Preparation process of high-efficiency and high-purity polyether polyol

Abstract

The invention relates to the technical field of polyether polyol preparation, and discloses a high-efficiency and high-purity polyether polyol preparation process, which comprises the following steps: 1, selecting a KOH catalyst polyether process or a bimetallic catalyst polyether process according to the model of a material; 2, an initiator is fed and heated; s2, feeding of epoxypropane; s3, carrying out internal pressure reaction; s4, removing monomers, cooling and sampling; s5, feeding pure water and phosphoric acid; s6, sampling and adding an auxiliary agent; s7, performing vacuum drying and sampling; the polyether polyol produced by the method comprises two categories, namely a soft foam series and a hard foam series, the soft foam series adopts a DMC process and a 65m < 3 > production line, the hard foam series adopts a KOH process and a 28m < 3 > production line, the production capacity is 160,000 tons per year, the stable product quality is ensured, the production cost of the product is reduced, and the product yields of the polyether polyol produced by the two processes are both greater than 99.5%.

Description

Technical Field

[0001] The invention relates to the technical field of polyether polyol preparation, in particular to a high-efficiency and high-purity polyether polyol preparation process. Background Art

[0002] Polyether polyol (abbreviated as polyether) is an organic polymer, which is obtained by polyaddition reaction of initiator (compound containing active hydrogen group) with ethylene oxide (EO), propylene oxide (PO), butylene oxide (BO) etc. in the presence of catalyst. The polyether with the largest output is produced by using glycerol (propylene glycol) as initiator and epoxide (generally PO and EO are used together). By changing the feeding method of PO and EO (mixed or separate), feeding ratio, feeding order and other conditions, various general-purpose polyether polyols are produced.

[0003] There are many types of existing polyether polyols. It is difficult to achieve the goal of high efficiency and high purity by using only a single preparation process, and the product yield is not ideal. In view of the above problems, it is necessary to improve the existing process. Summary of the invention

[0004] The purpose of the present invention is to provide a high-efficiency and high-purity polyether polyol preparation process to solve the problem that there are many types of existing polyether polyols mentioned in the above background technology, it is difficult to achieve the purpose of high efficiency and high purity by using only a single preparation process, and the product yield is not ideal.

[0005] To achieve the above object, the present invention provides the following technical solution: a high-efficiency and high-purity polyether polyol preparation process, comprising the following steps:

[0006] Step 1: First, choose to use KOH catalyst polyether process or bimetallic catalyst polyether process according to the material model. The soft foam series includes polyether polyols of models such as MN3050D, DL1000D~DL4000D, and the hard foam series includes polyether polyols of models such as MN500, DL400, SU450L.

[0007] Step 2: The process flow of KOH catalyst polyether is as follows:

[0008] S1: Initiator feeding and heating: Initiator and catalyst are added into the reactor in proportion and sequence. After qualified replacement, the low-pressure steam valve of the jacket is opened and the temperature is raised to above the set temperature of 80°C.

[0009] S2: Propylene oxide feeding: After confirming that the propylene oxide feeding conditions are met, add the specified amount of propylene oxide into the reactor according to the feeding curve. During the propylene oxide feeding process, the internal temperature, internal pressure and liquid level changes must be monitored.

[0010] S3: Internal pressure reaction: After the propylene oxide feeding is completed, the internal pressure reaction is maintained for a certain period of time to ensure that the propylene oxide reaction is complete.

[0011] S4: Demonomerization and cooling sampling: Maintain the temperature in the kettle, turn on the vacuum pump to perform demonomerization, remove unreacted propylene oxide, etc., pass cooling water into the inner coil of the reactor to reduce the temperature in the reactor to below 90°C, and perform sampling and testing. After the sampling is qualified, use nitrogen to press the materials in the reactor to the drying kettle.

[0012] S5: Pure water and phosphoric acid feeding: After the reaction kettle is pipetted, add the specified amount of pure water and phosphoric acid into the drying kettle.

[0013] S6: Sampling and adding additives: Turn on the stirring, stir thoroughly for a certain period of time, then take a sample to measure the pH value. After the pH value is qualified, add a specified amount of additives, pass low-pressure steam into the drying kettle jacket, and raise the temperature of the drying kettle to the specified value.

