Production method for preparing calcium formate by using methyl formate and calcium carbonate as raw materials
Through the direct reaction of methyl formate with water and calcium carbonate and the simplified process steps, the problems of long process flow and high energy consumption in the existing calcium formate production technology are solved, and efficient and low-cost calcium formate production are achieved, and good market competitiveness and environmental benefits.
Patent Information
- Application Number
- CN202411514967.1
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-10-28
- Publication Date
- 2025-02-25
AI Technical Summary
The existing calcium formate production technology has problems such as long process flow, high energy consumption, high cost and high requirements for equipment materials.
The reaction of methyl formate with water and calcium carbonate at a certain temperature is adopted, and the calcium formate products are directly prepared through filtration, flash, evaporation and crystallization and drying, which simplifies the process route and reduces energy consumption and costs.
It realizes efficient and low-cost production of calcium formate, simple process, easy to produce continuously on a large scale, has strong market competitiveness, and can recycle and utilize waste liquid to reduce environmental pollution.
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Abstract
Description
Technical Field
[0001] The present application relates to a production method for preparing calcium formate from methyl formate and calcium carbonate as raw materials, belonging to the technical field of calcium formate production. Background Art
[0002] Calcium formate is also known as calcium formate, and its molecular formula is Ca(HCOO) 2 , slightly hygroscopic, slightly bitter, non-toxic, soluble in water. The aqueous solution is neutral. The solubility of calcium formate does not change much with increasing temperature. At present, the domestic calcium formate market is divided into two specifications: feed grade and industrial grade.
[0003] Calcium formate has a wide range of uses in feed, construction, leather and other fields: in animal husbandry, it can be used as a feed additive, suitable for all kinds of animals, which can increase and improve animal physique, enhance appetite, reduce diarrhea rate, and increase calcium absorption rate; in industry, it is also used in concrete, mortar additives, cement early strength agents, etc.
[0004] The mainstream industrial production technology of calcium formate at home and abroad is the neutralization method of calcium carbonate or calcium hydroxide, that is, calcium carbonate or calcium hydroxide and formic acid are neutralized to synthesize calcium formate. Since this technology uses formic acid as a raw material, it has the following obvious disadvantages: 1) High-purity formic acid needs to be obtained by hydrolysis and concentration of methyl formate, so the mainstream production technology involves multiple steps such as hydrolysis of methyl formate, concentration of formic acid, and preparation of calcium formate from calcium carbonate or calcium hydroxide, and the process cost is high; 2) The aqueous solution of formic acid is highly corrosive, and the reactor material requirements are high during the concentration process, and the equipment investment cost is high; 3) Formic acid and water are azeotropic, and the energy consumption is high during the concentration process. This method can meet the needs of calcium formate products for feed or chemical use, but it has the disadvantages of long process flow and high energy consumption. Summary of the invention
[0005] In order to solve the above problems existing in the prior art, the present invention provides a method for preparing calcium formate, which can be applied to large-scale calcium formate production. In this method, methyl formate, water and calcium carbonate are mixed and reacted in a certain proportion at a certain temperature, the calcium formate product and other substances are separated by filtering, and a feed grade or chemical grade product with a calcium formate content of more than 98% is finally obtained by flash evaporation, evaporation crystallization and drying. The method has a short process route, low energy consumption and low production cost; the process is simple, and it is easy to realize large-scale continuous production and has strong market competitiveness. Not only can it achieve huge economic and social benefits, but it can also achieve effective utilization of solid waste, which is beneficial to environmental protection.
[0006] The present application provides a production method for preparing calcium formate from methyl formate and calcium carbonate as raw materials. Most of the existing technologies use formic acid and calcium carbonate or calcium hydroxide to prepare feed-grade calcium formate, and the reaction route is longer, requiring at least three steps: hydrolysis of methyl formate to prepare formic acid, formic acid concentration, and reaction of formic acid with calcium carbonate to prepare calcium formate. The present method can realize the production of calcium formate directly from methyl formate and calcium carbonate in one step.
