Method for treating alcohol ester by-product in production of preparing ethylene glycol from synthesis gas

Abstract

The invention provides a continuous treatment production system for an alcohol ester byproduct in production of preparing ethylene glycol from synthesis gas. The invention also provides a treatment experiment system for the alcohol ester by-product in the production of preparing ethylene glycol from synthesis gas. The invention further provides a treatment production method for the alcohol ester byproduct in the production of preparing ethylene glycol from synthesis gas. The invention further provides a treatment experiment method for the alcohol ester by-product in the production of preparing ethylene glycol from synthesis gas. The invention further provides a formate and a use thereof. According to the treatment method for the alcohol ester byproduct in the production of preparing ethylene glycol from synthesis gas, provided by the invention, the methyl formate-containing byproduct does not need to be separated into pure components, so that dimethyl carbonate can be recycled to the greatest extent, and the difficulty of purifying formate is greatly reduced.

Description

Technical Field

[0001] This invention belongs to the technical field of syngas-to-ethylene glycol production, and relates to a method for treating alcohol ester byproducts in syngas-to-ethylene glycol production, specifically a method for treating methyl formate, an alcohol ester byproduct in syngas-to-ethylene glycol production, to convert it into formate salt. Background Technology

[0002] In existing industrial technologies, the syngas-to-ethylene glycol process commonly uses nitric oxide, oxygen, and methanol (ME) to produce methyl nitrite. Methyl nitrite (MN) then reacts with carbon monoxide to produce the intermediate dimethyl oxalate (DMO), which is subsequently hydrogenated to obtain ethylene glycol (EG). However, the synthesis of methyl nitrite and dimethyl oxalate also generates byproducts such as methyl formate (MF), dimethyl carbonate (DMC), and methyl acetal (ML). Methyl formate has a low boiling point, making it unsuitable for storage and transportation. Some companies have proposed converting methyl formate into formate salts for utilization.

[0003] In patent CN113248363A disclosed by Yueyang Changde Environmental Technology Co., Ltd., methyl formate waste liquid is first hydrolyzed with sulfuric acid solution, and then reacted with calcium hydroxide (Ca(OH)2) at a temperature of 10℃ to 50℃ for 4-12 hours to obtain calcium formate (CaF). Although this process utilizes methyl formate, it requires sulfuric acid for hydrolysis, which makes the equipment highly susceptible to corrosion and increases operating costs.

[0004] In patent CN113651686A of China Salt Anhui Hongsifang Co., Ltd., a multi-tower, stepwise separation method is used to process methyl formate waste liquid. MN, ME, ML, and MF are gradually separated and purified to obtain approximately 99% MF, which is then reacted with sodium hydroxide (NaOH) solution for saponification to produce sodium formate (NaF). Furthermore, the recovered ML and ME also achieve a purity of approximately 99%. This process requires four towers: an MN removal tower, an MF purification tower, an MF recovery tower, and an ME recovery tower. The process is complex, with high equipment investment and energy consumption. In reality, ML can form an azeotrope with ME and H2O, making it difficult to obtain relatively pure ML through conventional distillation. Additionally, since the reaction between MF and alkali solution is readily occurring, it is unnecessary to purify MF to approximately 99%. ME is returned to the ethylene glycol main unit for reuse, and an acceptable level for ME purity can be found where it is not critical.

[0005] In summary, it may be uneconomical to recycle this alcohol ester byproduct with a flow rate of only about 1.5 t / h using a complex process. Xinjiang Zhichuang New Materials Co., Ltd. disclosed a process for treating MF-containing waste liquid in patent CN115636746A. This process does not require prior separation of MN gas; it directly mixes the MF waste liquid with calcium-containing inorganic matter and water under near-room temperature and atmospheric pressure conditions, resulting in an exothermic reaction. The gas phase obtains MN, which is recycled back to the carbonyl chemical section. The solid phase is high-value-added crude CaF, and the liquid phase is a saturated aqueous solution of CaF containing ML and ME. After simple distillation, ML and ME solutions are obtained, and the saturated aqueous solution of CaF in the bottom of the column is recycled. However, since the actual reactant Ca(OH)2 is only slightly soluble in water, with a solubility of only 1.65 g / L at 20°C, and even lower in the presence of organic matter; and since the embodiment uses solid calcium oxide (CaO), the reaction system must contain a large amount of solid matter, preventing the reaction from being homogeneous; moreover, the process includes a filtration unit, making it complex and intermittently operated. The aforementioned factors result in low reaction efficiency, high requirements for stirring and conveying equipment, and an inability to operate continuously and stably. Typically, the byproduct alcohol ester contains DMC, a valuable chemical that should be recovered as much as possible. However, DMC can react with alkali to form carbonates, leading to DMC loss. The patent does not specify how to minimize DMC reaction while MF reacts with alkali. Summary of the Invention

[0006] In view of the characteristics of the prior art described above, the purpose of this invention is to provide a simple process for treating alcohol ester byproducts in the production of ethylene glycol from syngas.

[0007] To achieve the above and other related objectives, the first aspect of the present invention provides a continuous processing production system for alcohol ester byproducts in the production of ethylene glycol from syngas. Along the input direction of the alcohol ester byproduct stream containing methyl formate from the syngas-to-ethylene glycol process, a stirred tank reactor and a light component recovery tower are sequentially connected. The stirred tank reactor is connected to an alcohol ester byproduct stream pipeline and an alkali input pipeline. The rectification section of the light component recovery tower is sequentially connected from top to bottom to a first side-line outlet pipeline and a second side-line outlet pipeline. A condenser and a reflux tank are sequentially connected along the liquid phase stream output direction outside the top of the light component recovery tower. The condenser and reflux tank are connected to the top of the light component recovery tower to form a loop. The condenser is also connected to a non-condensable gas outlet pipeline at the top of the tower, and the reflux tank is also connected to a liquid phase outlet pipeline at the top of the tower. A reboiler is provided at the bottom of the light component recovery tower, and the reboiler is connected to the bottom of the light component recovery tower to form a loop. The bottom of the light component recovery tower is also connected to a bottom outlet pipeline.

[0008] The second aspect of the present invention provides an experimental system for treating alcohol ester byproducts in the production of ethylene glycol from syngas, comprising an oil bath, a flask, a metering pump, and a pH meter. The flask is placed inside the oil bath and connected to the metering pump via a pipeline. The metering pump is also externally connected to an alkali tank. The flask is also connected to a condenser tube, and the pH meter is inserted into the flask.

[0009] The third aspect of this invention provides a method for processing alcohol ester byproducts in the production of ethylene glycol from syngas, comprising: directly mixing and reacting an alcohol ester byproduct stream containing methyl formate (MF) from the syngas-to-ethylene glycol process with an alkaline solution without separation and purification; distilling the resulting reaction solution to collect non-condensable gas stream, MN and MF liquid stream, ML and ME liquid stream, ME and DMC liquid stream, and formate aqueous solution liquid stream; recovering DMC through the ME and DMC liquid stream; and recovering formate through the formate aqueous solution liquid stream.

[0010] The fourth aspect of the present invention provides an experimental method for treating alcohol ester byproducts in the production of ethylene glycol from syngas, using the above-mentioned experimental system for treating alcohol ester byproducts in the production of ethylene glycol from syngas, comprising: adding MF to a flask and then placing it in an oil bath for stirring and heating; then taking alkali solution from an alkali solution tank and inputting it into the flask for mixing and reaction; then removing the flask and cooling it to obtain a reaction solution.

[0011] The fifth aspect of the present invention provides a formate, which is obtained by the above-mentioned production method for treating alcohol ester by-products in the production of ethylene glycol from syngas or by the experimental method for treating alcohol ester by-products in the production of ethylene glycol from syngas.

[0012] The sixth aspect of the present invention provides the use of formate in oil fields, in the production of potassium diformate, or as a hydrogen storage and production carrier.

[0013] As described above, the method for treating alcohol ester byproducts in the production of ethylene glycol from syngas provided by the present invention has the following beneficial effects:

[0014] (1) The present invention provides a method for treating alcohol ester by-products in the production of ethylene glycol from syngas, which does not require separating the methyl formate by-products in the syngas-to-ethylene glycol process system into pure components, and the process is simple.

[0015] (2) The present invention provides a method for treating alcohol ester byproducts in the production of ethylene glycol from syngas. Under preferred reaction conditions, methyl formate reacts with alkali while a very small amount of dimethyl carbonate reacts with alkali. This allows for the maximum recovery of dimethyl carbonate and significantly reduces the difficulty of purifying formate.

[0016] (3) The present invention provides a method for treating alcohol ester byproducts in the production of ethylene glycol from syngas. Because the alkali has high solubility, for example, 100g of water can dissolve 126g of potassium hydroxide at 30℃. The potassium formate produced by the alkali and methyl formate also has high solubility. Only a small amount of water needs to be introduced to keep the entire process in solution, which greatly facilitates continuous chemical production.

