Preparation method and application of tooth spherical catalyst carrier

Abstract

The invention relates to the technical field of carrier forming, and discloses a preparation method and application of a tooth spherical catalyst carrier, the preparation method comprises the following steps: (1) carrying out mixing kneading, rolling and tooth spherical forming on an alumina precursor, a mixing kneading liquid and lubricating powder to obtain a tooth spherical forming substance; wherein the lubricating powder comprises at least two of starch, talcum powder and sesbania powder; (2) drying the tooth-ball-shaped molded substance, so that the dry basis content of the dried product is 40-50 wt%; and (3) roasting the dried product. The preparation method can effectively avoid cracking of the tooth balls, and can effectively improve the production efficiency and the product quality of the tooth-ball-shaped catalyst carrier.

Description

Technical Field

[0001] The present invention relates to the technical field of carrier forming, and particularly relates to a preparation method and application of a tooth-shaped spherical catalyst carrier. Background Art

[0002] Tooth-shaped spherical catalysts have the advantages of high activity, large processing load, low initial reaction temperature, etc., and have been well applied industrially in the refining processes of gasoline and diesel with high sulfur and nitrogen, olefin, and gum contents. For example, CN103285842A discloses a tooth-shaped spherical alumina carrier, and by adding an anionic surfactant, the properties such as the bulk density, pore volume, crush strength, and pore size distribution of the carrier can be optimized. CN103160312A discloses an application of a tooth-shaped spherical fractionation oil hydrotreating catalyst. However, in the prior art, there is less research on the production process of tooth-shaped spherical catalyst carriers.

[0003] Compared with carriers of regular shapes, as a special-shaped carrier, the tooth-shaped spherical catalyst carrier is difficult to prepare. The production efficiency is greatly affected by raw material properties, raw material ratios, strip extrusion rates, etc., and there are also problems such as easy breakage and poor uniformity, and the yield rate is not ideal. Therefore, the production efficiency of existing tooth-shaped spherical catalysts is low. Summary of the Invention

[0004] The purpose of the present invention is to overcome the problems of low production efficiency and poor quality of tooth-shaped spherical catalyst carriers existing in the prior art, and to provide a preparation method and application of a tooth-shaped spherical catalyst carrier. This preparation method has the characteristics of high forming efficiency and high output of tooth-shaped spherical catalyst carriers.

[0005] To achieve the above purpose, on the one hand, the present invention provides a preparation method of a tooth-shaped spherical catalyst carrier, including:

[0006] (1) Kneading, rolling, and forming into tooth-shaped spheres an alumina precursor, a kneading liquid, and a lubricating powder to obtain a tooth-shaped spherical formed product;

[0007] Wherein, the lubricating powder includes at least two of starch, talcum powder, and sesbania powder;

[0008] (2) Drying the tooth-shaped spherical formed product so that the dry basis content of the dried product is 40 - 50 wt%;

[0009] (3) Roasting the dried product.

[0010] Preferably, the lubricating powder includes starch, talcum powder, and sesbania powder;

[0011] Preferably, the mass ratio of the alumina precursor, starch, talcum powder and sesbania powder on a dry basis is 1:(0.05 - 0.08):(0.02 - 0.04):(0.01 - 0.05), preferably 1:(0.055 - 0.075):(0.032 - 0.037):(0.02 - 0.03).

[0012] The second aspect of the present invention provides the application of the toothed spherical catalyst carrier prepared by the above preparation method in gasoline and / or diesel refining catalysts.

[0013] Through the above technical solutions, the present invention can effectively avoid the cracking of toothed balls by the specific composition of the lubricating powder and by strictly controlling the drying degree of the formed product, can effectively improve the production efficiency and product quality of the toothed spherical catalyst carrier, can increase the catalyst output per day by more than 37%, and is of great significance for reducing production costs. Detailed Embodiments

[0014] In the ranges disclosed herein, the endpoints and any values are not limited to the exact ranges or values, and these ranges or values should be understood to include values close to these ranges or values. For numerical ranges, the endpoint values of each range, between the endpoint values of each range, between the endpoint values of each range and individual point values, and between individual point values can be combined with each other to obtain one or more new numerical ranges, and these numerical ranges should be regarded as specifically disclosed herein.

