阅读说明：本技术 一种硅灰石表面涂覆钛酸钠的方法 (Method for coating surface of wollastonite with sodium titanate ) 是由 郭继光 贺炅皓 于 2020-11-21 设计创作，主要内容包括：本申请公开了一种硅灰石表面涂覆钛酸钠的方法,依次包括如下步骤：S1将硅灰石与去离子水按重量比1:5～15加入到搅拌罐中,加入酸调节pH值至3～8之间,经过压滤、水洗、干燥、分级后得到中间过渡体；S2将含钛原料、含钠原料以及所述中间过渡体按重量比0.5～5:1：1～10的比例称量混合,经过球磨机粉碎混合,将混合后的物料转入600～1200℃的高温炉中,煅烧4～8小时,然后以150～200℃/h的降温速率降至室温,经过分级后成为产品,即表面涂覆钛酸钠的硅灰石。本发明在硅灰石表面生长出钛酸钠,形成表面涂覆钛酸钠的硅灰石,可以获得与钛酸钠相近的性能,而制造成本较低。(The application discloses a method for coating wollastonite surface with sodium titanate, which sequentially comprises the following steps: s1, adding wollastonite and deionized water into a stirring tank according to the weight ratio of 1: 5-15, adding acid to adjust the pH value to 3-8, and performing filter pressing, washing, drying and grading to obtain an intermediate transition body; s2, mixing a titanium-containing raw material, a sodium-containing raw material and the intermediate transition body according to a weight ratio of 0.5-5: 1: weighing and mixing the raw materials in a ratio of 1-10, crushing and mixing the raw materials by a ball mill, transferring the mixed materials into a high-temperature furnace at 600-1200 ℃, calcining the materials for 4-8 hours, cooling the materials to room temperature at a cooling rate of 150-200 ℃/h, and grading the materials to obtain a product, namely wollastonite coated with sodium titanate on the surface. The invention grows sodium titanate on the surface of wollastonite to form the wollastonite coated with the sodium titanate on the surface, can obtain the performance similar to the performance of the sodium titanate, and has lower manufacturing cost.)

1. The method for coating the surface of the wollastonite with the sodium titanate is characterized by sequentially comprising the following steps of:

s1, adding wollastonite and deionized water into a stirring tank according to the weight ratio of 1: 5-15, adding acid to adjust the pH value to 3-8, and performing filter pressing, washing, drying and grading to obtain an intermediate transition body;

s2, mixing a titanium-containing raw material, a sodium-containing raw material and the intermediate transition body according to a weight ratio of 0.5-5: 1: weighing and mixing the raw materials in a ratio of 1-10, crushing and mixing the raw materials by a ball mill, transferring the mixed materials into a high-temperature furnace at 600-1200 ℃, calcining the materials for 4-8 hours, cooling the materials to room temperature at a cooling rate of 150-200 ℃/h, and grading the materials to obtain a product, namely wollastonite coated with sodium titanate on the surface.

2. The method for coating the surface of the wollastonite with sodium titanate according to claim 1, wherein the wollastonite has an average particle diameter of 1 to 30 μm and an aspect ratio of 1 to 30.

3. The method for coating the surface of the sodium titanate on the wollastonite as claimed in claim 1, wherein the titanium-containing raw material is one or more of rutile type titanium oxide, anatase type titanium oxide, brookite type titanium oxide or metatitanic acid.

4. The method for coating the surface of the sodium titanate with the wollastonite as set forth in claim 1, wherein the sodium-containing raw material is one or more of sodium hydroxide, sodium carbonate, sodium bicarbonate, sodium nitrate, sodium sulfate and sodium chloride.

5. The method for coating the surface of the sodium titanate on the wollastonite in the claim 1, wherein the sodium titanate coated on the surface of the wollastonite is one or more of sodium trititanate or sodium hexatitanate.

Technical Field

The invention relates to the technical field of sodium titanate with a novel structure, in particular to a method for coating wollastonite surface with sodium titanate.

Background

The sodium titanate has wide application, is mainly used for reinforcing composite materials, modifying engineering plastics, reinforcing ceramics, metals and friction materials, and can also be used for heat-insulating and heat-resisting materials, catalyst carriers, thermal spraying and infrared reflection coatings. Sodium titanate fibers, which are used as friction modifiers in friction materials and do not have carcinogenicity as asbestos, are widely used mainly in brake pads for automobiles. The friction material containing the sodium titanate fiber has the advantages of excellent heat exchange and no loss of the brake disc even if the friction material exerts good braking effect.

Wollastonite is a triclinic system, a fine plate crystal, and aggregates thereof are in a radial or fibrous form. The color is white, sometimes with light grey and light red tones. The glass is glossy, and the cleavage surface is pearl-glossy. 4.5 to 5.5 in hardness and 2.75 to 3.10g/cm3 in density. Wollastonite is an inorganic acicular mineral, and has the characteristics of no toxicity, chemical corrosion resistance, good thermal stability and dimensional stability, glass and pearl luster, low water absorption rate and oil absorption value, excellent mechanical property and electrical property and certain reinforcing effect. The wollastonite product has long fiber length, easy separation, low iron content and high whiteness. The product is mainly used as a reinforcing filler of a high polymer matrix composite material. Such as plastics, rubber, ceramics, paint, building materials and other industries.

