CN116003143A - Preparation method for improving MgO-C brick performance by modified phenolic resin - Google Patents
Preparation method for improving MgO-C brick performance by modified phenolic resin Download PDFInfo
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- CN116003143A CN116003143A CN202211641841.1A CN202211641841A CN116003143A CN 116003143 A CN116003143 A CN 116003143A CN 202211641841 A CN202211641841 A CN 202211641841A CN 116003143 A CN116003143 A CN 116003143A
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- Prior art keywords
- phenolic resin
- modified phenolic
- mgo
- brick
- improving
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- KXGFMDJXCMQABM-UHFFFAOYSA-N 2-methoxy-6-methylphenol Chemical class [CH]OC1=CC=CC([CH])=C1O KXGFMDJXCMQABM-UHFFFAOYSA-N 0.000 title claims abstract description 55
- 239000011449 brick Substances 0.000 title claims abstract description 24
- 238000002360 preparation method Methods 0.000 title claims abstract description 9
- 239000005011 phenolic resin Substances 0.000 claims abstract description 27
- 229920001568 phenolic resin Polymers 0.000 claims abstract description 27
- 239000003054 catalyst Substances 0.000 claims abstract description 26
- 229910052723 transition metal Inorganic materials 0.000 claims abstract description 26
- 150000003624 transition metals Chemical class 0.000 claims abstract description 19
- 238000003756 stirring Methods 0.000 claims abstract description 18
- 229910001404 rare earth metal oxide Inorganic materials 0.000 claims abstract description 14
- CPLXHLVBOLITMK-UHFFFAOYSA-N Magnesium oxide Chemical compound [Mg]=O CPLXHLVBOLITMK-UHFFFAOYSA-N 0.000 claims description 18
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 claims description 15
- 239000000843 powder Substances 0.000 claims description 15
- 239000000463 material Substances 0.000 claims description 13
- 238000001035 drying Methods 0.000 claims description 12
- 238000000034 method Methods 0.000 claims description 12
- 239000000395 magnesium oxide Substances 0.000 claims description 9
- 238000002156 mixing Methods 0.000 claims description 9
- 239000000654 additive Substances 0.000 claims description 8
- 239000010439 graphite Substances 0.000 claims description 8
- 229910002804 graphite Inorganic materials 0.000 claims description 8
- 229910052759 nickel Inorganic materials 0.000 claims description 8
- 239000002245 particle Substances 0.000 claims description 8
- 238000000498 ball milling Methods 0.000 claims description 4
- 238000003825 pressing Methods 0.000 claims description 4
- 238000005303 weighing Methods 0.000 claims description 4
- 230000000996 additive effect Effects 0.000 claims description 3
- ISWSIDIOOBJBQZ-UHFFFAOYSA-N Phenol Chemical compound OC1=CC=CC=C1 ISWSIDIOOBJBQZ-UHFFFAOYSA-N 0.000 claims description 2
- 238000011068 loading method Methods 0.000 claims description 2
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 2
- 229910021193 La 2 O 3 Inorganic materials 0.000 claims 1
- 239000011819 refractory material Substances 0.000 abstract description 10
- 230000003197 catalytic effect Effects 0.000 abstract description 3
- 230000035939 shock Effects 0.000 abstract description 3
- 230000003628 erosive effect Effects 0.000 abstract description 2
- 239000002893 slag Substances 0.000 abstract description 2
- 239000000203 mixture Substances 0.000 description 4
- 239000000956 alloy Substances 0.000 description 3
- 229910045601 alloy Inorganic materials 0.000 description 3
- 239000011230 binding agent Substances 0.000 description 3
- 230000000694 effects Effects 0.000 description 3
- 230000009286 beneficial effect Effects 0.000 description 2
- 239000002041 carbon nanotube Substances 0.000 description 2
- 229910021393 carbon nanotube Inorganic materials 0.000 description 2
- 239000000835 fiber Substances 0.000 description 2
- 238000009472 formulation Methods 0.000 description 2
- 238000012986 modification Methods 0.000 description 2
- 230000004048 modification Effects 0.000 description 2
- 229910018134 Al-Mg Inorganic materials 0.000 description 1
- 229910018467 Al—Mg Inorganic materials 0.000 description 1
- ATJFFYVFTNAWJD-UHFFFAOYSA-N Tin Chemical compound [Sn] ATJFFYVFTNAWJD-UHFFFAOYSA-N 0.000 description 1
- 239000010426 asphalt Substances 0.000 description 1
- 239000007767 bonding agent Substances 0.000 description 1
- KGBXLFKZBHKPEV-UHFFFAOYSA-N boric acid Chemical compound OB(O)O KGBXLFKZBHKPEV-UHFFFAOYSA-N 0.000 description 1
- 239000004327 boric acid Substances 0.000 description 1
- 230000000052 comparative effect Effects 0.000 description 1
- 239000013078 crystal Substances 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 230000002708 enhancing effect Effects 0.000 description 1
- 229910021397 glassy carbon Inorganic materials 0.000 description 1
- 238000000227 grinding Methods 0.000 description 1
- 229910052751 metal Inorganic materials 0.000 description 1
