CN113429260B - Method for preparing propylene glycol by catalytic hydrogenolysis of glycerol - Google Patents
Method for preparing propylene glycol by catalytic hydrogenolysis of glycerol Download PDFInfo
- Publication number
- CN113429260B CN113429260B CN202110564794.4A CN202110564794A CN113429260B CN 113429260 B CN113429260 B CN 113429260B CN 202110564794 A CN202110564794 A CN 202110564794A CN 113429260 B CN113429260 B CN 113429260B
- Authority
- CN
- China
- Prior art keywords
- propylene glycol
- bed reactor
- glycerol
- slurry bed
- hydrogenolysis
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
Images
Classifications
-
- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C29/00—Preparation of compounds having hydroxy or O-metal groups bound to a carbon atom not belonging to a six-membered aromatic ring
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
- B01J23/00—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00
- B01J23/38—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00 of noble metals
- B01J23/40—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00 of noble metals of the platinum group metals
- B01J23/42—Platinum
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
- B01J23/00—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00
- B01J23/38—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00 of noble metals
- B01J23/54—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00 of noble metals combined with metals, oxides or hydroxides provided for in groups B01J23/02 - B01J23/36
- B01J23/56—Platinum group metals
- B01J23/64—Platinum group metals with arsenic, antimony, bismuth, vanadium, niobium, tantalum, polonium, chromium, molybdenum, tungsten, manganese, technetium or rhenium
- B01J23/652—Chromium, molybdenum or tungsten
- B01J23/6527—Tungsten
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
- B01J23/00—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00
- B01J23/70—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00 of the iron group metals or copper
- B01J23/76—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00 of the iron group metals or copper combined with metals, oxides or hydroxides provided for in groups B01J23/02 - B01J23/36
- B01J23/80—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00 of the iron group metals or copper combined with metals, oxides or hydroxides provided for in groups B01J23/02 - B01J23/36 with zinc, cadmium or mercury
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
- B01J23/00—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00
- B01J23/70—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00 of the iron group metals or copper
- B01J23/76—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00 of the iron group metals or copper combined with metals, oxides or hydroxides provided for in groups B01J23/02 - B01J23/36
- B01J23/84—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00 of the iron group metals or copper combined with metals, oxides or hydroxides provided for in groups B01J23/02 - B01J23/36 with arsenic, antimony, bismuth, vanadium, niobium, tantalum, polonium, chromium, molybdenum, tungsten, manganese, technetium or rhenium
- B01J23/85—Chromium, molybdenum or tungsten
- B01J23/888—Tungsten
-
- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C29/00—Preparation of compounds having hydroxy or O-metal groups bound to a carbon atom not belonging to a six-membered aromatic ring
- C07C29/60—Preparation of compounds having hydroxy or O-metal groups bound to a carbon atom not belonging to a six-membered aromatic ring by elimination of -OH groups, e.g. by dehydration
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
- Y02P20/00—Technologies relating to chemical industry
- Y02P20/50—Improvements relating to the production of bulk chemicals
- Y02P20/52—Improvements relating to the production of bulk chemicals using catalysts, e.g. selective catalysts
Landscapes
- Chemical & Material Sciences (AREA)
- Organic Chemistry (AREA)
- Engineering & Computer Science (AREA)
- Materials Engineering (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
Abstract
The invention discloses a method for preparing propylene glycol by catalytic hydrogenolysis of glycerol. It comprises the following steps: 1) Adding a powdered metal hydrogenolysis catalyst and a glycerol aqueous solution into a slurry bed reactor; 2) Continuously introducing hydrogen into the slurry bed reactor in the step 1) to perform hydrogenolysis reaction to generate propylene glycol, wherein the introduced hydrogen enables the generated propylene glycol to be carried out of the slurry bed reactor; 3) Pumping the glycerol aqueous solution into the slurry bed reactor for carrying out hydrogenolysis reaction in the step 2), and maintaining the liquid level height in the slurry bed reactor to continuously carry out the step 2) to obtain the propylene glycol. The invention can effectively overcome the influence of internal and external transmission on the selectivity of the 1, 2-propylene glycol and the 1, 3-propylene glycol when the reaction is carried out in the slurry bed reactor, and the generated propylene glycol is carried out of the reaction system by hydrogen in time, thereby effectively avoiding the occurrence of secondary hydrogenolysis reaction and obviously improving the total selectivity of the 1, 2-propylene glycol and the 1, 3-propylene glycol.
