阅读说明：本技术 一种高纯硅灰石纤维的可控制备方法 (Controllable preparation method of high-purity wollastonite fiber ) 是由 丁文金 陈秋菊 孙红娟 彭同江 于 2019-08-28 设计创作，主要内容包括：本发明涉及一种高纯硅灰石纤维的可控制备方法,包括如下步骤：1)将硅灰石纤维进行粉磨,获得粉末原料；2)将步骤1)获得的粉末原料与浸出助剂进行配料,并置于带搅拌的反应容器中反应,待反应完成后将反应产物固液分离得到固体反应产物和滤液；3)将步骤2)得到的固体反应产物与水进行配料,并添加一定量的分散剂,在液体状体下进行筛分,获得不同粒径的固体产物,将获得的固体产物分别干燥,得到不同长径比的高纯硅灰石纤维。该硅灰石纤维材料具有白度高、补强性能好等特性,可应用于造纸、陶瓷、水泥、橡胶、塑料等行业。(The invention relates to a controllable preparation method of high-purity wollastonite fiber, which comprises the following steps: 1) grinding wollastonite fibers to obtain a powder raw material; 2) mixing the powder raw material obtained in the step 1) with a leaching aid, placing the mixture into a reaction container with a stirrer for reaction, and after the reaction is finished, carrying out solid-liquid separation on a reaction product to obtain a solid reaction product and a filtrate; 3) mixing the solid reaction product obtained in the step 2) with water, adding a certain amount of dispersant, sieving under a liquid state to obtain solid products with different particle sizes, and respectively drying the obtained solid products to obtain the high-purity wollastonite fibers with different length-diameter ratios. The wollastonite fiber material has the characteristics of high whiteness, good reinforcing performance and the like, and can be applied to industries such as papermaking, ceramics, cement, rubber, plastics and the like.)

1. A controllable preparation method of high-purity wollastonite fiber comprises the following steps:

1) grinding natural wollastonite raw materials to obtain wollastonite powder with the average particle size of 40-80 meshes;

2) mixing the wollastonite powder obtained in the step 1) with an auxiliary agent, placing the mixture into a reaction vessel with stirring, and reacting for 30-120 min at the room temperature of-100 ℃ under normal pressure to obtain a reaction product;

3) and (3) carrying out suction filtration and washing on the reaction product obtained in the step 2) to obtain a solid product and a filtrate.

2. A controllable preparation method of high-purity wollastonite fiber comprises the following steps:

1) taking a certain mass of the solid product, adding a certain amount of water and a dispersant, fully stirring, and sieving at normal pressure and room temperature of-150 ℃ to obtain solid products with different particle sizes;

2) respectively washing and drying the products obtained in the step 1) to obtain high-purity wollastonite fiber materials with different length-diameter ratios; the screened filtrate can be recycled.

3. The method of claim 1, wherein:

the content of calcium silicate in the natural wollastonite raw material in the step 1) is more than 90 percent; in the step 2), the auxiliary agent is one or more of acetic acid, hydrochloric acid and oxalic acid; the concentration of the auxiliary agent is 0.1-3 mol/L; the addition amount of the leaching aid is 3-25 mL/g.

4. The method of claim 2, wherein:

the adding amount of the water in the step 1) is 5-30 mL/g; the dispersing agent is one or more of sodium sulfonate and sodium humate, and the addition amount of the dispersing agent is 1-10% of the mass of the solid product.

5. The production method according to claims 1 to 4, characterized in that:

in the controllable preparation process of the high-purity wollastonite fiber, natural wollastonite is used as a raw material, the process is simple, only a small amount of chemical additives are needed to be added, the additives can be recycled, and the whole preparation process is finished at low temperature and normal pressure; the content of calcium silicate in the wollastonite fiber is more than 98%, the length-diameter ratio of the fiber is controllable, and the whiteness is more than 95.

Technical Field

The invention relates to a controllable preparation method of high-purity wollastonite fibers, in particular to a method for extracting wollastonite fibers and controlling the length-diameter ratio of the wollastonite fibers, and belongs to the field of inorganic functional materials.

Background

Wollastonite is a functional mineral material with a high refractive index and a long fiber structure, has the advantages of good insulativity and dielectric property, good thermal stability and dimensional stability, excellent mechanical reinforcing effect and the like, and is widely applied to the fields of coatings, plastics, rubber, papermaking, ceramics and the like.

The naturally produced wollastonite often generates impurities such as carbonate which affect the quality of the wollastonite, and the wollastonite has a fibrous morphology and has similar beneficiation characteristics to the calcite, so that the impurities such as the carbonate are difficult to remove from the wollastonite raw ore by the common mineral processing method.

The length-diameter ratio of wollastonite in natural products is different, selective application of wollastonite is not utilized, wollastonite fibers can be controlled and prepared to be beneficial to ladder-type application of wollastonite fiber materials, and the added value of the overall utilization of the wollastonite fiber materials is improved.

In conclusion, the invention provides a novel method for purifying wollastonite and regulating the length-diameter ratio of wollastonite fibers, which takes natural wollastonite as a raw material, has low cost and simple operation.

Disclosure of Invention

The invention aims to provide a method for purifying wollastonite and regulating the length-diameter ratio of wollastonite, which has the advantages of simple process and low cost.

In order to achieve the above object, the present invention adopts the following technical solutions.

