Summary of the invention
The present invention adopts reactive distillation processes, utilizes succinic acid two aqueous ammonium and esterifying agent generation catalytic esterification to generate succinate, and in reaction process, removes the ammonia G&W produced in time.Invention increases the gamma value of succinic acid two ammonium, ensure that the yield of succinate has arrived 90-100%.Meanwhile, inhibit the generation of by product, in product, the content of nitrogen element is below 1%.
Specifically, the invention provides a kind of method being prepared succinate by the esterification of succinic acid two ammonium, it comprises the following steps:
(1) first by succinic acid two aqueous ammonium and esterifying agent with the mol ratio of 1:2.5 to 1:10 and stream joins in reactor, add catalyzer simultaneously, and pour nitrogen in reactor;
(2) at the temperature of 120 DEG C-230 DEG C, make succinic acid two ammonium in reactor carry out alcoholysis reaction, reaction carries out 8 ~ 14 hours;
(3) in reaction process, the gas-phase product on reactor top, through condenser and gas-liquid separator, is separated into ammonia, esterifying agent and water, and ammonia enters Ammonia recovery system, the water that esterifying agent and water are generated except dereaction by dehumidification system, dried esterifying agent returns in reactor;
(4) after reaction terminates, still bottom product leads to azeotropic rises in rectifying tower, and adds entrainer and distill, and the bottom product obtained is corresponding succinate;
Wherein, described in step (1), the mass concentration of succinic acid two aqueous ammonium is 40% to 90%, and esterifying agent is C1 ~ C6 alkyl alcohol of straight or branched, and catalyzer is solid acid catalyst, such as, and γ-Al
2o
3, H
3pO
4-diatomite, Al
2o
3/ MgO, SiO
2-Al
2o
3, ZSM-5 molecular sieve, SAPO-34 molecular sieve etc., the add-on of catalyzer is 8 ~ 10% of succinic acid two ammonium solution, and the pressure in reactor is 0.1 ~ 1.5Mpa, and entrainer is the one in chloroform, tetracol phenixin, benzene, toluene, acetonitrile, Virahol, pyridine, n-propyl alcohol, ethyl acetate.
In above-mentioned steps (1), the mass concentration of described succinic acid two aqueous ammonium is preferably 40 ~ 80%, is more preferably 60%.
In above-mentioned steps (1), described esterifying agent is preferably methyl alcohol, ethanol, n-propyl alcohol, Virahol, propyl carbinol, isopropylcarbinol or the trimethyl carbinol, is more preferably methyl alcohol.
In above-mentioned steps (1), the mol ratio of described succinic acid two aqueous ammonium and esterifying agent is preferably 1:5 to 1:10, is more preferably 1:10.
In above-mentioned steps (1), described catalyzer is preferably SiO
2-Al
2o
3.
In above-mentioned steps (2), temperature of reaction is preferably 170 DEG C ~ 190 DEG C, is more preferably 170 DEG C.
In above-mentioned steps (2), the reaction times is preferably 10 ~ 14 hours, is more preferably 10 hours.
In above-mentioned steps (4), the pressure of described rectifying is 0.2-1.0MPa, tower top temperature 64-72 DEG C, column bottom temperature 85-120 DEG C, and distillation time is 1.5-3h.
Method of the present invention tool compared with preparing the method for succinate in prior art has the following advantages:
(1) adopt solid acid catalyst, simplify separation process, whole reaction process is simple, little to the corrosion of equipment, energy consumption is low, pollution-free.
(2) in esterification workshop section, adopt reaction distillation technique, shift out the ammonia G&W that reaction produces, improve the transformation efficiency of succinic acid two ammonium, the transformation efficiency of succinic acid two ammonium reaches more than 80%, and the selectivity of dimethyl succinate is greater than 99%.
(3) at product purification rectification section, product separation is simple, and good product quality, purity is high.
Embodiment
Below by embodiment, the present invention will be further described, but scope of the present invention is not only limited to the scope that embodiment covers.Succinic acid two ammonium described in the application is purchased from Baoji precious jade Chemical Co., Ltd..
Embodiment 1
Be added in 11.4 water by 7.6g succinic acid two ammonium, obtaining 19g succinic acid two ammonium mass concentration is the solution of 40%, by this solution and 20ml methyl alcohol and stream joins in reactor, adds catalyzer (SiO simultaneously
2-Al
2o
3) 0.6g, in reactor, pass into nitrogen, make reacting kettle inner pressure be promoted to 0.2Mpa.Temperature of reaction is 120 DEG C, and the reaction times is 10h.
The stage number of succinate azeotropy rectification column is 15 pieces, adds 16g ethyl acetate as entrainer, and reflux ratio is 1, and tower top temperature is 62-65 DEG C, and column bottom temperature is 90-100 DEG C.As shown in Figure 1, nuclear magnetic resonance spectrum as shown in Figure 2 for the mass spectrum of obtained succinate.
Experimental result sees below table 1.
