WO2013160485A1 - Procédé de préparation continue de lactide directement à partir d'acide lactique concentré - Google Patents

Procédé de préparation continue de lactide directement à partir d'acide lactique concentré Download PDF

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WO2013160485A1
WO2013160485A1 PCT/EP2013/058917 EP2013058917W WO2013160485A1 WO 2013160485 A1 WO2013160485 A1 WO 2013160485A1 EP 2013058917 W EP2013058917 W EP 2013058917W WO 2013160485 A1 WO2013160485 A1 WO 2013160485A1
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lactic acid
lactide
catalyst
zeolite
mass
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German (de)
English (en)
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Wolfgang HÖLDERLICH
Moritz VENSCHOTT
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Uhde Inventa-Fischer Gmbh
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    • C—CHEMISTRY; METALLURGY
    • C07—ORGANIC CHEMISTRY
    • C07D—HETEROCYCLIC COMPOUNDS
    • C07D319/00—Heterocyclic compounds containing six-membered rings having two oxygen atoms as the only ring hetero atoms
    • C07D319/10—1,4-Dioxanes; Hydrogenated 1,4-dioxanes
    • C07D319/12—1,4-Dioxanes; Hydrogenated 1,4-dioxanes not condensed with other rings

Definitions

  • the subject of the present invention relates to a process for the continuous, heterogeneously catalyzed direct production of L-lactide from concentrated lactic acid.
  • the aim is to circumvent the process steps of the known prepolymerization and the subsequent depolymerization and to reduce to a synthesis step. Furthermore, by-products and racemization are minimized to produce high purity L-lactide.
  • LA aqueous acid
  • L2A lactoyllactic acid, linear lactic acid dimer
  • L3A lactoyl lactoyl lactic acid, linear lactic acid trimer
  • LnA linear n-lactic acid oligomer
  • the intermediate L-lactide is unavoidable according to current state of the art or science. So that the desired mechanical properties are achieved and the already low melting point is not further reduced, the content of meso-lactide must be kept low. In addition, the achievable molecular weight also depends strongly on the purity of the lactide.
  • Monomers provide a start center for the polymerization and reduce the chain length of the polymer. For this reason, the concentration of the monomer must be kept low. Other contaminants, such as water and the linear dimer, are also inhibitors of polymerization.
  • Lactide is preferably derived from lactic acid for over one hundred years.
  • the dominant in the literature manufacturing process includes two steps, namely the pre- and depolymerization.
  • the starting material is, according to the current state of the art, obtained by fermentation, optically pure L-lactic acid.
  • the acid is fed in concentrated form to the process. There is a balance of monomer, oligomers and water.
  • the lactic acid is polycondensed.
  • water is continuously withdrawn from the system.
  • This can be realized in different ways; for example, by the usual vacuum distillation, or by means of a heteroazeotropic entraining agent or an osmotic membrane.
  • the average molecular masses of the low molecular weight polylactic acid are in the range of 600 to 5000 and can be obtained by non-catalytic means. Striking are the high reaction times of up to several hours until the desired degree of polymerization is achieved.
  • the subsequent thermal depolymerization is carried out under harsher reaction conditions.
  • the already existing vacuum is reduced to a minimum and at the same time the temperature is increased.
  • the low molecular weight polylactic acid cyclized by a
  • Polylactic acid has been used for some time in surgery and wound care.
  • the advantage of biological decomposition for example, makes one
  • the patent DE 69103159T2 describes the production of lactide in two synthesis steps. A commercially available 88% lactic acid is removed by vacuum distillation, the free water. The balance is thereby shifted to the oligomers and lactide is formed. Subsequently, the complex product spectrum, consisting of monomer (UA), dimer (L 2 A), lactide (LD), oligomers (L n A, n> 2) and water, separated by a complex vacuum distillation.
  • the pre-treatment of the lactic acid is disadvantageous.
  • the degree of polymerization is set between 1.59 and 2.63 and is thus significantly higher than the commercial 88% lactic acid.
  • the process is operated non-catalytic.
  • the influence of tin (II) octoate is investigated in Examples 12 to 14, the use of catalysts is considered superfluous.