[0014] S7: Vacuum drying and sampling: Start the vacuum pump, increase the temperature and dry according to the specified drying curve, and take samples on site to measure the moisture and pH value in the drying kettle.

[0015] S8: Filtration cycle: After the moisture content is qualified, it is filtered through the filter. After the filtration is completed, a quantitative antioxidant is added and the product is pumped into the finished product tank.

[0016] The process flow of bimetallic catalyst polyether is as follows:

[0017] S1: Initiator / catalyst feeding: add quantitative initiator and catalyst into the reactor; replace with nitrogen and heat up after passing the gas replacement.

[0018] S2: Propylene oxide feeding: After confirming that the propylene oxide feeding conditions are met, add the specified amount of propylene oxide into the reactor according to the feeding curve. During the propylene oxide feeding process, the internal temperature, internal pressure and liquid level changes must be monitored.

[0019] S3: Internal pressure reaction: After the propylene oxide feeding is completed, the internal pressure reaction is maintained for a certain period of time to ensure that the propylene oxide reaction is complete.

[0020] S4: Demonomerization: Maintain the temperature in the kettle and start the vacuum pump to carry out demonomerization to remove unreacted propylene oxide, etc.

[0021] S5: Cooling sampling: Cooling water is passed into the inner coil of the reactor to reduce the temperature inside the reactor to below 90°C, and sampling is performed for testing. After the sampling is qualified, a quantitative antioxidant is added, and the material in the reactor is pressurized into the product storage tank with nitrogen.

[0022] Compared with the prior art, the present invention has the following beneficial effects:

[0023] 1. The high-efficiency and high-purity polyether polyol preparation process can achieve the purpose of high yield. The polyether polyol produced by the present invention includes two categories, namely, soft foam series and hard foam series. The soft foam series adopts DMC process and 65m3 production line, and the hard foam series adopts KOH process and 28m 3 The production line has a total annual production capacity of 160,000 tons. While ensuring stable product quality, it reduces the production cost of products. The soft foam series includes polyether polyols of models such as MN3050D, DL1000D~DL4000D, and the hard foam series includes polyether polyols of models such as MN500, DL400, SU450L. The product yields of polyether polyols from both processes are greater than 99.5%.

[0024] 2. DMC is the abbreviation of bimetallic catalyst. Its advantages over KOH catalyst are high catalytic activity, short reaction time, high product conversion rate, uniform molecular weight distribution and high product quality stability. If DMC catalyst is used, there is no vacuum drying and filtration cycle step, because the purpose of vacuum drying and filtration cycle is to remove potassium ions. When DMC is used as a catalyst, there is no potassium ions, so there is no need for drying and filtration. All brands of products can use KOH, but some brands cannot use DMC. The process flow of using DMC catalyst is short and saves investment. There are two production processes for polyether production, KOH catalyst and DMC catalyst. Both have their own advantages and disadvantages. The two production processes are indispensable. The production process of the process is basically the same, but the formulation system is different. DETAILED DESCRIPTION

[0025] The following will be combined with the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technical personnel in this field without making creative work are within the scope of protection of the present invention.

[0026] The present invention provides a technical solution: a high-efficiency and high-purity polyether polyol preparation process, comprising the following steps:

[0027] Step 1: First, choose to use KOH catalyst polyether (hard foam) process or bimetallic catalyst polyether (soft foam) process according to the material model. The soft foam series includes polyether polyols of models such as MN3050D, DL1000D~DL4000D, and the hard foam series includes polyether polyols of models such as MN500, DL400, SU450L.

[0028] Example 1

[0029] The process flow of KOH catalyst polyether (rigid foam) is as follows:

[0030] S1: Initiator feeding and heating: Initiator (glycerol, ethylene glycol, etc.) and catalyst are added to the reactor in proportion and order. After the replacement is qualified, the low-pressure steam valve of the jacket is opened and the temperature is raised to above the set temperature of 80°C.

