Catalyst for removing carbon monoxide from ethylene and propylene and preparation method thereof

Abstract

The invention relates to a catalyst for removing carbon monoxide from ethylene and propylene and a preparation method thereof, and relates to the technical field of catalysts, the catalyst for removing carbon monoxide from ethylene and propylene mainly comprises copper oxide, zinc oxide, alumina and a modification auxiliary agent, the modification additive is one or a mixture of two of compounds of metal elements in the IA family, the IIA family and the IVA family in the periodic table of elements. The preparation process of the catalyst is simple, the prepared catalyst is used for removing trace carbon monoxide in ethylene and propylene fluids, the volume fraction of carbon monoxide in ethylene and propylene can be reduced to 0.02 * 10 <-6 > or below from about 0.10 * 10 <-6 >, and the quality requirement of the propylene raw material for gas-phase polymerization is met. The catalyst can synchronously remove trace oxygen and sulfur, and has the advantages of favorable purification effect, low catalyst use quantity, long service life, high removal activity and favorable stability.

Description

Technical Field

[0001] The present invention relates to the technical field of catalysts, and in particular to a catalyst for removing carbon monoxide from ethylene and propylene and a preparation method thereof. Background Art

[0002] Carbon monoxide (CO) is a common, hazardous gas that poses serious risks to the environment and human health. Large quantities of CO are produced in many industrial processes, necessitating efficient catalysts for its removal. Non-precious copper-based catalysts are widely used for the removal of trace amounts of CO in industrial processes, particularly in industries requiring deep CO removal, such as the electronics and petrochemical polyolefin industries. These sectors have stringent requirements for CO content in feed streams, sometimes reaching levels in the ppb range, and copper oxide plays a key role in these processes. Compared to precious metal catalysts, copper oxide-based CO removal operates under relatively mild reaction conditions, requiring neither high temperatures nor high pressures, thus reducing equipment requirements and operating costs. For example, some copper oxide catalysts can effectively remove CO at relatively low temperatures. As a common metal oxide, copper oxide is widely available and relatively inexpensive, making copper oxide-based CO removal technologies economical and cost-effective compared to precious metal catalysts such as gold, palladium, and platinum.

[0003] At the same time, copper oxide catalysts also face many technical challenges, which are mainly reflected in the following aspects:

[0004] (1) Catalytic activity needs to be improved: The copper oxide catalyst prepared by the co-precipitation method in the existing technology is in the form of cylindrical particles. The copper oxide inside the particles actually only plays a supporting role and cannot catalyze the oxidation reaction with CO. As a result, only a small amount of copper oxide in the catalyst plays a catalytic role, and a large amount of copper oxide only plays a supporting role. The utilization rate of CuO is very low and the activity is generally not high.

[0005] (2) Insufficient stability: In actual applications, copper oxide catalysts may be affected by reaction conditions such as temperature, pressure, and atmosphere, causing changes in the structure and performance of the catalyst, thereby affecting its stability and service life. For example, under high temperature conditions, copper oxide may sinter, resulting in a reduction in the active sites of the catalyst, affecting its CO removal effect.

[0006] (3) Limited anti-poisoning ability: In some complex gas systems, there may be other impurities or pollutants that may interact with the copper oxide catalyst, causing catalyst poisoning and thus reducing its ability to remove CO. For example, in gases containing elements such as sulfur and chlorine, copper oxide catalysts are easily poisoned.

[0007] In the 1990s, the CuO / ZnO catalyst developed by Sinopec Beijing Research Institute of Chemical Industry was used to remove trace CO from gas-phase ethylene, with a content of less than or equal to 5×10 -6 (v / v) of CO removal to less than or equal to 1×10 -7 (v / v). The activity of polymerization catalysts has significantly increased, from the third generation to the fourth and fifth generations. This has also placed higher demands on CO removal catalysts, necessitating the development of more efficient CO removal catalysts and technologies at lower temperatures. Summary of the Invention

[0008] In order to solve the above problems, the present invention provides a catalyst for removing carbon monoxide from ethylene and propylene and a preparation method thereof.