Description
Technical Field
The invention relates to a method for preparing propylene glycol by catalytic hydrogenolysis of glycerol, belonging to the field of glycerol processing.
Background
With the rapid development of the biomass diesel in recent years, the byproduct glycerol is abundant, and the global annual yield exceeds 400 million tons. Therefore, development of a new approach for efficient transformation and utilization of glycerol is urgently needed. Under the condition of hydrogen, the glycerol can be efficiently converted into high value-added chemicals such as 1, 2-propylene glycol, 1, 3-propylene glycol and the like. Wherein, the 1, 2-propylene glycol is an important raw material of unsaturated polyester, epoxy resin, polyurethane resin and surfactant, and can be widely used as a moisture absorbent, an antifreeze and a lubricant in the industries of food, medicine and cosmetics; the 1, 3-propylene glycol is widely applied as an important chemical intermediate, is mainly used as a monomer for synthesizing polyester fiber PTT (poly (1, 3-propylene glycol terephthalate)), and the PTT fiber has the characteristics of terylene, chinlon and acrylon, has good antifouling property, is easy to dye, has soft hand feeling and high elasticity, and is very suitable for high-grade clothing fabrics. The reaction scheme for the hydrogenolysis of glycerol to propylene glycol is shown in figure 1.
Although the production of 1, 2-propanediol and 1, 3-propanediol by using glycerol, which is a byproduct of biodiesel, as a raw material has a high economic prospect, the production of the 1, 2-propanediol and the 1, 3-propanediol is very challenging in the aspects of catalyst and process development. Glycerol contains three adjacent hydroxyl groups in the molecule, with selective hydrogenolysis of the primary hydroxyl group yielding 1, 2-propanediol and hydrogenolysis of the secondary hydroxyl group yielding 1, 3-propanediol. However, the 1, 2-propanediol and 1, 3-propanediol produced may undergo secondary hydrogenolysis reactions to produce by-products such as n-propanol and isopropanol.
At present, the preparation of the propylene glycol by the hydrogenolysis of the glycerol mostly adopts a batch autoclave process or a continuous trickle bed process. Patent CN201410284148.2 discloses a method for preparing propylene glycol by catalytic hydrogenolysis of biodiesel-based crude glycerol, in which crude glycerol with a well-adjusted pH value or an aqueous solution thereof is put into a high-pressure reaction kettle, and a catalyst is added to react under a proper condition to obtain propylene glycol. The kettle type batch hydrogenolysis process has the advantages that the powder catalyst with small particles can be adopted, the stirring is strong, and the influence of the internal diffusion of the catalyst on the secondary hydrogenolysis reaction can be inhibited to the maximum extent. The method has the disadvantages of difficult realization of continuous operation, low gas-liquid contact surface, large liquid film thickness, difficult hydrogen mass transfer and low glycerol conversion efficiency. In addition, the generated 1, 2-propylene glycol and 1, 3-propylene glycol can not leave the reaction system in time, so that secondary hydrogenolysis reaction is difficult to avoid, and the side product propanol is more.
Patent CN200710020031.3 discloses a method for continuously preparing 1, 2-propylene glycol by hydrogenation of glycerin catalyst, which uses a catalyst containing copper and zinc and manganese and/or aluminum, glycerin and hydrogen are simultaneously and continuously introduced from the upper end of a reactor, catalytic hydrogenation reaction is carried out under certain conditions, and reaction products are continuously output and collected from the lower end of the reactor. The continuous trickle bed process is beneficial to hydrogen mass transfer and can obtain better glycerol conversion rate. However, in order to prevent the bed pressure difference from being too large, the trickle bed process generally adopts a catalyst with a larger particle size, and the trickle bed process has no disturbance and small turbidity, so that the mass transfer of the glycerol and the products in the catalyst is slow, and the 1, 2-propylene glycol and the 1, 3-propylene glycol are easy to generate secondary hydrogenolysis reaction to generate the n-propanol and the isopropanol.
Therefore, the batch kettle type process and the continuous trickle bed reaction process developed at present are difficult to avoid the occurrence of secondary hydrogenolysis reaction of propylene glycol and a plurality of byproducts. To improve the selectivity of 1, 2-propanediol and 1, 3-propanediol, the conversion of glycerol is generally strictly controlled to be kept at a low level (< 40%) to suppress the occurrence of side reactions, while a large amount of unconverted glycerol needs to be separated and then converted, increasing the separation cost.
Disclosure of Invention
The invention aims to provide a method for preparing propylene glycol by the catalytic hydrogenolysis of glycerol.
