raw material for military industry, light industry, and chemical industry. In recent years, with the continuous expansion of oleochemicals, especially biodiesel, the by-product glycerin has been seriously oversupplied and its price has fallen sharply. It is important to develop downstream products using glycerin as a raw material. It is a good method to solve the excess of glycerin, if a suitable production method of downstream products can be developed, the production cost of downstream products can be reduced. 1,3-propanediol (1,3-propanediol is called for short 1,3-PD) is a kind of important chemical raw material, and its most important use is exactly as one of the monomers of synthesizing novel polyester (such as PTT). PTT has bett...

AI Technical Summary

Problems solved by technology

Acrolein hydration is an industrialized route to produce 1,3-PD with acrolein as raw material. The disadvantage is that acrolein itself is also an important organic intermediate, and it is highly toxic, flammable and explosive, and difficult to store and transport.

The ethylene oxide carbonylation method uses ethylene oxide (referred to as EO) as a raw material, undergoes hydroformylation to obtain 3-hydroxypropionaldehyde, and then hydrogenates to obtain 1,3-PD. The disadvantage of this process is that the equipment investment is high At the same time, the high-efficiency catalyst system is complex, the production process is harsh and unstable, the selection and improvement of the highly toxic ligand, and the reaction pressure is relatively high. The hydroformylation reaction pressure is about 10MPa, and the reactor structure is quite complicated.

The condensation of formaldehyde and acetaldehyde to prepare 1,3-PD is a process in which formaldehyde and acetaldehyde are condensed into 3-HPA by catalyst KOH. After removing KOH with ion exchange resin, it is reduced with aluminum isopropoxide to obtain 1,3-PD. -PD, this method has the advantage of easy access to raw materials, but the consumption of aluminum isopropoxide is large, and the cost of producing 1,3-PD is relatively high

With the large excess of glycerin, the by-product of oleochemicals, the preparation of 1,3-propanediol by the glycerol method, that is, the preparation of 1,3-propanediol with glycerol as a raw material, becomes an ideal method for preparing 1,3-propanediol. At present, the glycerol method prepares 1, At present, 3-propanediol is generally used by biological enzyme method, but the production cost of biological enzyme method is expensive, the activity and life of the enzyme are limited, the requirements for raw materials are harsh, and the requirements for the reaction environment are also high to ensure the activity of the enzyme, so it is necessary to develop glycerol A new method for the preparation of 1,3-propanediol