Because the raw material price of the sodium titanate is higher, and the price of the finished product of the sodium titanate is also higher, a plurality of automobile brake pad manufacturers cannot use the sodium titanate in large quantities.

Disclosure of Invention

The invention aims to provide a method for coating the surface of wollastonite with sodium titanate.

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

The embodiment of the application discloses a method for coating wollastonite surface with sodium titanate, which sequentially comprises the following steps:

s1, adding wollastonite and deionized water into a stirring tank according to the weight ratio of 1: 5-15, adding acid to adjust the pH value to 3-8, and performing filter pressing, washing, drying and grading to obtain an intermediate transition body;

s2, mixing a titanium-containing raw material, a sodium-containing raw material and the intermediate transition body according to a weight ratio of 0.5-5: 1: weighing and mixing the raw materials in a ratio of 1-10, crushing and mixing the raw materials by a ball mill, transferring the mixed materials into a high-temperature furnace at 600-1200 ℃, calcining the materials for 4-8 hours, cooling the materials to room temperature at a cooling rate of 150-200 ℃/h, and grading the materials to obtain a product, namely wollastonite coated with sodium titanate on the surface.

Preferably, in the method for coating the sodium titanate on the surface of the wollastonite, the wollastonite has an average particle diameter of 1 to 30 μm and an aspect ratio of 1 to 30.

Preferably, in the method for coating the surface of the wollastonite with sodium titanate, the titanium-containing raw material is one or more of rutile titanium oxide, anatase titanium oxide, brookite titanium oxide and metatitanic acid.

Preferably, in the method for coating the surface of the wollastonite with sodium titanate, the sodium-containing raw material is one or more of sodium hydroxide, sodium carbonate, sodium bicarbonate, sodium nitrate, sodium sulfate and sodium chloride.

Preferably, in the method for coating the sodium titanate on the surface of the wollastonite, the sodium titanate coated on the surface of the wollastonite is one or more of sodium trititanate or sodium hexatitanate.

The invention grows sodium titanate on the surface of wollastonite to form the wollastonite coated with the sodium titanate on the surface, can obtain the performance similar to the performance of the sodium titanate, and has lower manufacturing cost.

Drawings

In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings needed to be used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the following description are only some embodiments described in the present application, and other drawings can be obtained by those skilled in the art without creative efforts.

FIG. 1 is a SEM photograph of a product obtained in an embodiment of the present invention;

figure 2 shows the XRD pattern of the product obtained in the example of the present invention.

Detailed Description

Technical solutions in the embodiments of the present invention will be described in detail below, and it is apparent that the described embodiments are only a part of the embodiments of the present invention, and not all embodiments. All other embodiments, which can be obtained by a person skilled in the art without any inventive step based on the embodiments of the present invention, are within the scope of the present invention.

Examples

Wollastonite (with the particle size of 4 microns and the length-diameter ratio of 10) and deionized water are added into a stirring tank according to the weight ratio of 1:9, acid is added to adjust the pH value to be 5, and an intermediate transition body is obtained after filter pressing, water washing, drying and classification.

Mixing a titanium-containing raw material (the titanium-containing raw material is a mixture of rutile titanium oxide with the content of 98% or more and anatase titanium oxide with the content of 98% or more and metatitanic acid, wherein the weight ratio of rutile titanium oxide to anatase titanium oxide to metatitanic acid is 1.5:1:1), a sodium-containing raw material (the sodium-containing raw material is a mixture of sodium carbonate, sodium sulfate and sodium chloride, wherein the weight ratio of sodium carbonate to sodium sulfate to sodium chloride is 3:1:2) and an intermediate transition body according to the weight ratio of 4: 1:5, and then crushing and mixing the mixture by a ball mill. And transferring the mixed raw materials into a high-temperature furnace at 800 ℃, calcining for 7 hours, cooling to room temperature at a cooling rate of 150 ℃/h, and grading to obtain the product, namely wollastonite with the surface coated with sodium titanate, wherein the average particle size is 6 microns.

FIG. 1 is an SEM photograph of an example, and FIG. 2 is an XRD pattern of the example, wherein characteristic peaks of wollastonite and sodium titanate can be clearly seen. After the wollastonite is washed by acid, the surface of the wollastonite is easier to grow sodium titanate, the physical properties of the produced wollastonite coated with the sodium titanate are similar to those of a sodium titanate product, the manufacturing cost is reduced by 30-40%, and the wollastonite can maintain 85% of properties when being equivalently replaced in a brake pad.

The present embodiments are to be considered as illustrative and not restrictive, and the scope of the patent is to be determined by the appended claims.