The invention can effectively overcome the influence of internal and external transmissions on the selectivity of the 1, 2-propylene glycol and the 1, 3-propylene glycol, and the generated 1, 2-propylene glycol and the 1, 3-propylene glycol can be carried out of a reaction system by hydrogen in time, thereby effectively avoiding the occurrence of secondary hydrogenolysis reaction, obviously improving the total selectivity of the 1, 2-propylene glycol and the 1, 3-propylene glycol, and particularly leading the total selectivity of the 1, 2-propylene glycol and the 1, 3-propylene glycol to be as high as 83.5 percent.
The invention provides a method for preparing propylene glycol by catalytic hydrogenolysis of glycerol, which comprises the following steps: 1) Adding a powdered metal hydrogenolysis catalyst and a glycerol aqueous solution into a slurry bed reactor;
2) Continuously introducing hydrogen into the slurry bed reactor in the step 1), carrying out hydrogenolysis reaction to generate propylene glycol, and carrying the generated propylene glycol out of the slurry bed reactor by the introduced hydrogen;
3) Pumping the glycerol aqueous solution into the slurry bed reactor for carrying out hydrogenolysis reaction in the step 2), and maintaining the liquid level height in the slurry bed reactor to continuously carry out the step 2) to obtain the propylene glycol.
In the invention, the powdered metal hydrogenolysis catalyst and the glycerol aqueous solution are mixed or directly added into a slurry bed reactor for reaction.
In the invention, the slurry bed reactor is a conventional reactor known in the field, and specifically comprises key components such as a gas feeding hole, a gas distributor, a gas-liquid separator, a liquid feeding hole and the like.
In the above method, the metal hydrogenolysis catalyst is at least one selected from the group consisting of a copper-based catalyst, a platinum-based catalyst, and an iridium-rhenium catalyst.
In the present invention, the metal hydrogenolysis catalyst is a conventional catalyst well known in the art, and is prepared according to a method well known in the art.
The composition of the platinum-based catalyst is given below by way of example:
the platinum-based catalyst is prepared by adopting a conventional impregnation method, and mainly comprises three components of hydrogenation component platinum, metal oxidation auxiliary agent and carrier. In the platinum-based catalyst, the metal oxidation promoter may be selected from one or more of oxides of Ca, mo, W, zn, for example, the promoter may be CaO, mo 3 O 4 、WO 3 And/or ZnO; in the platinum-based catalyst, the support may be selected from one or more of oxides of Ti, zr, al, si. For example, the support may be ZrO 2 、Al 2 O 3 And TiO 2 2 Or SiO 2 One or more of (a).
In some further preferred embodiments, the platinum loading in the platinum-based catalyst is from 0.5wt% to 5.0wt% (relative to the support oxide), preferably from 1wt% to 5wt%, for example, 1wt%, 2wt%, 2.5wt%, 3wt%, 4wt%, 5wt%, or any value therebetween. The platinum-based catalyst has an oxide promoter loading of 5wt% to 15.0wt% (relative to the support oxide), preferably 6wt% to 11wt%, for example 6wt%, 7wt%, 8wt%, 9wt%, 10wt% or any value therebetween.
In some further preferred embodiments, the platinum-based catalyst is prepared using methods conventional in the art (e.g., impregnation methods) comprising: a solution of a water-soluble salt of the metal is prepared and then impregnated on an oxide support, followed by drying and calcination.
For example, with Pt-WO 3 /Al 2 O 3 Catalyst example, pt-WO 3 /Al 2 O 3 Typical impregnation procedures for the catalyst may include (but are not limited to): preparing a mixed aqueous solution of water-soluble platinum salt and tungsten salt with a certain concentration, wetting a powdered oxide carrier by deionized water, pouring the prepared mixed aqueous solution of platinum salt and tungsten salt onto the wetted oxide carrier, stirring, soaking at room temperature for 20-40 h, drying in an oven at 60-120 ℃ for 8-24 h after soaking, and roasting in a muffle furnace at 350-500 ℃ for 4-8 h.
In the above method, the particle size of the metal hydrogenolysis catalyst may be 100 to 400 mesh, preferably 200 to 300 mesh.
The mass ratio of the glycerol to the metal hydrogenolysis catalyst in step 1) of the above method may be 5 to 50:1.
the mass ratio of the glycerol to the metal hydrogenolysis catalyst in the step 1) of the method may be, specifically, 10 to 40:1, more specifically 10 to 20: 1. 20 to 30, or 10 to 30, and in a specific embodiment can be 12: 1. 10:1 or 8.