[0009] In the first aspect, the present invention provides a catalyst for removing carbon monoxide from ethylene and propylene, wherein the main components of the catalyst for removing carbon monoxide from ethylene and propylene include copper oxide, zinc oxide, aluminum oxide and a modification aid, and the modification aid is a mixture of one or two of compounds of metal elements in Group IA, Group IIA and Group IV A of the periodic table.

[0010] Furthermore, in terms of weight percentage, the copper oxide content is 20% to 40%.

[0011] Furthermore, in terms of weight percentage, the zinc oxide content is 45% to 70%.

[0012] Furthermore, in terms of weight percentage, the aluminum oxide content is 0.1% to 6%.

[0013] Furthermore, the modification aid includes potassium oxide, magnesium oxide, calcium oxide and silicon oxide; in terms of weight percentage, the potassium oxide content is 0.2% to 0.6%; in terms of weight percentage, the magnesium oxide content is 0.1% to 5%; in terms of weight percentage, the calcium oxide content is 0.1% to 4%.

[0014] Furthermore, the catalyst for removing carbon monoxide from ethylene and propylene also includes graphite, and the content of the graphite is 1% to 3% by weight.

[0015] In a second aspect, the present invention provides a method for preparing the catalyst for removing carbon monoxide from ethylene or propylene according to any one of the first aspects, such as Figure 1 As shown, the preparation method comprises the following steps:

[0016] The salts of the metal components are prepared into a solution in proportion, and then precipitated with a precipitant and aged to obtain a first material;

[0017] Adding the modifying agent 1 to the first material, and performing beating, washing, and drying to obtain a filter cake;

[0018] After adding the modification aid 2 to the filter cake, the filter cake is subjected to grinding, granulation and drying to obtain granules;

[0019] The particles are calcined, graphite is added and the particles are pressed into tablets to obtain the catalyst for removing carbon monoxide from ethylene and propylene.

[0020] Furthermore, the precipitant is one of sodium carbonate, sodium bicarbonate, ammonium bicarbonate, ammonium carbonate or ammonia water, and the beating time is 25 to 30 minutes.

[0021] Furthermore, the calcination temperature is 300°C to 450°C, and the specific surface area of the catalyst is 40 to 70 m 2 / g.

[0022] Furthermore, the catalyst for removing carbon monoxide from ethylene and propylene is suitable for removing trace carbon monoxide from ethylene and propylene fluids, and reducing the volume fraction of carbon monoxide in refinery propylene from about 0.10×10 -6 reduced to 0.02×10 -6 The following meet the quality requirements of propylene raw materials for gas phase polymerization.

[0023] The above technical solution provided by the embodiment of the present invention has at least the following advantages compared with the prior art:

[0024] The embodiment of the present invention provides a catalyst for removing carbon monoxide from ethylene and propylene and a preparation method thereof. Compared with the prior art, the catalyst preparation process of the present invention is simple. The prepared catalyst is used to remove trace carbon monoxide from ethylene and propylene fluids, and can reduce the volume fraction of carbon monoxide in ethylene and propylene from about 0.10×10 -6 reduced to 0.02×10 -6 The following meet the quality requirements of propylene raw materials for gas phase polymerization. The catalyst can also remove trace oxygen and sulfur simultaneously, with good purification effect, low catalyst usage, long service life, high removal activity and excellent stability. Specifically:

[0025] (1) With the addition of additives with different structures, the active components are more evenly dispersed, the proportion of active components inside the particles is lower, the utilization rate of the active component Cu is significantly improved, and the catalyst has a good effect in removing trace CO from ethylene and propylene fluids.

[0026] (2) Adding metal additives can effectively promote the synergistic effect of metal carriers, inhibit their sintering and agglomeration during the reaction, reduce the loss of metal during the reaction, and enhance the stability of the catalyst. When the catalyst encounters changes in temperature, pressure, atmosphere, etc. during use, the structure and performance of the catalyst are not easily changed, and no sintering occurs. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the invention and, together with the description, serve to explain the principles of the invention.

