Method for preparing composite white carbon black through calcium-adding solid-phase wet grinding of aluminic acid residues extracted by sulfuric acid method

Abstract

The invention relates to the technical field of chemical materials, in particular to a method for preparing composite white carbon black by calcium-adding solid-phase wet milling of sulfuric-acid-process extracted aluminate sludge, which comprises the following steps: mixing a sulfuric-acid-process extracted aluminate sludge wet sample and calcium mineral or chemical raw materials containing CaO according to the ratio of residual acid H2SO4: CaO = 1: (1-3), carrying out solid-phase wet milling reaction, and carrying out solid-phase wet milling to obtain the composite white carbon black. Drying the obtained mixed slurry to obtain composite white carbon black powder; the method comprises the following steps: carrying out composite wet grinding on the spent acid-containing aluminic acid extraction sludge and a calcium-containing substance in a ball mill, reacting the calcium-containing substance with sulfuric acid in the acid sludge to generate calcium sulfate hemihydrate, coating the surfaces of precipitated silicon dioxide particles with the calcium sulfate hemihydrate, and further growing into crystal whiskers to form the fibrous composite material. The invention further provides a manufacturing method of the composite white carbon black doped rubber, the fibrous composite white carbon black material can realize a mechanical enhancement effect, the surface property is adjustable, and the compatibility with a polymer rubber substrate material is better.

Description

Technical Field

[0001] The invention relates to a method for treating hazardous waste of aluminate slag extracted by sulfuric acid method, and in particular to a method for preparing composite white carbon black material by solid phase wet grinding reaction of aluminate slag extracted by sulfuric acid method and application thereof, belonging to the technical field of chemical materials. Background Art

[0002] Aluminum-containing minerals or solid wastes such as bauxite, kaolin, ball clay, coal gangue, and fly ash can be used as raw materials for aluminum extraction. Aluminum salts are obtained through acid dissolution, and then chemical reactions such as precipitation are used to prepare Al2O3 or other aluminum products. However, the acid residue after aluminum extraction is a type of solid hazardous waste. The filter residue is mainly amorphous silicon dioxide, called "silicon residue" or "acid residue", which contains a large amount of water and residual sulfuric acid. The traditional treatment method is to obtain siliceous powder through water washing, filtering, and drying. This method uses extremely high water consumption and high energy consumption, and the wastewater needs secondary treatment. The process is complicated, so this type of hazardous waste urgently needs new technology to be treated.

[0003] Taking ball clay as an example of aluminum extraction raw material, the mineral composition of ball clay is mainly composed of disordered kaolinite and quartz. It can be dissolved by acid, such as sulfuric acid (H2SO4), to destroy the Al-O octahedron of kaolinite to form a soluble aluminum sulfate solution. After filtration, the filtrate can be processed into polyaluminum sulfate flocculant or other aluminum products. The subsequent difficulty of this type of aluminum extraction technology is that after the acid dissolution of aluminum, a large amount of siliceous residue, that is, precipitated silica, will be produced, but the pH of this colloidal substance is about 1 to 2, it is strongly acidic, and the water content is relatively large (>50%, wt.), which is a typical type of hazardous waste. In order to further utilize this type of aluminum-extracting solid waste, traditional processes such as washing, filtering, drying, and calcining can be used to prepare white carbon black products. However, due to the high water and acid content of the "acid slag", the traditional method of producing white carbon black consumes a lot of material and energy. In addition, the white carbon black products are inferior to the white carbon black obtained by the gas phase method or the white carbon black products obtained by the water glass precipitation method in terms of color, particle size, specific surface area, oil absorption value, etc., and cannot be used in downstream products. In addition, there are the following difficulties in the process: (1) In order to wash away the residual acid, 4-5 times the mass of water is required, resulting in a large amount of acid-containing wastewater being discharged, forming secondary pollution; (2) The aluminate slag is in a colloidal state with a fine particle size, which is difficult to filter and consumes a lot of energy. In addition, the filter cloth and other filtering equipment need to be acid-resistant, and the equipment requirements are stringent; (3) In order to prepare silica powder, the filter cake after water washing and filtration needs to be dried. Because it has an extremely high water content, the energy consumption required for evaporation is further increased; (4) The conventional drying process causes the colloidal particles to agglomerate, and it is impossible to obtain silica powder with a smaller particle size, which is above 12 μm; (5) The conventional method (Announcement No. CN103420386A) obtains spherical silica, which cannot achieve the preparation of special-shaped silica particles. Therefore, it is difficult to maximize the strengthening and toughening properties of downstream products such as rubber and plastics. In view of this, it has become an urgent technology to develop the efficient use of sulfuric acid method to extract aluminate slag, digest wet slag solid waste, avoid complicated washing, filtering and drying processes, and obtain heterogeneous or fibrous precipitated silica materials.