- 239000002184 metal Substances 0.000 description 1
- 150000004767 nitrides Chemical class 0.000 description 1
- 239000002994 raw material Substances 0.000 description 1
- 229920005989 resin Polymers 0.000 description 1
- 239000011347 resin Substances 0.000 description 1
- 239000006104 solid solution Substances 0.000 description 1
- 238000009628 steelmaking Methods 0.000 description 1
Abstract
The invention relates to a preparation method for improving MgO-C brick performance by modified phenolic resin, which adds nano rare earth oxide into one or more transition metal elements to ball mill for a certain time, so that the rare earth oxide is dissolved in the transition metal elements to cause lattice distortion of the transition metal elements and improve self catalytic activity. And then adding the prepared catalyst into phenolic resin, and stirring to uniformly distribute the transition metal catalyst in the phenolic resin, so that the transition metal catalyst is fully contacted with the phenolic resin. Improves the slag erosion resistance, thermal shock resistance and high-temperature flexural strength of the MgO-C refractory material, and can greatly reduce the cost of the converter refractory material.
Description
Technical Field
The invention belongs to the technical field of metallurgical industry, and particularly relates to a preparation method for improving MgO-C brick performance by modified phenolic resin.
Background
The cost performance of high-temperature refractory materials used as inner liners in the steelmaking and ironmaking industries is more and more concerned, and pursuing low cost is the most concerned topic. There are various methods for reducing the cost of the refractory, such as optimizing the formulation of the refractory, selecting appropriate binders and additives, and the like. In recent years, the scholars have found that adding transition metals Ni, co, fe, or the like as catalysts to high temperature refractory materials can improve their performance, which is also one of the effective measures to reduce their price.
At present, phenolic resin is widely used as a bonding agent of MgO-C refractory material, and an amorphous glassy carbon structure is easy to generate at high temperature, and the structure is a brittle structure. The effect of adding transition metals Ni, fe or Co and the like into the refractory material is to catalyze phenolic resin to generate a crystal carbon structure, a carbon nano tube and a fiber carbon structure. The elastic modulus of the crystalline carbon structure is small, which is beneficial to enhancing the thermal shock resistance of the refractory material, and the carbon nano tube and the fiber carbon structure improve the toughness of the material through bridging or pulling out. Most of students directly add transition metal powder into refractory materials for mixing, so that phenolic resin and the transition metal powder are difficult to fully contact, and the catalytic activity of the transition metal powder is reduced. In addition, the catalytic activity of transition metal elements such as Ni, fe, co, etc. cannot satisfy the current demand.
Disclosure of Invention
The invention provides a preparation method for improving MgO-C brick performance by modified phenolic resin, which solves the defects of the prior art.
In order to solve the technical problems, the invention provides a preparation method for improving MgO-C brick performance by modified phenolic resin, which is characterized by comprising the following steps: the method comprises the following specific steps:
1) Catalyst: putting rare earth oxide powder smaller than 10nm and transition metal powder into a ball mill for ball milling for 50-80 h, wherein the mass ratio of the rare earth oxide to the transition metal is 4-8%;
2) Modified phenolic resin: loading phenolic resin into a charging bucket with a stirring device, starting a stirring button, then adding the prepared catalyst, and continuing stirring until the catalyst is uniformly distributed in the phenolic resin after the catalyst is added, so as to obtain modified phenolic resin, wherein the stirring time is 25-30 min;
3) Mixing: weighing fused magnesia particles with different particle sizes, flake graphite, additives and modified phenolic resin, and putting the materials into a mixer for mixing for 25-30 min;
4) And (3) pressure forming: and placing the mixed materials into a mold to be molded, and before pressurizing, ensuring that the edges of the materials are fully fed through raking and pressing. When the pressure is applied, the pressure of the pressurizing hammer is light and then heavy, and when the light weight hammer and the heavy weight hammer are alternated, the formed brick is ejected out by the lower die and is exhausted;
5) And (3) drying: and (3) drying the formed bricks in a drying kiln at 180 ℃ for 8 hours.
