阅读说明：本技术 一种利用钛白粉副产物制备3d打印材料的方法 (Method for preparing 3D printing material by using titanium dioxide byproduct ) 是由 王敏 于 2019-10-14 设计创作，主要内容包括：本发明的一种利用钛白粉副产物制备3D打印材料的方法。本发明将将钛白粉副产物加入纯水溶解,加入酸碱调节溶液的pH,升温后加入镍粉反应至溶液的pH为4-5.5,然后加入硅藻土和絮凝剂,搅拌絮凝15-30min,然后过滤,得到滤液和滤渣；将滤液、氨水、草酸铵同时对加到底液中,维持溶液的pH为6-7,加料后继续搅拌反应,然后过滤、洗涤,得到沉淀颗粒；沉淀颗粒加入草酸铵溶液和分散剂,然后搅拌分散,经过喷雾干燥得到喷雾干燥料,放入还原炉中进行氨气还原,将还原料经过气流粉碎,然后进行分级、筛分,得到3D打印材料。本发明工艺简单,能够得到分散性和流动性好,粒度分布窄的3D打印金属粉末材料。(The invention discloses a method for preparing a 3D printing material by using a titanium dioxide byproduct. Dissolving a titanium dioxide byproduct in pure water, adding acid and alkali to adjust the pH value of the solution, heating, adding nickel powder to react until the pH value of the solution is 4-5.5, adding diatomite and a flocculating agent, stirring and flocculating for 15-30min, and filtering to obtain a filtrate and filter residues; simultaneously adding the filtrate, ammonia water and ammonium oxalate into the base solution, maintaining the pH of the solution at 6-7, continuously stirring for reaction after adding the solution, and then filtering and washing to obtain precipitate particles; adding an ammonium oxalate solution and a dispersing agent into the precipitated particles, stirring and dispersing, performing spray drying to obtain a spray-dried material, performing ammonia reduction in a reduction furnace, performing jet milling on the reduced material, and performing classification and screening to obtain the 3D printing material. The method is simple in process, and the 3D printing metal powder material with good dispersity and fluidity and narrow particle size distribution can be obtained.)

1. A method for preparing a 3D printing material by using a titanium dioxide byproduct is characterized by comprising the following steps:

(1) dissolving the titanium dioxide byproduct in pure water, adding an acid-base adjusting solution with the pH of 1.2-1.5, heating to 60-80 ℃, adding nickel powder to react until the pH of the solution is 4-5.5, then adding diatomite and a flocculating agent, stirring and flocculating for 15-30min, and then filtering to obtain a filtrate and filter residues;

(2) adding the filtrate, ammonia water and ammonium oxalate into the base solution simultaneously, maintaining the pH of the solution at 6-7, the temperature at 45-60 deg.C, the feeding speed at 6-9h, continuously stirring for reaction for 30-60min after feeding, filtering, and washing to obtain precipitate particles;

(3) adding the precipitated particles obtained in the step (2) into an ammonium oxalate solution and a dispersing agent, stirring and dispersing, and performing spray drying to obtain a spray-dried material;

(4) putting the dried material obtained in the step (3) into a reduction furnace for ammonia reduction at the reduction temperature of 450 ℃ and 750 ℃ for 6-10h, and cooling to obtain a reduced material;

(5) and (3) crushing the reducing material by airflow, and then grading and screening to obtain the 3D printing material.

2. The method for preparing the 3D printing material by using the titanium dioxide byproduct according to claim 1, wherein the mass ratio of the titanium dioxide byproduct to pure water in the step (1) is 1:4-5, the iron content in the titanium dioxide byproduct is more than 18%, the particle size of the added nickel powder is less than 20 μm, and the mass ratio of the added diatomite, the flocculant and the titanium dioxide byproduct is 1-2: 0.1-0.2: 1000.