[0004] Patents CN103058239A and CN101844770A disclose a technology for extracting alumina and white carbon black from fly ash. Although the method successfully utilizes Al2O3 and SiO2 in fly ash, the process requires repeated acid leaching, alkali leaching, calcination and other process steps, which are complicated and lengthy, and the product is difficult to causticize and sinter, and a large amount of CO2 is generated. The energy consumption and cost are too high, and it is difficult to industrialize production. Public patent CN101125656B discloses a method for extracting silicon and aluminum from fly ash. Although the method does not generate waste, it uses 40% causticizing alkali solution, and the cost of washing and filtering is still very high. In addition, a large amount of silicon-containing slag generated after aluminum extraction is used for cement after neutralization and drying. The product value is very low and it is not economically feasible. Public patent CN103121700A provides an alkali desiliconization and alkali lime sintering method. The method focuses on product purity, but ignores the high energy consumption required for alkali leaching and high-temperature roasting. Patents CN103145161B and CN114014329A use coal gangue to prepare pseudo-boehmite and co-produce white carbon black. The method uses carbonization and acidification to separate silicon and aluminum, and the alkaline leaching residue is sintered with sodium carbonate and limestone to recover CO2. However, the gas recovery of this method has extremely high requirements on the equipment. Repeated use of acid and alkali leaching not only results in excessive residue, but also extremely high energy consumption for drying. In summary, most of the existing technologies are aimed at aluminum-containing solid waste, and after acid dissolution, alkali dissolution, or multiple times, and then surface treatment, a modified siliceous filler is obtained. The process is lengthy, and how to directly utilize the residual acid in the wet slag is not considered, and the high cost caused by filtration and drying cannot be avoided. Taking the technology of producing polyaluminum sulfate by "one-step acid dissolution method" of low-grade ball clay as an example, the ball clay aluminate slag is a typical high-silicon slag, the main chemical component of which is SiO2, and it also contains a small amount of Al2O3, Fe2O3 and other residues. Due to the high acid content and extremely high water content in the wet slag, the colloidal wet slag is difficult to filter. If a large amount of water is used to wash the waste slag to neutrality and then filter it, it will also lead to high energy consumption, high cost equipment investment and secondary pollution. Therefore, new technologies to achieve harmless treatment of aluminate slag and obtain high-value siliceous materials still need to be developed.

[0005] White carbon black is a general term for amorphous silica products, mainly referring to precipitated silica, fumed silica and ultrafine silica gel, and also including powdered aluminum silicate and calcium silicate as additives. Its composition can be expressed as SiO2·nH2O, where nH2O exists in the form of surface hydroxyl groups. White carbon black is light, non-toxic and tasteless, and has the advantages of large specific surface area, high dispersibility, good chemical stability, high temperature resistance and good electrical insulation. It is used in many fields such as rubber industry, animal feed, catalysis, food, medicine, oral, nursing, papermaking, coatings, inks, and agrochemicals. As a rubber reinforcing agent, the amount of white carbon black used is very large, accounting for more than 35% of the total amount. In order to achieve a good reinforcing effect of white carbon black, there should be as many points of action as possible on the surface of its particles and rubber, especially the design of special-shaped structures or surface functionalized white carbon black powders, which can achieve the reinforcement and toughening effect of rubber composites. Regarding the composite technology of white carbon black, the patent CN103881420A uses starch and white carbon black to compound to prepare highly dispersible rubber fillers. Although this method solves the problem of dispersibility, it uses starch, which is costly and not conducive to industrialization. The patent CN105504345A uses precipitation method white carbon black and graphite flakes for wet grinding in an ethanol environment. Although it achieves functionalization, it does not consider the cost and environmental effects of ethanol at all. The patent CN113149070A uses titanium tetrachloride and sodium silicate to co-precipitate nuclei to obtain a white carbon black composite material with photocatalytic properties. The silicon tetrachloride used in this method is extremely expensive, and the treatment of the generated sodium chloride brine waste liquid is also a bottleneck of this technology. The patent CN101293656B uses microsilica powder and water glass to mix and adjust the pH to obtain a composite white carbon black material with a core-shell structure. This method also requires a large amount of water and surfactants, and wastewater is difficult to deal with.