The beneficial effects are that: the invention uses nano rare earth oxide (La) 2 O 3 CeO or CeO 2 Etc.) are added into one or more transition metal elements (Ni, fe or Co, etc.), ball milling is carried out for a certain time, so that rare earth oxide is dissolved in the transition metal elements in a solid solution mode, the transition metal elements are caused to generate lattice distortion, and the self-catalytic activity of the rare earth oxide is improved.
Adding the prepared catalyst into phenolic resin, stirring to uniformly distribute the transition metal catalyst in the phenolic resin, and fully contacting the transition metal catalyst with the phenolic resin. Improves the slag erosion resistance, thermal shock resistance and high-temperature flexural strength of the MgO-C refractory material, and can greatly reduce the cost of the converter refractory material. When the alloy is used on a converter of a certain steelworks, the service life can reach 15000 furnaces, and compared with the original 11800 furnaces, the alloy is increased by about 3200 furnaces.
Detailed Description
To make the objects, contents and advantages of the present invention more apparent, the following detailed description of the specific embodiments of the present invention will be given.
The invention provides a preparation method for improving MgO-C brick performance by modified phenolic resin, which comprises the following main raw material physicochemical property indexes: mgO content in the fused magnesia is more than 97.3% (wt), caO is more than 1.2% (wt), siO 2 < 0.3% (wt) and Fe 2 O 3 < 0.6% (wt). The C content in the flake graphite is more than 97% (wt), and the granularity is less than 0.15 mu m. The water content of the phenolic resin is less than 3 percent (wt), and the free phenol is less than 1.2 percent (wt); the additive is mainly one or more of metal (Al, mg, ca and the like), alloy (Al-Mg, al-Ca, al-Si and the like), boride (B4C, mgB2, boric acid and the like), organic matters (resin powder and asphalt powder), carbide (SiC and TiC), nitride (AlN, tiN, beta-Si 3N4 and the like) or oxide (Na 2O, znO, tiO2 and the like); the preparation method comprises the following specific steps:
1) Catalyst: rare earth oxide (La) of less than 10nm 2 O 3 CeO and CeO 2 One or more) powder and one or more transition metal (Ni, fe or Co) powder are put into a ball mill with a certain ball-to-material ratio for ball milling for 50-80 h, and the mass ratio of rare earth oxide to transition metal is 4-8%;
2) Modified phenolic resin: a certain amount of phenolic resin is put into a charging bucket with a stirring device, a stirring button is started, then a prepared catalyst is slowly added, stirring is continued until the catalyst is uniformly distributed in the phenolic resin after the catalyst is added, the stirring time is 25-30 min, and the mass ratio of the catalyst to the phenolic resin is less than 10% (wt) and more than 0;
3) Mixing: weighing fused magnesia particles (5-3 mm,3-1mm, less than 200 meshes), scaly graphite, additives and modified phenolic resin with different particle sizes according to a certain proportion, and putting the mixture into a mixer for mixing for 25-30 min; wherein, the mass of the fused magnesia is about 70 to 85 percent (wt), the crystalline flake graphite is about 10 to 20 percent (wt), the modified phenolic resin is 3.5 to 4.5 percent (wt), and the additive is less than 10 percent and more than 0 (wt).
4) And (3) pressure forming: and placing the mixed materials into a mold to be molded, and before pressurizing, ensuring that the edges of the materials are fully fed through raking and pressing. When the pressure is applied, the pressure of the pressurizing hammer is light and then heavy, and when the light weight hammer and the heavy weight hammer are alternated, the formed brick is ejected out by the lower die and is exhausted;
5) And (3) drying: and (3) drying the formed bricks in a drying kiln at 180 ℃ for 8 hours.