[0031] S2: Propylene oxide (or ethylene oxide) feeding: After confirming that the propylene oxide (or ethylene oxide) feeding conditions are met, add a specified amount of propylene oxide (or ethylene oxide) into the reactor according to the feeding curve. During the propylene oxide (or ethylene oxide) feeding process, monitor the changes in internal temperature, internal pressure and liquid level.

[0032] S3: Internal pressure reaction: After the feeding of propylene oxide (or ethylene oxide) is completed, the internal pressure reaction is maintained for a certain period of time to ensure that the propylene oxide (or ethylene oxide) reacts completely.

[0033] S4: Demonomerization and cooling sampling: Maintain the temperature in the kettle, turn on the vacuum pump to perform demonomerization, remove unreacted propylene oxide, etc., pass cooling water into the inner coil of the reactor to reduce the temperature in the reactor to below 90°C, and perform sampling and testing. After the sampling is qualified, use nitrogen to press the materials in the reactor to the drying kettle.

[0034] S5: Pure water and phosphoric acid feeding: After the reaction kettle is pipetted, add the specified amount of pure water and phosphoric acid into the drying kettle.

[0035] S6: Sampling and adding additives: Turn on the stirring, stir thoroughly for a certain period of time, then take a sample to measure the pH value. After the pH value is qualified, add a specified amount of additives, pass low-pressure steam into the drying kettle jacket, and raise the temperature of the drying kettle to the specified value.

[0036] S7: Vacuum drying and sampling: Start the vacuum pump, increase the temperature and dry according to the specified drying curve, and take samples on site to measure the moisture and pH value in the drying kettle.

[0037] S8: Filtration cycle: After the moisture content is qualified, it is filtered through the filter. After the filtration is completed, a quantitative antioxidant is added and the product is pumped into the finished product tank.

[0038] Example 2

[0039] The process flow of bimetallic catalyst polyether (soft foam) is as follows:

[0040] S1: Initiator / catalyst feeding: add quantitative initiator (glycerol, ethylene glycol, etc.) and catalyst into the reactor; replace with nitrogen and heat up after passing the process.

[0041] S2: Propylene oxide (or ethylene oxide) feeding: After confirming that the propylene oxide (or ethylene oxide) feeding conditions are met, add a specified amount of propylene oxide (or ethylene oxide) into the reactor according to the feeding curve. During the propylene oxide (or ethylene oxide) feeding process, monitor the changes in internal temperature, internal pressure and liquid level.

[0042] S3: Internal pressure reaction: After the feeding of propylene oxide (or ethylene oxide) is completed, the internal pressure reaction is maintained for a certain period of time to ensure that the propylene oxide (or ethylene oxide) reacts completely.

[0043] S4: Demonomerization: Maintain the temperature in the kettle and start the vacuum pump to carry out demonomerization to remove unreacted propylene oxide (or ethylene oxide) and the like.

[0044] S5: Cooling sampling: Cooling water is passed into the inner coil of the reactor to reduce the temperature inside the reactor to below 90°C, and sampling is performed for testing. After the sampling is qualified, a quantitative antioxidant is added, and the material in the reactor is pressurized into the product storage tank with nitrogen.

[0045] It should be noted that:

[0046] (1) DMC is the abbreviation of bimetallic catalyst. Its advantages over KOH catalyst are high catalytic activity, short reaction time, high product conversion rate, uniform molecular weight distribution, and high product quality stability.

[0047] (2) If DMC catalyst is used, there is no vacuum drying and filtration cycle step, because the purpose of the vacuum drying and filtration cycle is to remove potassium ions. When DMC is used as a catalyst, potassium ions do not exist, so drying and filtration are not required.

[0048] (3) All brands of products can use KOH, but some brands cannot use DMC. Using DMC catalyst shortens the process flow and saves investment.

[0049] (4) There are two production processes for polyether production: KOH catalyst and DMC catalyst. Both have their own advantages and disadvantages. The two production processes are indispensable. The production processes are basically the same, but the formulation systems are different.

