阅读说明：本技术 复合功能型陶粒的制备方法 (Preparation method of composite functional ceramsite ) 是由 苏英 黄震宇 陈振东 贺行洋 陈顺 陈威 杨进 王迎斌 熊国庆 刘巧 江友志 于 2019-11-13 设计创作，主要内容包括：本发明公开了一种复合功能型陶粒的制备方法,采用以下方法制备：将氧化钛粉,加入到氢氧化钠水溶液中制备前驱体混合液；然后加入经表面活化的中空纳米二氧化硅微球高温处理,然后冷却至室温后,离心、洗涤分离,制备表面高负载氧化钛纳米管的多孔空心二氧化硅微球；将长链有机硅烷和表面高负载氧化钛纳米管的多孔空心二氧化硅微球加入到去离子水中反应,离心、分离获得改性氧化钛纳米管的多孔空心二氧化硅微球；将湿磨工业固废料浆、引气剂、增稠剂和改性氧化钛纳米管的多孔空心二氧化硅微球混合、造粒,室温养护得到复合功能型的陶粒。本发明生产成本低、工艺简单,制备的陶粒比表面积大,硬度高,强度大,吸附力好、再生能力强。(The invention discloses a preparation method of composite functional ceramsite, which comprises the following steps: adding titanium oxide powder into a sodium hydroxide aqueous solution to prepare a precursor mixed solution; then adding the hollow nano-silica microspheres subjected to surface activation for high-temperature treatment, cooling to room temperature, centrifuging, washing and separating to prepare porous hollow silica microspheres with titanium oxide nanotubes loaded on the surface; adding long-chain organosilane and the porous hollow silica microspheres with the surfaces highly loaded with the titanium oxide nanotubes into deionized water for reaction, centrifuging and separating to obtain the porous hollow silica microspheres of the modified titanium oxide nanotubes; and mixing the wet-milled industrial solid waste slurry, the air entraining agent, the thickening agent and the porous hollow silica microspheres of the modified titanium oxide nanotubes, granulating, and maintaining at room temperature to obtain the composite functional ceramsite. The invention has the advantages of low production cost and simple process, and the prepared ceramsite has the advantages of large specific surface area, high hardness, high strength, good adsorption force and strong regeneration capacity.)

1. The preparation method of the composite functional ceramsite is characterized by comprising the following steps of:

step T1: adding 10-15 parts by weight of ball-milled titanium oxide powder into a sodium hydroxide aqueous solution, and adding 1-2 parts by weight of sodium sulfate or ammonium sulfate to prepare a precursor mixed solution; then adding 5-10 parts by weight of surface activated hollow nano-silica microspheres, transferring to a high-pressure reaction kettle for high-temperature treatment, cooling to room temperature, centrifuging, washing, separating and drying to prepare porous hollow silica microspheres with titanium oxide nanotubes loaded on the surface;

step T2: adding 3-5 parts by weight of long-chain organosilane and 5-10 parts by weight of porous hollow silica microspheres with highly-loaded titanium oxide nanotubes on the surface into deionized water, reacting under mechanical stirring, centrifuging, and separating to obtain porous hollow silica microspheres of modified titanium oxide nanotubes;

step T3: 100 parts by weight of wet-milled industrial solid waste slurry with the solid content of 60-80 wt%, 1-2 parts by weight of air entraining agent, 1-2 parts by weight of thickening agent and 10-20 parts by weight of porous hollow silica microspheres of modified titanium oxide nanotubes are mixed, granulated and maintained at room temperature to obtain the composite functional ceramsite.

2. The method for preparing composite functional ceramsite according to claim 1, wherein in step T1, the particle size range of the ball-milled titanium oxide powder is 0.2-0.4 μm; the high-temperature treatment temperature is 150-200 ℃, the treatment time is 12-24 hours, and the pressure is 2-4 MPa.

3. The method for preparing composite functional ceramsite according to claim 1, wherein in step T1, said aqueous solution of sodium hydroxide is 5% aqueous solution of sodium hydroxide, and the amount added is 20 parts by weight.

4. The method for preparing the composite functional ceramsite according to claim 1, wherein in the step T2, the mechanical stirring time is 3-5 hours; the long-chain organosilane is polyether silane or organosilicon long-chain quaternary ammonium salt.

5. The method for preparing the composite functional ceramsite according to claim 1, wherein in the step T3, the wet-milled industrial solid waste slurry is obtained by wet-milling at least one of fly ash, slag and carbide slag to have a particle size of 6-8 μm.

6. The method for preparing the composite functional ceramsite according to claim 1, wherein in the step T3, the air-entraining agent is rosin resin; the thickener is gelatin.