Examples:
1) Three groups of phenolic resin and modified phenolic resin comparative tests are respectively carried out, and the specific formulas are as follows:
after the formulation is completed, the modified phenolic resin can be verified to greatly improve MgO-C performance by completing the work in the following order.
1) Catalyst: rare earth oxide (La) of less than 10nm 2 O 3 CeO and CeO 2 One or more) powder and one or more transition metal (Ni, fe or Co, etc.) powder are put into a ball mill with a certain ball-to-material ratio for grinding for 50-80 h, and the mass ratio of rare earth oxide to transition metal is 4-8%;
2) Modified phenolic resin: a certain amount of phenolic resin is put into a charging bucket with a stirring device, a stirring button is started, then a prepared catalyst is slowly added, stirring is continued until the catalyst is uniformly distributed in the phenolic resin after the catalyst is added, the stirring time is 25-30 min, and the mass ratio of the catalyst to the phenolic resin is less than 10% and more than 0 (wt);
3) Mixing: the method comprises the steps of weighing fused magnesia particles (5-3 mm,3-1mm, less than 200 meshes), scaly graphite, additives and phenolic resin/modified phenolic resin with different particle sizes according to a certain proportion, and putting the mixture into a mixer for mixing for 25-30 min;
4) And (3) pressure forming: and placing the mixed materials into a mold to be molded, and before pressurizing, ensuring that the edges of the materials are fully fed through raking and pressing. When the pressure is applied, the pressure of the pressurizing hammer is light and then heavy, and when the light weight hammer and the heavy weight hammer are alternated, the formed brick is ejected out by the lower die and is exhausted;
5) And (3) drying: and (3) drying the formed bricks in a drying kiln at 180 ℃ for 8 hours.
The invention can make the transition metal powder (Ni, fe or Co) fully contact with the phenolic resin binder and can improve the self-catalytic activity of the phenolic resin binder.
The foregoing is merely a preferred embodiment of the present invention, and it should be noted that modifications and variations could be made by those skilled in the art without departing from the technical principles of the present invention, and such modifications and variations should also be regarded as being within the scope of the invention.
Claims (9)
1. A preparation method for improving MgO-C brick performance by modified phenolic resin is characterized by comprising the following steps: the method comprises the following specific steps:
1) Catalyst: putting rare earth oxide powder smaller than 10nm and transition metal powder into a ball mill for ball milling for 50-80 h, wherein the mass ratio of the rare earth oxide to the transition metal is 4-8%;
2) Modified phenolic resin: loading phenolic resin into a charging bucket with a stirring device, starting a stirring button, then adding the prepared catalyst, and continuing stirring until the catalyst is uniformly distributed in the phenolic resin after the catalyst is added, so as to obtain modified phenolic resin, wherein the stirring time is 25-30 min;
3) Mixing: weighing fused magnesia particles with different particle sizes, flake graphite, additives and modified phenolic resin, and putting the materials into a mixer for mixing for 25-30 min;
4) And (3) pressure forming: and placing the mixed materials into a mold to be molded, and before pressurizing, ensuring that the edges of the materials are fully fed through raking and pressing. When the pressure is applied, the pressure of the pressurizing hammer is light and then heavy, and when the light weight hammer and the heavy weight hammer are alternated, the formed brick is ejected out by the lower die and is exhausted;
5) And (3) drying: and (3) drying the formed bricks in a drying kiln at 180 ℃ for 8 hours.
2. The method for preparing the modified phenolic resin for improving the performance of the MgO-C brick, which is characterized in that: the rare earth oxide is La 2 O 3 CeO and CeO 2 One or more of the following.
3. The method for preparing the modified phenolic resin for improving the performance of the MgO-C brick, which is characterized in that: the transition metal powder is Ni, fe or Co.
4. The method for preparing the modified phenolic resin for improving the performance of the MgO-C brick, which is characterized in that: the grain size of the fused magnesia grain is 5-3mm,3-1mm, less than 200 meshes.
5. The method for preparing the modified phenolic resin for improving the performance of the MgO-C brick, which is characterized in that: in the step 3), the mass of the fused magnesia is 70-85% (wt), the crystalline flake graphite is 10-20% (wt), the modified phenolic resin is 3.5-4.5% (wt), and the additive is less than 10% and more than 0 (wt).