In step 2) of the above method, the hydrogenolysis reaction conditions are as follows: introducing the hydrogen with the flow rate of 50-800 mL/min;
the pressure can be 0.5-8.0 MPa; the temperature may be 110 to 200 ℃.
In the above method, the pressure may be specifically 1.0 to 6MPa, more specifically 2MPa, 4MPa, 5MPa, 6MPa or 2.0 to 6MPa; the temperature may be in the range of 120 to 180 deg.C, more specifically 120 deg.C, 140 deg.C, 150 deg.C, 180 deg.C.
In the step 2) of the above method, the hydrogen flow rate may be specifically 100 to 600mL/min, and more specifically 100mL/min, 200mL/min, 300mL/min, 400mL/min, 500mL/min, or 600mL/min.
In the steps 1) and 3) of the method, the mass concentration of the glycerol aqueous solution can be 50-90%, specifically 50%, 60%, 70%, 80% or 50-80%;
the pumping flow rate of the glycerol aqueous solution can be 0.005-5 mL/min, specifically 0.005mL/min, 0.01mL/min, 0.015mL/min, 0.02mL/min, 0.025mL/min, 0.03mL/min or 0.005-3 mL/min.
In the above method, the liquid level in the slurry bed reactor is maintained at 2/3 to 4/5 of the height of the slurry bed reactor, and specifically, may be 2/3, 7/10, or 4/5.
The invention has the following advantages:
(1) The slurry bed reactor provided by the invention is provided with the gas distributor, hydrogen enters the reactor through the gas distributor to form bubbles with extremely small particle size, the gas-liquid contact area is high, the hydrogen mass transfer resistance is low, and the glycerol conversion efficiency can be obviously improved;
(2) The internal disturbance of the slurry bed reactor developed by the invention can reduce the influence of external diffusion on product distribution to the maximum extent, and is beneficial to improving the glycerol conversion efficiency;
(3) The invention adopts the powdery catalyst, eliminates the influence of internal diffusion of the catalyst to the maximum extent and is beneficial to improving the yield of the propylene glycol;
(4) The hydrogen circulation amount of the glycerin hydrogenolysis process of the slurry bed developed by the invention is large, and the 1, 2-propylene glycol (188 ℃) and the 1, 3-propylene glycol (210 ℃) with relatively low boiling points generated in the reaction process can be timely taken away from the reactor, so that the occurrence of secondary hydrogenolysis reaction is inhibited;
(5) In the process for hydrogenolysis of the glycerin in the slurry bed developed by the invention, only a small amount of glycerin is carried out of the reactor by hydrogen because the boiling point of the glycerin serving as the reaction raw material is higher (290 ℃), and most of the glycerin is continuously left in the reactor for continuous reaction, so that higher total selectivity of the propylene glycol is obtained under high glycerin conversion rate, and the glycerin recycling amount is reduced.
(6) The glycerin hydrogenolysis process of the slurry bed developed by the invention can bring the generated heat out of the reaction system in time, and is beneficial to avoiding the local overheating of the reactor.
Drawings
FIG. 1 is a reaction scheme for the hydrogenolysis of glycerol to propylene glycol.
Detailed Description
The experimental procedures used in the following examples are all conventional procedures unless otherwise specified.
Materials, reagents and the like used in the following examples are commercially available unless otherwise specified.
Glycerol, ammonium metatungstate, tetraammineplatinum dichloride, alumina and the like used in the following examples are all commercially available, and quartz sand of 20 to 40 mesh is all commercially available. The experimental methods without specifying specific conditions in the following examples were selected according to the conventional methods and conditions, or according to the commercial instructions.
In the following procedure, comparative example 1 was carried out in a conventional 50ml autoclave, comparative example 2 in a conventional trickle bed and examples 1-6 in a 1L slurry bed reactor. The reaction liquid product was detected and analyzed by Agilent 6890 using AB-InoWax (30 m. Times.0.32 mm. Times.0.5 μm) as a test column, and each substance to be detected was quantified by an external standard method.
