CN-121623815-B - Catalyst for preparing coal quality modified asphalt at low temperature and preparation method thereof

Abstract

The application provides a catalyst for preparing coal-quality modified asphalt at a low temperature, which comprises an Fe 3 O 4 inner core, an SiO 2 coating layer and a porous carbon loading layer from inside to outside, wherein a solid acid catalyst is loaded on the porous carbon loading layer. A preparation method of the catalyst for preparing coal-based modified asphalt at low temperature comprises the following steps of preparing a magnetic Fe 3 O 4 inner core, coating SiO 2 on the surface of the Fe 3 O 4 inner core to form a SiO 2 isolation layer, etching the SiO 2 isolation layer by adopting HF, coating SiO 2 on the etched SiO 2 isolation layer again to form a SiO 2 coating layer, constructing a porous carbon loading layer on the surface of the SiO 2 coating layer to obtain a catalyst carrier, and loading SO 4 2‑ /ZrO 2 -TiO 2 active substances on the surface of the porous carbon loading layer to obtain the catalyst for preparing coal-based modified asphalt at low temperature. The preparation method of the catalyst for preparing coal quality modified asphalt at low temperature can remarkably improve the demagnetization problem in the preparation process of the catalyst by adopting HF acid to etch the SiO 2 coating.

Inventors

• GUO XIAOCHUAN
• AN WEIWEI
• GUAN JING
• QI HUI
• XU LEI
• CHEN JUNSHENG

Assignees

• 宁夏西泰煤化工有限公司

Dates

Publication Date

20260512

Application Date

20260203

Claims (6)

1. 1. The preparation method of the catalyst for preparing coal quality modified asphalt at low temperature is characterized by comprising the following steps: step 1, preparing a magnetic Fe 3 O 4 inner core; Step 2, coating SiO 2 on the surface of the Fe 3 O 4 core to form a SiO 2 isolation layer; Step 3, etching the SiO 2 isolation layer by adopting HF; Step 4, coating SiO 2 on the etched SiO 2 isolation layer again to form a SiO 2 coating layer; step 5, constructing a porous carbon load layer on the surface of the SiO 2 coating layer to obtain a catalyst carrier; And 6, loading a solid acid catalyst on the surface of the porous carbon loading layer to obtain the catalyst for preparing coal-based modified asphalt at a low temperature, wherein the solid acid catalyst is SO 4 2- /ZrO 2 -TiO 2 .
2. 2. The method for preparing the catalyst for preparing coal-quality modified asphalt at a low temperature according to claim 1, wherein in the step 3, the volume concentration of the HF acid solution is 0.5% -2%, the etching rate is 1-3 nm/min, and the temperature is 30-50 ℃.
3. 3. The method of preparing a catalyst for low temperature production of coal-modified asphalt of claim 1, wherein the coating rate of step 4 to coat SiO 2 again is smaller than that of step 2 to coat SiO 2 for the first time.
4. 4. The method for preparing the catalyst for preparing coal-based modified asphalt at low temperature as claimed in claim 1, wherein the step 5 of constructing the porous carbon supporting layer on the surface of the SiO 2 coating layer comprises the following steps: Step 51, preparing a precursor load, namely adding Fe 3 O 4 -SiO 2 core-shell particles coated with SiO 2 twice into a mixed solution of ethanol and water for ultrasonic dispersion, and then adding a carbon source and a silane coupling agent to enable the carbon source and the silane coupling agent to be condensed and coated on the surfaces of the Fe 3 O 4 -SiO 2 core-shell particles to obtain the precursor load; step 52, separating the precursor load and drying; And 53, carbonizing the precursor load to obtain the porous carbon load layer.
5. 5. The method for preparing the catalyst for preparing coal-quality modified asphalt at low temperature according to claim 1, wherein the method for preparing the catalyst for loading SO 4 2- /ZrO 2 -TiO 2 on the surface of the porous carbon loading layer comprises the following specific steps: step 61, preparing sol, namely adding glacial acetic acid into tetrabutyl titanate absolute ethyl alcohol, stirring, then adding a zirconium nitrate solution and a dispersing agent, and continuously stirring to obtain ZrO 2 -TiO 2 sol; Step 62, adding a catalyst carrier into ZrO 2 -TiO 2 sol, performing ultrasonic dispersion, and stirring and evaporating to dryness to obtain black powder; Step 63, heating the black powder to decompose the metal precursor into ZrO 2 -TiO 2 particles, and cooling to obtain a catalyst loaded with ZrO 2 -TiO 2 ; Step 64, adding a catalyst loaded with ZrO 2 -TiO 2 into sulfuric acid to fully react SO 4 2- with hydroxyl groups on the surface of ZrO 2 -TiO 2 ; Step 65, filtering and separating solid, washing with water, vacuum drying, and heating to obtain the catalyst loaded with SO 4 2- /ZrO 2 -TiO 2 .
6. 6. A catalyst for preparing coal-quality modified asphalt at low temperature is characterized by being prepared by the method of claim 1.