[0017] (4) The present invention provides a method for treating alcohol ester byproducts in the production of ethylene glycol from syngas. Formate can be sold in the form of an aqueous solution without further drying into a solid product, thus saving energy consumption.

[0018] (5) The present invention provides a method for treating alcohol ester byproducts in the production of ethylene glycol from syngas. The potassium formate obtained by the present invention has high value and is environmentally friendly. It is mainly used in the oilfield industry, and can also be used as a snow melting agent, soil conditioner, and raw material for the production of potassium diformate. In addition, it can be used as a potential hydrogen storage and hydrogen production carrier. Attached Figure Description

[0019] Figure 1 The diagram shows a structural diagram of a production system for processing alcohol ester byproducts in the production of ethylene glycol from syngas according to the present invention. In this diagram, a is a stirred tank reactor; b is a discharge pump; c is a condenser; d is a reflux tank; e is a reflux pump; f is a reboiler; g is a light component recovery tower; h is a bottom pump; A is an alcohol ester byproduct stream pipeline; B is an alkali input pipeline; C is a non-condensable gas output pipeline at the top of the tower; D is a liquid phase collection pipeline at the top of the tower; E is a first side stream collection pipeline; F is a second side stream collection pipeline; G is a bottom collection pipeline; H is a first connecting pipeline; I1 is a first rectification section; I2 is a second rectification section; I3 is a third rectification section; and J is a second connecting pipeline.

[0020] Figure 2 The diagram shows the structure of an experimental system for treating alcohol ester byproducts in the production of ethylene glycol from syngas according to the present invention. In the diagram, 1 is a flask; 2 is an oil bath; 3 is a condenser; 4 is a pH meter; 5 is a metering pump; and 6 is an alkali tank. Detailed Implementation

[0021] The following detailed description discloses an embodiment of a method for treating alcohol ester byproducts in the production of ethylene glycol from syngas, as described in this application. However, unnecessary detailed descriptions may be omitted. For example, detailed descriptions of well-known matters and repetitive descriptions of practically identical structures may be omitted. This is to avoid making the following description unnecessarily lengthy and to facilitate understanding by those skilled in the art. Furthermore, the following description is provided to enable those skilled in the art to fully understand this application and is not intended to limit the subject matter of the claims.

[0022] The "range" disclosed in this application is defined by a lower limit and an upper limit. A given range is defined by selecting a lower limit and an upper limit, which define the boundaries of the particular range. The range defined in this way can include or exclude endpoints and can be arbitrarily combined; that is, any lower limit can be combined with any upper limit to form a range.

[0023] Unless otherwise specified, all embodiments and optional embodiments of this application can be combined to form new technical solutions.

[0024] Unless otherwise specified, all technical features and optional technical features of this application may be combined to form new technical solutions.

[0025] Unless otherwise specified, the terms "comprising" and "including" as used in this application can be open-ended or closed-ended. For example, "comprising" and "including" can mean that other components not listed may also be included, or that only the listed components may be included.

[0026] Unless otherwise specified, the term "or" is inclusive in this application. For example, the phrase "A or B" means "A, B, or both A and B". More specifically, the condition "A or B" is satisfied by any of the following conditions: A is true (or exists) and B is false (or does not exist); A is false (or does not exist) and B is true (or exists); or both A and B are true (or exist).

[0027] The first aspect of this invention provides a continuous processing system for alcohol ester byproducts in the production of ethylene glycol from syngas, such as... Figure 1 As shown, a stirred tank reactor and a light component recovery tower are sequentially connected along the input direction of the alcohol ester byproduct stream containing methyl formate produced from the syngas to ethylene glycol process. The stirred tank reactor is connected to an alcohol ester byproduct stream pipeline and an alkali input pipeline. The rectification section of the light component recovery tower is sequentially connected from top to bottom to a first side-line outlet pipeline and a second side-line outlet pipeline. A condenser and a reflux tank are sequentially connected along the liquid phase stream output direction at the top of the light component recovery tower. The condenser and reflux tank are connected to the top of the light component recovery tower to form a loop. The condenser is also connected to a non-condensable gas outlet pipeline at the top of the tower, and the reflux tank is also connected to a liquid phase outlet pipeline at the top of the tower. A reboiler is provided at the bottom of the light component recovery tower, and the reboiler is connected to the bottom of the light component recovery tower to form a loop. The bottom of the light component recovery tower is also connected to a bottom outlet pipeline.

[0028] In the above production system, the stirred tank reactor is a conventionally used reactor with a stirred tank.

[0029] In the aforementioned production system, such as Figure 1As shown, the stirred tank reactor and the light component recovery tower are connected by a first connecting pipeline, and a discharge pump is provided on the first connecting pipeline.

[0030] In one implementation, such as Figure 1 As shown, one end of the first connecting pipe is connected to the bottom of the stirred tank reactor, and the other end of the first connecting pipe is connected to the rectification section of the light component recovery tower.

[0031] In the aforementioned production system, such as Figure 1 As shown, the alcohol ester byproduct stream pipeline and the alkali inlet pipeline are both connected to the top of the stirred tank reactor. These are used to input the alcohol ester byproduct stream containing methyl formate and the alkali solution.

[0032] In the aforementioned production system, such as Figure 1 As shown, the light component recovery tower is a conventionally used distillation tower.

[0033] In the aforementioned production system, such as Figure 1 As shown, the rectification section in the light component recovery tower has at least three rectification zones arranged from top to bottom, with an interval maintained between adjacent rectification zones.

[0034] In one implementation, such as Figure 1 As shown, the distillation section includes, from top to bottom, a first distillation section, a second distillation section, and a third distillation section. The second distillation section is spaced apart from the first distillation section and the third distillation section, respectively. A first side-line extraction pipeline connects the first distillation section and the second distillation section, and a second side-line extraction pipeline connects the second distillation section and the third distillation section.

[0035] The aforementioned first side-stream extraction pipeline is primarily used to extract the azeotrope of ML and ME, and may also contain small amounts of MN, DMC, and MF. This azeotrope is then sent to the heating furnace of the utility plant for combustion and denitrification before being discharged. The aforementioned second side-stream extraction pipeline is primarily used to extract the azeotrope of ME and DMC, and may also contain small amounts of MN, MF, ML, and H2O. This azeotrope is then sent to the methanol dehydration tower of the syngas-to-ethylene glycol main unit for reuse.

[0036] In a preferred embodiment, such as Figure 1 As shown, a first connecting pipeline is connected below the third distillation section.

[0037] In a preferred embodiment, the first distillation section, the second distillation section, and the third distillation section are provided with trays or packing.

[0038] In a further preferred embodiment, the tray is a sieve tray or a floating valve tray, preferably a floating valve tray.

[0039] In a further preferred embodiment, the packing material is random packing or structured packing, preferably structured packing.

[0040] In a further preferred embodiment, when the first distillation section, the second distillation section, and the third distillation section are provided with trays, each distillation section is provided with 9-11 theoretical trays, preferably 10.

[0041] In the aforementioned production system, such as Figure 1 As shown, the condenser, reflux tank, and the top of the light component recovery tower are connected by a second connecting pipeline to form a loop. A reflux pump is installed on the second connecting pipeline between the reflux tank and the light component recovery tower. The second connecting pipeline is also connected to the liquid phase extraction pipeline at the top of the tower.

[0042] In one implementation, such as Figure 1 As shown, the liquid phase extraction pipeline at the top of the tower is connected to the second connecting pipeline between the reflux pump and the top of the light component recovery tower.

[0043] The aforementioned non-condensable gas output pipeline at the top of the tower is used to output non-condensable gas, primarily N2. The aforementioned liquid phase output pipeline at the top of the tower is used to primarily extract MN and MF, and possibly a small amount of ML, which is then sent to the esterification tower of the syngas to ethylene glycol main unit for reuse.

[0044] The condenser described above is a conventionally used condenser. The reflux tank described above is a conventionally used reflux tank.

[0045] In the aforementioned production system, such as Figure 1 As shown, a bottom pump is installed on the bottom outlet pipeline of the tower.

[0046] The above-mentioned bottom outlet pipeline is used to mainly extract the aqueous solution of formate. The aqueous solution of formate can be further dried in the evaporator to obtain solid formate.

[0047] The reboiler mentioned above is a conventionally used reboiler.

[0048] The aforementioned discharge pump, reflux pump, and bottom pump are all conventionally used material conveying pumps.

[0049] A second aspect of this invention provides an experimental system for treating alcohol ester byproducts in the production of ethylene glycol from syngas, such as... Figure 2 As shown, the device includes an oil bath, a flask, a metering pump, and a pH meter. The flask is placed inside the oil bath and connected to the metering pump via a pipeline. The metering pump is also connected to an external alkali tank. The flask is also connected to a condenser tube, and the pH meter is inserted into the flask.