  • the yields of a trial are unsatisfactory, with no returns.
  • the patent DE 102011088515A1 describes a two-stage homogeneous / heterogeneously catalyzed process for the preparation of D-lactide from aqueous lactic acid.
  • Example 1 aqueous D-lactic acid (15.W .-% water) at a temperature of 160 ° C and a pressure of 10 Torr (ca.13 mbar) prepolymerized to a molecular weight of 600 g / mol.
  • Example 2 the produced D-polylactic acid becomes 0.1% by weight more homogeneous
  • Zinnoctoatkatalysator mixed and reacted at 200 ° C to a gas stream.
  • the mixture is passed over a heterogeneous alumina catalyst and depolymerized to D-lactide.
  • the patent describes the catalytic effect. The highest yields are 72% and are achieved with 0.2 wt .-% Zinnoctoatkatalysator and the Aluminiumoxidkatalysatorlage.
  • the patent DE 69105144T2 also describes the synthesis of lactide.
  • the aqueous lactic acid is heated by a nitrogen carrier gas stream and brought into the gas phase, this is at temperatures of 200 "C to 220 ° C rea- linstrument.
  • the process is continuous and at atmospheric pressure.
  • alumina, silica, alumina-silica combinations, ion exchange resins and zeolites are listed.
  • Amberlyst 15 only the amorphous oxides are tested; zeolites are not further specified.
  • the used ion exchange resin catalyzes the formation of carbon monoxide, the selectivity with respect to lactide was estimated at 0%. Overall, the yields achieved are low and not competitive with the existing process.
  • Example 1 in addition to the 85% lactic acid in addition water for the hydrolysis of the oligomers is added. However, the additional amount of water reduces, compared to the pure 85% lactic acid (Example 2), the yield.
  • Evaporator temperature of 150 ° C to 225 ° C are only water and the lactic acid monomer in front gas, but not the other oligomers occurring.
  • the patent DE 69320467T2 is an extension of the two patents already described above. It includes u.a. two methods of commercial lactic acid to deprive the water. On the one hand water is removed by means of a vacuum distillation, on the other hand an entrainer is used. The separation produces lactide, but both methods are very time-consuming due to the required high reaction times of several hours. In addition, a reaction mixture of lactide, monomer, oligomers and water, which is very expensive to separate.
  • the patent WO 92/00292 describes a continuous production of lactide.
  • the educt mixture is mixed with an inert carrier gas and mixed at a temperature of 216 ° C in the gas phase. Thereafter, it flows through a reactor which is filled with catalyst.
  • the object of the present invention is to minimize the synthesis steps in the production of L-lactide from fermentatively produced, optically pure L-lactic acid.
  • the synthesis is realized by the direct, heterogeneously catalyzed conversion of concentrated aqueous lactic acid to lactide.
  • the lactic acid is not subjected to an equilibrium reaction, ie, a water separation.
  • An equilibrium shift to higher oligomers or a formation of low molecular weight polylactic acid is avoided.
  • the yields are significantly increased by the combination of heterogeneous catalysts with simultaneous vacuum operation in the selected plant construction.
  • Zeolites have been found. These achieve a high yield through a well-defined structure and acidity.
  • racemization is minimized by a mild reaction procedure in terms of temperature and pressure.
  • a process for the continuous preparation of optically pure lactide, directly from concentrated lactic acid, which is characterized in that lactic acid is heated under reduced pressure, then passes through a reaction zone filled with a heterogeneous catalyst and then the Product spectrum is cooled and separated.
  • the advantage of the process according to the invention is the direct production of lactide from concentrated lactic acid.
  • a complex pre-treatment of the aqueous lactic acid is eliminated, thus the fermentatively produced, concentrated lactic acid can be fed directly to the process.
  • the simple system construction is advantageous, this consists of a heating zone, a
  • Reaction zone consisting of a simple tubular reactor, and a cooling zone. Continuous operation reduces lactic acid residence times to a few seconds in the presence of lactide.
  • the significantly higher space-time yield of the process according to the invention reduces the energy consumption and reduces the costs incurred. Due to the low residence time and the relatively mild reaction conditions, in particular due to the reduced pressure, the racemization is kept low and is below 9% across all experiments.