3. the method for preparing 3D printing material by using titanium dioxide byproduct according to claim 1, wherein the method comprises the following steps: drying and crushing the filter residue obtained in the step (1), sieving the filter residue with a 100-mesh sieve, performing magnetic separation, returning the obtained magnetic separation material to be mixed with nickel powder for use, calcining the mixed material subjected to magnetic separation with alkali at the calcining temperature of 300-500 ℃ for 3-4h, crushing and then washing with water to obtain a sodium metatitanate solution, introducing carbon dioxide until the titanium content in the solution is lower than 50mg/L, filtering, washing the obtained precipitate with water and then calcining at the high temperature of 850-950 ℃ to obtain the nano titanium dioxide.

4. The method for preparing 3D printing material by using titanium dioxide byproduct according to claim 1, wherein the method comprises the following steps: in the step (2), the molar ratio of iron to ammonium oxalate in the added filtrate is 1:0.9-0.95, and ammonia water is added to adjust and maintain the pH value of the solution.

5. The method for preparing 3D printing material by using titanium dioxide byproduct according to claim 1, wherein the method comprises the following steps: the mass ratio of the precipitated particles in the step (3) to the ammonium oxalate in the ammonium oxalate solution is 20-30: 1: 0.1 to 0.2 percent, the dispersant is polyethylene glycol 2000, the concentration of the ammonium oxalate solution is 0.2 to 0.5mol/L, the inlet air temperature in the spray drying process is 200 ℃ and 230 ℃, and the outlet temperature is less than 80 ℃.

6. The method for preparing 3D printing material by using titanium dioxide byproduct according to claim 1, wherein the method comprises the following steps: in the step (4), the volume of the ammonia gas introduced per hour is 5-10 times of the volume of the reduction furnace.

7. The method for preparing 3D printing material by using titanium dioxide byproduct according to claim 1, wherein the method comprises the following steps: in the step (5), the airflow crushing adopts 0.4-0.6MPa nitrogen as a gas source, the crushed material is classified by a classification wheel to obtain particles with D50 of 2-4 mu m, and then the particles are sieved by a 250-350-mesh ultrasonic vibration sieve.

Technical Field

The invention relates to a method for preparing a 3D printing material by using a titanium dioxide byproduct, and belongs to the technical field of 3D printing.

Background

The 3D printing is a technology for manufacturing a three-dimensional product by adding materials layer by layer through a 3D printing apparatus according to a designed 3D model, and it will become the next sunrise industry with a wide development prospect.

The material that 3D printed has more than 30, contains SLA photosensitive resin, SLS nylon (glass fiber), full-color printing, PLA (flexibility, xylon), metal (stainless steel, aluminum alloy), red blue wax and flexible glue, engineering PC, ABS material, materials such as silica gel compound mould. The printing range covers more industries and various requirements, and comprises the fields of various product hand-plate proofs, jewelry, industrial design, casting, medical treatment, glasses, automobile electronics, aerospace, cultural creativity, emerging industries and the like.

The particle size of the generally used powdery 3D printing material varies from 1 to 100 micrometers, and the powder is generally required to have a high sphericity in order to maintain good flowability of the powder.

However, the conventional metal 3D printing material has the defects of poor dispersibility, poor flowability and wider particle size distribution.

Disclosure of Invention

The invention provides a method for preparing a 3D printing material by using a titanium dioxide byproduct, which is simple in process and can obtain a 3D printing metal powder material with good dispersibility and fluidity and narrow particle size distribution.

The technical scheme adopted by the invention for solving the technical problems is as follows:

a method for preparing a 3D printing material by using a titanium dioxide byproduct comprises the following steps:

(1) dissolving the titanium dioxide byproduct in pure water, adding an acid-base adjusting solution with the pH of 1.2-1.5, heating to 60-80 ℃, adding nickel powder to react until the pH of the solution is 4-5.5, then adding diatomite and a flocculating agent, stirring and flocculating for 15-30min, and then filtering to obtain a filtrate and filter residues;

(2) adding the filtrate, ammonia water and ammonium oxalate into the base solution simultaneously, maintaining the pH of the solution at 6-7, the temperature at 45-60 deg.C, the feeding speed at 6-9h, continuously stirring for reaction for 30-60min after feeding, filtering, and washing to obtain precipitate particles;

(3) adding the precipitated particles obtained in the step (2) into an ammonium oxalate solution and a dispersing agent, stirring and dispersing, and performing spray drying to obtain a spray-dried material;

(4) putting the dried material obtained in the step (3) into a reduction furnace for ammonia reduction at the reduction temperature of 450 ℃ and 750 ℃ for 6-10h, and cooling to obtain a reduced material;

(5) and (3) crushing the reducing material by airflow, and then grading and screening to obtain the 3D printing material.