In the following examples, pt-WO 3 /Al 2 O 3 The general impregnation procedure for the catalyst is specified below: preparing a mixed aqueous solution of water-soluble platinum salt and tungsten salt with a certain concentration, and simultaneously adding a powdery oxide carrier (Al) 2 O 3 ) Wetting with deionized water, pouring the prepared mixed aqueous solution of platinum salt and tungsten salt onto the wetted oxide carrier, stirring, soaking at room temperature for 20-40 h, drying in an oven at 60-120 ℃ for 8-24 h after soaking, and roasting in a muffle furnace at 350-500 ℃ for 4-8 h;
Pt/Al 2 O 3 preparation method of catalyst and Pt-WO 3 /Al 2 O 3 The catalyst preparation is basically the same, and the difference is that no tungsten salt is added during the preparation;
Cu-WO 3 /Al 2 O 3 preparation method of catalyst and Pt-WO 3 /Al 2 O 3 The preparation of the catalyst is basically the same, and the difference is that the platinum salt is replaced by copper salt during the preparation;
Cu-ZnO/Al 2 O 3 preparation method of catalystMethod and Pt-WO 3 /Al 2 O 3 The catalyst is prepared basically in the same way, and the difference is that the platinum salt is replaced by copper salt and the tungsten salt is replaced by zinc salt during preparation.
Examples 1,
Weighing Pt-WO 3 /Al 2 O 3 25g (200-300 mesh) of catalyst and 500 g of 60wt% aqueous glycerol solution were fed into a 1L slurry bed reactor. The reaction temperature is set to be 140 ℃, the reaction pressure is 5MPa, pure hydrogen is adopted as the hydrogen atmosphere, and the flow rate is 100mL/min. After the hydrogenolysis reaction is started, 60wt% of glycerol aqueous solution is input into the slurry bed reactor at the flow rate of 0.005ml/min, the liquid level height in the slurry bed reactor is maintained to be 2/3 of the total height of the slurry bed reactor, so as to continuously carry out the hydrogenolysis reaction, and obtain the propylene glycol. After 24h of reaction, a sample was taken from the gas-liquid separator for analysis. The reaction results are shown in Table 1.
Pt-WO 3 /Al 2 O 3 The catalyst has Pt content of 2% and is prepared through conventional soaking process.
Examples 2,
Weighing Cu-WO 3 /Al 2 O 3 35g (100-400 mesh) of catalyst, 350 g of 80wt% aqueous glycerol solution were fed into a 1L slurry bed reactor. The reaction temperature is set to be 140 ℃, the reaction pressure is 6MPa, pure hydrogen is adopted as the hydrogen atmosphere, and the flow rate is 200mL/min. After the initiation of the hydrogenolysis reaction, an 80wt% aqueous solution of glycerin was fed into the reactor at a flow rate of 0.01ml/min to maintain the height of the liquid surface in the reactor at 4/5 of the total height, to continuously conduct the hydrogenolysis reaction to obtain propylene glycol. After 24h of reaction, a sample was taken from the gas-liquid separator for analysis. The reaction results are shown in Table 1.
Cu-WO 3 /Al 2 O 3 The Cu content of the catalyst is 5 percent, and the catalyst is prepared by a conventional impregnation method.
Examples 3,
Weighing Cu-ZnO/Al 2 O 3 40g (100-400 mesh) of catalyst and 600 g of 70wt% aqueous glycerol solution were fed into a 1L slurry bed reactor. The reaction temperature is set to be 150 ℃, the reaction pressure is set to be 4MPa, pure hydrogen is adopted in the hydrogen atmosphere, and the flow rate is 300mL/min. After the start of the hydrogenolysis reaction, a 70wt% aqueous solution of glycerin was fed into the reactor at a flow rate of 0.015ml/minThe hydrogenolysis reaction was continued while maintaining the height of the liquid level in the reactor at 7/10 of the total height to obtain propylene glycol. After 24h of reaction, a sample was taken from the gas-liquid separator for analysis. The reaction results are shown in Table 1.
Cu-ZnO/Al 2 O 3 The Cu content of the catalyst is 4 percent, and the catalyst is prepared by a conventional impregnation method.
Examples 4,
Weighing Pt/Al 2 O 3 20g (100-400 meshes) of catalyst and 400 g of 60wt% glycerol aqueous solution are added into a 1L slurry bed reactor. The reaction temperature is set to be 180 ℃, the reaction pressure is 1MPa, pure hydrogen is adopted in the hydrogen atmosphere, and the flow rate is 400mL/min. After the hydrogenolysis reaction was started, a 60wt% aqueous solution of glycerin was fed into the reactor at a flow rate of 0.02ml/min, and the liquid level in the reactor was maintained at 2/3 of the total height to continue the hydrogenolysis reaction to obtain propylene glycol. After 24h of reaction, a sample was taken from the gas-liquid separator for analysis. The reaction results are shown in Table 1.