  • Another advantage of the invention is the achieved product spectrum consisting of lactide, monomer and water.
  • the direct Lactidsynthese proceeds highly selectively and can be catalytically accelerated.
  • the formation of low molecular weight polylactic acid was not observed, furthermore, the conversion of oligomers is optimal and can be estimated at one hundred percent.
  • the lactic acid is heated to a temperature between 100 ° C and 300 ° C.
  • a further preferred embodiment provides that there is a negative pressure in the system, preferably from 10 mbar to 200 mbar.
  • the concentrated lactic acid is preferably a 50% to 100% lactic acid.
  • the heterogeneous catalyst is preferably a zeolite, an alumina or a silica catalyst.
  • a zeolite preferably a zeolite, an alumina or a silica catalyst.
  • the catalyst may preferably have an average acid strength and a small number of acidic centers.
  • the catalyst preferably has a high ratio of Lewis to Bronsted acidic sites.
  • the catalyst preferably has an amorphous or crystalline structure.
  • a further preferred embodiment provides that the product spectrum, consisting of lactide, monomer and water, is separated directly behind the reaction zone.
  • a separation of lactide and water is realized. It is further preferred that an inert carrier gas stream dilutes the lactic acid.
  • the conversion of the oligomers is preferably 100%, i. and the product spectrum consists only of lactide, monomer and water.
  • concentrated lactic acid and an inert carrier gas namely nitrogen
  • carbon monoxide, carbon dioxide, methane or noble gases could also be used as inert carriers.
  • the volume flow was between 0 ml / min and 80 ml / min.
  • the composition of the lactic acid can be varied. The range goes from strongly aqueous, monomer dominant 50% lactic acid to highly concentrated anhydrous lactic acid. Preferably, 80% to 100%, especially 90% to 100% lactic acid can be used.
  • the educt stream is heated in the heating zone 102 by a heat exchanger. Due to the heat in this part of the plant, the educt mixture in the
  • Gas phase to be added this depends not only on the temperature and pressure, but also on the mixture composition.
  • the system can therefore be operated in the gas or liquid phase.
  • the temperature range of 100 ° C to 300 ° C has proven itself.
  • a temperature range of 150 ° C to 250 ° C is set, very particularly advantageous is the range of 180 ° C to 240 ° C.
  • the vacuum mode has proven itself.
  • the optimum pressure range at the fixed catalyst bed is therefore between 10 mbar and
  • the heated lactic acid enters the reaction zone (103).
  • This consists of a simple tubular reactor which includes the catalyst bed.
  • the direct conversion of lactic acid to lactide can be carried out in a non-catalytic manner.
  • the reaction is advantageously accelerated by means of a catalyst.
  • Zeolites have proven to be particularly effective. In general, zeolites, especially acid, can be used as esterification catalysts. Furthermore, reactions can be controlled in a shape-selective manner by the precisely defined pore sizes of the zeolites. The formation of larger molecules, such as higher oligomers, can thus be prevented.
  • zeolites are crystalline aluminosilicates of microporous structure. Their lattices are made up of Si0 4 and Al0 4 tetrahedra. The crystal lattice forms a strictly regular pore and cavity system characteristic of any zeolite.
  • Zeolites with different structures such as the B-MFI, the HY, the beta, the L, the mordenite and the H-ZSM-5 allow the direct synthesis of lactic acid to lactide.
  • the acid strengths of the zeolites have a clear influence on the conversion of the reaction and were adjusted by the Si / Al ratio, the modulus.
  • An overview of the zeolites used is given in Table 1.
  • Table 1 Overview of the zeolites used
  • H-ZSM-5 25 HV09 / 24 Uetikon Zeocat PZ-2/25 H
  • the synthesis could be represented by an alumina catalyst (D10-10, BASF).
  • alumina catalyst D10-10, BASF.
  • the yields obtained are but in comparison to those of the zeolites low.
  • the cost savings due to the simple catalyst, consisting of alumina, is offset by the additional cost of energy, so that a comparable yield as in the zeolites is achieved.