[0006] White carbon black itself has some disadvantages, such as strong hydrophilicity, poor dispersibility, high surface energy, poor compatibility with rubber, etc. In order to overcome these disadvantages, its surface needs to be coated. The process includes: (1) organic silane coupling agent coating: silane coupling agent is a substance that can react chemically with inorganic materials and organic materials. By chemically bonding with the surface of white carbon black, it can effectively improve the dispersibility, lipophilicity and compatibility of white carbon black with organic materials; (2) polymer coating: using polymer to coat white carbon black can change its surface properties, such as improving its hydrophobicity, anti-fouling, anti-friction, etc.; (3) metal oxide coating: coating metal oxide can improve the high temperature resistance, oxidation resistance, catalytic activity, etc. of white carbon black; (4) nano material coating: by coating nano materials, white carbon black can be given new functions, such as conductivity, magnetism, optical properties, etc. Therefore, the development of coated precipitated silica to form a composite powder is of great significance for the technical improvement of new chemical products.

[0007] Existing research has been conducted on the composite coating of inorganic microparticles such as SiO2 with organic polymer emulsions to form a dispersed system of inorganic-organic composite particles. The composite particle system can be coated by electrostatic attraction, but the performance varies and it is difficult to form a universal technology. There is also a method to synthesize an ethanol solution of silica particles, modify the surface, and then use dispersion polymerization to achieve the coating of SiO2 with polystyrene, but the cost of the ethanol solution is extremely high and industrialization is not desirable. The existing technologies all adopt organic coating modification and no feasible technical solutions are given. At present, there are relatively few studies on the inorganic modification of white carbon black. Summary of the invention

[0008] In order to solve the above technical problems, the present invention provides a method for preparing a composite white carbon black material by solid phase wet grinding of aluminate slag extracted by sulfuric acid method and calcium, comprising the following steps:

[0009] The wet sample of the aluminate slag extracted by the sulfuric acid method is mixed with a calcium mineral or chemical raw material containing CaO in a ratio of residual acid H2SO4:CaO=1:(1-3) to perform a solid phase wet grinding reaction, and the obtained mixed slurry is dried or naturally air-dried to obtain a composite white carbon black powder;

[0010] The water content of the wet sample of the aluminate slag extracted by the sulfuric acid method is in the range of 40% to 60%, and the pH value is 0.5 to 2. The mass ratio of silicon slag solid, water and sulfuric acid in the wet sample of the aluminate slag extracted by the sulfuric acid method is 3:2:1. The mass content of SiO2 in the silicon slag solid is in the range of 93% to 95%, the mass content of Al2O3 is in the range of 4% to 5%, the mass content of Fe2O3 is in the range of 0.5% to 0.8%, and the total content of other impurities such as CaO, MnO, TiO2, K2O, Na2O, P2O5, etc. is less than 1.0%.

[0011] The solid phase wet grinding reaction is carried out in a ball mill, and the process parameters are preferably: the ball mill slurry filling rate is 28.0±1.0%, the ball mass ratio is 8.0±0.5%, the mass ratio of small ball to large ball of the ball mill medium is 2:1, and the grinding time is 4.0±0.5h.

[0012] The aluminate slag extracted by the sulfuric acid method is: a silicate slag obtained by acid leaching a mineral or solid waste containing aluminum and silicon as the main component, such as bauxite, kaolin, ball clay, coal gangue or fly ash, with sulfuric acid.