Embodiment 2
Be added in 7.6 water by 7.6g succinic acid two ammonium, obtaining 15.2g succinic acid two ammonium mass concentration is the solution of 50%, by this solution and 20ml methyl alcohol and stream joins in reactor, adds catalyzer (SiO simultaneously
2-Al
2o
3) 0.6g, in reactor, pass into nitrogen, make reacting kettle inner pressure be promoted to 0.2Mpa.Temperature of reaction is 150 DEG C, and the reaction times is 10h.
The stage number of succinate azeotropy rectification column is 15 pieces, adds 16g ethyl acetate as entrainer, and reflux ratio is 1, and tower top temperature is 60-65 DEG C, and column bottom temperature is 90-100 DEG C.As shown in Figure 1, nuclear magnetic resonance spectrum as shown in Figure 2 for the mass spectrum of obtained succinate.
Experimental result sees below table 1.
Embodiment 3
Be added in 5.07 water by 7.6g succinic acid two ammonium, obtaining 12.67g succinic acid two ammonium mass concentration is the solution of 60%, by this solution and 20ml methyl alcohol and stream joins in reactor, adds catalyzer (SiO simultaneously
2-Al
2o
3) 0.6g, in reactor, pass into nitrogen, make reacting kettle inner pressure be promoted to 0.2Mpa.Temperature of reaction is 150 DEG C, and the reaction times is 10h.
The stage number of succinate azeotropy rectification column is 15 pieces, adds 16g ethyl acetate as entrainer, and reflux ratio is 1, and tower top temperature is 60-65 DEG C, and column bottom temperature is 90-100 DEG C.As shown in Figure 1, nuclear magnetic resonance spectrum as shown in Figure 2 for the mass spectrum of obtained succinate.
Experimental result sees below table 1.
Embodiment 4
Be added in 3.26 water by 7.6g succinic acid two ammonium, configuration 10.86g succinic acid two ammonium mass concentration is the solution of 70%, by this solution and 20ml methyl alcohol and stream joins in reactor, adds catalyzer (SiO simultaneously
2-Al
2o
3) 0.6g, in reactor, pass into nitrogen, make reacting kettle inner pressure be promoted to 0.2Mpa.Temperature of reaction is 150 DEG C, and the reaction times is 10h.
The stage number of succinate azeotropy rectification column is 15 pieces, adds 16g ethyl acetate as entrainer, and reflux ratio is 1, and tower top temperature is 60-65 DEG C, and column bottom temperature is 90-100 DEG C.As shown in Figure 1, nuclear magnetic resonance spectrum as shown in Figure 2 for the mass spectrum of obtained succinate.
Experimental result sees below table 1.
The result of table 1 embodiment 1-embodiment 4
Embodiment 5
Be added in 3.26 water by 7.6g succinic acid two ammonium, obtaining 10.86g succinic acid two ammonium mass concentration is the solution of 70%, adds catalyzer (SiO simultaneously
2-Al
2o
3) 0.6g, by this solution and 20ml methyl alcohol and stream joins in reactor, in reactor, pass into nitrogen, make reacting kettle inner pressure be promoted to 0.2Mpa.Temperature of reaction is 120 DEG C, and the reaction times is 10h.
The stage number of succinate azeotropy rectification column is 15 pieces, adds 16g ethyl acetate as entrainer, and reflux ratio is 1, and tower top temperature is 60-65 DEG C, and column bottom temperature is 90-100 DEG C.As shown in Figure 1, nuclear magnetic resonance spectrum as shown in Figure 2 for the mass spectrum of obtained succinate.
Experimental result sees below table 2.
Embodiment 6
Be added in 3.26g water by 7.6g succinic acid two ammonium, obtaining 10.86g succinic acid two ammonium mass concentration is the solution of 70%, by this solution and 20ml methyl alcohol and stream joins in reactor, adds catalyzer (SiO simultaneously
2-Al
2o
3) 0.6g, in reactor, pass into nitrogen, make reacting kettle inner pressure be promoted to 0.2Mpa.Temperature of reaction is 150 DEG C, and the reaction times is 10h.
The stage number of succinate azeotropy rectification column is 15 pieces, adds 16g ethyl acetate as entrainer, and reflux ratio is 1, and tower top temperature is 60-65 DEG C, and column bottom temperature is 90-100 DEG C.As shown in Figure 1, nuclear magnetic resonance spectrum as shown in Figure 2 for the mass spectrum of obtained succinate.
Experimental result sees below table 2.
Embodiment 7
Be added in 3.26g water by 7.6g succinic acid two ammonium, obtaining 10.86g succinic acid two ammonium mass concentration is the solution of 70%, by this solution and 20ml methyl alcohol and stream joins in reactor, adds catalyzer (SiO simultaneously
2-Al
2o
3) 0.6g, in reactor, pass into nitrogen, make reacting kettle inner pressure be promoted to 0.2Mpa.Temperature of reaction is 170 DEG C, and the reaction times is 10h.