[0050] In the above experimental system, the oil bath, metering pump, pH meter, alkali tank, and condenser are all conventionally used experimental equipment.

[0051] In the above experimental system, the flask is a conventionally used glass flask.

[0052] The third aspect of this invention provides a method for processing alcohol ester byproducts in the production of ethylene glycol from syngas, comprising: directly mixing and reacting an alcohol ester byproduct stream containing methyl formate (MF) from the syngas-to-ethylene glycol process with an alkaline solution without separation and purification; distilling the resulting reaction solution to collect non-condensable gas stream, MN and MF liquid stream, ML and ME liquid stream, ME and DMC liquid stream, and formate aqueous solution liquid stream; recovering DMC through the ME and DMC liquid stream; and recovering formate through the formate aqueous solution liquid stream.

[0053] In the above method, the syngas-to-ethylene glycol process is a conventional syngas-to-ethylene glycol process, which uses nitric oxide, oxygen and methanol (ME) to react to generate methyl nitrite, then methyl nitrite (MN) reacts with carbon monoxide to generate the intermediate product dimethyl oxalate (DMO), and then hydrogenates to obtain ethylene glycol (EG) product.

[0054] In the above method, the processing method employs the continuous processing production system for alcohol ester byproducts in the production of ethylene glycol from syngas, and includes the following steps:

[0055] 1) The alcohol ester byproduct stream containing methyl formate from the syngas to ethylene glycol process is directly fed into a stirred tank reactor with alkaline solution without separation and purification to obtain a reaction solution. The methyl formate (MF) in the reaction solution reacts with the alkali in the alkaline solution to obtain formate salt. The reaction solution also includes dimethyl carbonate (DMC), methyl acetal (ML), methanol (ME), methyl nitrite (MN), water and unreacted methyl formate (MF).

[0056] 2) The reaction liquid is fed into the light component recovery tower for distillation. Non-condensable gas stream and MN and MF liquid stream are collected from the top of the light component recovery tower. ML and ME liquid streams are collected from the rectification section of the light component recovery tower via the first side line collection pipeline, and ME and DMC liquid streams are collected via the second side line collection pipeline. Formate aqueous solution liquid stream is collected from the bottom of the light component recovery tower. DMC is then recovered through the ME and DMC liquid streams, and formate is recovered through the formate aqueous solution liquid stream.

[0057] In step 1), the alcohol ester byproduct stream containing methyl formate includes not only methyl formate (MF), but also other byproducts such as dimethyl carbonate (DMC), methyl acetal (ML), methanol (ME), and water.

[0058] In step 1), the alcohol ester byproduct stream is decomposed before being mixed with the alkaline solution to remove the heavy components.

[0059] In one embodiment, the alcohol ester byproduct stream is the stream output from the top of the light-weight component removal tower after being treated by removing heavy components in the light-weight component removal tower.

[0060] In step 1), the alcohol ester byproduct stream is free of metal ions and solid particles, and is clear and transparent.

[0061] In step 1), the alcohol ester byproduct stream is fed into the stirred tank reactor via the alcohol ester byproduct stream pipeline.

[0062] In step 1), the flow rate of the alcohol ester byproduct stream fed into the stirred tank reactor is 0.1-20 t / h, specifically 0.1-0.4 t / h, 0.4-17 t / h, 17-20 t / h, and preferably 0.5-16 t / h.

[0063] In step 1), the mass ratio of the alcohol ester byproduct stream to the added alkali solution is 1:0.1-5, specifically 1:0.1-1, 1:1-3, or 1:3-5.

[0064] In step 1), the alkali in the alkaline solution is selected from at least one of potassium hydroxide (KOH), sodium hydroxide (NaOH), and calcium hydroxide (Ca(OH)2), preferably potassium hydroxide (KOH).

[0065] In step 1), the alkaline solution is an aqueous solution of alkali, and the concentration of alkali in the alkaline solution is 25-50 wt%, specifically 25-30 wt%, 30-45 wt%, or 45-50 wt%, preferably 30-45 wt%.

[0066] In step 1), the alkaline solution is fed into the stirred tank reactor via an alkaline solution input pipeline.

[0067] In step 1), the reaction temperature is 50-100℃, specifically 50-60℃, 60-75℃, 75-100℃, preferably 60-85℃.

[0068] In step 1), the reaction pressure is 0-2 MPaG, specifically 0-1 MPaG, 1-2 MPaG, preferably 0.1-0.8 MPaG.

[0069] In step 1), the pH of the reaction is 4-10. The reaction of MF with the base is minimized while the reaction of DMC with the base is minimized.

[0070] In one embodiment, when the concentration of DMC in the alcohol ester byproduct stream is ≤1 wt%, the pH of the reaction is 7-8; when the concentration of DMC in the alcohol ester byproduct stream is >1 wt%, the pH of the reaction is ≥6 and <7. The higher the pH, the higher the conversion rate of DMC, and the greater the corresponding loss of DMC. Therefore, to reduce the conversion rate of DMC, the pH needs to be controlled at a lower level, the disadvantage of which is that the conversion rate of MF will also decrease. Therefore, when the concentration of DMC is already at a low level, such as ≤1 wt%, the pH of the reaction can be controlled at a higher level, such as pH 7-8, so that even if the conversion rate of DMC increases, the amount of DMC converted remains low.

[0071] In step 1), the alcohol ester byproduct stream is directly fed into the stirred tank reactor without separation or purification. The alkali solution is also fed into the stirred tank reactor. This method controls the pH value within a certain range, ensuring that most of the MF reacts with the alkali to be converted into formate, while a very small portion of DMC reacts with the alkali and is mostly recovered, maximizing the economic efficiency of the alcohol ester byproduct. The liquid after the reaction contains MN, MF, ML, ME, DMC, H2O, formate, and carbonate, and is fed from the stirred tank reactor into a light component recovery tower.

[0072] In step 2), the reaction liquid is fed into the light component recovery tower through the first connecting pipeline under the action of the discharge pump.

[0073] In step 2), the operating conditions of the light component recovery tower are: pressure 0-1 MPa; reflux ratio 1-30; tower top temperature 10-60℃; tower bottom temperature 100-180℃.

[0074] In step 2), the non-condensable gas stream is sequentially drawn out from the non-condensable gas output pipeline at the top of the tower via a condenser. The non-condensable gas stream consists of a small amount of non-condensable gas, primarily N2.

[0075] In step 2), the MN and MF liquid phase streams are sequentially drawn from the top liquid phase collection pipeline of the tower through the condenser and reflux tank under the action of the reflux pump. The MN and MF liquid phase streams mainly consist of MN and MF, and may also contain a small amount of ML, which are then sent to the esterification tower of the syngas to ethylene glycol main unit for reuse.

[0076] The aforementioned condenser is used to cool the top of the light component recovery tower.

[0077] In step 2), the ML and ME liquid phase streams are mainly azeotropes of ML and ME, and may also contain small amounts of MN, DMC, and MF. They are sent as fuel to the heating furnace of the public works for combustion and denitrification and emission.

[0078] In step 2), the ME and DMC liquid stream mainly consists of an azeotrope of ME and DMC, possibly with small amounts of MN, MF, ML, and H2O. This is then sent to the methanol dehydration tower of the syngas-to-ethylene glycol main unit for reuse. DMC is primarily collected from this side stream for recovery. The reason for collecting a small amount of water from the ME and DMC liquid stream is that H2O forms an azeotrope with ML or DMC; collecting it as an azeotrope ensures that the formate aqueous solution in the tower bottom is free of organic matter.

[0079] In step 2), the bottom of the light component recovery tower is heated by a reboiler.

[0080] In step 2), the formate aqueous solution liquid phase stream is extracted through the bottom pump pipeline under the action of the bottom pump.

[0081] In step 2), the liquid phase of the formate aqueous solution is an aqueous solution of formate, and the aqueous solution of formate is dried in an evaporator to obtain solid formate.

[0082] In one embodiment, the evaporator is a conventionally used evaporator.

[0083] In one embodiment, the formate solution contains, by mass percentage, 50-75 wt% formate and 25-50 wt% water.

[0084] In one embodiment, the concentration of carbonate in the formate solution is ≤0.2 wt%. The carbonate is selected from at least one of potassium carbonate (K2CO3), sodium carbonate (Na2CO3), and calcium carbonate (CaCO3), preferably potassium carbonate (K2CO3).

[0085] In one embodiment, the drying temperature is 60-120°C, specifically 60-70°C, 70-110°C, or 110-120°C, preferably 70-110°C.

[0086] In one embodiment, the drying time is 5-11 hours.