[0013] The calcium mineral or chemical raw material is one or more of calcite, dolomite, stalactite, shell, calcium oxide, light calcium carbonate, heavy calcium carbonate or dolomite.

[0014] The ball milling equipment is one of: zirconium oxide grinding jar and grinding balls, agate grinding jar and grinding balls, polytetrafluoroethylene grinding jar and grinding balls, nylon grinding jar and grinding balls, acid-resistant ceramic grinding jar and grinding balls, and polyurethane grinding jar and grinding balls.

[0015] The composite white carbon black material prepared by the method of the present invention can be used for manufacturing rubber.

[0016] The present invention further provides a method for preparing a composite white carbon black-doped rubber, comprising the following steps:

[0017] Take 50 parts of the composite white carbon black powder prepared by the above method, 100 parts of styrene-butadiene rubber, 1 part of stearic acid, 5 parts of zinc oxide, 3 parts of polyethylene glycol (4000), and accelerator DM e 1.2 parts, accelerator M d 0.7 parts, accelerator DPG e 0.5 parts of sulphur and 2 parts of sulfur are put into an open mill and plasticized at 40°C, left for more than 16 hours, then vulcanized and cooled for more than 10 hours to obtain a composite white carbon black material toughened styrene-butadiene rubber product.

[0018] The working principle of the method for preparing composite white carbon black material by solid phase wet grinding of aluminate slag with sulfuric acid and calcium provided by the present invention is as follows:

[0019] The invention wet-grinds the aluminate slag containing residual acid and the calcium-containing substance in a ball mill, generates hemihydrate calcium sulfate by reacting the calcium-containing substance with sulfuric acid in the acid slag, and the hemihydrate calcium sulfate coats the surface of precipitated silicon dioxide particles and further grows into whiskers to form a fibrous composite material. The specific surface area and whiteness are higher than those of the original acid slag dry powder.

[0020] The reaction between calcium-containing substances and sulfuric acid is an exothermic reaction, which can fully utilize the heat energy generated by itself to accelerate the reaction and powder drying.

[0021] Solid-phase wet grinding reaction overcomes the high energy consumption problem required for filtration, washing, drying, etc. through particle collision.

[0022] If calcium material containing carbonate is used as the raw material for the solid phase wet grinding reaction, carbon dioxide will be released during the reaction, and some water vapor will be generated during the wet grinding process. This reaction can keep the material loose, effectively avoid aggregation between particles, and help reduce the particle size of the powder to obtain a powder with a large specific surface area.

[0023] The present invention provides a method for manufacturing a composite silica-doped rubber. The fibrous composite silica material can achieve a mechanical enhancement effect, has adjustable surface properties, and has better compatibility with base materials such as polymer rubber and plastic. The composite silica-doped styrene-butadiene rubber obtained by the present invention has tensile properties and other mechanical properties that meet the HG / T 2404 standard.

[0024] Beneficial effects of the present invention:

[0025] The present invention solves the filtering problem of aluminate slag extracted by colloidal sulfuric acid method by wet grinding method, and utilizes residual acid and water in wet slag to generate hemihydrate calcium sulfate whiskers, which are coated on the surface of precipitated silica particles to prepare CaSO4·0.5H2O@SiO2·nH2O or gypsum@white carbon black composite powder. The aluminate slag extracted in the present invention can be directly utilized without washing and deacidification, and without drying. The wet grinding process is simple, the energy consumption is low, and the product performance is excellent. The hemihydrate calcium sulfate CaSO4·0.5H2O obtained by the present invention is also called gypsum whiskers, which has excellent mechanical properties. The product is a white loose needle-like object with a complete and smooth appearance and a good aspect ratio. The hemihydrate calcium sulfate whisker coated precipitated silica composite powder obtained by the method has the advantages of high temperature resistance, good toughness, acid and alkali corrosion resistance, high strength, high modulus, etc., and CaSO4·0.5H2O has good lipophilicity, so it has good compatibility with polymer materials. Gypsum@white carbon black has excellent strengthening and toughening functions and is non-toxic. Adding it to polymer materials such as rubber and plastic can greatly improve the mechanical properties of rubber. In addition, calcium sulfate whiskers wrapped on the surface of SiO2 particles can shield the non-ferrous metals that have not been completely removed, achieving a whitening effect.