[0007] The process of the present invention is to use one reactor or multiple reactors connected in series or in parallel to achieve a calcium carbonate conversion rate of more than 99%. The calcium formate precipitate and its saturated solution are separated by filtering, and finally a feed-grade product with a calcium formate purity of more than 98% is obtained by flash evaporation, evaporation crystallization and drying.
[0008] The reaction principle is as follows:
[0009] 2H COOK 3 +H 2 O+CaCO 3 =Ca(HCOO) 2 +2CH 3 OH+CO 2 .
[0010] A production method for preparing calcium formate from methyl formate and calcium carbonate as raw materials, the production method comprising:
[0011] S1, injecting methyl formate, calcium carbonate and water into a reactor, reacting to obtain a reaction product;
[0012] S2, separating the reaction product into solid, liquid and gas to obtain calcium formate solid I, solution and gas;
[0013] S3, flashing and evaporating the solution to obtain calcium formate solid II;
[0014] The calcium formate solid I and the calcium formate solid II are dried to obtain a calcium formate product I and a calcium formate product II.
[0015] The present application can use waste liquid containing methyl formate and limestone as raw materials, and can utilize methyl formate waste liquid produced as a by-product in coal-to-ethylene glycol as raw material, or directly use limestone powder to produce calcium formate, and the production cost can be further reduced.
[0016] Optionally, the mass ratio of methyl formate to calcium carbonate is (1.1-5):1.
[0017] Preferably, the mass ratio of methyl formate to calcium carbonate is (1.1-1.5):1.
[0018] Optionally, the mass ratio of methyl formate to calcium carbonate is independently selected from any value among 1.1:1, 1.2:1, 1.5:1, 1.7:1, 2:1, 2.5:1, 3:1, 3.5:1, 4:1, 4.5:1, 5:1, or any range value therebetween.
[0019] Optionally, the mass ratio of water to methyl formate is (0.1-10):1.
[0020] Optionally, the mass ratio of water to methyl formate is independently selected from any value among 0.1:1, 0.2:1, 0.5:1, 0.7:1, 1:1, 2:1, 3:1, 4:1, 5:1, 6:1, 7:1, 8:1, 9:1, 10:1, or any range value therebetween.
[0021] Optionally, the reaction pressure is 0.2-20 MPa.
[0022] Preferably, the reaction pressure is 0.2-10 MPa.
[0023] Optionally, the reaction pressure is independently selected from any value among 0.2Mpa, 0.5Mpa, 1Mpa, 2Mpa, 3Mpa, 5Mpa, 8Mpa, 10Mpa, 12Mpa, 15Mpa, 17Mpa, 20Mpa, or any range between two values.
[0024] Optionally, the reaction temperature is 60-160°C.
[0025] Preferably, the reaction temperature is 80-130°C.
[0026] Optionally, the reaction temperature is independently selected from any value of 60°C, 70°C, 80°C, 90°C, 100°C, 110°C, 120°C, 130°C, 140°C, 150°C, 160°C or any range therebetween.
[0027] Optionally, the reaction time is 0.2 to 20 hours.
[0028] Preferably, the reaction time is 0.5 to 10 h.
[0029] Optionally, the reaction time is independently selected from any value among 0.2h, 0.3h, 0.5h, 0.7h, 1h, 2h, 5h, 7h, 10h, 12h, 15h, 17h, 20h, or any range therebetween.
[0030] Optionally, the reaction is carried out under stirring conditions, and the stirring rate is 5 to 500 rpm. A stirring paddle is arranged inside the reactor.
[0031] Optionally, in step S3, the gas phase product obtained by flash evaporation of the solution is passed through a separation system to recover methyl formate and methanol; and water is recovered by evaporative crystallization.
[0032] Optionally, in step S2, the obtained gas is used to recover the methyl formate and methanol carried out in the gas phase through a separation system, and the remaining gas is released.