Description

Catalyst for preparing coal quality modified asphalt at low temperature and preparation method thereof Technical Field The application relates to the technical field of modified asphalt catalysts, in particular to a catalyst for preparing coal modified asphalt at a low temperature and a preparation method thereof. Background Both modified pitch and modified pitch can be used to prepare anode pastes. Wherein the modified asphalt is the combination of matrix asphalt and modifier through physical action. The chemical composition of the matrix asphalt is unchanged, and the macroscopic properties of the asphalt are changed only by the filling, plasticizing or elastic action of the modifier and the like. The temperature for preparing the modified asphalt is lower, generally lower than 250 ℃, and the heating time is shorter. The modified asphalt is a three-dimensional network structure with polycyclic aromatic hydrocarbon as a main body through aromatic ring polycondensation reaction, and aims to reduce the content of small molecular volatile components and improve the ratio of carbon residue precursors. The temperature is higher when preparing modified asphalt, generally above 400 ℃, and the heating time is longer, and the main process is polycondensation. The reaction temperature can be reduced by adding the catalyst, so that the energy consumption is reduced, and the production cost is further reduced. Currently, there are two broad classes of catalysts for upgrading asphalt. 1. Liquid acid catalyst The traditional catalytic modification process mostly adopts liquid acid, such as sulfuric acid and phosphoric acid, as a catalyst. Such catalysts promote cyclization and polycondensation of aromatic molecules in asphalt by providing acidic sites. However, liquid acids have problems such as serious equipment corrosion, difficult product separation, etc. 2. Solid acid catalyst Solid acid catalysts, such as acidic alumina and vanadium oxide, can alleviate corrosion problems, but have higher reaction temperature, and meanwhile, excessive polycondensation is easy to initiate, quinoline insoluble substances are generated, and the processability of downstream products is affected. A common problem with both liquid and solid acid catalysts is that after the reaction is complete, the catalyst is difficult to recycle and the retention in the bitumen can increase the bitumen ash. While the acidic component remains in the pitch and subsequently enters the anode paste. When the anode paste is used in the fields of electrolytic aluminum and the like, corrosion can be caused to related equipment. Disclosure of Invention In view of the above, the application provides a catalyst which is convenient to recycle and is used for preparing coal-quality modified asphalt at a low temperature. The application also provides a preparation method of the catalyst. The catalyst for preparing coal quality modified asphalt at low temperature comprises an Fe 3O4 inner core, an SiO 2 coating layer and a porous carbon loading layer from inside to outside, wherein the porous carbon loading layer is loaded with a solid acid catalyst. Preferably, the solid acid catalyst is SO 42-/ZrO2-TiO2. The preparation method of the catalyst for preparing coal quality modified asphalt at low temperature comprises the following steps: step 1, preparing a magnetic Fe 3O4 inner core; Step 2, coating SiO 2 on the surface of the Fe 3O4 core to form a SiO 2 isolation layer; Step 3, etching the SiO 2 isolation layer by adopting HF acid; Step 4, coating SiO 2 on the etched SiO 2 isolation layer again to form a SiO 2 coating layer; Step 5, constructing a porous carbon loading layer on the surface of the SiO 2 coating layer to form a catalyst carrier; And 6, loading SO 42-/ZrO2-TiO2 catalyst on the surface of the porous carbon loading layer to obtain the catalyst for preparing coal modified asphalt at low temperature. The application has the technical effects that the catalyst taking Fe 3O4 as the core can be recovered through magnetic force after the modified asphalt is prepared, so that the ash content in the modified asphalt is reduced, the catalyst cost of the modified asphalt is reduced, and meanwhile, the acid content in the asphalt is reduced, so that the corrosion is low. The catalyst for preparing coal modified asphalt at low temperature contains abundant pores and a large number of active sites, has remarkable catalytic effect, can effectively reduce the reaction temperature of the modified asphalt, reduces the production energy consumption, and can reduce the coking value of the modified asphalt and the content of quinoline insoluble matters. The preparation method of the catalyst for preparing coal quality modified asphalt at low temperature provided by the application can remarkably improve the demagnetization problem in the preparation process of the catalyst by adopting HF acid to etch the SiO 2 coating layer, so that the catalyst can be recovered through magn