In the step (1), the mass ratio of the titanium dioxide byproduct to the pure water is 1:4-5, the iron content in the titanium dioxide byproduct is more than 18%, the particle size of the added nickel powder is less than 20 μm, and the mass ratio of the added diatomite, the flocculant and the titanium dioxide byproduct is 1-2: 0.1-0.2: 1000.

drying and crushing the filter residue obtained in the step (1), sieving the filter residue with a 100-mesh sieve, performing magnetic separation, returning the obtained magnetic separation material to be mixed with nickel powder for use, calcining the mixed material subjected to magnetic separation with alkali at the calcining temperature of 300-500 ℃ for 3-4h, crushing and then washing with water to obtain a sodium metatitanate solution, introducing carbon dioxide until the titanium content in the solution is lower than 50mg/L, filtering, washing the obtained precipitate with water and then calcining at the high temperature of 850-950 ℃ to obtain the nano titanium dioxide.

In the step (2), the molar ratio of iron to ammonium oxalate in the added filtrate is 1:0.9-0.95, and ammonia water is added to adjust and maintain the pH value of the solution.

The mass ratio of the precipitated particles in the step (3) to the ammonium oxalate in the ammonium oxalate solution is 20-30: 1: 0.1 to 0.2 percent, the dispersant is polyethylene glycol 2000, the concentration of the ammonium oxalate solution is 0.2 to 0.5mol/L, the inlet air temperature in the spray drying process is 200 ℃ and 230 ℃, and the outlet temperature is less than 80 ℃.

In the step (4), the volume of the ammonia gas introduced per hour is 5-10 times of the volume of the reduction furnace.

In the step (5), the airflow crushing adopts 0.4-0.6MPa nitrogen as a gas source, the crushed material is classified by a classification wheel to obtain particles with D50 of 2-4 mu m, and then the particles are sieved by a 250-350-mesh ultrasonic vibration sieve.

The invention can greatly reduce the cost by taking the titanium dioxide byproduct as the raw material, then improve the pH of the solution by reducing and dissolving the nickel powder, simultaneously replace partial impurities, such as copper, and precipitate titanium plasma in the solution, and simultaneously control the initial pH and the final pH to control the content of nickel.

Then adding the ferrous solution, ammonia water and ammonium oxalate into the base solution simultaneously, maintaining the pH of the solution at 6-7 and the temperature at 45-60 ℃, and obtaining large-particle spherical ferric salt precipitate by a horizontal adding mode, and simultaneously obtaining basic salt precipitate by the molar ratio of iron to ammonium oxalate in the filtrate of the invention being 1:0.9-0.95, and obtaining basic salt precipitate with higher compactness and sphericity by the complexation of ammonia.

Then, washing to obtain precipitate particles, adding an ammonium oxalate solution and a dispersing agent into the precipitate particles, then, carrying out spray drying to obtain particles coated by the ammonium oxalate and the dispersing agent, then, reducing the particles by a reducing furnace, decomposing the ammonium oxalate to obtain partial carbon monoxide in the atmosphere of ammonia gas, simultaneously, generating partial carbon by the dispersing agent in the thermal decomposition process, carrying out reduction reaction on the carbon monoxide and the carbon and the precipitate particles to obtain elemental iron and nickel, and catalytically decomposing ammonia by the obtained nickel to obtain nitrogen and hydrogen, so that more precipitate particles are reacted to obtain the elemental iron and nickel, and the reduction reaction is realized.