[0015] The first aspect of the present invention provides a preparation method of a toothed spherical catalyst carrier, comprising:

[0016] (1) Kneading, rolling and forming toothed balls with the alumina precursor, kneading liquid and lubricating powder to obtain a toothed spherical formed product;

[0017] Wherein, the lubricating powder includes at least two of starch, talcum powder and sesbania powder;

[0018] (2) Drying the toothed spherical formed product so that the dry basis content of the dried product is 40 - 50 wt%;

[0019] (3) Roasting the dried product.

[0020] Compared with the carrier of regular shape, the toothed spherical catalyst carrier, as a special-shaped carrier, has certain difficulties in the preparation process. The production efficiency is greatly affected by the properties of raw materials, raw material ratio, strip discharging rate, etc. It is easy to be damaged and has poor uniformity during the forming process, resulting in an unsatisfactory yield rate. Therefore, the production efficiency of the existing toothed spherical catalysts is relatively low. The inventors of the present invention found in experiments that by the specific composition of the lubricating powder and by strictly controlling the drying degree of the formed product, the cracking of toothed balls can be effectively avoided and the forming efficiency of the toothed spherical catalyst carrier can be improved.

[0021] In the present invention, any two of starch, talcum powder and sesbania powder are used as lubricating powder, and combined with specific drying conditions, the production efficiency of the tooth-shaped spherical catalyst carrier can be improved and the product quality can be enhanced. For example, it can be starch and talcum powder, starch and sesbania powder, or talcum powder and sesbania powder. The present invention has a relatively wide selection range for the ratio of any two of them, which can be 1:10 - 10:1.

[0022] In order to further improve the production efficiency, according to some preferred embodiments of the present invention, the lubricating powder includes starch, talcum powder and sesbania powder.

[0023] Preferably, the mass ratio of the alumina precursor, starch, talcum powder and sesbania powder on a dry basis is 1:(0.05 - 0.08):(0.02 - 0.04):(0.01 - 0.05), preferably 1:(0.055 - 0.075):(0.032 - 0.037):(0.02 - 0.03). Adopting the above preferred embodiments is beneficial to further improve the forming efficiency and product quality.

[0024] In the present invention, the alumina precursor refers to any substance that can obtain alumina through calcination, which is well-known to those skilled in the art. For example, it can be pseudo-boehmite. The present invention also has no special limitation on the alumina content in the pseudo-boehmite. For example, based on the total amount of the alumina precursor, the alumina content can be 41 - 43 wt%.

[0025] The present invention has no special limitation on the composition of the kneading liquid, which can be any auxiliaries solution beneficial to kneading in the art and is well-known to those skilled in the art.

[0026] According to some preferred embodiments of the present invention, the kneading liquid includes water, an extrusion aid and / or peptizing agent. The present invention has a relatively wide selection range for the extrusion aid, which can be any auxiliaries beneficial to extrusion in the art. For example, it can be at least one of stearic acid, hydroxyethyl cellulose and polysorbate, preferably stearic acid.

[0027] The present invention also has no special limitation on the peptizing agent, and any substance that can be used for peptizing the alumina precursor in the art can be used in the present invention. Preferably, the peptizing agent is selected from organic acids and / or inorganic acids, preferably at least one of nitric acid, citric acid, acetic acid and tartaric acid, and more preferably nitric acid.

[0028] According to some particularly preferred embodiments of the present invention, the kneading liquid comprises water, an extrusion aid, and a peptizing agent. Among them, the mass ratio of the alumina precursor, extrusion aid, and peptizing agent on a dry basis is 1:(0.005 - 0.02):(0.03 - 0.04), preferably 1:(0.009 - 0.015):(0.035 - 0.039). By adopting the above preferred embodiments and in combination with specific lubricating powder and drying methods, the production efficiency and product quality of the tooth-shaped spherical catalyst carrier can be further improved.