[0028] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, for ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative labor.

[0029] Figure 1 The present invention provides a flow chart of a method for preparing a catalyst for removing carbon monoxide from ethylene and propylene. DETAILED DESCRIPTION

[0030] To make the objectives, technical solutions, and advantages of the embodiments of the present invention more clear, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts shall fall within the scope of protection of the present invention.

[0031] Unless otherwise specified, various raw materials, reagents, instruments and equipment used in the present invention can be purchased from the market or prepared by existing methods.

[0032] The technical solutions provided by the present invention are as follows:

[0033] A catalyst for removing carbon monoxide from ethylene and propylene fluids. The catalyst mainly contains copper oxide, zinc oxide, and aluminum oxide, and also contains a modification auxiliary agent. The modification auxiliary agent is one or a mixture of two compounds of metal elements such as potassium, sodium, magnesium, calcium, strontium, barium, and silicon in Group IA, Group IA, and Group IV A of the periodic table.

[0034] The mass composition of the catalyst includes: the mass composition of the catalyst includes: copper oxide is 20% to 40%, for example, 20%, 25%, 30%, 35%, 40% or a range consisting of any two thereof; zinc oxide is 45% to 70%, for example, 45%, 50%, 55%, 60%, 70% or a range consisting of any two thereof; aluminum oxide is 0.1% to 6%, for example, 0.1%, 1%, 2%, 4%, 6% or a range consisting of any two thereof; potassium oxide is 0.2% to 0.6%, for example, 0.2%, 0.3%, 0.4%, 0.5% %, 0.6% or a range consisting of any two thereof; magnesium oxide is 0.1% to 5%, for example, 0.1%, 1%, 2%, 3%, 5% or a range consisting of any two thereof; calcium oxide is 0.1% to 4%, for example, 0.1%, 1%, 2%, 3%, 4% or a range consisting of any two thereof; graphite is 1% to 3%, for example, 1%, 1.5%, 2%, 2.5%, 3% or a range consisting of any two thereof; silicon oxide is 0.1% to 10%, for example, 0.1%, 1%, 3%, 6%, 10% or a range consisting of any two thereof.

[0035] The preparation method of the catalyst includes the following preparation steps: (1) preparing a solution of the salts of each metal component in proportion; (2) aging the solution after precipitation with a precipitant; (3) adding a modification agent 1 to the aged material, beating, washing, and drying the material to obtain a dry filter cake; (4) adding a modification agent 2 to the filter cake, grinding, granulating, and drying the filter cake; (5) calcining the dried particles, adding graphite, and pressing the dried particles into tablets to prepare a catalyst sample. The precipitant in step (2) is one of sodium carbonate, sodium bicarbonate, ammonium bicarbonate, ammonium carbonate, or ammonia water. The precipitation temperature in step (2) is 60°C to 70°C, and the pH value at the precipitation end point is 7.5 to 8.0. The beating time in step (3) is 25 to 30 minutes. The calcination temperature in step (5) is 300°C to 450°C. The specific surface area of the catalyst is 40 to 70 m 2 / g.

[0036] The catalyst of the present invention is mainly used to remove trace carbon monoxide in ethylene and propylene fluids, and can reduce the volume fraction of carbon monoxide in refinery propylene from about 0.10×10 -6 reduced to 0.02×10 -6 The following meet the quality requirements of propylene raw materials for gas phase polymerization.

[0037] The present invention will be further described below in conjunction with specific examples. It should be understood that these examples are intended to illustrate the present invention only and are not intended to limit the scope of the invention. The experimental methods in the following examples where specific conditions are not specified are generally measured in accordance with national standards. If there are no corresponding national standards, then the methods are carried out in accordance with general international standards, conventional conditions, or the conditions recommended by the manufacturer.