A controllable preparation method of high-purity wollastonite fiber comprises the following steps:

1) grinding natural wollastonite raw materials to obtain wollastonite powder with the average particle size of 40-80 meshes;

2) mixing the wollastonite powder obtained in the step 1) with an auxiliary agent, placing the mixture into a reaction vessel with stirring, and reacting for 30-120 min at the room temperature of-100 ℃ under normal pressure to obtain a reaction product;

3) carrying out suction filtration and washing on the reaction product obtained in the step 2) to obtain a solid product and a filtrate;

4) taking a certain mass of the reaction product obtained in the step 3), adding a certain amount of water and a dispersant, fully stirring, and sieving at normal pressure and room temperature of-150 ℃ to obtain solid products with different particle sizes;

5) washing and drying the products obtained in the step 4) respectively to obtain high-purity wollastonite fiber materials with different length-diameter ratios; the screened filtrate can be recycled.

The content of calcium silicate in the natural wollastonite raw material in the step 1) is more than 90 percent; in the step 2), the auxiliary agent is one or more of acetic acid, hydrochloric acid and oxalic acid; the concentration of the auxiliary agent is 0.1-3 mol/L; the addition amount of the leaching aid is 3-25 mL/g.

The addition amount of the water in the step 4) is 5-30 mL/g; the dispersing agent is one or more of sodium sulfonate and sodium humate, and the addition amount of the dispersing agent is 1-10% of the mass of the solid product.

The wollastonite fiber prepared by the method has the calcium silicate content of more than 98 percent, the length-diameter ratio of the fiber is controllable, and the whiteness is more than 95.

The method for preparing the high-purity wollastonite fiber material with different length-diameter ratios has the following beneficial effects: 1) the raw material used in the invention is natural wollastonite, and is easy to obtain; 2) the whole process is carried out at low temperature and normal pressure, and is safe; 3) the dispersant can be recycled; 5) the purity of the prepared wollastonite fiber material can reach more than 98 percent, the whiteness is more than 95, and the length-diameter ratio is controllable on the premise of reducing the dosage of chemical additives and shortening the production period by using the method disclosed by the invention.

Detailed Description

The invention relates to a controllable preparation method of high-purity wollastonite fiber, which comprises the following steps.

1) Grinding natural wollastonite raw materials to obtain wollastonite powder with the average particle size of 40-80 meshes;

wherein, the content of calcium silicate in the natural wollastonite raw material in the step 1) is more than 90 percent.

2) Mixing the wollastonite powder obtained in the step 1) with an auxiliary agent, placing the mixture into a reaction vessel with stirring, and reacting for 30-120 min at the room temperature of-100 ℃ under normal pressure to obtain a reaction product;

wherein, the auxiliary agent in the step 2) is one or more of acetic acid, hydrochloric acid and oxalic acid; the concentration of the auxiliary agent is 0.1-3 mol/L; the addition amount of the leaching aid is 3-25 mL/g.

3) And (3) carrying out suction filtration and washing on the reaction product obtained in the step 2) to obtain a solid product and a filtrate.

4) Taking a certain mass of the reaction product obtained in the step 3), adding a certain amount of water and a dispersant, fully stirring, and sieving at normal pressure and room temperature of-150 ℃ to obtain solid products with different particle sizes;

wherein the addition amount of the water in the step 4) is 5-30 mL/g; the dispersing agent is one or more of sodium sulfonate and sodium humate, and the addition amount of the dispersing agent is 1-10% of the mass of the solid product.

5) Washing and drying the products obtained in the step 4) respectively to obtain high-purity wollastonite fiber materials with different length-diameter ratios; the screened filtrate can be recycled.

The wollastonite fiber prepared by the method has the calcium silicate content of more than 98 percent, the length-diameter ratio of the fiber is controllable, and the whiteness is more than 95.

The technical solution of the present invention is further described in detail by the following specific examples.

Example 1:

the main chemical components of the wollastonite in this example are, in weight percent: CaO46%, SiO₂52%, the other 2%; the specific process comprises the following steps:

1) taking 100g of the 50-mesh wollastonite powder, preparing 830 mL of 0.1 mol/L hydrochloric acid solution, then pouring the wollastonite powder into the hydrochloric acid solution, stirring and reacting at room temperature for 55 min, and after the reaction is finished, performing suction filtration to obtain a filtrate and a solid reactant;

2) taking 50 g of the solid reaction product, adding 650 mL of tap water and 8 g of sodium hexadecylbenzene sulfonate, stirring uniformly at 100 ℃, and screening; obtaining wollastonite fibers with different particle sizes, respectively washing and drying products to obtain high-purity wollastonite fibers with different length-diameter ratios;

3) the wollastonite fiber material obtained by the method has 99.6 percent of wollastonite and controllable length-diameter ratio.

Example 2

The main chemical components of the wollastonite in this example are, in weight percent: CaO48%, SiO₂50%, the other 2%; the specific process comprises the following steps:

1) taking 80g of the 60-mesh wollastonite powder, preparing 760 mL of 0.1 mol/L acetic acid solution, then pouring the wollastonite powder into the acetic acid solution, stirring and reacting for 85 min at 75 ℃, and after the reaction is finished, performing suction filtration to obtain filtrate and a solid reactant;

2) taking 60 g of the solid reaction product, adding 540 mL of tap water, adding 3 g of sodium hexadecylbenzene sulfonate and 2 g of sodium hexadecylsulfate, stirring uniformly at 80 ℃, and screening; obtaining wollastonite fibers with different particle sizes, respectively washing and drying products to obtain high-purity wollastonite fibers with different length-diameter ratios;

3) the wollastonite fiber material obtained by the method has the wollastonite content of 98.7 percent and the length-diameter ratio is controllable.