6. The method for preparing the modified phenolic resin for improving the performance of the MgO-C brick, which is characterized in that: the C content in the flake graphite is more than 97% (wt), and the granularity is less than 0.15 mu m.
7. The method for preparing the modified phenolic resin for improving the performance of the MgO-C brick, which is characterized in that: the water content of the phenolic resin is less than 3% (wt), and the free phenol is less than 1.2% (wt).
8. The method for preparing the modified phenolic resin for improving the performance of the MgO-C brick, which is characterized in that: mgO content in the fused magnesia is more than 97.3% (wt), caO is more than 1.2% (wt), siO 2 < 0.3% (wt) and Fe 2 O 3 ＜0.6％(wt)。
9. The method for preparing the modified phenolic resin for improving the performance of the MgO-C brick, which is characterized in that: in step 2), the mass ratio of the catalyst to the phenolic resin is less than 10% and greater than 0.
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202211641841.1A CN116003143B (en) | 2022-12-20 | 2022-12-20 | Preparation method for improving MgO-C brick performance by modified phenolic resin |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202211641841.1A CN116003143B (en) | 2022-12-20 | 2022-12-20 | Preparation method for improving MgO-C brick performance by modified phenolic resin |
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| CN116003143A true CN116003143A (en) | 2023-04-25 |
| CN116003143B CN116003143B (en) | 2024-04-16 |
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| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP1462428A2 (en) * | 2003-03-28 | 2004-09-29 | Dowa Mining Co., Ltd. | Method of producing perovskite complex oxide and precursor substance used in the method |
| CN101245128A (en) * | 2008-03-13 | 2008-08-20 | 武汉科技大学 | Modified phenolic resin for fire resistive material and preparation method thereof |
| CN106518116A (en) * | 2016-11-25 | 2017-03-22 | 江西理工大学 | Special magnesium-carbon rare-earth brick for vanadium extracting furnace and manufacturing method for special magnesium-carbon rare-earth brick |
| CN107352977A (en) * | 2017-07-18 | 2017-11-17 | 海城市中兴高档镁质砖有限公司 | A kind of slag line brick for ladle and preparation method |
| CN112479684A (en) * | 2020-11-27 | 2021-03-12 | 云南濮耐昆钢高温材料有限公司 | Magnesium carbon brick for hot spot area of furnace wall of electric arc furnace |
| CN112897992A (en) * | 2021-01-29 | 2021-06-04 | 鞍山市和丰耐火材料有限公司 | High-temperature-treated magnesia carbon brick for RH dip pipe and circulating pipe and preparation method thereof |
| CN114773777A (en) * | 2022-05-26 | 2022-07-22 | 江西华伍制动器股份有限公司 | Preparation method of resin-based composite material added with rare earth oxide and nano silicon dioxide |
-
2022
- 2022-12-20 CN CN202211641841.1A patent/CN116003143B/en active Active
Patent Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP1462428A2 (en) * | 2003-03-28 | 2004-09-29 | Dowa Mining Co., Ltd. | Method of producing perovskite complex oxide and precursor substance used in the method |
| CN101245128A (en) * | 2008-03-13 | 2008-08-20 | 武汉科技大学 | Modified phenolic resin for fire resistive material and preparation method thereof |
| CN106518116A (en) * | 2016-11-25 | 2017-03-22 | 江西理工大学 | Special magnesium-carbon rare-earth brick for vanadium extracting furnace and manufacturing method for special magnesium-carbon rare-earth brick |
| CN107352977A (en) * | 2017-07-18 | 2017-11-17 | 海城市中兴高档镁质砖有限公司 | A kind of slag line brick for ladle and preparation method |
| CN112479684A (en) * | 2020-11-27 | 2021-03-12 | 云南濮耐昆钢高温材料有限公司 | Magnesium carbon brick for hot spot area of furnace wall of electric arc furnace |
| CN112897992A (en) * | 2021-01-29 | 2021-06-04 | 鞍山市和丰耐火材料有限公司 | High-temperature-treated magnesia carbon brick for RH dip pipe and circulating pipe and preparation method thereof |
| CN114773777A (en) * | 2022-05-26 | 2022-07-22 | 江西华伍制动器股份有限公司 | Preparation method of resin-based composite material added with rare earth oxide and nano silicon dioxide |
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| CN116003143B (en) | 2024-04-16 |
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