[0087] In one embodiment, the drying process is performed at least once, preferably twice.

[0088] In a preferred embodiment, when the drying is performed once, the formate concentration in the obtained formate solution is 50-75 wt%, and the carbonate concentration is ≤0.5 wt%; when the drying is performed twice, the formate concentration in the obtained solid is ≥96 wt%, and the carbonate concentration is ≤0.5 wt%.

[0089] In one embodiment, the formate is selected from at least one of potassium formate (KF), sodium formate, and calcium formate, preferably potassium formate (KF).

[0090] Since the total amount of alcohol ester byproducts in syngas-to-ethylene glycol production is relatively small, a 200,000 t / a syngas-to-ethylene glycol plant produces approximately 1.5 t / h of alcohol ester byproducts containing MF. Drying formate aqueous solutions into solids is not economically viable, and fluids are significantly cheaper to store and transport than solids; therefore, aqueous formate solutions are preferred as the product. Furthermore, since an important use of potassium formate (KF) is as a soil conditioner, it can be sold locally to reduce transportation costs; therefore, aqueous KOH solutions are preferred for producing KF.

[0091] The fourth aspect of the present invention provides an experimental method for treating alcohol ester byproducts in the production of ethylene glycol from syngas, using the above-mentioned experimental system for treating alcohol ester byproducts in the production of ethylene glycol from syngas, comprising: adding alcohol ester byproducts containing MF to a flask, placing it in an oil bath for stirring and heating, then taking alkali solution from an alkali solution tank and adding it to the flask for mixing and reaction, and then removing the flask and cooling it to obtain a reaction solution.

[0092] In the above method, the MF-containing alcohol ester byproduct includes at least MF.

[0093] In one embodiment, the MF-containing alcohol ester byproduct further includes at least one selected from DMC, ML, and ME.

[0094] In the above method, the heating temperature is 60-65℃, preferably 63℃.

[0095] In the above method, the addition of the MF-containing alcohol ester byproduct and the alkaline solution conforms to formula (1).

[0096] The formula (1) is: (mass of alcohol ester byproduct containing MF × mass concentration of MF in alcohol ester byproduct containing MF / 60.05) / (mass of alkaline solution × mass concentration of alkali in alkaline solution / molecular weight of alkali) = 1: 0.9~1.1.

[0097] In the above method, the alkali in the alkaline solution is selected from at least one of potassium hydroxide (KOH), sodium hydroxide (NaOH), and calcium hydroxide (Ca(OH)2), preferably potassium hydroxide (KOH).

[0098] In the above method, the alkaline solution is an aqueous solution of alkali, and the concentration of alkali in the alkaline solution is 25-50 wt%, specifically 25-30 wt%, 30-45 wt%, or 45-50 wt%, preferably 30-45 wt%.

[0099] In the above method, the pH of the reaction is 6-9. A pH meter is used to monitor the pH value in real time, and the pH value is controlled by adjusting the alkali dosing rate of the metering pump.

[0100] In the above method, the reaction time is 40-50 min, preferably 45 min.

[0101] In the above method, the cooling is carried out in an ice bath.

[0102] In the above method, the cooling to room temperature is 20-30°C.

[0103] The fifth aspect of the present invention provides a formate, which is obtained by the above-mentioned production method for treating alcohol ester by-products in the production of ethylene glycol from syngas or by the experimental method for treating alcohol ester by-products in the production of ethylene glycol from syngas.

[0104] The sixth aspect of the present invention provides the use of formate in oil fields, in the production of potassium diformate, or as a hydrogen storage and production carrier.

[0105] In the above-mentioned uses, the formate is used as a snow-melting agent and / or soil conditioner in oil fields.

[0106] The following specific examples illustrate the implementation of the present invention. Those skilled in the art can easily understand other advantages and effects of the present invention from the content disclosed in this specification. The present invention can also be implemented or applied through other different specific embodiments, and various details in this specification can also be modified or changed based on different viewpoints and applications without departing from the spirit of the present invention.

[0107] In the following embodiments, unless otherwise specified, the raw materials or processing techniques are conventional commercially available raw materials or conventional processing techniques in the art.

[0108] Example 1

[0109] The stream of alcohol ester byproducts containing MF from the syngas to ethylene glycol process is processed in a manner such as... Figure 1 The processing system shown is used for the production of MF-containing alcohol ester byproducts. Specifically, the stream of MF-containing alcohol ester byproducts comes from the top of the DMC recovery tower of the syngas-to-ethylene glycol main unit, with a composition of ML 6.7 wt%, MN 18.2 wt%, ME 11.8 wt%, DMC 1.0 wt%, and MF 62.3 wt%, and is fed into a stirred tank reactor at a flow rate of 0.60 t / h; a 40% KOH aqueous solution is also fed into the stirred tank reactor at a flow rate of 0.84 t / h. The reaction temperature is controlled at 80 °C, the reaction pressure at 0.5 MPa, and the reaction pH at 8.0. In the stirred tank reactor, MF reacts with KOH to generate a reaction solution containing potassium formate (KF).

[0110] The reaction liquid is drawn from the stirred tank reactor and fed into the light component recovery tower for separation. The operating conditions of the light component recovery tower are 0.6 MPa, reflux ratio 20, top temperature 40°C, and bottom temperature 164°C. The non-condensable gas stream collected from the top of the tower is a small amount of non-condensable gas, mainly N2; the liquid stream of MN and MF collected from the top of the tower mainly consists of MN and MF, with a specific composition of ML 1.3 wt%, MN 93.3 wt%, ME 0.2 wt%, and MF 5.2 wt%, and a collection rate of 110 kg / h, which is sent to the esterification tower of the syngas to ethylene glycol main unit for reuse. The liquid stream of ML and ME collected from the first side line is mainly an azeotrope of ML and ME, with a specific composition of ML 57.1 wt%, MN 2.2 wt%, ME 27.3 wt%, DMC 1.0 wt%, and MF 12.5 wt%, and a collection rate of 60 kg / h, which is sent as fuel to the heating furnace of the utility project for combustion and denitrification emission. The second side-stream extraction pipeline yields a liquid stream of ME and DMC, primarily an azeotrope of ME and DMC. The specific composition is: ML 1.6 wt%, MN 1.9 wt%, ME 89.8 wt%, DMC 2.0 wt%, MF 0.6 wt%, with the balance being water. The extraction rate is 270 kg / h, which is then sent to the methanol dehydration tower of the syngas-to-ethylene glycol main unit for reuse. The bottom of the tower yields an aqueous solution of KF, sample #1, with a specific composition of KF 50.3 wt%, K₂CO₃ 0.1 wt%, and the balance being water. The extraction rate is 1000 kg / h.

[0111] Example 2

[0112] The KF aqueous solution sample 1# obtained in Example 1 was dried twice in an evaporator at 100°C for 6 hours. During the first drying, a 50.3% KF aqueous solution was introduced into the evaporator to evaporate the water, yielding a 75% KF aqueous solution. During the second drying, the 75% KF aqueous solution was again introduced into the evaporator to further evaporate the water, yielding potassium formate solid with a content ≥96wt%, of which the K2CO3 content ≤0.3wt%. The desired potassium formate solid sample 1* was obtained, exhibiting a uniform appearance.

[0113] Example 3

[0114] The stream of alcohol ester byproducts containing MF from the syngas to ethylene glycol process is processed in a manner such as... Figure 1The processing system shown is used for the production. Specifically, the alcohol ester byproduct containing MF comes from the top of the DMC recovery tower of the syngas-to-ethylene glycol main unit, with a composition of ML 10.5 wt%, MN 12.6 wt%, ME 12.5 wt%, DMC 5.7 wt%, and MF 58.8 wt%, and is fed into a stirred tank reactor at a flow rate of 0.60 t / h; a 32% NaOH aqueous solution is also fed into the stirred tank reactor at a flow rate of 0.60 t / h. The reaction temperature is controlled at 60°C, the reaction pressure at 0.5 MPa, and the reaction pH at 6.5. In the stirred tank reactor, MF reacts with NaOH to produce a reaction solution containing sodium formate (NaF).