Pt/Al 2 O 3 The catalyst has Pt content of 2% and is prepared through conventional soaking process.
Examples 5,
Weighing Pt-WO 3 /Al 2 O 3 30g (100-400 mesh) of catalyst and 600 g of 50wt% aqueous glycerol solution were fed into a 1L slurry bed reactor. Setting the reaction temperature at 120 ℃, the reaction pressure at 2MPa, and adopting pure hydrogen in the hydrogen atmosphere at the flow rate of 500mL/min. After the initiation of the hydrogenolysis reaction, a 50wt% aqueous solution of glycerin was fed into the reactor at a flow rate of 0.025ml/min to maintain the height of the liquid level in the reactor at 4/5 of the total height, to continue the hydrogenolysis reaction to obtain propylene glycol. After 24h of reaction, a sample was taken from the gas-liquid separator for analysis. The reaction results are shown in Table 1.
Pt-WO 3 /Al 2 O 3 The Pt content of the catalyst is 2 percent, and the catalyst is prepared by a conventional impregnation method.
Examples 6,
Weighing Pt-WO 3 /Al 2 O 3 25g (200-300 mesh) of catalyst and 500 g of 60wt% aqueous glycerol solution were fed into a 1L slurry bed reactor. Setting the reaction temperature at 140 deg.C, the reaction pressure at 5MPa, pure hydrogen in hydrogen atmosphere at 600mL/min. After the hydrogenolysis reaction was started, 60wt% glycerol aqueous solution was fed into the reactor at a flow rate of 0.03ml/min, and the liquid level in the reactor was maintained at 2/3 of the total height to continue the hydrogenolysis reaction to obtain propylene glycol. After 24h of reaction, a sample was taken from the gas-liquid separator for analysis. The reaction results are shown in Table 1.
Pt-WO 3 /Al 2 O 3 The catalyst has Pt content of 2% and is prepared through conventional soaking process.
TABLE 1 propylene glycol production results from the catalytic conversion of glycerol
Reaction conversion (%) = (moles of reactant converted/moles of reactant in starting material) × 100%.
Product selectivity (%) = (moles of certain product produced/moles of reactant converted) × 100%.
Wherein others comprise acetone, ethylene glycol.
According to the reaction results of the above examples 1 to 6, the hydrogenolysis efficiency of glycerin in the slurry bed reactor was high, and the conversion rate of glycerin was higher than 76%. The main products of the hydrogen flow rate at a lower value (example 1) were secondary hydrogenolysis products such as n-propanol (6.5%) and isopropanol (55.5%). But the generated 1, 2-propylene glycol and 1, 3-propylene glycol can be timely brought out of the reaction system by gradually increasing the hydrogen flow rate, the secondary hydrogenolysis reaction is obviously inhibited, and the total selectivity of the 1, 2-propylene glycol and the 1, 3-propylene glycol can reach 83.5 percent.
In contrast, the reaction of comparative example 1 showed a low hydrogenolysis efficiency of glycerol in the reaction vessel, a conversion of glycerol of only 20.5% at 24 hours, and a low total selectivity (27%) for the main products n-propanol (65%), 1, 2-propanediol and 1, 3-propanediol. According to the reaction results in comparative example 2, the hydrogenolysis efficiency of glycerol in the trickle bed reactor was slightly improved, the glycerol conversion rate was 34.4%, and the 1, 3-propanediol selectivity was also significantly improved to 45.5%, but the 1, 2-propanediol selectivity was still only 5.1% lower.
Comparative examples 1,
Weighing Pt-WO 3 /Al 2 O 3 Catalyst 1.5g (200-300 mesh), 30g of 60wt% glycerol aqueous solution were added to a 50mL autoclave. Setting the reaction temperature at 140 ℃ and the reaction pressure at 5.0MPa, stopping the reaction after reacting for 24 hours, and sampling and analyzing after cooling. The reaction results are shown in Table 1.
Pt-WO 3 /Al 2 O 3 The catalyst is prepared by a conventional impregnation method with the Pt content of 2%.
Comparative examples 2,
Weighing Pt-WO 3 /Al 2 O 3 10.0g (20-40 mesh) of catalyst, and the weighed catalyst was charged in the constant temperature section of the trickle bed reactor. The upper part and the lower part of a catalyst bed layer in the reactor are respectively filled with a certain amount of quartz sand with the same mesh number as the catalyst.