[0026] The present invention not only effectively utilizes the siliceous waste residue in the aluminate slag extracted by the sulfuric acid method, but also utilizes the residual acid and water in the acid slag to form coated calcium sulfate whiskers, thereby solving the thorny acid hazardous waste problem. The method simplifies the process, and only requires wet grinding, and after drying, a small amount of water in the wet-grinded product is removed to obtain a powder. The present invention avoids high-energy consumption steps such as washing, filtering, and drying of the aluminate slag, simplifies the process, makes full use of materials, realizes low-energy conversion, and realizes the green conversion of solid hazardous waste. After optimizing the solid-phase wet-grinding reaction process parameters such as the ball mill slurry filling rate, the ball mass ratio, and the grinding time, a fibrous composite silica powder with excellent performance is obtained, the whisker length is 16.47-35.79, the average length is 27.96μm, the aspect ratio reaches 13.6, its specific surface area and particle size reach the ultrafine silica standard, and the dispersibility is better; the solid-phase wet-grinding reaction process parameters are too high or too low, and the above-mentioned fibrous composite silica morphology effect cannot be formed. The obtained fibrous composite white carbon black is applied to rubber filler, which has remarkable reinforcing effect and good economic and environmental benefits. No "three wastes" are generated, which truly realizes "turning waste into treasure". BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 This is the X-ray diffraction pattern of aluminum slag extracted from ball clay in Example 1 of the present invention.

[0028] Figure 2 This is a SEM image of aluminum waste slag extracted from ball clay after acid leaching in Example 1 of the present invention; it can be seen from the image that after acid leaching, the lamellar structure of the ball clay is destroyed, a large number of holes and gaps appear, the surface becomes rough and irregular, and the average particle size is 50um.

[0029] Figure 3 This is the particle size distribution diagram of aluminum waste slag obtained in Example 1 of the present invention.

[0030] Figure 4 This is a SEM image of the composite silica material of Example 1 of the present invention. DETAILED DESCRIPTION

[0031] The present invention is further described by way of the following examples, which do not limit the present invention in any way. Without departing from the technical solution of the present invention, any modification or change made to the present invention that is easily implemented by a person of ordinary skill in the art will fall within the scope of the claims of the present invention.

[0032] Embodiment 1:

[0033] a: Activated ball clay (containing SiO2 53.08%, Al2O3 33.31% and other small amounts of metal oxides) was acid-leached with 35% sulfuric acid at a mass ratio of 1:2.18, the reaction temperature was 90°C, and the reaction time was 4 hours;

[0034] b: The suspension obtained in step a is filtered under 20 MPa pressure to obtain sulfuric acid-extracted aluminate slag. Figure 1-3 As shown, it was determined that the water content in the acid residue was 45%, and the concentration of the residual acid sulfuric acid was 2.5 mol / L;

[0035] c: Add light calcium carbonate solid to the acid residue obtained in step b at a molar ratio of H2SO4:CaO of 1:2. The mixture is solid-phase wet-milled in a high-speed ball mill for 4 hours to obtain a composite filler, wherein the ball mill is a zirconia ball mill, the ball milling medium is zirconia balls of φ=5mm and φ=10mm, the ball mass ratio is 1:12, and the slurry filling rate is 28%;

[0036] e: Dry the composite filler at 105°C, grind it after drying, and obtain composite white carbon black material. Figure 4 As shown, the product has a large number of thin whiskers, and the hemihydrate calcium sulfate whiskers are coated on the silicon dioxide crystals.

[0037] f: Take 50 parts of the composite white carbon black material obtained in step e, 100 parts of styrene-butadiene rubber, 1 part of stearic acid, 5 parts of zinc oxide, 3 parts of polyethylene glycol (4000), and accelerator DM e 1.2 parts, accelerator M d 0.7 parts, accelerator DPG e 0.5 parts of sulphur and 2 parts of sulfur were put into an open mill and plasticized at 40°C, left for 16 hours, vulcanized and cooled for 10 hours to obtain a composite white carbon black material toughened styrene-butadiene rubber product.