  • zeolites are preferably used for the inventive method.
  • the mixture is cooled (104).
  • part of the flow in the first cold trap (106) is condensed.
  • Lactoyllactic acid the linear dimer of lactic acid
  • this cold trap (106) predominantly crude lactide and lactic acid are separated. The water concentration is less than 1%. Depending on the lactide concentration, liquid or crystalline phases could be deposited in the first capacitor.
  • the further, second cold trap (105) represents the total condenser. There condenses the entire remaining mixture, consisting mainly of water and traces of lactic acid monomer from. The temperatures of the two capacitors were set in the range of 0 ° C to 15 ° C. The high temperature gradient between the reactor and the capacitors allows the separation of the product spectrum and suppresses the hydrolysis.
  • racemization 100% - GC ARE A, L-LD / (GC AREA , L- LD + GC ARE A, meso- LD + GC ARE A, D-LD)
  • the analysis of the reaction mixtures was implemented by means of the H PLC. In addition, the water content of individual samples with the Karl Fischer Titration performed. The analysis of the exhaust gas flow was carried out with the aid of GC analysis and occasionally showed the formation of volatile by-products, which were continuously discharged through the dry carrier gas stream.
  • the first example serves as a reference experiment and was therefore carried out uncatalyzed.
  • the fixed catalyst bed was filled with glass beads (Roth, 1.25 mm - 1.65 mm).
  • the results should serve as a comparison for the effectiveness of the catalytic experiments in the following examples.
  • the commercial reactor was pumped with a commercially available 90% lactic acid over four hours, which corresponds to a mass of 46.9 g.
  • the volume flow of the inert gas amounted to 80 ml / min, as the medium nitrogen was used.
  • the total pressure was reduced to 150 mbar on fixed catalyst bed.
  • the temperature in both the evaporator and the reactor was 180 ° C.
  • the residence time in the reactor was calculated at about 2 sec.
  • reaction is much more selective than the numerical value indicated.
  • the chromatograms of the HPLC analysis show, besides the lactide peak and the characteristic peaks of the 90% lactic acid, no further by-products.
  • the reaction is therefore optimal, 100% selective.
  • the mass balance influences the results. For this reason, deposits in the plant and losses due to the dry inert gas increase the conversion and reduce the lactide selectivity.
  • Example 3 Examples 3 - 8
  • the individual parameters are optimized to optimize the yield.
  • the catalyst used is again the y-alumina from Example 2.
  • the trial period was another four hours.
  • the inert gas stream nitrogen
  • the temperature was 180 ° C.
  • the weight hour space velocity (WHSV) was calculated at 2.3 1 / h.
  • Striking are the comparatively high conversions of the reactions, which are directly related to the high proportion of unexplainable mass.
  • the set reduced pressure of 400 mbar 5.7 g can not be recovered and therefore not evaluated. Under atmospheric pressure, the value is even 11.2 g.
  • weight gain of the catalyst This can be estimated as 4.5 g (400 mbar) or 6.0 g (1000 mbar).
  • the direct production of lactide from lactic acid could also be achieved at the selected pressure setting of 400 mbar and 1000 mbar.
  • a pressure of 400 mbar 1.7 g of lactide could be obtained from 40.9 g of commercially available, aqueous lactic acid.
  • 1000 mbar 0.9 g of lactide were obtained from 34.4 g of lactic acid.
  • the conspicuously high mass of deposits in the laboratory reactor and the large increase in weight of the catalyst speak in favor of a reaction mode of operation in the higher negative pressure.
  • temperature plays a decisive role.
  • the range is limited on the one hand by the decomposition temperature of lactic acid upwards.
  • the reaction requires a minimum temperature, so that sales in the first place is possible.
  • the parameters were chosen for Examples 5 and 6 as follows: The runtime was four hours. The inert gas stream (nitrogen) was adjusted to 80 ml / min. The pressure was 150 mbar. The catalyst still used was the amorphous ⁇ -aluminum oxide. The catalyst mass was 5 g with a particle size spectrum of 1.25 mm to 2.00 mm. Furthermore, the temperature was reduced to 120 ° C. or increased to 240 ° C. The weight hour space velocity (WHSV) was calculated to be 2.3 l / h.