[0033] Optionally, there are one or more reactors; wherein the multiple reactors are connected in series or in parallel.
[0034] Optionally, there are 2 reaction kettles.
[0035] Optionally, the drying temperature is 50-180°C.
[0036] The reaction temperature rises to a certain temperature, and the stirring is continued for a certain period of time to allow the reaction to proceed fully and the reaction product to be obtained after the reaction is completed; the reaction product is subjected to solid-liquid-gas separation to obtain calcium formate solid and calcium formate saturated solution; the calcium formate solid is dried to obtain a feed-grade calcium formate product; the calcium formate solution is subjected to flash evaporation, evaporation crystallization and drying to obtain a feed / chemical-grade calcium formate product. At the same time, methyl formate and water (including some formic acid) in the reaction liquid can be recovered, and methanol can be obtained. The gas part is recovered by the separation system. The methyl formate and methanol brought out of the gas phase part, and the remaining gas is relaxed. Methyl formate and water can be recycled, and methanol can be exported as a by-product, which can further improve the economic efficiency of the technology.
[0037] The beneficial effects of this application include:
[0038] The production method of preparing calcium formate from methyl formate and calcium carbonate provided in the present application: 1) the quality of the calcium formate product produced is stable, easy to control, the content can reach more than 98%, and the raw material conversion rate can reach more than 99%; 2) the preparation and separation process is simple and easy to realize continuous operation, and no other substances are introduced. The waste liquid in the separation process can be recycled and reused, and there is no solid waste and waste liquid discharge. It is easy to realize large-scale production and has strong market competitiveness; 3) the raw material can use the methyl formate waste liquid produced as a by-product in coal-to-ethylene glycol as a raw material, or directly use limestone powder, and the raw material cost can be further reduced; 4) compared with the traditional production process, the method has a short process route, avoiding the steps of hydrolyzing methyl formate to produce formic acid and formic acid concentration; and the reactor material requirements are low, ordinary 304 is sufficient. This method greatly simplifies the current production process of calcium formate, has low raw material cost, is easy to realize continuous production, is conducive to large-scale expansion, has low energy consumption, and has huge economic and social benefits. BRIEF DESCRIPTION OF THE DRAWINGS
[0039] Figure 1 A process flow chart provided for an embodiment of the present invention. DETAILED DESCRIPTION
[0040] The present application is described in detail below with reference to embodiments, but the present application is not limited to these embodiments.
[0041] Unless otherwise specified, the raw materials in the examples of this application were purchased through commercial channels.
[0042] Unless otherwise specified, conventional methods were used for testing and instrument settings were those recommended by the manufacturer.
[0043] In the embodiment, a single reactor is used and the material is ordinary 304.
[0044] like Figure 1 As shown, it is a process flow chart provided by an embodiment of the present invention.
[0045] Methyl formate, calcium carbonate and water enter the reactor to react and synthesize calcium formate, and then the reaction product is separated into solid, liquid and gas. The separated calcium formate solid is dried to obtain the calcium formate product and packaged. The separated solution is flashed and evaporated and crystallized in turn to obtain the calcium formate solid, which is then dried to obtain the calcium formate product and packaged. The separated gas is recovered by the separation system to recover the methyl formate and methanol brought out by the gas phase, and the remaining gas is released. The gas phase product obtained by flash evaporation can be separated by the separation system to recover methyl formate and methanol. Methyl formate enters the methyl formate storage tank for recycling, and methanol enters the methanol storage tank for export. The recovered water obtained by evaporation and crystallization can enter the reactor again for recycling.
[0046] Example 1
[0047] Feed grade calcium formate products A and B are produced according to the following method:
[0048] (1) Inject 120 L of water, 60 L of methyl formate (concentration>96%), and light calcium carbonate (CaCO 3 >99%) 45kg, start stirring (stirring speed 50rpm), and stir evenly.