[0050] The above shows and describes the basic principles, main features and advantages of the present invention. Technical personnel in this industry should understand that the present invention is not limited to the above embodiments. The above embodiments and descriptions are only preferred examples of the present invention and are not used to limit the present invention. Without departing from the spirit and scope of the present invention, the present invention may have various changes and improvements, which fall within the scope of the present invention to be protected. The scope of protection of the present invention is defined by the attached claims and their equivalents.

[0051] The directions or positional relationships indicated by terms such as "center", "longitudinal", "lateral", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside" and "outside" are based on the directions or positional relationships shown and are merely simplified descriptions for the convenience of describing the present invention. They do not indicate or imply that the devices or elements referred to must have a specific direction, be constructed and operated in a specific direction, and therefore should not be understood as limiting the protection content of the present invention.

[0052] Although the present invention has been described in detail with reference to the aforementioned embodiments, it is still possible for those skilled in the art to modify the technical solutions described in the aforementioned embodiments, or to make equivalent substitutions for some of the technical features therein. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A high-efficiency and high-purity polyether polyol preparation process, characterized in that: The following steps are involved: Step 1: First, choose to use KOH catalyst polyether process or bimetallic catalyst polyether process according to the material model. The soft foam series includes polyether polyols of MN3050D, DL1000D~DL4000D, and the hard foam series includes polyether polyols of MN500, DL400, SU450L, etc.; Step 2: The process flow of KOH catalyst polyether is as follows: S1: Initiator feeding and heating: Initiator and catalyst are added to the reactor in proportion and order. After the replacement is qualified, the low-pressure steam valve of the jacket is opened and the temperature is raised to above the set temperature of 80°C; S2: Propylene oxide feeding: After confirming that the propylene oxide feeding conditions are met, add the specified amount of propylene oxide into the reactor according to the feeding curve. During the propylene oxide feeding process, the internal temperature, internal pressure and liquid level changes must be monitored; S3: Internal pressure reaction: After the propylene oxide is fed, the internal pressure reaction is maintained for a certain period of time to ensure that the propylene oxide reaction is complete; S4: De-monomerization and cooling sampling: Maintain the temperature in the kettle, turn on the vacuum pump to de-monomerize, remove the unreacted propylene oxide, etc., pass cooling water into the inner coil of the reactor to reduce the temperature in the reactor to below 90°C, and perform sampling and testing. After the sampling is qualified, use nitrogen to press the materials in the reactor into the drying kettle; S5: pure water and phosphoric acid feeding: after the reaction kettle is pipetted, a specified amount of pure water and phosphoric acid are added into the drying kettle; S6: Sampling and adding additives: Start stirring, stir thoroughly for a certain period of time, take samples to measure the pH value, and after the pH value is qualified, add a specified amount of additives, pass low-pressure steam into the drying kettle jacket, and raise the temperature of the drying kettle to the specified value; S7: Vacuum drying and sampling: Start the vacuum pump, heat and dry according to the specified drying curve, and take samples on site to measure the moisture and pH value in the drying kettle; S8: Filtration cycle: After the moisture content is qualified, it is filtered through the filter. After the filtration is completed, a quantitative antioxidant is added and the product is pumped into the finished product tank; The process flow of bimetallic catalyst polyether is as follows: S1: Initiator / catalyst feeding: add quantitative initiator and catalyst into the reactor; replace with nitrogen and heat up after passing the gas; S2: Propylene oxide feeding: After confirming that the propylene oxide feeding conditions are met, add the specified amount of propylene oxide into the reactor according to the feeding curve. During the propylene oxide feeding process, the internal temperature, internal pressure and liquid level changes must be monitored; S3: Internal pressure reaction: After the propylene oxide is fed, the internal pressure reaction is maintained for a certain period of time to ensure that the propylene oxide reaction is complete; S4: Demonomerization: Maintain the temperature in the kettle, turn on the vacuum pump to carry out demonomerization, and remove the unreacted propylene oxide, etc.; S5: Cooling sampling: Cooling water is passed into the inner coil of the reactor to reduce the temperature inside the reactor to below 90°C, and sampling is performed for testing. After the sampling is qualified, a quantitative antioxidant is added, and the material in the reactor is pressurized into the product storage tank with nitrogen.