[0038] The test results of composite silica material and toughened styrene-butadiene rubber products are as follows:

[0039]

[0040]

[0041] Embodiment 2:

[0042] a: acid leaching of bauxite and 35% sulfuric acid at a molar ratio of 1:3, reaction temperature 70°C, reaction time 3 hours;

[0043] b: The suspension obtained in step a was filtered to obtain sulfuric acid-extracted aluminum acid slag. The water content in the acid slag was 56%, and the concentration of the residual acid H2SO4 was 1.05 mol / L;

[0044] c: Add calcite to the acid residue obtained in step b at a molar ratio of H2SO4:CaO of 1:1.2. The mixture is solid-phase wet-milled in a high-speed ball mill for 5 hours to obtain a composite powder, wherein the ball mill is a polyurethane ball mill, the ball milling medium is alumina balls of φ=5mm and φ=10mm, the ball mass ratio is 1:12, and the slurry filling rate is 28%;

[0045] e: Dry the composite filler at 105° C., grind it after drying, and obtain a composite silica material.

[0046] f: Take 50 parts of the composite white carbon black material obtained in step e, 100 parts of styrene-butadiene rubber, 1 part of stearic acid, 5 parts of zinc oxide, 3 parts of polyethylene glycol (4000), and accelerator DM e 1.2 parts, accelerator M d 0.7 parts, accelerator DPG e 0.5 parts of sulphur and 2 parts of sulfur were put into an open mill and plasticized at 40°C, left for 16 hours, vulcanized and cooled for 10 hours to obtain a composite white carbon black material toughened styrene-butadiene rubber product.

[0047] The test results of composite silica material and toughened styrene-butadiene rubber products are as follows:

[0048]

[0049] Embodiment 3:

[0050] a: calcined activated kaolin and 35% sulfuric acid were acid-leached at a mass ratio of 1:2.18, the reaction temperature was 85°C, and the reaction time was 4 hours;

[0051] b: The suspension obtained in step a was filtered to obtain sulfuric acid-extracted aluminum acid slag. The water content in the acid slag was 45%, and the concentration of residual sulfuric acid was 2.5 mol / L;

[0052] c: Add calcite to the acid residue obtained in step b at a molar ratio of H2SO4:CaO of 1:1.5. The mixture is solid-phase wet-milled in a high-speed ball mill for 4 hours to obtain a composite powder, wherein the ball mill is an agate ball mill, the ball milling medium is agate balls of φ=5mm and φ=10mm, the ball mass ratio is 1:12, and the slurry filling rate is 28%;

[0053] e: Dry the composite filler at 105° C., grind it after drying, and obtain a composite silica material.

[0054] f: Take 50 parts of the composite white carbon black material obtained in step e, 100 parts of styrene-butadiene rubber, 1 part of stearic acid, 5 parts of zinc oxide, 3 parts of polyethylene glycol (4000), and accelerator DM e 1.2 parts, accelerator M d 0.7 parts, accelerator DPG e 0.5 parts of sulphur and 2 parts of sulfur were put into an open mill and plasticized at 40°C, left for 16 hours, vulcanized and cooled for 10 hours to obtain a composite white carbon black material toughened styrene-butadiene rubber product.

[0055] The test results of composite silica materials and toughened styrene-butadiene rubber products are shown in the following table

[0056]

[0057] Embodiment 4:

[0058] a: Calcinated coal gangue and 35% sulfuric acid were acid-leached at a mass ratio of 1:3.0, the reaction temperature was 80°C, and the reaction time was 4 hours;

[0059] b: The suspension obtained in step a was filtered to obtain sulfuric acid-extracted aluminum acid residue. The water content in the acid residue was 55%, and the concentration of residual sulfuric acid was 1.5 mol / L;

[0060] c: Add heavy calcium carbonate to the acid residue obtained in step b at a molar ratio of H2SO4:CaO of 1:1.5. The mixture is solid-phase wet-milled in a high-speed ball mill for 4 hours to obtain a composite powder, wherein the ball mill is an acid-resistant ceramic ball mill, the ball milling medium is φ=5mm and φ=10mm acid-resistant ceramic balls, the ball mass ratio is 1:12, and the slurry filling rate is 28%;

[0061] e: Dry the composite filler at 105° C., grind it after drying, and obtain a composite silica material.