[0029] The present invention has no special requirements for the amount of water in the kneading liquid, and it can be selected according to actual needs. Preferably, the amount of water is such that the total mass concentration of the extrusion aid and peptizing agent in the kneading liquid is 2 - 5 wt%.

[0030] In the present invention, there are no special limitations on the specific conditions of the kneading and rolling. It can be carried out in conventional kneading and rolling equipment in the art. To further improve the forming efficiency and product quality, preferably, the conditions of the kneading include: the kneading frequency is 30 - 40 Hz, and the kneading time is 20 - 30 min.

[0031] Preferably, the rolling frequency is 15 - 25 Hz, and the rolling time is 30 - 55 min.

[0032] Controlling the conditions of kneading and rolling within the above preferred ranges can further optimize the processing time, improve the forming efficiency and product quality.

[0033] According to the present invention, after the materials are kneaded and rolled, tooth ball forming can be carried out by conventional tooth ball production equipment in the art. The present invention has no special requirements for the forming conditions, and those skilled in the art can select according to actual application needs. For example, tooth ball forming can obtain tooth-shaped spherical formed products with a cross-sectional area of quadrilateral, pentagonal, or hexagonal.

[0034] In the present invention, by controlling the dry basis percentage of the dried product within the range of 40 - 50 wt% and then carrying out calcination, it is beneficial to improve the production efficiency, ensure the product quality, and avoid cracking. Preferably, the drying makes the dry basis content of the dried product be 43 - 49 wt%.

[0035] In the present invention, the dry basis content of the dried product refers to calcining the dried product at 600 °C for 180 min, and the percentage of the mass after calcination to the mass before calcination is recorded as the dry basis content.

[0036] The present invention does not particularly limit the specific conditions for the drying, as long as the above dry basis content is satisfied. According to some preferred embodiments of the present invention, the conditions for the drying include: the temperature is 70 - 80 °C, preferably 72 - 75 °C; the heating rate is 0.18 - 0.25 °C / min, preferably 0.2 - 0.23 °C / min; the drying time is 150 - 250 min, preferably 170 - 210 min. By adopting the above preferred embodiments, the uniformity of the drying can be further improved, and the generation of cracks in the tooth balls caused by too fast water evaporation can be avoided.

[0037] According to some preferred embodiments of the present invention, the roasting includes: subjecting the dried product to a primary roasting so that the volatilization amount of the lubricating powder is not less than 50 wt%, and then performing a secondary roasting. By adopting the above roasting method with gradient heating to control the volatilization amount of the lubricating powder is beneficial to improving the product quality and avoiding cracking. Preferably, the volatilization amount of the lubricating powder in the primary roasting is 50 - 55 wt%.

[0038] In the present invention, the volatilization amount of the lubricating powder is measured by the method of fluorescence analysis of ion content.

[0039] In a further preferred embodiment, the conditions for the primary roasting include: the temperature is 400 - 500 °C, preferably 420 - 450 °C; the heating rate is 0.6 - 0.7 °C / min, preferably 0.62 - 0.65 °C / min; the roasting time is 200 - 300 min, preferably 230 - 260 min.

[0040] Preferably, the conditions for the secondary roasting include: the temperature is 600 - 700 °C, preferably 630 - 650 °C; the heating rate is 0.8 - 0.9 °C / min, preferably 0.83 - 0.85 °C / min; the roasting time is 240 - 300 min, preferably 260 - 280 min.

[0041] Preferably, the secondary roasting is carried out in an air atmosphere. Relative to 267 g of the dried product, the ventilation volume for the secondary roasting is 0.1 - 0.12 m 3 / h. Controlling the air volume for the secondary roasting within the above preferred range is beneficial to ensuring the full roasting of the carrier and the full volatilization of the additives, thereby being beneficial to improving the quality of the tooth-shaped catalyst product.