[0038] Example 1

[0039] 500 ml of 1.0 M copper nitrate solution, 1710 ml of 1.0 M zinc nitrate solution, and 2 ml of 1.0 M aluminum nitrate solution were prepared into a mixed solution, and the mixed solution was co-precipitated with a sodium carbonate solution in a stirred precipitation tank. The precipitation temperature was controlled at 65-70 ° C, and the precipitation end point pH value was 7.5. Then, the solution was aged at 70-75 ° C for 30 minutes. After aging, 0.8 g of potassium hydroxide, 0.5 g of magnesium hydroxide, and 1.0 L of silica sol were added to the solution, and the solution was beaten for 25 minutes. After washing and drying, 1.0 g of calcium carbonate and an appropriate amount of water were added to grind the material. After granulation and drying, it was calcined at 350 ° C, an appropriate amount of water and graphite were added, and finally it was pressed into Φ5.0 mm × (4-5) mm cylindrical tablets to obtain catalyst DC1.

[0040] Example 2

[0041] Take 500ml of 1.0M copper nitrate solution, 1173ml of 1.0M zinc nitrate solution, 16ml of 1.0M aluminum nitrate solution, and 40ml of 1.0M calcium nitrate solution to prepare a mixed solution, and co-precipitate the mixed solution with sodium carbonate solution in a stirred precipitation tank. The precipitation temperature is controlled at 65-70℃, and the precipitation end point pH value is 7.5. Then, age at 70℃-75℃ for 30min. After aging, 0.6g potassium hydroxide and 1.2L silica sol are added to the solution, and the solution is beaten for 25min. After washing and drying, 1.2g calcium carbonate and an appropriate amount of water are added to grind the material. After granulation and drying, calcination at 350℃, an appropriate amount of water and graphite are added, and finally the material is pressed into Φ5.0mm×(4-5)mm cylindrical tablets to obtain catalyst DC2.

[0042] Example 3

[0043] A mixed solution was prepared by taking 500 ml of 1.0 M copper nitrate solution, 896 ml of 1.0 M zinc nitrate solution, 26 ml of 1.0 M aluminum nitrate solution, and 40 g of JN-25 silica sol. The mixed solution was co-precipitated with a sodium carbonate solution in a stirred precipitation tank. The precipitation temperature was controlled at 65-70 ° C, and the precipitation end point pH value was 7.5. Then, the solution was aged at 70-75 ° C for 30 min. After aging, 0.8 g of magnesium hydroxide and 1.0 L of silica sol were added to the solution, and the solution was beaten for 25 min. After washing and drying, 1.0 g of calcium carbonate and an appropriate amount of water were added for grinding. After granulation and drying, the solution was calcined at 350 ° C, an appropriate amount of water and graphite were added, and the tablets were finally pressed into Φ5.0 mm × (4-5) mm cylindrical tablets to obtain catalyst DC3.

[0044] Example 4

[0045] Take 500ml of 1.0M copper nitrate solution, 698ml of 1.0M zinc nitrate solution, 45ml of 1.0M aluminum nitrate solution, and 50ml of 1.0M magnesium nitrate solution to prepare a mixed solution, and co-precipitate the mixed solution with sodium carbonate solution in a stirred precipitation tank. The precipitation temperature is controlled at 65-70℃, and the precipitation end point pH value is 7.6. Then, age at 70℃-75℃ for 30min. After aging, 0.8g potassium hydroxide and 1.0L silica sol are added to the solution, and the solution is beaten for 25min. After washing and drying, 1.0g calcium carbonate and an appropriate amount of water are added to grind the material. After granulation and drying, calcination at 350℃, an appropriate amount of water and graphite are added, and finally the material is pressed into Φ5.0mm×(4-5)mm cylindrical tablets to obtain catalyst DC4.