7. The method for preparing the composite functional ceramsite according to any one of claims 1 to 6, wherein the surface-activated hollow nano-silica microspheres are prepared by the following method:

step S1: in 100 parts by weight of reverse microemulsion, taking 10-15 parts by weight of epoxy silane and 5-10 parts by weight of aminosilane as reaction raw materials, adding 1-2 parts by weight of pore-forming agent, 1-2 parts by weight of surfactant and 1-2 parts by weight of ammonia water, reacting at room temperature for 4-8 hours, centrifuging, washing and drying, and collecting a product to obtain a hollow nano silicon dioxide microsphere rich in surface groups;

step S2: dispersing 5-10 parts by weight of hollow nano-silica microspheres into 100 parts by weight of deionized water, adding 1-2 parts by weight of biological polysaccharide, mechanically stirring for 2-4 hours, centrifuging, and washing to obtain the surface-activated hollow nano-silica microspheres.

8. The method for preparing the composite functional ceramsite according to claim 7, wherein in the step S1, the inverse microemulsion is 100 parts by weight of a mixed solution of water and cyclohexane, and the mass ratio of the two is 10-6: 1.

9. The method for preparing functional composite ceramsite according to claim 7, wherein in step S1, the pore-forming agent is styrene-polyacrylic acid-polymethylsilane or styrene-polymethyl acrylate-polymethylsilane; the surfactant is lecithin or polyether sulfonate.

10. The method for preparing functional composite ceramsite according to claim 7, wherein in step S2, the biological polysaccharide is chitosan or sodium alginate.

Technical Field

The invention relates to the field of environment-friendly materials, in particular to a preparation method of composite functional ceramsite.

Background

In recent years, with the continuous development of world economy, the modern industry is highly concentrated. Industrial wastewater contains a large amount of heavy metals, which, although low in content, have become one of the major environmental problems threatening the development of human beings. As a method for effectively removing heavy metals, the adsorption technology plays an irreplaceable important role in the fields of water pollution control and water purification.

Due to the special structure and properties of the nano-material, the nano-material has been paid much attention by researchers, and is widely applied to various industrial fields, and environmental researchers also begin to explore the application of the nano-material in the environment. Currently, different nano-materials have been gradually used in the field of adsorption materials to obtain excellent effects, for example, nano-particle titanium dioxide is widely used as an adsorbent, a process catalyst or a photocatalyst due to its high specific surface area and semiconductor characteristics. Commercial production of nanoparticulate titania is typically achieved by hydrolysis of acidic titanyl compounds (e.g., titanyl chloride or sulfate) followed by heat treatment. For example titanyl sulfate is produced by sulfuric acid digestion of a titaniferous feed material. In order to make the effect better, the adsorption capacity of the nano material is enhanced by adopting the porous hollow silica microspheres and titanium oxide nano particles.

As for the porous silicon dioxide hollow structure material, the porous silicon dioxide hollow structure material has the characteristics of high purity, low density, high specific surface area, relatively stable chemical property, good compatibility with other materials and the like, and is applied to the aspects of catalyst carriers, pollutant adsorbents, environment purification functional materials, high performance liquid chromatography fillers, gas separation materials, heat insulation materials, drug controlled release and the like.

CN 109219577 a discloses a process for obtaining nanoparticulate titania in agglomerated form from a hydrolyzed acidic titanyl compound by hydrolyzing the titanyl compound in an aqueous solution of an acidic titanyl compound to produce a titania-hydrate suspension, filtering the suspension and washing the resulting titania-hydrate filter cake; neutralizing the filter cake, and carrying out heat treatment on the filter cake to obtain the nano-particle titanium dioxide. Since a large amount of water is required for washing in the hydrolysis process and the neutralization process, a large amount of waste water is generated. In addition, heat treatment of the filter cake to produce nanoparticulate titanium dioxide can affect the activity of the titanium dioxide.

CN 101966994A discloses a preparation method of porous silica hollow microspheres, which comprises the steps of preparing polyacrylamide, porous polyacrylamide gel and polyacrylamide/silica composite microspheres to obtain the porous silica hollow microspheres. The method has the defects of complex reaction steps, high control difficulty, high-temperature treatment after drying, reduced surface activity of the obtained porous silicon dioxide hollow microspheres and no contribution to further synthesis and use of materials.

The full combination of the titanium dioxide and the silicon dioxide hollow microspheres for the adsorption and removal of heavy metal ions has great significance, but the preparation of the titanium dioxide/silicon dioxide hollow microspheres which are practical at present and have good effects still has certain difficulty.

Disclosure of Invention

The invention aims to solve the technical problems and provides a preparation method of composite functional ceramsite, which has the advantages of low production cost, simple process, large specific surface area, high hardness, high strength, good adsorption force, strong regeneration capacity, long service life and wide adsorption objects.