[0042] According to a particularly preferred embodiment of the present invention, the preparation method includes:

[0043] (1) Kneading, rolling and forming tooth balls from the alumina precursor, the kneading liquid and the lubricating powder to obtain a tooth-shaped formed product;

[0044] Among them, the lubricating powder includes starch, talcum powder and sesbania powder, and the mass ratio of the alumina precursor, starch, talcum powder and sesbania powder based on dry basis is 1:(0.055 - 0.075):(0.032 - 0.037):(0.02 - 0.03);

[0045] (2) Dry the tooth-shaped spherical formed product so that the dry basis content of the dried product is 40 - 50 wt%.

[0046] (3) Conduct a first calcination on the dried product so that the volatilization amount of the lubricating powder is not less than 50 wt%, and then conduct a second calcination. Preferably, the conditions of the first calcination include: the temperature is 420 - 450 °C, the heating rate is 0.62 - 0.65 °C / min, and the calcination time is 230 - 260 min; preferably, the conditions of the second calcination include: the temperature is 630 - 650 °C, the heating rate is 0.83 - 0.85 °C / min, and the calcination time is 260 - 280 min.

[0047] The second aspect of the present invention provides the application of the tooth-shaped spherical catalyst carrier prepared by the above preparation method in gasoline and / or diesel refining catalysts.

[0048] The present invention will be described in detail below through examples.

[0049] In the following examples, unless otherwise specified, the raw materials used are all commercially purchased.

[0050] In the following examples and comparative examples, a qualified carrier refers to a carrier with a complete appearance and a strength not less than 35 N / particle. The strength of the carrier is obtained by testing with a ZQJ-III intelligent particle strength testing machine.

[0051] Example 1

[0052] (1) Mix pseudoboehmite (aluminum oxide content 66 wt%), kneading liquid and lubricating powder, knead at a kneading frequency of 35 Hz for 25 min, and then roll at a rolling frequency of 20 Hz for 35 min using a rolling device.

[0053] Among them, the kneading liquid includes water, nitric acid and stearic acid, and the mass ratio of pseudoboehmite, water, stearic acid and nitric acid based on dry basis is 1:1.6:0.009:0.035. The lubricating powder includes starch, talcum powder and sesbania powder, and the mass ratio of pseudoboehmite, starch, talcum powder and sesbania powder based on dry basis is 1:0.055:0.032:0.002. Then send the mixture into a tooth ball forming device for forming to obtain a tooth-shaped spherical formed product with a pentagonal cross-section.

[0054] (2) Heat the tooth-spherical shaped product at a heating rate of 0.18 °C / min to 72 °C and dry for 170 min. The dry basis content of the dried product is 43 wt%.

[0055] (3) Heat the dried product at a heating rate of 0.62 °C / min to 420 °C and calcine for 230 min to make the volatilization amount of the lubricating powder 50 wt%. Then heat it at a heating rate of 0.83 °C / min to 630 °C and calcine for 260 min. A tooth-spherical catalyst support is obtained.

[0056] Calculate that the yield of the qualified support is 96.7 wt% and the cracking rate is 3.3 wt%.

[0057] Example 2

[0058] (1) Mix pseudo-boehmite (aluminum oxide content 66 wt%), kneading liquid and lubricating powder, knead at a kneading frequency of 35 Hz for 25 min, and then roll at a rolling frequency of 20 Hz for 35 min using a rolling device.

[0059] Among them, the kneading liquid includes water, nitric acid and stearic acid. The mass ratio of pseudo-boehmite, water, stearic acid and nitric acid based on dry basis is 1:1.6:0.012:0.037. The lubricating powder includes starch, talcum powder and sesbania powder. The mass ratio of pseudo-boehmite, starch, talcum powder and sesbania powder based on dry basis is 1:0.065:0.035:0.025. Then send the mixture into a tooth ball forming device for forming to obtain a tooth-spherical shaped product with a pentagonal cross-section.