  • the total mass of the pumped 90% lactic acid was 47.7 g at the temperature setting of 240 ° C. Of these, 37.7 g of reaction mass was recovered in the first condenser. This subdivided for the first time in a crystalline, white and a liquid, milky phase. The solid phase has a very low water content of less than 1% and consists mainly of lactide and monomer. In addition, 4.7 g could be weighed in total condenser. The evaluation of the individual reaction masses gave the values shown in Table 4: IS
  • the advantage of the method according to the invention is the possibility of variation of the educt mixture. Both from weakly concentrated, oligomer-deprived lactic acid, as well as from highly concentrated lactic acid, the direct production of lactide is possible.
  • Examples 7 and 8 illustrate the wide range of applications of the structure according to the invention.
  • From a commercial 90% lactic acid two different batches were prepared. On the one hand, additional water was added to the mixture so that a 77% lactic acid can be used. On the other hand, the mixture was removed by heating with water until a 97% lactic acid was formed.
  • the two mixtures prepared were analyzed for their composition by HPLC analysis and Karl Fischer titration.
  • the 77% lactic acid contains about 23.8% water and is depleted of oligomers.
  • the degree of polymerization is about 1.17.
  • the degree of polymerization is about 1.55. Despite the water separation, the degrees of polymerization achieved are well below the usual degrees of polymerization of a PLA
  • the parameters evaluated from the above examples were adopted for Examples 7 and 8.
  • the reactor was filled with 5 g of the y-alumina catalyst.
  • the particle size was between 1.25 mm and 2.00 mm.
  • the temperature was adjusted to 240 ° C and the pressure on the catalyst fixed bed was reduced to 150 mbar.
  • the run time was four hours and the nitrogen flow rate was again set to 80 ml / min.
  • the weight hour space velocity (WHSV) was calculated at 2.3 1 / h.
  • the temperature-dependent desorption of the products is favored. Regardless of the concentration, a slight increase in the weight of the catalyst was found to be 0.2 g and 0.3 g.
  • a highly concentrated lactic acid shows better properties for the direct production of lactide than a dilute one.
  • the most important reason is the high dimer concentration in the starting mixture.
  • the linear dimer of lactic acid is considered to be the starting point for the cyclization of lactide.
  • all oligomers are hydrolyzed and thus form smaller molecules, such as dimers and monomers.
  • the newly formed dimers can form additional lactide.
  • zeolites are investigated in the following examples. Although these are more expensive compared to amorphous alumina catalysts, higher yields can be achieved. The following examples therefore include different zeolites with different structures and acid strengths.
  • the B-MFI zeolite has an average acid strength due to ion exchange and has many weak acid sites.
  • 33.6 g of reaction mass in the first condenser In the total condenser, 5.6 g of the total 46.3 g of pumped mass could be recovered.
  • Beta zeolite (Zeocat PB-1, Uetikon) has a modulus, i. H. a silicon-aluminum ratio of 150.
  • the plant was pumped 47.4 g of 90% lactic acid. Reaction masses of 37.0 g in the first condenser and 4.3 g in the total condenser were recovered.
  • the L zeolite (K zeolite L, Bayer) has a modulus (Si / Al) of 5.5.
  • Si / Al modulus
  • the zeolite with the mordenite structure (Zeocat Mordenit, Uetikon) has a modulus (Si / Al) of 15.1.
  • a total of 46.0 g of 90% lactic acid were pumped into the laboratory.
  • masses of 37.0 g and 3.3 g were weighed out.
  • the obtained values of the different zeolites again show the basic possibility of the direct synthesis of lactide from aqueous lactic acid.
  • the B-MFI zeolite used achieves a moderate conversion of 27.1% at a low selectivity of 14.7%.
  • the mass loss again affects the results obtained, the sales increase and the selectivity decreases.
  • the Not analyzable mass is due to, inter alia, deposits and decomposition reactions in the evaporation of lactic acid and can be quantified to 7.1 g. Only the zeolite knows a mass increase in the amount of
  • the B-MFI pentasil zeolite catalyzes large amounts of by-products and shows a broad product spectrum.