Meanwhile, the surfaces of the precipitated particles are coated with ammonium oxalate and a dispersing agent, so that ammonia gas, carbon dioxide, carbon monoxide, water vapor and the like are generated in the high-temperature thermal decomposition process, and the adjacent particles can be effectively prevented from agglomerating and growing to obtain high-dispersity powder particles.

The indexes of the 3D printing material obtained by the invention are as follows:

the invention has the beneficial effects that: the process is simple, and the 3D printing metal powder material with good dispersity and fluidity and narrow particle size distribution can be obtained.

Drawings

FIG. 1 is an SEM of precipitated particles obtained in example 1 of the present invention.

Fig. 2 is an SEM of the 3D printed material obtained in example 1 of the present invention.

FIG. 3 is an SEM of the nano titanium dioxide obtained in example 1 of the present invention.

Detailed Description

The present invention will now be described in further detail with reference to specific embodiments thereof.

The present invention is further illustrated by the following examples, which are not to be construed as limiting the invention.

A method for preparing a 3D printing material by using a titanium dioxide byproduct comprises the following steps:

(1) dissolving the titanium dioxide byproduct in pure water, adding an acid-base adjusting solution with the pH of 1.2-1.5, heating to 60-80 ℃, adding nickel powder to react until the pH of the solution is 4-5.5, then adding diatomite and a flocculating agent, stirring and flocculating for 15-30min, and then filtering to obtain a filtrate and filter residues;

(2) adding the filtrate, ammonia water and ammonium oxalate into the base solution simultaneously, maintaining the pH of the solution at 6-7, the temperature at 45-60 deg.C, the feeding speed at 6-9h, continuously stirring for reaction for 30-60min after feeding, filtering, and washing to obtain precipitate particles;

(3) adding the precipitated particles obtained in the step (2) into an ammonium oxalate solution and a dispersing agent, stirring and dispersing, and performing spray drying to obtain a spray-dried material;

(4) putting the dried material obtained in the step (3) into a reduction furnace for ammonia reduction at the reduction temperature of 450 ℃ and 750 ℃ for 6-10h, and cooling to obtain a reduced material;

(5) and (3) crushing the reducing material by airflow, and then grading and screening to obtain the 3D printing material.

In the step (1), the mass ratio of the titanium dioxide byproduct to the pure water is 1:4-5, the iron content in the titanium dioxide byproduct is more than 18%, the particle size of the added nickel powder is less than 20 μm, and the mass ratio of the added diatomite, the flocculant and the titanium dioxide byproduct is 1-2: 0.1-0.2: 1000.

drying and crushing the filter residue obtained in the step (1), sieving the filter residue with a 100-mesh sieve, performing magnetic separation, returning the obtained magnetic separation material to be mixed with nickel powder for use, calcining the mixed material subjected to magnetic separation with alkali at the calcining temperature of 300-500 ℃ for 3-4h, crushing and then washing with water to obtain a sodium metatitanate solution, introducing carbon dioxide until the titanium content in the solution is lower than 50mg/L, filtering, washing the obtained precipitate with water and then calcining at the high temperature of 850-950 ℃ to obtain the nano titanium dioxide.

In the step (2), the molar ratio of iron to ammonium oxalate in the added filtrate is 1:0.9-0.95, and ammonia water is added to adjust and maintain the pH value of the solution.

The mass ratio of the precipitated particles in the step (3) to the ammonium oxalate in the ammonium oxalate solution is 20-30: 1: 0.1 to 0.2 percent, the dispersant is polyethylene glycol 2000, the concentration of the ammonium oxalate solution is 0.2 to 0.5mol/L, the inlet air temperature in the spray drying process is 200 ℃ and 230 ℃, and the outlet temperature is less than 80 ℃.

In the step (4), the volume of the ammonia gas introduced per hour is 5-10 times of the volume of the reduction furnace.

In the step (5), the airflow crushing adopts 0.4-0.6MPa nitrogen as a gas source, the crushed material is classified by a classification wheel to obtain particles with D50 of 2-4 mu m, and then the particles are sieved by a 250-350-mesh ultrasonic vibration sieve.