The stage number of succinate azeotropy rectification column is 15 pieces, adds 16g ethyl acetate as entrainer, and reflux ratio is 1, and tower top temperature is 60-65 DEG C, and column bottom temperature is 90-100 DEG C.As shown in Figure 1, nuclear magnetic resonance spectrum as shown in Figure 2 for the mass spectrum of obtained succinate.
Experimental result sees below table 2.
Embodiment 8
Be added in 3.26g water by 7.6g succinic acid two ammonium, obtaining 10.86g succinic acid two ammonium mass concentration is the solution of 70%, by this solution and 20ml methyl alcohol and stream joins in reactor, adds catalyst A l simultaneously
2o
3/ MgO 0.6g, passes into nitrogen in reactor, makes reacting kettle inner pressure be promoted to 0.2Mpa.Temperature of reaction is 190 DEG C, and the reaction times is 10h.
The stage number of succinate azeotropy rectification column is 15 pieces, adds 16g ethyl acetate as entrainer, and reflux ratio is 1, and tower top temperature is 60-65 DEG C, and column bottom temperature is 90-100 DEG C.As shown in Figure 1, nuclear magnetic resonance spectrum as shown in Figure 2 for the mass spectrum of obtained succinate.
Experimental result sees below table 2.
The result of table 2 embodiment 5-embodiment 8
Embodiment 9
Be added in 3.26g water by 7.6g succinic acid two ammonium, obtaining 10.86g succinic acid two ammonium mass concentration is the solution of 70%, by this solution and 20ml methyl alcohol and stream joins in reactor, adds catalyzer (SiO simultaneously
2-Al
2o
3) 0.6g, in reactor, pass into nitrogen, make reacting kettle inner pressure be promoted to 0.2Mpa.Temperature of reaction is 170 DEG C, and the reaction times is 8h.
The stage number of succinate azeotropy rectification column is 15 pieces, adds 16g ethyl acetate as entrainer, and reflux ratio is 1, and tower top temperature is 60-65 DEG C, and column bottom temperature is 90-100 DEG C.As shown in Figure 1, nuclear magnetic resonance spectrum as shown in Figure 2 for the mass spectrum of obtained succinate.
Experimental result sees below table 3.
Embodiment 10
Be added in 3.26g water by 7.6g succinic acid two ammonium, obtaining 10.86g succinic acid two ammonium mass concentration is the solution of 70%, by this solution and 20ml methyl alcohol and stream joins in reactor, adds catalyzer (SiO simultaneously
2-Al
2o
3) 0.6g, in reactor, pass into nitrogen, make reacting kettle inner pressure be promoted to 0.2Mpa.Temperature of reaction is 170 DEG C, and the reaction times is 10h.
The stage number of succinate azeotropy rectification column is 15 pieces, adds 16g ethyl acetate as entrainer, and reflux ratio is 1, and tower top temperature is 60-65 DEG C, and column bottom temperature is 90-100 DEG C.As shown in Figure 1, nuclear magnetic resonance spectrum as shown in Figure 2 for the mass spectrum of obtained succinate.
Experimental result sees below table 3.
Embodiment 11
Be added in 3.26 water by 7.6g succinic acid two ammonium, obtaining 10.86g succinic acid two ammonium mass concentration is the solution of 70%, by this solution and 20ml methyl alcohol and stream joins in reactor, adds catalyzer (SiO simultaneously
2-Al
2o
3) 0.6g, in reactor, pass into nitrogen, make reacting kettle inner pressure be promoted to 0.2Mpa.Temperature of reaction is 170 DEG C, and the reaction times is 12h.
The stage number of succinate azeotropy rectification column is 15 pieces, adds 16g ethyl acetate as entrainer, and reflux ratio is 1, and tower top temperature is 60-65 DEG C, and column bottom temperature is 90-100 DEG C.As shown in Figure 1, nuclear magnetic resonance spectrum as shown in Figure 2 for the mass spectrum of obtained succinate.
Experimental result sees below table 3.
Embodiment 12
Be added in 3.26 water by 7.6g succinic acid two ammonium, obtaining 10.86g succinic acid two ammonium mass concentration is the solution of 70%, by this solution and 20ml methyl alcohol and stream joins in reactor, adds catalyzer (SiO simultaneously
2-Al
2o
3) 0.6g, in reactor, pass into nitrogen, make reacting kettle inner pressure be promoted to 0.2Mpa.Temperature of reaction is 170 DEG C, and the reaction times is 14h.
The stage number of succinate azeotropy rectification column is 15 pieces, adds 16g ethyl acetate as entrainer, and reflux ratio is 1, and tower top temperature is 60-65 DEG C, and column bottom temperature is 90-100 DEG C.As shown in Figure 1, nuclear magnetic resonance spectrum as shown in Figure 2 for the mass spectrum of obtained succinate.
Experimental result sees below table 3.
The result of table 3 embodiment 9-embodiment 12
As can be seen from the above results, when succinic acid two aqueous ammonium concentration is 70%, temperature of reaction is 170 DEG C, and the reaction times is 10 constantly little, and the by product that method as herein described obtains is few, and the cost of raw material is low, and product purity is high.