[0046] Example 5

[0047] 500 ml of 1.0 M copper nitrate solution, 550 ml of 1.0 M zinc nitrate solution, and 58 ml of 1.0 M aluminum nitrate solution were prepared into a mixed solution, and the mixed solution was co-precipitated with a sodium carbonate solution in a stirred precipitation tank. The precipitation temperature was controlled at 65-70 ° C, and the precipitation end point pH value was 7.7. Then, the solution was aged at 70-75 ° C for 30 minutes. After aging, 0.8 g of magnesium hydroxide and 1.0 L of silica sol were added to the solution, and the solution was beaten for 25 minutes. After washing and drying, 1.2 g of calcium carbonate and an appropriate amount of water were added for grinding. After granulation and drying, it was calcined at 350 ° C, an appropriate amount of water and graphite were added, and finally it was pressed into Φ5.0 mm × (4-5) mm cylindrical tablets to obtain catalyst DC5.

[0048] Comparative Example 1

[0049] Similar to Example 3, except that sodium bicarbonate was used as the precipitant, the precipitation temperature was controlled at 30°C to 40°C, the pH value at the precipitation endpoint was 6.5, the calcination temperature was 300°C, and the tablets were pressed into Φ5×5 cylindrical tablets to finally obtain catalyst DDC1.

[0050] Comparative Example 2

[0051] Similar to Example 3, except that ammonium bicarbonate was used as the precipitant, the precipitation temperature was controlled at 40°C to 50°C, the pH value at the precipitation endpoint was 7.0, the calcination temperature was 350°C, and the tablets were pressed into Φ6×5.5 cylindrical tablets to finally obtain catalyst DDC2.

[0052] Comparative Example 3

[0053] Similar to Example 3, except that ammonium carbonate was used as the precipitant, the precipitation temperature was controlled at 50°C to 60°C, the pH value at the precipitation endpoint was 7.5, the calcination temperature was 400°C, and the tablets were pressed into Φ6×6.5 cylindrical tablets to finally obtain catalyst DDC3.

[0054] Comparative Example 4

[0055] Similar to Example 3, except that ammonia water was used as the precipitant, the precipitation temperature was controlled at 70°C to 80°C, the pH value at the precipitation endpoint was 8.0, the calcination temperature was 450°C, and the tablets were pressed into Φ5.5×6.5 cylindrical tablets to finally obtain catalyst DDC4.

[0056] Comparative Example 5

[0057] Similar to Example 3, the only difference is that sodium bicarbonate is used as the precipitant, and the catalyst DDC5 is finally obtained.

[0058] Test Case

[0059] The catalysts DC1, DC2, DC3, DC4, and DC5 prepared in Example 1, Example 2, Example 3, Example 4, and Example 5 and Comparative Example 1, Comparative Example 2, Comparative Example 3, Comparative Example 4, and Comparative Example 5 were subjected to physical and chemical characterization, and tested on a single-tube fixed-bed reactor detection device. The test conditions were: pressure 0.10-0.20 MPa, reaction starting temperature 150°C ± 5°C, ethylene and propylene liquid space velocity 0.36h -1 , trace oxygen is (0.050~0.130)×10 -6 (v / v), and the reaction products were analyzed. The results are shown in the following table:

[0060] See Table 1 below for specific data.

[0061] Table 1 Comparison of catalyst performance between examples and comparative examples

[0062]

[0063]

[0064] From the data in Table 1, it can be seen that the catalyst prepared by this method has good performance in removing trace carbon monoxide from ethylene and propylene fluids, and can reduce the volume fraction of carbon monoxide in propylene from about 0.10×10 -6 reduced to 0.012×10 -6 The removal effect of the comparison catalyst is relatively poor. Under the same raw material conditions, the best removal effect is also at 0.022×10 -6 above.

[0065] Table 2 Comparison of catalyst performance between examples and comparative examples

[0066]

[0067] It can be seen from the data in Table 2 that the catalyst prepared by this method has a good effect of removing trace oxygen and sulfur while removing CO.

[0068] After the catalyst was used, the sample prepared by the present invention showed no sintering phenomenon after being unloaded, while DDC3 and DDC4 showed varying degrees of sintering.