[0115] The reaction liquid is drawn from the stirred tank reactor and fed into the light component recovery tower for separation. The operating conditions of the light component recovery tower are 0.6 MPa, reflux ratio 15, tower top temperature 52℃, and tower bottom temperature 165℃. The non-condensable gas stream collected from the tower top is a small amount of non-condensable gas, mainly N2; the liquid stream of MN and MF collected from the tower top is mainly MN and MF, with a specific composition of ML 6.0 wt%, MN 60.0 wt%, ME 2.6 wt%, and MF 31.4 wt%, and a collection rate of 120 kg / h, which is sent to the esterification tower of the syngas to ethylene glycol main unit for reuse. The liquid stream of ML and ME collected from the first side line is mainly an azeotrope of ML and ME, with a specific composition of ML 50.1 wt%, MN 1.3 wt%, ME 26.7 wt%, DMC 1.8 wt%, and MF 20.2 wt%, and a collection rate of 100 kg / h, which is sent as fuel to the heating furnace of the utility project for combustion and denitrification emission. The second side-stream extraction pipeline yielded a liquid stream of ME and DMC, primarily an azeotrope of ME and DMC. The specific composition was ML 2.3 wt%, MN 1.1 wt%, ME 78.5 wt%, DMC 12.2 wt%, MF 2.4 wt%, with the balance being water. The extraction rate was 255 kg / h, which was then sent to the methanol dehydration tower of the syngas-to-ethylene glycol main unit for reuse. The tower bottom was a NaF aqueous solution sample #2, with a specific composition of NaF 44.8 wt%, Na₂CO₃ 0.16 wt%, and the balance being water. The extraction rate was 731 kg / h.

[0116] Example 4

[0117] The NaF aqueous solution sample 2# obtained in Example 3 was dried twice in an evaporator at 100°C for 6 hours. During the first drying, a 44.8% NaF aqueous solution was introduced into the evaporator to evaporate the water, yielding a 75% NaF aqueous solution. During the second drying, the 75% NaF aqueous solution was again introduced into the evaporator to further evaporate the water, yielding a NaF solid with a content ≥96wt%, of which the K2CO3 content ≤0.5wt%. The desired sodium formate solid sample 2* was obtained, exhibiting a uniform appearance.

[0118] Comparative Example 1

[0119] The MF-containing alcohol ester byproduct stream, as described in Example 3, was fed into a stirred tank reactor at a flow rate of 0.60 t / h; a 32% NaOH aqueous solution was also fed into the stirred tank reactor at a flow rate of 0.60 t / h. The reaction temperature was controlled at 60°C, the reaction pressure at 0.5 MPa, and the reaction pH at 9. In the stirred tank reactor, MF reacted with NaOH to generate a reaction solution containing sodium formate (NaF).

[0120] The remaining steps of the reaction were the same as in Example 3, yielding a comparative sample 1 of NaF aqueous solution, specifically composed of 55.7 wt% NaF, 1.1 wt% Na2CO3, with the balance being water, and a production rate of 916 kg / h. Due to the high pH control of the reaction, excessive DMC decomposition occurred, resulting not only in DMC loss but also in a high content of Na2CO3 impurities in the NaF aqueous solution.

[0121] Comparative Example 2

[0122] A reaction solution containing potassium formate (KF) was generated under the same conditions as in Example 1.

[0123] The reaction solution was drawn from the stirred tank reactor and fed into a light component recovery tower for separation. The operating conditions of the light component recovery tower were 1.1 MPa, reflux ratio 40, top temperature 65°C, and bottom temperature 188°C. The remaining conditions for the reaction solution were the same as in Example 1. A KF aqueous solution was obtained as control sample 2, with the specific composition of KF 50.4 wt%, K2CO3 0.1 wt%, and the balance being water, and the production rate was 1000 kg / h. Due to the bottom temperature reaching 188°C, a higher level of heating steam was required, increasing operating costs.

[0124] Comparative Example 3

[0125] The KF aqueous solution sample 1# obtained in Example 1 was dried once in an evaporator at 100°C for 12 hours. During the first drying, 50.3% of the KF aqueous solution was introduced into the evaporator to evaporate the water, yielding potassium formate solid with a content ≥96wt%, of which the K2CO3 content was ≤0.3wt%. Potassium formate solid control sample 1 was obtained. Compared to potassium formate solid sample 1* obtained in Example 2, potassium formate solid control sample 1 had a less uniform appearance.

[0126] Comparative Example 4

[0127] The KF aqueous solution sample 1# obtained in Example 1 was dried twice in an evaporator at 100°C for 4 hours. During the first drying, a 50.3% KF aqueous solution was introduced into the evaporator to evaporate the water, yielding a 75% KF aqueous solution. During the second drying, the 75% KF aqueous solution was again introduced into the evaporator to further evaporate the water, yielding potassium formate solid with a content ≥96 wt%, of which the K2CO3 content was ≤0.3 wt%. A potassium formate solid control sample 2 was obtained. Compared to the potassium formate solid sample 1* obtained in Example 2, the appearance of potassium formate solid control sample 2 was less uniform.

[0128] Example 5

[0129] MF was used as an alcohol ester byproduct containing MF in, for example Figure 2 The treatment experiment system shown was used for the process. Specifically, 100g of MF was added to a 500ml glass flask, which was then placed in an oil bath. A condenser was installed on top of the flask and cooled by chilled water. A magnetic stirrer was started and the mixture was heated to a constant temperature of 63°C. A 40wt% KOH aqueous solution was added to the flask from the alkali tank using a metering pump for the reaction. The pH value was monitored in real time using a pH meter, and the pH value was controlled to 7 by adjusting the alkali addition rate of the metering pump.

[0130] After reacting for 45 minutes, the 500 ml glass flask was immersed in an ice bath to cool and stop the reaction. Analysis of the reaction solution showed that the conversion rate of MF to potassium formate (KF) was 91%.

[0131] Example 6

[0132] MF was used as an alcohol ester byproduct containing MF in, for example Figure 2 The treatment experiment system shown was used for the process. Specifically, 100g of MF was added to a 500ml glass flask, which was then placed in an oil bath. A condenser was installed on top of the flask and cooled by chilled water. A magnetic stirrer was started and the temperature was heated to a constant 63°C. A 32wt% NaOH aqueous solution was added to the flask from the alkali tank using a metering pump for the reaction. The pH value was monitored in real time using a pH meter, and the pH value was controlled to 7.5 by adjusting the alkali addition rate of the metering pump.

[0133] After reacting for 45 minutes, the 500 ml glass flask was immersed in an ice bath to cool and stop the reaction. Analysis of the reaction solution showed that the conversion rate of MF to sodium formate was 94%.

[0134] Example 7

[0135] MF was used as an alcohol ester byproduct containing MF in, for example Figure 2The treatment experiment system shown was used for the process. Specifically, 100g of MF was added to a 500ml glass flask, which was then placed in an oil bath. A condenser was installed on top of the flask and cooled by chilled water. A magnetic stirrer was started and the temperature was heated to a constant 63°C. A 40wt% KOH aqueous solution was added to the flask from the alkali tank using a metering pump for the reaction. The pH value was monitored in real time using a pH meter, and the pH value was controlled to 8.0 by adjusting the alkali addition rate of the metering pump.

[0136] After reacting for 45 minutes, the 500 ml glass flask was immersed in an ice bath to cool and stop the reaction. Analysis of the reaction solution showed that the conversion rate of MF to potassium formate (KF) was ≥98%.

[0137] Example 8

[0138] MF was used as an alcohol ester byproduct containing MF in, for example Figure 2 The treatment experiment system shown was used for the process. Specifically, 100g of MF was added to a 500ml glass flask, which was then placed in an oil bath. A condenser was installed on top of the flask and cooled by chilled water. A magnetic stirrer was started and the temperature was heated to a constant 63°C. A 32%wt NaOH aqueous solution was added to the flask using a metering pump. The pH value was monitored in real time using a pH meter, and the pH value was controlled to 9.0 by adjusting the alkali addition rate of the metering pump.

[0139] After reacting for 45 minutes, the 500 ml glass flask was immersed in an ice bath to cool and stop the reaction. Analysis of the reaction solution showed that the conversion rate of MF to sodium formate was ≥98%.

[0140] Example 9

[0141] MF and DMC were used as MF-containing alcohol ester byproducts in, for example... Figure 2 The experimental system shown was used for the treatment. Specifically, 80g of MF and 20g of DMC were added to a 500ml glass flask, which was then placed in an oil bath. A condenser was installed on top of the flask and cooled by chilled water. A magnetic stirrer was started and the mixture was heated to a constant temperature of 63°C. A 40%wt KOH aqueous solution was added to the flask using a metering pump. The pH value was monitored in real time using a pH meter, and the pH value was controlled to 6.5 by adjusting the alkali addition rate of the metering pump.

[0142] After reacting for 45 minutes, the 500 ml glass flask was immersed in an ice bath to cool and stop the reaction. Analysis of the reaction solution showed that the conversion rate of MF to potassium formate (KF) was 83%, and the conversion rate of DMC was 3%.

[0143] Example 10

[0144] MF and DMC were used as MF-containing alcohol ester byproducts in, for example... Figure 2 The treatment experiment system shown was used for the process. Specifically, 80g of MF and 20g of DMC were added to a 500ml glass flask, which was then placed in an oil bath. A condenser was installed on top of the flask and cooled by chilled water. A magnetic stirrer was started and the temperature was heated to a constant 63°C. A 32%wt NaOH aqueous solution was added to the flask using a metering pump. The pH value was monitored in real time using a pH meter, and the pH value was controlled to 7.5 by adjusting the alkali addition rate of the metering pump.