[0060] (2) Heat the tooth-spherical shaped product at a heating rate of 0.21 °C / min to 73.5 °C and dry for 185 min. The dry basis content of the dried product is 45 wt%.

[0061] (3) Heat the dried product at a heating rate of 0.63 °C / min to 435 °C and calcine for 240 min to make the volatilization amount of the lubricating powder 52 wt%. Then heat it at a heating rate of 0.84 °C / min to 640 °C and calcine for 270 min. A tooth-spherical catalyst support is obtained.

[0062] Calculate that the yield of the qualified support is 97.1 wt% and the cracking rate is 2.9 wt%.

[0063] Example 3

[0064] (1) Mix pseudo-boehmite (aluminum oxide content 66 wt%), kneading liquid and lubricating powder, knead at a kneading frequency of 35 Hz for 25 min, and then roll at a rolling frequency of 20 Hz for 35 min using a rolling device.

[0065] Among them, the kneading liquid includes water, nitric acid, and stearic acid. The mass ratio of pseudo-boehmite, water, stearic acid, and nitric acid based on dry basis is 1:1.6:0.015:0.039. The lubricating powder includes starch, talcum powder, and sesbania powder. The mass ratio of pseudo-boehmite, starch, talcum powder, and sesbania powder based on dry basis is 1:0.075:0.037:0.03. Then the mixture is sent into a tooth-ball forming device for forming to obtain a tooth-ball shaped formed product with a pentagonal cross-section.

[0066] (2) The tooth-ball shaped formed product is heated to 75 °C at a heating rate of 0.23 °C / min and dried for 210 min. The dry basis content of the dried product is 49 wt%.

[0067] (3) The dried product is heated to 450 °C at a heating rate of 0.65 °C / min and calcined for 260 min, so that the volatilization amount of the lubricating powder is 55 wt%. Then it is heated to 650 °C at a heating rate of 0.85 °C / min and calcined for 280 min. A tooth-ball shaped catalyst carrier is obtained.

[0068] The yield of qualified carriers is calculated to be 96.9 wt%, and the cracking rate is 3.1 wt%.

[0069] Example 4

[0070] According to the method of Example 1, the difference is that the lubricating powder includes starch and talcum powder. The mass ratio of pseudo-boehmite, starch, and talcum powder based on dry basis is 1:0.06:0.03. Then kneading, rolling, tooth-ball forming, and drying and calcining are carried out according to the same method to obtain a tooth-ball shaped catalyst carrier. The yield of qualified carriers is calculated to be 91.5 wt%, and the cracking rate is 8.5 wt%.

[0071] Example 5

[0072] According to the method of Example 1, the difference is that the amounts of starch, talcum powder, and sesbania powder are such that the mass ratio of pseudo-boehmite, starch, talcum powder, and sesbania powder based on dry basis is 1:0.05:0.02:0.01. Then kneading, rolling, tooth-ball forming, and drying and calcining are carried out according to the same method to obtain a tooth-ball shaped catalyst carrier. The yield of qualified carriers is calculated to be 92.0 wt%, and the cracking rate is 8.0 wt%.

[0073] Example 6

[0074] According to the method of Example 1, the difference is that in step (3), the dried product is heated to 700 °C at a heating rate of 0.9 °C / min and calcined for 300 min to obtain a tooth-ball shaped catalyst carrier. The yield of qualified carriers is calculated to be 91.1 wt%, and the cracking rate is 8.9 wt%.

[0075] Comparative Example 1

[0076] According to the method of Example 1, except that in step (2), the tooth-shaped spherical molding is heated to 90 °C at a heating rate of 0.3 °C / min and dried for 250 min, and the dry basis content of the dried product is 70 wt%. Then, the calcination described in step (3) is carried out. A tooth-shaped spherical catalyst support is obtained. The yield of qualified supports is calculated to be 86.2 wt%, and the cracking rate is 13.8 wt%.

[0077] Comparative Example 2

[0078] According to the method of Example 1, except that in step (1), no lubricating powder is added. The yield of qualified supports is calculated to be 81.2 wt%, and the cracking rate is 18.8 wt%.