[0062] f: Take 50 parts of the composite white carbon black material obtained in step e, 100 parts of styrene-butadiene rubber, 1 part of stearic acid, 5 parts of zinc oxide, 3 parts of polyethylene glycol (4000), and accelerator DM e 1.2 parts, accelerator M d0.7 parts, accelerator DPG e 0.5 parts of sulphur and 2 parts of sulfur were put into an open mill and plasticized at 40°C, left for 16 hours, vulcanized and cooled for 10 hours to obtain a composite white carbon black material toughened styrene-butadiene rubber product.

[0063] The test results of composite silica materials and toughened styrene-butadiene rubber products are shown in the following table

[0064]

[0065] Embodiment 5:

[0066] a: 20 parts of activated ball clay (SiO2 53%, Al2O3 33% and other small amounts of metal oxides) were acid-leached with 35% sulfuric acid at a mass ratio of 1:2.2, at a reaction temperature of 90°C and a reaction time of 3.5 hours;

[0067] b: The suspension obtained in step a was filtered to obtain sulfuric acid-extracted aluminum acid slag. The water content in the acid slag was 45%, and the concentration of residual sulfuric acid was 2.5 mol / L;

[0068] c: Add dolomite solid to the acid residue obtained in step b at a molar ratio of H2SO4:CaO of 1:2. The mixture is solid-phase wet-milled in a high-speed ball mill for 4 hours to obtain a composite powder, wherein the ball mill is a polytetrafluoroethylene mill, the ball milling medium is zirconium silicate balls of φ=5mm and φ=10mm, the ball mass ratio is 1:12, and the slurry filling rate is 28%;

[0069] e: Dry the composite filler at 105° C., grind it after drying, and obtain a composite silica material.

[0070] f: Take 50 parts of the composite white carbon black material obtained in step e, 100 parts of styrene-butadiene rubber, 1 part of stearic acid, 5 parts of zinc oxide, 3 parts of polyethylene glycol (4000), and accelerator DM e 1.2 parts, accelerator M d 0.7 parts, accelerator DPG e 0.5 parts of sulphur and 2 parts of sulfur were put into an open mill and plasticized at 40°C, left for 16 hours, vulcanized and cooled for 10 hours to obtain a composite white carbon black material toughened styrene-butadiene rubber product.

[0071] The test results of composite silica materials and toughened styrene-butadiene rubber products are shown in the following table

[0072]

[0073] Embodiment 6:

[0074] a: Fly ash and concentrated sulfuric acid were acid-leached in a molar ratio of 1:3, the reaction temperature was 85°C, and the reaction time was 5.5 hours;

[0075] b: dilute the suspension obtained in step a with water, and then filter press to obtain sulfuric acid-extracted aluminum acid slag. The water content in the acid slag is 45%, and the concentration of residual sulfuric acid is 6.5 mol / L;

[0076] c: Add shell powder solid to the acid residue obtained in step b at a molar ratio of H2SO4:CaO of 1:2. The mixture is solid-phase wet-milled in a high-speed ball mill for 4 hours to obtain a composite powder, wherein the ball mill is a nylon ball mill, the ball milling medium is φ=5mm and φ=10mm zirconium oxide balls, the ball mass ratio is 1:12, and the slurry filling rate is 28%;

[0077] e: Dry the composite filler at 105° C., grind it after drying, and obtain a composite silica material.

[0078] f: Take 50 parts of the composite white carbon black material obtained in step e, 100 parts of styrene-butadiene rubber, 1 part of stearic acid, 5 parts of zinc oxide, 3 parts of polyethylene glycol (4000), and accelerator DM e 1.2 parts, accelerator M d 0.7 parts, accelerator DPG e 0.5 parts of sulphur and 2 parts of sulfur were put into an open mill and plasticized at 40°C, left for 16 hours, vulcanized and cooled for 10 hours to obtain a composite white carbon black material toughened styrene-butadiene rubber product.