[0145] After reacting for 45 minutes, the 500 ml glass flask was immersed in an ice bath to cool and stop the reaction. Analysis of the reaction solution showed that the conversion rate of MF to sodium formate was 87%, and the conversion rate of DMC was 11%.

[0146] Example 11

[0147] MF and DMC were used as MF-containing alcohol ester byproducts in, for example... Figure 2 The treatment experiment system shown was used for the process. Specifically, 80g of MF and 20g of DMC were added to a 500ml glass flask, which was then placed in an oil bath. A condenser was installed on top of the flask and cooled by chilled water. A magnetic stirrer was started and the temperature was heated to a constant 63°C. A 40%wt KOH aqueous solution was added to the flask using a metering pump. The pH value was monitored in real time using a pH meter, and the pH value was controlled to 8.5 by adjusting the alkali addition rate of the metering pump.

[0148] After reacting for 45 minutes, the 500 ml glass flask was immersed in an ice bath to cool and stop the reaction. Analysis of the reaction solution showed that the conversion rate of MF to potassium formate (KF) was 94%, and the conversion rate of DMC was 11%.

[0149] Example 12

[0150] MF and DMC were used as MF-containing alcohol ester byproducts in, for example... Figure 2 The experimental system shown was used for the treatment. Specifically, 80g of MF and 20g of DMC were added to a 500ml glass flask, which was then placed in an oil bath. A condenser was placed on top of the flask and cooled by chilled water. A magnetic stirrer was started and the mixture was heated to a constant temperature of 63°C. A 40%wt KOH aqueous solution was added to the flask using a metering pump. The pH value was monitored in real time using a pH meter, and the pH value was controlled to be 9.0 by adjusting the alkali addition rate of the metering pump.

[0151] After reacting for 45 minutes, the 500 ml glass flask was immersed in an ice bath to cool and stop the reaction. Analysis of the reaction solution showed that the conversion rate of MF to potassium formate (KF) was ≥98%, and the conversion rate of DMC was 25%.

[0152] Example 13

[0153] MF and DMC were used as MF-containing alcohol ester byproducts in, for example... Figure 2 The treatment experiment system shown was used for the process. Specifically, 99g of MF and 1g of DMC were added to a 500ml glass flask, which was then placed in an oil bath. A condenser was installed on top of the flask and cooled by chilled water. A magnetic stirrer was started and the temperature was heated to 70°C. A 32%wt NaOH aqueous solution was added to the flask using a metering pump. The pH value was monitored in real time using a pH meter, and the pH value was controlled to 6.5 by adjusting the alkali addition rate of the metering pump.

[0154] After reacting for 45 minutes, the 500 ml glass flask was immersed in an ice bath to cool and stop the reaction. Analysis of the reaction solution showed that the conversion rate of MF to sodium formate was 84%, and the conversion rate of DMC was 6%.

[0155] Example 14

[0156] MF and DMC were used as MF-containing alcohol ester byproducts in, for example... Figure 2 The experimental system shown was used for the treatment. Specifically, 99g of MF and 1g of DMC were added to a 500ml glass flask, which was then placed in an oil bath. A condenser was placed on top of the flask and cooled by chilled water. A magnetic stirrer was started and the mixture was heated to a constant temperature of 70°C. A 40%wt KOH aqueous solution was added to the flask using a metering pump. The pH value was monitored in real time using a pH meter, and the pH value was controlled to 7.5 by adjusting the alkali addition rate of the metering pump.

[0157] After reacting for 45 minutes, the 500 ml glass flask was immersed in an ice bath to cool and stop the reaction. Analysis of the reaction solution showed that the conversion rate of MF to potassium formate (KF) was 93%, and the conversion rate of DMC was 9%.

[0158] Example 15

[0159] MF and DMC were used as MF-containing alcohol ester byproducts in, for example... Figure 2 The experimental system shown was used for the treatment. Specifically, 99g of MF and 1g of DMC were added to a 500ml glass flask, which was then placed in an oil bath. A condenser was installed on top of the flask and cooled by chilled water. A magnetic stirrer was started and the mixture was heated to a constant temperature of 70°C. A 40%wt KOH aqueous solution was added to the flask using a metering pump. The pH value was monitored in real time using a pH meter, and the pH value was controlled to 8.0 by adjusting the alkali addition rate of the metering pump.

[0160] After reacting for 45 minutes, the 500 ml glass flask was immersed in an ice bath to cool and stop the reaction. Analysis of the reaction solution showed that the conversion rate of MF to potassium formate (KF) was ≥98%, and the conversion rate of DMC was 30%.

[0161] Example 16

[0162] MF and DMC were used as MF-containing alcohol ester byproducts in, for example... Figure 2 The treatment experiment system shown was used for the process. Specifically, 99.5g of MF and 0.5g of DMC were added to a 500ml glass flask, which was then placed in an oil bath. A condenser was installed on top of the flask and cooled by chilled water. A magnetic stirrer was started and the mixture was heated to a constant temperature of 50°C. A 40%wt KOH aqueous solution was added to the flask using a metering pump. The pH value was monitored in real time using a pH meter, and the pH value was controlled to 6.0 by adjusting the alkali addition rate of the metering pump.

[0163] After reacting for 45 minutes, the 500 ml glass flask was immersed in an ice bath to cool and stop the reaction. Analysis of the reaction solution showed that the conversion rate of MF to potassium formate (KF) was 74%, and the conversion rate of DMC was 2%.

[0164] Example 17

[0165] MF and DMC were used as MF-containing alcohol ester byproducts in, for example... Figure 2 The treatment experiment system shown was used for the process. Specifically, 99.5g of MF and 0.5g of DMC were added to a 500ml glass flask, which was then placed in an oil bath. A condenser was installed on top of the flask and cooled by chilled water. A magnetic stirrer was started and the mixture was heated to a constant temperature of 50°C. A 40%wt KOH aqueous solution was added to the flask using a metering pump to initiate the reaction. The pH value was monitored in real time using a pH meter, and the pH value was controlled to 6.5 by adjusting the alkali addition rate of the metering pump.

[0166] After reacting for 45 minutes, the 500 ml glass flask was immersed in an ice bath to cool and stop the reaction. Analysis of the reaction solution showed that the conversion rate of MF to potassium formate (KF) was 79%, and the conversion rate of DMC was 4%.

[0167] Example 18

[0168] MF and DMC were used as MF-containing alcohol ester byproducts in, for example... Figure 2The treatment experiment system shown was used for the process. Specifically, 99.5g of MF and 0.5g of DMC were added to a 500ml glass flask, which was then placed in an oil bath. A condenser was installed on top of the flask and cooled by chilled water. A magnetic stirrer was started and the temperature was heated to 50°C. A 40%wt KOH aqueous solution was added to the flask using a metering pump. The pH value was monitored in real time using a pH meter, and the pH value was controlled to 7.0 by adjusting the alkali addition rate of the metering pump.

[0169] After reacting for 45 minutes, the 500 ml glass flask was immersed in an ice bath to cool and stop the reaction. Analysis of the reaction solution showed that the conversion rate of MF to potassium formate (KF) was 83%, and the conversion rate of DMC was 7%.

[0170] Example 19

[0171] MF and DMC were used as MF-containing alcohol ester byproducts in, for example... Figure 2 The experimental system shown was used for the treatment. Specifically, 99.5g of MF and 0.5g of DMC were added to a 500ml glass flask, which was then placed in an oil bath. A condenser was placed on top of the flask and cooled by chilled water. A magnetic stirrer was started and the mixture was heated to a constant temperature of 50°C. A 40%wt KOH aqueous solution was added to the flask using a metering pump. The pH value was monitored in real time using a pH meter, and the pH value was controlled to 8.0 by adjusting the alkali addition rate of the metering pump.

[0172] After reacting for 45 minutes, the 500 ml glass flask was immersed in an ice bath to cool and stop the reaction. Analysis of the reaction solution showed that the conversion rate of MF to potassium formate (KF) was 89%, and the conversion rate of DMC was 8%.

[0173] Example 20

[0174] MF and DMC were used as MF-containing alcohol ester byproducts in, for example... Figure 2 The treatment experiment system shown was used for the process. Specifically, 99.5g of MF and 0.5g of DMC were added to a 500ml glass flask, which was then placed in an oil bath. A condenser was installed on top of the flask and cooled by chilled water. A magnetic stirrer was started and the mixture was heated to a constant temperature of 50°C. A 40%wt KOH aqueous solution was added to the flask using a metering pump. The pH value was monitored in real time using a pH meter, and the pH value was controlled to be 9.0 by adjusting the alkali addition rate of the metering pump.