The reaction temperature is set to be 140 ℃, the reaction pressure is 5.0MPa, and the liquid space velocity is 0.1h- 1 Wherein, the hydrogen atmosphere adopts pure hydrogen, and the flow rate is 300mL/min. A60 wt% aqueous solution of glycerin was fed into the reaction tube at a flow rate of 0.028ml/min, reacted for 24 hours, and sampled for analysis. The reaction results are shown in Table 1.
Pt-WO 3 /Al 2 O 3 The Pt content of the catalyst is 3 percent, and the catalyst is prepared by a conventional impregnation method.
Claims (6)
1. A method for preparing propylene glycol by the catalytic hydrogenolysis of glycerol comprises the following steps: 1) Adding a powdered metal hydrogenolysis catalyst and glycerol into a slurry bed reactor;
2) Continuously introducing hydrogen into the slurry bed reactor in the step 1), carrying out hydrogenolysis reaction to generate propylene glycol, and carrying the generated propylene glycol out of the slurry bed reactor by the introduced hydrogen;
in step 2), the hydrogenolysis reaction conditions are as follows: introducing the hydrogen with the flow rate of 100 to 600mL/min;
3) Pumping the glycerol aqueous solution into the slurry bed reactor for carrying out hydrogenolysis reaction in the step 2), and maintaining the liquid level height in the slurry bed reactor to continuously carry out the step 2) to obtain the propylene glycol;
the metal hydrogenolysis catalyst is selected from at least one of a copper-based catalyst, a platinum-based catalyst, and an iridium-rhenium catalyst;
the particle size of the metal hydrogenolysis catalyst is 100-400 meshes;
in the steps 1) and 3), the mass concentration of the glycerol aqueous solution is 50 to 90 percent;
the pumping flow rate of the glycerol aqueous solution is 0.005 to 5 mL/min;
the slurry bed reactor is provided with a gas distributor, hydrogen enters the reactor through the gas distributor to form bubbles with extremely small particle size, the gas-liquid contact area is high, and the mass transfer resistance of the hydrogen is low.
2. The method of claim 1, wherein: the mass ratio of the glycerol to the metal hydrogenolysis catalyst in the step 1) is 5 to 50:1.
3. the method of claim 2, wherein: the mass ratio of the glycerol to the metal hydrogenolysis catalyst in the step 1) is 10 to 40:1.
4. the method according to claim 1 or 2, characterized in that: in the step 2), the pressure is 0.5 to 8.0MPa; the temperature is 110 to 200 ℃.
5. The method of claim 4, wherein: the pressure is 1.0 to 6MPa; the temperature is 120 to 180 ℃.
6. The method according to claim 1 or 2, characterized in that: the height of the liquid level in the slurry bed reactor is maintained at 2/3 to 4/5 of the height of the slurry bed reactor.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202110564794.4A CN113429260B (en) | 2021-05-24 | 2021-05-24 | Method for preparing propylene glycol by catalytic hydrogenolysis of glycerol |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202110564794.4A CN113429260B (en) | 2021-05-24 | 2021-05-24 | Method for preparing propylene glycol by catalytic hydrogenolysis of glycerol |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN113429260A CN113429260A (en) | 2021-09-24 |
| CN113429260B true CN113429260B (en) | 2023-04-07 |
Family
ID=77802713
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202110564794.4A Active CN113429260B (en) | 2021-05-24 | 2021-05-24 | Method for preparing propylene glycol by catalytic hydrogenolysis of glycerol |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN113429260B (en) |
Family Cites Families (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN100432034C (en) * | 2007-02-07 | 2008-11-12 | 南京工业大学 | Method of continuously preparing 1,2-dihydroxypropane by glycerin catalytic hydrogenation |
| CN100537503C (en) * | 2007-05-31 | 2009-09-09 | 上海华谊丙烯酸有限公司 | Process for preparing n-propanol by hydrogenating glycerol |
| CN101085719B (en) * | 2007-06-29 | 2011-09-21 | 上海华谊丙烯酸有限公司 | Method for preparing 1,2-dihydroxypropane by glycerine hydrogenation |
| CN101723801B (en) * | 2008-10-24 | 2013-12-18 | 中国科学院大连化学物理研究所 | Method for preparing 1,3-propylene glycol by directly hydrogenizing glycerol |
| CN102924233B (en) * | 2012-10-20 | 2015-04-15 | 青岛科技大学 | Method for preparing propylene glycol by glycerin hydrogenolysis |