  • the yield is correspondingly low and is only 4.0%.
  • the yield of the alumina catalyst is 11.4%.
  • the beta zeolite achieved a turnover of 14.8%.
  • the mass loss (6.1 g) is similar to the loss of the pentasil zeolite (7.1 g), but the beta zeolite catalyzes selective lactide.
  • the catalyst weight gain was
  • the mordenite zeolite catalyzes a moderate turnover of 20.2%. Part of the turnover is due to the mass loss. The loss can be estimated at 5.7 g. Part of this mass (0.8 g) settles on the catalyst. Furthermore, a lactide selectivity of 36.7% is achieved.
  • the beta and the mordenite zeolite achieve similarly selective product spectra. These consist only of lactide,
  • the used, wide-pored HY zeolite has a particularly large cavity with a diameter of 7.4 ⁇ . This commercially available
  • Sales were more than quadrupled compared to example 1.
  • the selectivity could be increased.
  • the product which can be found preferably in the solid phase, only
  • H-ZSM-5 zeolite This has a medium pore structure, which is in a diameter of the pore of 5.6 ⁇ .
  • the different modules of the zeolites used are used to investigate the influence of the acidity.
  • H-ZSM-5 zeolites with the modules 25 (Zeocat PZ-2/25 H, Uetikon), 300 (Zeocat PZ-2/300 H, Uetikon) and 1000 (Zeocat PZ-2/1000 H, Ueticon) are used.
  • the silicon-aluminum ratio is a measure of the acidity. The more aluminum in the catalyst, the lower the modulus and the more weakly bound protons are.
  • the H-ZSM-5 zeolite with a modulus of 25 is strongly acidic, while a modulus of 1000 represents a weakly acidic catalyst with few but strongly acidic centers.
  • the preparation of the catalyst was carried out as described above, so that in each case 5 g of zeolite were used with a particle size of 1.25 mm to 2.00 mm.
  • the residence time on the catalyst was about 2 sec.
  • the parameters were taken from the above examples again.
  • the trial runtime was four hours.
  • the inert gas stream (nitrogen) was adjusted to 80 ml / min.
  • the temperature was 180 ° C and the pressure at 150 mbar.
  • the weight hour space velocity (WHSV) was calculated at 2.3 1 / h.
  • the lowest of the tested modules shows an increased mass loss. This can be calculated to 10.8 g, it already contains the mass increase of the catalyst in the amount of 1.4 g. Further, in addition to lactide, the chromatograms show other by-products which reduce selectivity in addition to mass loss.
  • the lactide selectivity is 18.0%, with the selected modulus of 25.
  • the acidity of the zeolite used is too high. Therefore, lactide can not be selectively produced and much of the lactic acid is decomposed.
  • the conversion of the medium-acid H-ZSM-5 zeolite with a modulus of 300 is 52.3% and is thus significantly higher than the turnover of the
  • the employed H-ZSM-5 zeolite with a modulus of 1000 catalyzes the highly selective direct synthesis of lactide from aqueous lactic acid. Sales are at 33.7% and again impacted by mass loss. This also reduces the lactide selectivity to 52.8%. However, apart from lactide, the product spectrum shows only lactic acid and water.
  • Example 13 and 15 the use of the HY zeolite and the H-ZSM-5 zeolite showed the highest lactide selectivities compared to the zeolites used.
  • the achieved values of 71.1% and 43.2% are to be maximized with the help of parameter optimization.
  • the temperature is increased to 210 ° C for better desorption of the products from the catalyst surface.
  • oligomer-rich 97% lactic acid is used.
  • the zeolite powder was tableted and ground to a particle size range of 1.25 mm to 2.00 mm.
  • the residence time on the catalyst was about 2 sec.
  • the parameters were taken from the above examples again.
  • the trial runtime was four hours.
  • the inert gas stream (nitrogen) was adjusted to 80 ml / min.
  • the pressure on the fixed catalyst bed was on 150 mbar regulated. To increase the selectivity further experiments were carried out with different residence times. These were realized by catalyst masses of 3 g and 5 g.