[0175] After reacting for 45 minutes, the 500 ml glass flask was immersed in an ice bath to cool and stop the reaction. Analysis of the reaction solution showed that the conversion rate of MF to potassium formate (KF) was 96%, and the conversion rate of DMC was 22%.

[0176] Example 21

[0177] MF and DMC were used as MF-containing alcohol ester byproducts in, for example... Figure 2 The treatment experiment system shown was used for the process. Specifically, 97g of MF and 3g of DMC were added to a 500ml glass flask, which was then placed in an oil bath. A condenser was installed on top of the flask and cooled by chilled water. A magnetic stirrer was started and the temperature was heated to 80°C. A 32%wt NaOH aqueous solution was added to the flask using a metering pump. The pH value was monitored in real time using a pH meter, and the pH value was controlled to 6.0 by adjusting the alkali addition rate of the metering pump.

[0178] After reacting for 45 minutes, the 500 ml glass flask was immersed in an ice bath to cool and stop the reaction. Analysis of the reaction solution showed that the conversion rate of MF to sodium formate was 76%, and the conversion rate of DMC was 4%.

[0179] Example 22

[0180] MF and DMC were used as MF-containing alcohol ester byproducts in, for example... Figure 2 The treatment experiment system shown was used for the process. Specifically, 97g of MF and 3g of DMC were added to a 500ml glass flask, which was then placed in an oil bath. A condenser was installed on top of the flask and cooled by chilled water. A magnetic stirrer was started and the mixture was heated to a constant temperature of 80°C. A 40%wt KOH aqueous solution was added to the flask using a metering pump. The pH value was monitored in real time using a pH meter, and the pH value was controlled to 6.5 by adjusting the alkali addition rate of the metering pump.

[0181] After reacting for 45 minutes, the 500 ml glass flask was immersed in an ice bath to cool and stop the reaction. Analysis of the reaction solution showed that the conversion rate of MF to potassium formate (KF) was 86%, and the conversion rate of DMC was 6%.

[0182] Example 23

[0183] MF and DMC were used as MF-containing alcohol ester byproducts in, for example... Figure 2 The treatment experiment system shown was used for the process. Specifically, 97g of MF and 3g of DMC were added to a 500ml glass flask, which was then placed in an oil bath. A condenser was installed on top of the flask and cooled by chilled water. A magnetic stirrer was started and the temperature was heated to 80°C. A 32%wt NaOH aqueous solution was added to the flask using a metering pump. The pH value was monitored in real time using a pH meter, and the pH value was controlled to 7.5 by adjusting the alkali addition rate of the metering pump.

[0184] After reacting for 45 minutes, the 500 ml glass flask was immersed in an ice bath to cool and stop the reaction. Analysis of the reaction solution showed that the conversion rate of MF to sodium formate was 90%, and the conversion rate of DMC was 12%.

[0185] Example 24

[0186] MF and DMC were used as MF-containing alcohol ester byproducts in, for example... Figure 2 The treatment experiment system shown was used for the process. Specifically, 97g of MF and 3g of DMC were added to a 500ml glass flask, which was then placed in an oil bath. A condenser was installed on top of the flask and cooled by chilled water. A magnetic stirrer was started and the mixture was heated to a constant temperature of 80°C. A 40%wt KOH aqueous solution was added to the flask using a metering pump. The pH value was monitored in real time using a pH meter, and the pH value was controlled to 8.5 by adjusting the alkali addition rate of the metering pump.

[0187] After reacting for 45 minutes, the 500 ml glass flask was immersed in an ice bath to cool and stop the reaction. Analysis of the reaction solution showed that the conversion rate of MF to potassium formate (KF) was ≥98%, and the conversion rate of DMC was 33%.

[0188] Example 25

[0189] MF, ML, ME, and DMC were used as MF-containing alcohol ester byproducts in... Figure 2 The experimental system shown was used for the treatment. Specifically, 60g MF, 12g ML, 23g ME, and 5g DMC were added to a 500ml glass flask, which was then placed in an oil bath. A condenser was installed on top of the flask and cooled by chilled water. A magnetic stirrer was started and the mixture was heated to a constant temperature of 65°C. A 32%wt NaOH aqueous solution was added to the flask using a metering pump. The pH value was monitored in real time using a pH meter, and the pH value was controlled to 6.4 by adjusting the alkali addition rate of the metering pump.

[0190] After reacting for 45 minutes, the 500 ml glass flask was immersed in an ice bath to cool and stop the reaction. Analysis of the reaction solution showed that the conversion rate of MF to sodium formate was ≥83%, and the conversion rate of DMC was 4%.

[0191] Example 26

[0192] MF, ML, ME, and DMC were used as MF-containing alcohol ester byproducts in... Figure 2The experimental system shown was used for the treatment. Specifically, 62g MF, 6g ML, 26g ME, and 6g DMC were added to a 500ml glass flask, which was then placed in an oil bath. A condenser was installed on top of the flask and cooled by chilled water. A magnetic stirrer was started and the mixture was heated to a constant temperature of 63°C. A 40% wt KOH aqueous solution was added to the flask using a metering pump. The pH value was monitored in real time using a pH meter, and the pH value was controlled to 6.8 by adjusting the alkali addition rate of the metering pump.

[0193] After reacting for 45 minutes, the 500 ml glass flask was immersed in an ice bath to cool and stop the reaction. Analysis of the reaction solution showed that the conversion rate of MF to potassium formate (KF) was ≥88%, and the conversion rate of DMC was 5%.

[0194] Example 27

[0195] MF, ML, ME, and DMC were used as MF-containing alcohol ester byproducts in... Figure 2 The treatment experiment system shown was used for the process. Specifically, 57g MF, 0.5g ML, 34.5g ME, and 8g DMC were added to a 500ml glass flask, which was then placed in an oil bath. A condenser was installed on top of the flask and cooled by chilled water. A magnetic stirrer was started and the temperature was heated to 70°C. A 32%wt NaOH aqueous solution was added to the flask using a metering pump. The pH value was monitored in real time using a pH meter, and the pH value was controlled to 7.5 by adjusting the alkali addition rate of the metering pump.

[0196] After reacting for 45 minutes, the 500 ml glass flask was immersed in an ice bath to cool and stop the reaction. Analysis of the reaction solution showed that the conversion rate of MF to sodium formate was ≥94%, and the conversion rate of DMC was 11%.

[0197] Example 28

[0198] MF, ML, ME, and DMC were used as MF-containing alcohol ester byproducts in... Figure 2 The treatment experiment system shown was used for the process. Specifically, 30g MF, 1.5g ML, 41g ME, and 7.5g DMC were added to a 500ml glass flask, which was then placed in an oil bath. A condenser was installed on top of the flask and cooled by chilled water. A magnetic stirrer was started and the temperature was heated to 70°C. A 40%wt KOH aqueous solution was added to the flask using a metering pump. The pH value was monitored in real time using a pH meter, and the pH value was controlled to 7.0 by adjusting the alkali addition rate of the metering pump.

[0199] After reacting for 45 minutes, the 500 ml glass flask was immersed in an ice bath to cool and stop the reaction. Analysis of the reaction solution showed that the conversion rate of MF to sodium formate was ≥90%, and the conversion rate of DMC was 6%.

[0200] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention in any form or substance. It should be noted that those skilled in the art can make various improvements and additions without departing from the method of the present invention, and these improvements and additions should also be considered within the scope of protection of the present invention. Any modifications, alterations, and equivalent changes made by those skilled in the art based on the above-disclosed technical content without departing from the spirit and scope of the present invention are equivalent embodiments of the present invention. Furthermore, any modifications, alterations, and evolutions made to the above embodiments based on the essential technology of the present invention still fall within the scope of the technical solution of the present invention.

Claims

1. A continuous processing system for alcohol ester byproducts in the production of ethylene glycol from syngas, characterized in that, A stirred tank reactor (a) and a light component recovery tower (g) are sequentially connected along the input direction of the alcohol ester byproduct stream containing methyl formate from the syngas to ethylene glycol process. The stirred tank reactor (a) is connected to an alcohol ester byproduct stream pipeline (A) and an alkali inlet pipeline (B). The rectification section of the light component recovery tower (g) is sequentially connected from top to bottom to a first side-line outlet pipeline (E) and a second side-line outlet pipeline (F). A cooling system is sequentially connected along the liquid phase stream output direction outside the top of the light component recovery tower (g). The light component recovery tower (g) is equipped with a condenser (c) and a reflux tank (d). The condenser (c) and reflux tank (d) are connected to the top of the light component recovery tower (g) to form a loop. The condenser (c) is also connected to the top non-condensable gas output pipeline (C). The reflux tank (d) is also connected to the top liquid phase collection pipeline (D). The bottom of the light component recovery tower (g) is equipped with a reboiler (f). The reboiler (f) is connected to the bottom of the light component recovery tower (g) to form a loop. The bottom of the light component recovery tower (g) is also connected to the bottom collection pipeline (G).