[0069] Various embodiments of the present invention may be presented in the form of a range; it should be understood that the description in a range format is only for convenience and brevity and should not be construed as an inflexible limitation on the scope of the invention; therefore, the range description should be considered to have specifically disclosed all possible subranges and single numerical values within the range. For example, the description of a range from 1 to 6 should be considered to have specifically disclosed subranges such as from 1 to 3, from 1 to 4, from 1 to 5, from 2 to 4, from 2 to 6, from 3 to 6, etc., as well as single numbers within the range, such as 1, 2, 3, 4, 5, and 6, regardless of the range. In addition, whenever a numerical range is indicated herein, it is intended to include any cited numeral (fractional or integer) within the indicated range.

[0070] The foregoing description is intended only to provide specific embodiments of the present invention, which will enable those skilled in the art to understand and implement the present invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention is not intended to be limited to the embodiments shown herein, but is intended to be accorded the widest scope consistent with the principles and novel features claimed herein.

Claims

1. A catalyst for removing carbon monoxide from ethylene and propylene, characterized in that: The catalyst for removing carbon monoxide from ethylene and propylene mainly comprises copper oxide, zinc oxide, aluminum oxide and a modification aid, wherein the modification aid is a mixture of one or two compounds of metal elements in Group IA, Group IA and Group IV A of the periodic table.

2. The catalyst for removing carbon monoxide from ethylene and propylene according to claim 1, characterized in that: Calculated in weight percentage, the copper oxide content is 20% to 40%.

3. The catalyst for removing carbon monoxide from ethylene and propylene according to claim 1, characterized in that Calculated in weight percentage, the zinc oxide content is 45% to 70%.

4. The catalyst for removing carbon monoxide from ethylene and propylene according to claim 1, characterized in that In terms of weight percentage, the aluminum oxide content is 0.1% to 6%.

5. The catalyst for removing carbon monoxide from ethylene and propylene according to claim 1, characterized in that The modification aid comprises potassium oxide, magnesium oxide, calcium oxide and silicon oxide; in terms of weight percentage, the potassium oxide content is 0.2% to 0.6%; in terms of weight percentage, the magnesium oxide content is 0.1% to 5%; in terms of weight percentage, the calcium oxide content is 0.1% to 4%.

6. The catalyst for removing carbon monoxide from ethylene and propylene according to any one of claims 1 to 5, characterized in that The catalyst for removing carbon monoxide from ethylene and propylene also includes graphite. The content of the graphite is 1% to 3% by weight.

7. A method for preparing a catalyst for removing carbon monoxide from ethylene or propylene according to any one of claims 1 to 6, characterized in that: The preparation method comprises the following steps: The salts of the metal components are prepared into a solution in proportion, and then precipitated with a precipitant and aged to obtain a first material; Adding the modifying agent 1 to the first material, and performing beating, washing, and drying to obtain a filter cake; After adding the modification aid 2 to the filter cake, the filter cake is subjected to grinding, granulation and drying to obtain granules; The particles are calcined, graphite is added and the particles are pressed into tablets to obtain the catalyst for removing carbon monoxide from ethylene and propylene.

8. The method for preparing a catalyst for removing carbon monoxide from ethylene and propylene according to claim 7, characterized in that: The precipitant is one of sodium carbonate, sodium bicarbonate, ammonium bicarbonate, ammonium carbonate or ammonia water, and the beating time is 25 to 30 minutes.

9. The method for preparing a catalyst for removing carbon monoxide from ethylene and propylene according to claim 7, characterized in that: The calcination temperature is 300℃~450℃, and the specific surface area of the catalyst is 40~70m 2 / g.

10. The method for preparing a catalyst for removing carbon monoxide from ethylene and propylene according to claim 7, characterized in that: The catalyst for removing carbon monoxide from ethylene and propylene is suitable for removing trace carbon monoxide from ethylene and propylene fluids, and reducing the volume fraction of carbon monoxide in refinery propylene from about 0.10×10 -6 reduced to 0.02×10 -6 The following meet the quality requirements of propylene raw materials for gas phase polymerization.

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