[0079] It can be seen from the comparison of the above examples and comparative examples that in the examples of the present invention, through the specific composition of the lubricating powder and by strictly controlling the drying degree of the molding, the cracking of the tooth balls can be effectively avoided, the production efficiency and product quality of the tooth-shaped spherical catalyst support can be effectively improved, the yield of qualified supports can be increased, and the cracking rate can be effectively reduced.

[0080] The preferred embodiments of the present invention have been described in detail above. However, the present invention is not limited thereto. Within the scope of the technical concept of the present invention, various simple modifications can be made to the technical solutions of the present invention, including any other suitable combination of each technical feature. These simple modifications and combinations should also be regarded as the content disclosed by the present invention and fall within the protection scope of the present invention.

Claims

1. A preparation method of a toothed spherical catalyst support, comprising: (1) Kneading, rolling and toothed ball forming an alumina precursor, a kneading liquid and a lubricating powder to obtain a toothed spherical formed product; wherein, the lubricating powder comprises at least two of starch, talcum powder and sesbania powder; (2) Drying the toothed spherical formed product so that the dry basis content of the dried product is 40-50 wt%; (3) Roasting the dried product.

2. The preparation method according to claim 1, wherein, the lubricating powder comprises starch, talcum powder and sesbania powder; Preferably, the mass ratio of the alumina precursor, starch, talcum powder and sesbania powder based on dry basis is 1:(0.05-0.08):(0.02-0.04):(0.01-0.05), preferably 1:(0.055-0.075):(0.032-0.037):(0.02-0.03).

3. The preparation method according to claim 1 or 2, wherein, the kneading liquid comprises water, an extrusion aid and / or a peptizing agent; Preferably, the peptizing agent is selected from organic acids and / or inorganic acids, preferably at least one of nitric acid, citric acid, acetic acid and tartaric acid, more preferably nitric acid; Preferably, the extrusion aid is selected from at least one of stearic acid, hydroxyethyl cellulose and polysorbate, preferably stearic acid.

4. The preparation method according to claim 3, wherein, the mass ratio of the alumina precursor, extrusion aid and peptizing agent based on dry basis is 1:(0.005-0.02):(0.03-0.04), preferably 1:(0.009-0.015):(0.035-0.039).

5. The preparation method according to any one of claims 1-4, wherein, the conditions of the kneading include: the kneading frequency is 30-40 Hz, and the kneading time is 20-30 min; Preferably, the rolling frequency is 15-25 Hz, and the rolling time is 30-55 min.

6. The preparation method according to any one of claims 1-5, wherein, the toothed ball forming is carried out in a toothed ball production device, and a toothed spherical formed product with a cross-sectional area of a quadrilateral, a pentagon or a hexagon is obtained through toothed ball forming.

7. The preparation method according to any one of claims 1-6, wherein, the conditions of the drying include: the temperature is 70-80 °C, the heating rate is 0.18-0.25 °C / min, and the drying time is 150-250 min.

8. The preparation method according to any one of claims 1-7, wherein, the roasting includes: subjecting the dried product to a first roasting so that the volatilization amount of the lubricating powder is not less than 50 wt%, and then performing a second roasting; Preferably, the first roasting makes the volatilization amount of the lubricating powder be 50-55 wt%.

9. The preparation method according to claim 8, wherein, the conditions of the first roasting include: the temperature is 400-500 °C, the heating rate is 0.6-0.7 °C / min, and the roasting time is 200-300 min; Preferably, the conditions for the secondary calcination include: a temperature of 600-700 °C, a heating rate of 0.8-0.9 °C / min, and a calcination time of 240-300 min; Preferably, the secondary roasting is carried out in an air atmosphere. With respect to 267 g of the dried product, the ventilation volume for the secondary roasting is 0.1 - 0.12 m 3 / h.

10. Use of the toothed spherical catalyst support prepared by the preparation method according to any one of claims 1-9 in a gasoline and / or diesel refining catalyst.