2. The continuous processing system for alcohol ester byproducts in the production of ethylene glycol from syngas according to claim 1, characterized in that, Includes one or more of the following conditions: A1) The stirred tank reactor (a) and the light component recovery tower (g) are connected by a first connecting pipe (H), and a discharge pump (b) is provided on the first connecting pipe (H); preferably, one end of the first connecting pipe (H) is connected to the bottom of the stirred tank reactor (a), and the other end of the first connecting pipe (H) is connected to the rectification section of the light component recovery tower (g); A2) The alcohol ester by-product pipeline (A) and the alkali inlet pipeline (B) are both connected to the top of the stirred tank reactor (a); A3) The rectification section of the light component recovery tower (g) is provided with at least three rectification zones from top to bottom, and adjacent rectification zones are spaced apart; preferably, the rectification zones include a first rectification zone (I1), a second rectification zone (I2), and a third rectification zone (I3) from top to bottom, the second rectification zone (I2) is spaced apart from the first rectification zone (I1) and the third rectification zone (I3), a first side-line outlet pipeline (E) is connected between the first rectification zone (I1) and the second rectification zone (I2), and a second side-line outlet pipeline (F) is connected between the second rectification zone (I2) and the third rectification zone (I3); more preferably, a first connecting pipeline (H) is connected below the third rectification zone (I3); A4) The condenser (c), reflux tank (d), and the top of the light component recovery tower (g) are connected by a second connecting pipe (J) to form a loop. A reflux pump (e) is provided on the second connecting pipe (J) between the reflux tank (d) and the light component recovery tower (g). The second connecting pipe (J) is also connected to the liquid phase extraction pipe (D) at the top of the tower. Preferably, the liquid phase extraction pipe (D) at the top of the tower is connected to the second connecting pipe (J) between the reflux pump (e) and the top of the light component recovery tower (g). A5) The bottom pump (h) is installed on the bottom pumping pipeline (G) of the bottom pumping pipeline.

3. An experimental system for treating alcohol ester byproducts in the production of ethylene glycol from syngas, characterized in that, The device includes an oil bath (2), a flask (1), a metering pump (5), and a pH meter (4). The flask (1) is placed inside the oil bath (2). The flask (1) is connected to the metering pump (5) via a pipeline. The metering pump (5) is also connected to an alkali tank (6). The flask (1) is also connected to a condenser (3). The pH meter (4) is inserted into the flask (1).

4. A method for treating alcohol ester byproducts in the production of ethylene glycol from syngas, comprising: The alcohol ester byproduct stream containing methyl formate from the syngas to ethylene glycol process is directly mixed with an alkaline solution without separation or purification. The resulting reaction solution is then distilled to collect non-condensable gas stream, MN and MF liquid stream, ML and ME liquid stream, ME and DMC liquid stream, and formate aqueous solution liquid stream. DMC is recovered through the ME and DMC liquid stream, and formate is recovered through the formate aqueous solution liquid stream.

5. The method for treating alcohol ester byproducts in the production of ethylene glycol from syngas according to claim 4, characterized in that, The processing method, employing the continuous processing production system for alcohol ester byproducts in the syngas-to-ethylene glycol production according to any one of claims 1-2, includes the following steps: 1) The alcohol ester byproduct stream containing methyl formate from the syngas to ethylene glycol process is directly fed into the stirred tank reactor with alkaline solution without separation and purification to obtain a reaction solution. The MF in the reaction solution reacts with the alkali in the alkaline solution to obtain formate. The reaction solution also includes DMC, ML, ME, MN, water and unreacted MF. 2) The reaction liquid is fed into the light component recovery tower for distillation. Non-condensable gas stream and MN and MF liquid stream are collected from the top of the light component recovery tower. ML and ME liquid streams are collected from the rectification section of the light component recovery tower via the first side line collection pipeline, and ME and DMC liquid streams are collected via the second side line collection pipeline. Formate aqueous solution liquid stream is collected from the bottom of the light component recovery tower. DMC is then recovered through the ME and DMC liquid streams, and formate is recovered through the formate aqueous solution liquid stream.

6. The method for treating alcohol ester byproducts in the production of ethylene glycol from syngas according to claim 5, characterized in that, Includes one or more of the following conditions: B1) In step 1), the alcohol ester byproduct stream is fed into the stirred tank reactor via the alcohol ester byproduct stream pipeline; B2) In step 1), the flow rate of the alcohol ester byproduct stream fed into the stirred tank reactor is 0.1-20 t / h; B3) In step 1), the mass ratio of the alcohol ester byproduct stream to the added alkali solution is 1:0.1-5; B4) In step 1), the alkali in the alkaline solution is selected from at least one of potassium hydroxide, sodium hydroxide, and calcium hydroxide; B5) In step 1), the alkaline solution is an aqueous solution of alkali, and the concentration of alkali in the alkaline solution is 25-50 wt%. B6) In step 1), the alkaline solution is fed into the stirred tank reactor via the alkaline solution input pipeline; B7) In step 1), the temperature of the reaction is 50-100°C; B8) In step 1), the pressure of the reaction is 0-2 MPaG; B9) In step 1), the pH of the reaction is 4-10; preferably, when the concentration of DMC in the alcohol ester byproduct stream is ≤1wt%, the pH of the reaction is 7-8; when the concentration of DMC in the alcohol ester byproduct stream is >1wt%, the pH of the reaction is ≥6 and <7. B10) In step 2), the reaction liquid is fed into the light component recovery tower through the first connecting pipeline under the action of the discharge pump; B11) In step 2), the operating conditions of the light component recovery tower are: pressure 0-1 MPa; Reflux ratio 1–30; top temperature 10–60℃; bottom temperature 100–180℃; B12) In step 2), the non-condensable gas stream is sequentially extracted from the non-condensable gas output pipeline at the top of the tower via a condenser; B13) In step 2), the liquid streams MN and MF are sequentially drawn out from the top liquid phase extraction pipeline of the tower through the condenser and reflux tank under the action of the reflux pump. B14) In step 2), the bottom of the light component recovery tower is heated by a reboiler; B15) In step 2), the formate aqueous solution liquid phase stream is extracted through the reboiler extraction pipeline under the action of the reboiler pump; B16) In step 2), the liquid phase of the formate aqueous solution is an aqueous solution of formate, and the aqueous solution of formate is dried in an evaporator to obtain solid formate; Preferably, the formate solution contains 50-75 wt% formate by mass percentage; And / or, in the formate solution, the concentration of carbonate is ≤0.2wt%; And / or, the drying temperature is 60-120°C; And / or, the drying time is 5-11 hours; And / or, the drying process is performed at least once; And / or, the formate is selected from at least one of potassium formate, sodium formate, and calcium formate.

7. An experimental method for treating alcohol ester byproducts in the production of ethylene glycol from syngas, using the experimental system for treating alcohol ester byproducts in the production of ethylene glycol from syngas as described in claim 3, comprising: The alcohol ester byproduct containing MF was added to a flask, then placed in an oil bath and stirred and heated. Alkali solution was then taken from the alkali tank and added to the flask for mixing and reaction. The flask was then removed and cooled to obtain the reaction solution.

8. The experimental method for treating alcohol ester byproducts in the production of ethylene glycol from syngas according to claim 7, characterized in that, Includes one or more of the following conditions: C1) The MF-containing alcohol ester byproduct includes at least MF; preferably, the MF-containing alcohol ester byproduct further includes at least one selected from DMC, ML, and ME; C2) The heating temperature is 60-65℃; The addition of the MF-containing alcohol ester byproduct described in C3) conforms to formula (1). The formula (1) is: (mass of alcohol ester byproduct containing MF × mass concentration of MF in alcohol ester byproduct containing MF / 60.05) / (mass of alkaline solution × mass concentration of alkali in alkaline solution / molecular weight of alkali) = 1: 0.9~1.

1. C4) The alkali in the alkaline solution is selected from at least one of potassium hydroxide, sodium hydroxide, and calcium hydroxide; C5) The alkaline solution is an aqueous solution of alkali, and the concentration of alkali in the alkaline solution is 25-50 wt%. The pH of the reaction described in C6) is 6-9; The reaction time described in C7) is 40-50 minutes; C8) describes cooling to room temperature.

9. A formate, obtained by the treatment of alcohol ester byproducts in the production of ethylene glycol from syngas as described in any one of claims 4-6 or the experimental treatment of alcohol ester byproducts in the production of ethylene glycol from syngas as described in any one of claims 7-8.

10. The use of the formate according to claim 9 in oil fields, in the production of potassium diformate, or as a hydrogen storage and production carrier.

Images