[0079] The test results of composite silica materials and toughened styrene-butadiene rubber products are shown in the following table

[0080]

Claims

1. A method for preparing composite white carbon black by solid phase wet grinding of aluminate slag extracted by sulfuric acid method and calcium, characterized in that: The following steps are involved: The wet sample of aluminate slag extracted by sulfuric acid method is mixed with calcium minerals or chemical raw materials containing CaO in a ratio of residual acid H2SO4:CaO=1:(1-3) to carry out solid phase wet grinding reaction. The obtained mixed slurry is dried or naturally air-dried to obtain composite white carbon black powder.

2. The method for preparing composite white carbon black by solid phase wet grinding of aluminate slag extracted by sulfuric acid process and calcium according to claim 1, characterized in that: The water content of the wet sample of the aluminate slag extracted by the sulfuric acid method is in the range of 40% to 60%, and the pH value is 0.5 to 2; the mass ratio of silicon slag solid, water and sulfuric acid in the wet sample of the aluminate slag extracted by the sulfuric acid method is 3:2:

1.

3. The method for preparing composite white carbon black by solid phase wet grinding of aluminate slag with sulfuric acid process and calcium addition according to claim 2, characterized in that: The mass content of SiO2 in the silicon slag solid is in the range of 93% to 95%, the mass content of Al2O3 is in the range of 4% to 5%, the mass content of Fe2O3 is in the range of 0.5% to 0.8%, and the total content of other impurities is less than 1.0%.

4. The method for preparing composite white carbon black by solid phase wet grinding of aluminate slag extracted by sulfuric acid process and calcium addition according to claim 1, characterized in that: The solid phase wet grinding reaction is carried out in a ball mill, the ball mill slurry filling rate is 28.0±1.0%, the ball mass ratio is 8.0±0.5%, the mass ratio of small ball to large ball of the ball mill medium is 2:1, and the grinding time is 4.0±0.5h.

5. The method for preparing composite white carbon black by solid phase wet grinding of aluminate slag extracted by sulfuric acid process and calcium according to claim 1, characterized in that: The aluminate slag extracted by the sulfuric acid method is: a silicate slag obtained by acid leaching a mineral or solid waste containing aluminum and silicon as the main component, such as bauxite, kaolin, ball clay, coal gangue or fly ash, with sulfuric acid.

6. The method for preparing composite white carbon black by solid phase wet grinding of aluminate slag extracted by sulfuric acid process and calcium addition according to claim 1, characterized in that: The calcium mineral or chemical raw material is one or more of calcite, dolomite, stalactite, shell, calcium oxide, light calcium carbonate, heavy calcium carbonate or dolomite.

7. The method for preparing composite white carbon black by solid phase wet grinding of aluminate slag extracted by sulfuric acid process and calcium according to claim 1, characterized in that: The ball milling equipment is one of: zirconium oxide grinding jar and grinding balls, agate grinding jar and grinding balls, polytetrafluoroethylene grinding jar and grinding balls, nylon grinding jar and grinding balls, acid-resistant ceramic grinding jar and grinding balls, and polyurethane grinding jar and grinding balls.

8. A composite white carbon black material, characterized in that: The composite silica is prepared by the method for preparing composite silica by solid phase wet grinding of aluminate slag extracted by sulfuric acid method and adding calcium according to any one of claims 1 to 7.

9. A method for producing a composite white carbon black-doped rubber, characterized in that it comprises the following steps: Take 50 parts of the composite white carbon black material according to claim 8, 100 parts of styrene-butadiene rubber, 1 part of stearic acid, 5 parts of zinc oxide, 3 parts of polyethylene glycol (4000), and accelerator DM e 1.2 parts, accelerator M d 0.7 parts, accelerator DPG e 0.5 parts of sulphur and 2 parts of sulfur are put into an open mill and plasticized at 40°C, left for more than 16 hours, then vulcanized and cooled for more than 10 hours to obtain a composite white carbon black material toughened styrene-butadiene rubber product.

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