[0049] (2) Start heating and maintain the reaction temperature at 90° C. for 8 hours. Maintain the reaction pressure below 4.0 MPa by controlling the release rate of the release gas.
[0050] (3) The calcium formate generated by the reaction is crystallized and precipitated at the bottom of the reactor. The stirring rate is 120 rpm and the stirring is continued for 30 min to allow the reaction to proceed fully. After the reaction is completed, the product is obtained. The gas part is directly released into the separation system, and the solid and solution are separated in the next step.
[0051] (4) The reaction product was sent to a centrifuge, and the centrifuge was turned on to separate the calcium formate solid and the solution at a centrifugal rate of 600 rpm to obtain solution A.
[0052] (5) The calcium formate solid is sent to a dryer and dried at 110° C. to obtain calcium formate solid particles A, wherein the calcium formate content can reach more than 98%.
[0053] (6) Solution A is subjected to flash evaporation and evaporative crystallization, and the solid after crystallization is dried to obtain calcium formate solid particles B, the content of which can also reach more than 98%. The gas phase obtained by flash evaporation of solution A passes through a separation system to recover methyl formate and obtain more than 98% methanol; the recycled water obtained by evaporative crystallization can be re-entered into the reactor for recycling. The vented gas in the reaction is recovered by a separation system to recover the methyl formate and methanol carried out by the gas phase, and the remaining gas is released.
[0054] (7) The various product indicators of feed-grade calcium formate products A and B were tested. The results are shown in Table 1.
[0055] Example 2
[0056] Feed grade calcium formate products C and D are produced according to the following method:
[0057] (1) Inject 100 L of water, 80 L of methyl formate (concentration>96%), and light calcium carbonate (CaCO 3 >99%) 45kg, start stirring (stirring speed 50rpm), and stir evenly.
[0058] (2) Start heating and maintain the reaction temperature at 130° C. for 6 hours. Maintain the reaction pressure below 1.6 MPa by controlling the release rate of the release gas.
[0059] (3) The calcium formate generated by the reaction is crystallized and precipitated at the bottom of the reactor. The stirring rate is 100 rpm and the stirring is continued for 30 minutes to allow the reaction to proceed fully. After the reaction is completed, the product is obtained. The gas part is directly released into the separation system, and the solid and solution are separated in the next step.
[0060] (4) The reaction product was sent to a centrifuge, and the centrifuge was turned on to separate the calcium formate solid and the solution at a centrifugal rate of 600 rpm to obtain solution A2.
[0061] (5) The calcium formate solid is sent to a dryer and dried at 130° C. to obtain calcium formate solid particles C, wherein the calcium formate content can reach more than 98%.
[0062] (6) Solution A2 is subjected to flash evaporation and evaporative crystallization, and the crystallized solid is dried to obtain calcium formate solid particles D, the content of which can also reach more than 98%. The gas phase obtained by flash evaporation of solution A2 passes through a separation system to recover methyl formate and more than 98% of methanol; water can be recovered by evaporative crystallization. The methyl formate and methanol carried out by the gas phase of the relaxation gas in the reaction are recovered by a separation system, and the remaining gas is relaxed.
[0063] (7) The various product indicators of feed-grade calcium formate products C and D were tested. The results are shown in Table 1.
[0064] Example 3
[0065] Calcium formate products E and F are produced according to the following method:
[0066] (1) Inject 100 L of water, 60 L of methyl formate (concentration>96%), limestone powder (CaCO 3 >90%) 50kg, start stirring (stirring speed 50rpm), and stir evenly.
[0067] (2) Start heating and maintain the reaction temperature at 130° C. for 6 hours. Maintain the reaction pressure below 1.6 MPa by controlling the release rate of the release gas.
[0068] (3) The calcium formate generated by the reaction is crystallized and precipitated at the bottom of the reactor. The stirring rate is 100 rpm and the stirring is continued for 30 minutes to allow the reaction to proceed fully. After the reaction is completed, the product is obtained. The gas part is directly released into the separation system, and the solid and solution are separated in the next step.