  • the weight hour space velocity (WHSV) was thus set to 3.8 h "1 and 2.3 h " 1 .
  • the pumped lactic acid masses amounted to 43.5 g (WHSV 2.3 h -1 ) and 44.5 g (WHSV 3.8 h -1 ).
  • 20.5 g or 31.6 g could be condensed to ground depending on the test.
  • the masses of the aqueous phases in the second condenser were 5.5 g and 6.7 g.
  • H-ZSM-5 150 210 LA 97 2.3 70.8 34.9 11.8

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Abstract

L'invention concerne un procédé de préparation continue, directe, à catalyse hétérogène, de L-lactide à partir d'acide lactique concentré. L'invention vise à éviter les étapes de procédé connues consistant à réaliser une prépolymérisation et une dépolymérisation consécutive, et de les réduire à une étape de synthèse. Par ailleurs, les sous-produits et la racémisation sont minimisés de manière à préparer un L-lactide très pur.
PCT/EP2013/058917 2012-04-28 2013-04-29 Procédé de préparation continue de lactide directement à partir d'acide lactique concentré WO2013160485A1 (fr)

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JP2016507545A (ja) * 2013-02-08 2016-03-10 トタル リサーチ アンド テクノロジー フエリユイ 環状エステルおよび環状アミドの製造方法
CN107473238A (zh) * 2016-06-08 2017-12-15 中国石油化工股份有限公司 一种kl分子筛及其制备方法和应用
WO2017220524A1 (fr) * 2016-06-20 2017-12-28 Total Research & Technology Feluy Procédé de production de lactide en une étape avec récupération d'eau par décantation
WO2017220522A1 (fr) * 2016-06-20 2017-12-28 Total Research & Technology Feluy Procédé de production de lactide en une étape avec récupération de chaleur
CN112010834A (zh) * 2020-09-23 2020-12-01 中触媒新材料股份有限公司 一种一步合成乙交酯的方法
CN112028869A (zh) * 2020-09-23 2020-12-04 中触媒新材料股份有限公司 一种一步合成丙交酯的方法

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JP2016507545A (ja) * 2013-02-08 2016-03-10 トタル リサーチ アンド テクノロジー フエリユイ 環状エステルおよび環状アミドの製造方法
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CN107473238B (zh) * 2016-06-08 2019-11-01 中国石油化工股份有限公司 一种kl分子筛及其制备方法和应用
JP2019521187A (ja) * 2016-06-20 2019-07-25 トタル リサーチ アンド テクノロジー フエリユイ 水をデカンテーションで回収するラクチドの単一段階製造方法
CN109563069A (zh) * 2016-06-20 2019-04-02 道达尔研究技术弗吕公司 具有热回收的单步骤丙交酯生产工艺
JP2019521186A (ja) * 2016-06-20 2019-07-25 トタル リサーチ アンド テクノロジー フエリユイ 熱回収を行なうラクチドの一段階製造方法
WO2017220522A1 (fr) * 2016-06-20 2017-12-28 Total Research & Technology Feluy Procédé de production de lactide en une étape avec récupération de chaleur
WO2017220524A1 (fr) * 2016-06-20 2017-12-28 Total Research & Technology Feluy Procédé de production de lactide en une étape avec récupération d'eau par décantation
US10745374B2 (en) 2016-06-20 2020-08-18 Total Research & Technology Feluy Single step lactide production process with recovering water by decantation
US10851078B2 (en) 2016-06-20 2020-12-01 Total Research & Technology Feluy Single step lactide production process with heat recovery
CN112010834A (zh) * 2020-09-23 2020-12-01 中触媒新材料股份有限公司 一种一步合成乙交酯的方法
CN112028869A (zh) * 2020-09-23 2020-12-04 中触媒新材料股份有限公司 一种一步合成丙交酯的方法
CN112028869B (zh) * 2020-09-23 2022-04-15 中触媒新材料股份有限公司 一种一步合成丙交酯的方法
CN112010834B (zh) * 2020-09-23 2022-04-15 中触媒新材料股份有限公司 一种一步合成乙交酯的方法

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