The technical scheme comprises the following steps:

step T1: adding 10-15 parts by weight of ball-milled titanium oxide powder into a sodium hydroxide aqueous solution, and adding 1-2 parts by weight of sodium sulfate or ammonium sulfate to prepare a precursor mixed solution; then adding 5-10 parts by weight of surface activated hollow nano-silica microspheres, transferring to a high-pressure reaction kettle for high-temperature treatment, cooling to room temperature, centrifuging, washing, separating and drying to prepare porous hollow silica microspheres with titanium oxide nanotubes loaded on the surface;

step T2: adding 3-5 parts by weight of long-chain organosilane and 5-10 parts by weight of porous hollow silica microspheres with highly-loaded titanium oxide nanotubes on the surface into deionized water, reacting under mechanical stirring, centrifuging, and separating to obtain porous hollow silica microspheres of modified titanium oxide nanotubes;

step T3: 100 parts by weight of wet-grinding industrial solid waste slurry containing 60-80 wt% of solid, 1-2 parts by weight of air entraining agent, 1-2 parts by weight of thickening agent and 10-20 parts by weight of porous hollow silica microspheres of modified titanium oxide nanotubes are mixed, granulated and maintained at room temperature to obtain the composite functional ceramsite.

In the step T1, the particle size range of the ball-milled titanium oxide powder is 0.2-0.4 μm; the high-temperature treatment temperature is 150-200 ℃, the treatment time is 12-24 hours, and the pressure is 2-4 MPa.

In the step T1, the aqueous sodium hydroxide solution was a 5% aqueous sodium hydroxide solution, and the amount added was 20 parts by weight.

In the step T2, the mechanical stirring time is 3-5 hours; the long-chain organosilane is polyether silane or organosilicon long-chain quaternary ammonium salt.

In the step T3, the wet-milling industrial solid waste is obtained by wet-milling one of fly ash, slag and carbide slag until the particle size is 6-8 μm.

In the step T3, the air entraining agent is rosin resin; the thickener is gelatin.

The surface-activated hollow nano-silica microspheres are prepared by the following method:

step S1: in 100 parts by weight of reverse microemulsion, taking 10-15 parts by weight of epoxy silane and 5-10 parts by weight of aminosilane as reaction raw materials, adding 1-2 parts by weight of pore-forming agent, 1-2 parts by weight of surfactant and 1-2 parts by weight of ammonia water, reacting at room temperature for 4-8 hours, centrifugally washing and drying, and collecting a product to obtain a hollow nano silicon dioxide microsphere rich in surface groups;

step S2: dispersing 5-10 parts by weight of hollow nano-silica microspheres into 100 parts by weight of deionized water, adding 1-2 parts by weight of biological polysaccharide, mechanically stirring for 2-4 hours, centrifuging, and washing to obtain the surface-activated hollow nano-silica microspheres.

In the step S1, the reverse microemulsion is 100 parts by weight of a mixed solution of water and cyclohexane, and the mass ratio of the two is 10-6: 1.

In the step S1, the pore-forming agent is styrene-polyacrylic acid-polymethylsilane or styrene-polymethyl acrylate-polymethylsilane; the surfactant is lecithin or polyether sulfonate.

In step S2, the biological polysaccharide is chitosan or sodium alginate.

In view of the problems in the background art, the inventor makes the following improvements:

in order to solve the problems in the background art, the invention utilizes the inverse emulsion method to prepare the hollow nano-silica microspheres rich in the surface groups economically and efficiently, and the hollow nano-silica microspheres rich in the surface groups are obtained by simple centrifugal washing and drying in the preparation process. In addition, the pretreated titanium oxide powder can be converted into the titanium oxide nanotube by a heating and pressurizing method under the condition that a template agent sodium sulfate or ammonium sulfate exists, the process operation is simple, and the preparation of the titanium oxide nanotube is stable and controllable. The method is further combined with the wet-grinding industrial solid waste slurry, and the characteristic of fine particle size and the high-activity particle-containing component of the wet-grinding industrial solid waste slurry can be utilized to promote high-activity reaction while reducing the water consumption for granulation and improving the working performance, so that the strength and the stability of the prepared composite functional ceramsite are improved, the ceramsite can be applied to improve water and environment, and the reutilization of industrial solid waste can be realized.

Has the advantages that:

the method comprises the steps of firstly preparing hollow nano-silica microspheres rich in surface groups, then adding biological polysaccharide to realize large-scale group formation on the surfaces of the microspheres, and obtaining surface-activated hollow nano-silica microspheres, wherein the silica microspheres obtained by the method have the characteristics of rich active sites and good titanium oxide cohesiveness; the titanium oxide nano tube is efficiently loaded to the silicon dioxide microsphere by using the ball-milled titanium oxide powder through a hydrothermal method, and then modified by using long-chain organosilane, so that the titanium oxide nano tube/porous hollow silicon dioxide microsphere with high dispersion stability and stable activity is prepared; the porous hollow silica microspheres and the wet-grinding industrial solid waste slurry are mixed to prepare the composite functional ceramsite, and the ceramsite has the characteristics of large specific surface area, multiple micropores, high hardness and good adsorption performance, can effectively adsorb heavy metal ions and organic matters, can decompose the organic matters under the illumination, and has good regeneration capacity and long service life. The ceramsite prepared by the method can be used for sewage treatment, can also be used in the fields of health care, air purification, water purification and the like, and has wide adaptability.

Detailed Description