[0069] (4) The reaction product was sent to a centrifuge, and the centrifuge was turned on to separate the calcium formate solid and the solution at a centrifugal rate of 600 rpm to obtain solution A3.
[0070] (5) The calcium formate solid is sent to a dryer and dried at 120° C. to obtain calcium formate solid particles E.
[0071] (6) Solution A3 is evaporated and crystallized, and the crystallized solid is dried to obtain calcium formate solid particles F. The gas phase obtained by flash evaporation of solution A3 passes through a separation system to recover methyl formate and more than 98% of methanol; water can be recovered by evaporation and crystallization. The methyl formate and methanol carried out by the gas phase of the relaxation gas in the reaction are recovered by a separation system, and the remaining gas is relaxed.
[0072] (7) The various product indicators of feed-grade calcium formate products E and F were tested. The results are shown in Table 1.
[0073] Example 4
[0074] Furthermore, the above-mentioned solid calcium formate samples were determined according to the HG / T 5614-2019 industry standard, and the content of heavy metal lead and arsenic was measured simultaneously: it was found that samples A, B, C, and D, which were produced using industrial methyl formate and light calcium carbonate as raw materials, met the quality standards for feed-grade calcium formate. Samples of calcium formate produced using limestone powder and industrial methyl formate as raw materials can also obtain feed-grade calcium formate E by centrifugal drying. The calcium formate content in product F is slightly lower, which is caused by the large amount of impurities in the raw material limestone powder, and it is necessary to further develop a corresponding simple and low-cost separation method.
[0075]
[0076]
[0077] The above are only a few embodiments of the present application and do not constitute any form of limitation to the present application. Although the present application is disclosed as above with preferred embodiments, it is not intended to limit the present application. Any technician familiar with the profession, without departing from the scope of the technical solution of the present application, using the technical content disclosed above to make slight changes or modifications are equivalent to equivalent implementation cases and fall within the scope of the technical solution.
Claims
1. A method for preparing calcium formate from methyl formate and calcium carbonate as raw materials, characterized in that: The production method comprises: S1, injecting methyl formate, calcium carbonate and water into a reactor, reacting to obtain a reaction product; S2, separating the reaction product into solid, liquid and gas to obtain calcium formate solid I, solution and gas; S3, flashing and evaporating the solution to obtain calcium formate solid II; The calcium formate solid I and the calcium formate solid II are dried to obtain a calcium formate product I and a calcium formate product II.
2. The production method according to claim 1, characterized in that The mass ratio of methyl formate to calcium carbonate is (1.1-5):1; Preferably, the mass ratio of methyl formate to calcium carbonate is (1.1-1.5):
1.
3. The production method according to claim 1, characterized in that The mass ratio of water to methyl formate is (0.1-10):
1.
4. The production method according to claim 1, characterized in that The reaction pressure is 0.2-20 MPa; Preferably, the reaction pressure is 0.2-10 MPa.
5. The production method according to claim 1, characterized in that: The reaction temperature is 60-160°C; Preferably, the reaction temperature is 80-130°C.
6. The production method according to claim 1, characterized in that: The reaction time is 0.2 to 20 hours; Preferably, the reaction time is 0.5 to 10 h.
7. The production method according to claim 1, characterized in that: The reaction is carried out under stirring conditions with a stirring rate of 5 to 500 rpm.
8. The production method according to claim 1, characterized in that: In step S3, the gas phase product obtained by flash evaporation of the solution is passed through a separation system to recover methyl formate and methanol; and water is recovered by evaporative crystallization.
9. The production method according to claim 1, characterized in that: In step S2, the obtained gas is used to recover the methyl formate and methanol carried out in the gas phase through a separation system, and the remaining gas is released.
10. The production method according to claim 1, characterized in that: There are one or more reactors; wherein the multiple reactors are connected in series or in parallel.