| CN103357427B (en) * | 2013-07-31 | 2015-03-25 | 合肥工业大学 | Nano-metal/solid alkali composite catalyst, preparation method and applications |
| CN104058933A (en) * | 2014-06-23 | 2014-09-24 | 上海康沃生化科技有限公司 | Biodiesel based crude glycerol catalytic hydrogenolysis method for preparation of propylene glycol |
| CN109608307B (en) * | 2017-09-30 | 2022-12-20 | 张家港美景荣化学工业有限公司 | Method for preparing 1, 3-propylene glycol by glycerol hydrogenolysis and reaction system thereof |
| CN108636440B (en) * | 2018-04-16 | 2021-08-10 | 江苏七洲绿色化工股份有限公司 | Catalyst for preparing 1, 3-propylene glycol by hydrogenation of glycerol aqueous solution and preparation method thereof |
| CN111330573A (en) * | 2020-04-10 | 2020-06-26 | 江苏诺盟化工有限公司 | Catalyst for preparing 1, 3-propylene glycol from glycerol and method for preparing 1, 3-propylene glycol by adopting loop reactor |
-
2021
- 2021-05-24 CN CN202110564794.4A patent/CN113429260B/en active Active
Also Published As
| Publication number | Publication date |
|---|---|
| CN113429260A (en) | 2021-09-24 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN106946894B (en) | Application of the Pd radicel duplex metal catalyst in HBIW catalytic hydrogenolytic cleavage | |
| CN106750244B (en) | A method of polyether polyol is prepared using micro passage reaction | |
| CN111514938B (en) | Catalyst for preparing methanol by carbon dioxide hydrogenation and preparation method thereof | |
| CN101502802A (en) | Catalyst for continuous production of succinic anhydride from hydrogenation of maleic anhydride and preparation method thereof | |
| CN105732288B (en) | A kind of selection method of hydrotreating of C-4-fraction | |
| CN104582839A (en) | Catalyst for hydrogenolysis of polyhydric alcohol and method for producing 1,3-propane diol by using the catalyst | |
| CN104707664A (en) | Preparation method of alpha-alumina carrier for silver catalyst | |
| CN108892607B (en) | Preparation method of hydroxycitronellal | |
| CN113429260B (en) | Method for preparing propylene glycol by catalytic hydrogenolysis of glycerol | |
| CN111167515B (en) | Monomolecular heteropoly acid inlaid honeycomb-shaped carbon material loaded nano metal catalyst and preparation method and application thereof | |
| CN104230643A (en) | Preparation method of isopropyl benzene | |
| CN114522738B (en) | Method for preparing 1, 3-propylene glycol by one-step hydrogenation of 3-acetoxy propionaldehyde | |
| CN108602737A (en) | Glycolaldehyde method for hydrogenation | |
| CN101209415B (en) | Catalyst for preparing linalyl acetate by hydrogenation of dehydrogenated linalyl acetate | |
| CN109475844B (en) | Process for the production of glycols from sorbitol | |
| CN112023963B (en) | Catalyst for synthesizing 1, 4-butynediol and application | |
| CN105727972A (en) | Preparation method of catalyst for methane reforming with carbon dioxide to synthetic gas | |
| CN102731253B (en) | Method capable of inhibiting generation of cyclic ether alcohol and used for preparing glycol by catalytic conversion of cellulose | |
| CN102731256B (en) | Method for preparing glycol by conversing cellulose for inhibiting cyclic ether alcohol | |
| CN113788737A (en) | Triple bond partial hydrogenation method and catalyst thereof | |
| CN104759294A (en) | Preparation method and application of copper-based hydrotalcite-like catalyst modified by heteropoly anion | |
| CN104888778B (en) | A kind of Cu/MgO catalyst of catalysis glucose hydrogenolysis and preparation method thereof | |
| CN109806871A (en) | Glycidol adds hydrogen to prepare cobalt-aluminium oxide catalyst of 1,3- propylene glycol and preparation method thereof | |
| CN109796305A (en) | A method of cyclohexanol is prepared using composite catalyst | |
| CN115894196B (en) | Method for continuously synthesizing cyclopentanone |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| CB02 | Change of applicant information | ||
| CB02 | Change of applicant information |
Address after: 101407 No.1, south 2nd Yueyuan street, C District, Yanqi Economic Development Zone, Huairou District, Beijing Applicant after: Zhongke synthetic oil Technology Co.,Ltd. Address before: 101407 No.1, south 2nd Yueyuan street, C District, Yanqi Development Zone, Huairou District, Beijing Applicant before: SYNFUELS CHINA TECHNOLOGY Co.,Ltd. |
|
| GR01 | Patent grant | ||
| GR01 | Patent grant |