阅读说明：本技术 一种活性硅铝粉的制备方法 (Preparation method of active silicon-aluminum powder ) 是由 于向真 于 2019-11-27 设计创作，主要内容包括：本发明公开了一种活性硅铝粉的制备方法,将一定浓度的水玻璃与偏铝酸钠溶液按体积比0.1~10：0.1~10混合后,与酸在20℃~90℃温度下进行反应,得到羟基二氧化硅/氧化铝沉淀浆液；浆液在30℃~200℃温度下老化15分钟~12小时；将浆液过滤、洗涤,滤饼经干燥得到活性硅铝粉。本发明通过化学法生产活性硅铝粉,没有煅烧等工序,其生产工艺简单,能耗低,并且生产的硅铝粉杂质含量低、比表面积大、孔体积大。(The invention discloses a preparation method of active aluminum silicate powder, which comprises the following steps of mixing water glass with a certain concentration and a sodium metaaluminate solution according to a volume ratio of 0.1-10: 0.1-10, and reacting with acid at the temperature of 20-90 ℃ to obtain hydroxyl silicon dioxide/alumina precipitation slurry; aging the slurry for 15 minutes to 12 hours at the temperature of 30 to 200 ℃; filtering and washing the slurry, and drying a filter cake to obtain the active silica-alumina powder. The invention produces the active silicon-aluminum powder by a chemical method without the working procedures of calcination and the like, has simple production process and low energy consumption, and the produced silicon-aluminum powder has low impurity content, large specific surface area and large pore volume.)

1. The preparation method of the active silicon-aluminum powder is characterized by comprising the following steps:

1) the volume ratio of the water glass with a certain concentration to the sodium metaaluminate solution is 0.1-10: 0.1-10, and reacting with acid at the temperature of 20-90 ℃ to obtain hydroxyl silicon dioxide/alumina precipitation slurry;

2) aging the slurry at 30-200 ℃ for 15 minutes-12 hours;

3) filtering and washing the slurry, and drying a filter cake to obtain the active silica-alumina powder.

2. The method for preparing the active silicon-aluminum powder according to claim 1, wherein the concentration of the water glass in the step 1) is 20-300 g/l based on the dry basis of the silicon oxide.

3. The method for preparing active silicon-aluminum powder according to claim 1, wherein the concentration of the sodium metaaluminate in the step 1) is 15-150 g/l based on the dry basis of the alumina.

4. The method for preparing activated silicon-aluminum powder according to claim 1, wherein the acid in step 1) is any one or a mixture of sulfuric acid, hydrochloric acid, nitric acid, acetic acid and formic acid, and the pH of the slurry after the reaction with the acid is 6.0-10.5.

5. The method for preparing active silica-alumina powder as claimed in claim 1, wherein the low temperature N of the active silica-alumina powder obtained in step 3)₂The specific adsorption surface area is 120-1000 m²The pore volume is 0.1-2.0 ml/g.

Technical Field

The invention belongs to the field of novel materials, and relates to a preparation method of active silica-alumina powder, which can be used for producing and manufacturing catalysts, molecular sieves, fire resistance, heat preservation, adsorbents and the like.

Background

The silica-alumina powder in the present market is prepared by using silica-alumina ore as a raw material and processing the raw material through processes of impurity removal, filtration, superfine processing, calcination, classification, modification and the like, has the advantages of strong adhesion rate, high whiteness, uniform particle size distribution, particularly good intermiscibility with polymers, strong reinforcement and excellent wear resistance, is widely applied to industries such as casting coatings, rubber, plastics, magnetic materials, medicines and the like, and can replace high-cost fillers such as alumina powder, silica micropowder, lithopone, titanium dioxide and the like in a high proportion. But their impurity contents such as Fe, Mg, Ca, Na, K, etc. are high, and their specific surface area is generally 10-60m²The pore volume is below 0.12ml/g, so that the method cannot be used for preparing products with high purity requirements, such as catalysts, molecular sieves and the like.

Chinese patent CN108706614A discloses a method for preparing active silica-alumina powder, which is to mix quartz sand, aluminum hydroxide and soda ash uniformly according to a certain proportion, produce sodium aluminosilicate solution by melting at high temperature, react with high-temperature kiln acid tail gas to generate hydroxyl silica/alumina precipitate and sodium salt, and prepare the active silica-alumina powder through washing and drying, wherein the concentration of the acid tail gas is lower, generally about 40% (volume), which affects the reaction speed, and the active silica-alumina powder needs to be roasted at 1400 ℃, which has high energy consumption.

Disclosure of Invention

The invention provides a method for preparing high-quality active silica-alumina powder by a chemical method, aiming at overcoming the defects of high impurity content, small specific surface area, low pore volume, high energy consumption and the like of silica-alumina powder in the existing market.

The active silica-alumina powder comprises amorphous silica and alumina as main components, and has a specific surface area of 120-1000 m²The pore volume is 0.1-2.0 ml/g.

The technical scheme adopted by the invention is as follows: a preparation method of active silicon-aluminum powder comprises the following steps:

1) the volume ratio of the water glass with a certain concentration to the sodium metaaluminate solution is 0.1-10: 0.1-10, and reacting with acid at the temperature of 20-90 ℃ to obtain hydroxyl silicon dioxide/alumina precipitation slurry;

2) aging the slurry at 30-200 ℃ for 15 minutes-12 hours;

3) filtering and washing the slurry, and drying a filter cake to obtain the active silica-alumina powder.

Further, the concentration of the water glass in the step 1) is 20-300 g/l based on the dry basis of the silicon oxide.

Further, in the step 1), the concentration of the sodium metaaluminate is 15-150 g/l based on the dry basis of the alumina.

Further, the acid in the step 1) refers to any one or a mixture of sulfuric acid, hydrochloric acid, nitric acid, acetic acid and formic acid, and the pH value of the slurry after the reaction with the acid is 6.0-10.5.

The active silica-alumina powder prepared by the invention mainly comprisesAmorphous silicon oxide and aluminum oxide, and has large specific surface area, which is lower than low temperature N₂The specific adsorption surface area is 120-1000 m²The pore volume is 0.1-2.0 ml/g. The product can be used as a binder or a raw material for producing and preparing catalysts, molecular sieves, adsorbents and the like, can also be directly used for adsorption and decoloration, can also be used for producing silicon-aluminum fibers by hot melting, and can be used for manufacturing refractory and heat-insulating materials.

The invention produces the active silicon-aluminum powder by a chemical method without the working procedures of calcination and the like, has simple production process and low energy consumption, and the produced silicon-aluminum powder has low impurity content, large specific surface area and large pore volume.

Drawings

FIG. 1 is a process flow diagram of the present invention.

Detailed Description

The following description of the embodiments of the present invention will be made with reference to the accompanying drawings, but these examples should not be construed as limiting the scope of the present invention.

The following example of the present invention is to prepare the activated silica-alumina powder of the present invention according to the process flow of fig. 1.

In the embodiment of the invention, the solid water glass is a commercial product, the modulus is 3.2, and the product is produced by Jiangxi Yigao chemical industry development Limited company. Adding deionized water into solid sodium silicate, heating and dissolving to prepare SiO-containing₂A solution in an amount of 200 g/l; and (5) standby.

Solid sodium metaaluminate as a commercial product, Al₂O₃35.3% of Na₂O content of 27.1%, manufactured by Shandong Lier New materials Co. Adding deionized water into solid sodium metaaluminate, heating and dissolving to obtain the invented product containing Al₂O₃A solution in an amount of 120 g/l; and (5) standby.