A method for producing calcined talc powder for high-whiteness building materials using black talc

Abstract

The invention relates to the technical field of building materials, and discloses a method for producing calcined talc powder for high-whiteness building materials by using black talc. The method comprises the following steps: pickling the black talc ore powder in a hydrochloric acid or nitric acid system, rinsing the black talc ore powder with sodium dithionite, flotation purification in a flotation system of fatty alcohol polyoxyethylene ether sulfonate, fatty alcohol ether phosphate MOA-3P, etc., and finally calcining the talc powder to obtain a talc powder with a whiteness of 90.3-95.2% and a talc content of 86.4-93.5%. The scheme of the invention is used in building materials, so as to realize resource utilization of the black talc ore and significantly improve the quality of the talc powder.

Description

Technical Field

[0001] The invention relates to the technical field of building materials, in particular to a method for producing calcined talc powder for high-whiteness building materials by utilizing black talc. Background Art

[0002] Black talc is a magnesium-rich silicate mineral, the main components of which are silicon dioxide, magnesium oxide, aluminum oxide, iron oxide, etc. It is abundant in reserves and cheap and easy to obtain. Whiteness is an important technical indicator of talc quality. High-whiteness talc is widely used in white or colored plastics, coatings, putty powder and other fields. Due to the low whiteness and black color of black talc, the appearance of materials and products is seriously affected, resulting in a large restriction on the practical application of black talc. In order to expand the application field of black talc, it is necessary to improve its whiteness. The invention patent with announcement number CN100577607C, IPC classification number C04B35 / 626 and name "Process for making high-white ultrafine talc powder from black talc" discloses that the talc obtained by using black talc mineral as raw material through ore dressing, crushing, grinding, calcining, iron removal, breaking and grading processes has the advantages of high whiteness and small particle size. High-performance talc is widely used in the field of building materials. The invention patent with publication number CN116354743A, IPC classification number C04B41 / 68, and titled "A water-based penetrating crystallization waterproofing agent and its preparation method" discloses that modified fine talc powder, penetrating crystallization components, etc. are used as the main components of the waterproofing agent, which has good practical applications in building materials such as concrete. Although my country has abundant talc reserves, most of them are low-grade talc ores with low talc content, many types of impurity minerals, and complex associated structures. Therefore, it is necessary to select and beneficiate the talc ores. The present invention aims to use black talc as raw material, adopt acid washing, rinsing, flotation and calcination processes, and obtain high-whiteness and high-grade talc powder. Summary of the invention

[0003] The technical problem solved by the invention is to provide a method for producing calcined talc powder for high-whiteness building materials by using black talc, thereby solving the problems of low whiteness and low talc content of talc powder.

[0004] The technical solution provided by the present invention is: a method for producing calcined talc powder for high-whiteness building materials using black talc, comprising the following steps:

[0005] (1) Crushing the black talc into particles and adding them into acid solution for pickling.

[0006] (2) Filter the acid solution, wash with water, then disperse the black talcum powder in water and add sodium dithionite for rinsing.

[0007] (3) After rinsing, filter and wash with water. Place the washed talc in a flotation machine, add water, collector, additive, frother and sodium hydroxide to prepare ore slurry, and perform positive flotation. After flotation purification, dry and dehydrate the ore slurry.

[0008] (4) The dried and dehydrated talc powder is placed in a feed bin and stirred and dispersed, then pressed into shape by a hydraulic press, placed on a pad by a suction cup and transported to a roller kiln, fired in a roller kiln, and then crushed and ball-milled in a continuous ball mill to obtain calcined talc powder for high-whiteness building materials.

[0009] Preferably, the black talc in (1) is crushed into particles with a particle size of 100-200 mesh.

[0010] Preferably, (1) the neutral acid solution is a hydrochloric acid solution with a mass fraction of 15-25%, or a nitric acid solution with a mass fraction of 20-35%.

[0011] Preferably, the mass of sodium dithionite in (2) is 10-30% of the mass of black talc.

[0012] Preferably, the rinsing temperature in (2) is 20-35°C and the rinsing time is 4-10 hours.

[0013] Preferably, the amount of collector in (3) is 0.2-0.5% of the mass of talc.

[0014] Preferably, the collector is any one of sodium dodecylbenzene sulfonate, sodium dodecyl sulfate, sodium dodecyl sulfonate, and fatty alcohol polyoxyethylene ether sulfonate.

[0015] Preferably, the amount of the auxiliary agent in (3) is 0.1-0.3% of the mass of talc.

[0016] Preferably, the auxiliary agent is fatty alcohol ether phosphate MOA-3P or phenol ether phosphate potassium salt NP-10PK40.

[0017] Preferably, sodium hydroxide is added in (3) to adjust the pH of the flotation ore slurry to 8-10.

[0018] Preferably, the firing temperature in (3) is 1050-1190° C. and the firing time is 5-7 h.

[0019] The technical effect is as follows: the present invention is used in the field of building materials, the black talc ore powder of the present invention is pickled in a hydrochloric acid or nitric acid system, rinsed with sodium dithionite, and flotated and purified in a flotation system of fatty alcohol polyoxyethylene ether sulfonate, fatty alcohol ether phosphate MOA-3P, etc., to reduce impurity minerals in the talc ore, optimize the associated structure, and finally after high-temperature sintering, the whiteness of the obtained talc powder is 90.3-95.2%, and the talc content reaches 86.4-93.5%; the scheme of the present invention is used in building materials, realizes the resource utilization of black talc ore, and significantly improves the quality of talc powder. DETAILED DESCRIPTION

[0020] The technical solutions in the embodiments of the present invention are described clearly and completely below. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0021] Example 1

[0022] (1) 1 kg of black talc was crushed into particles with a particle size of 100-200 mesh, then added into 5 L of 20% hydrochloric acid solution and pickled at 25 °C for 1 h.

[0023] (2) Filter the acid solution, wash with water, then disperse 1 kg of black talcum powder in 5 L of water, add 0.25 kg of sodium dithionite, and rinse at 35°C for 4 hours.

[0024] (3) After rinsing, filter and wash with water. Place 1 kg of the washed talc in a flotation machine, add 3 L of water, 2 g of collector fatty alcohol polyoxyethylene ether sulfonate FXS, 3 g of auxiliary fatty alcohol ether phosphate MOA-3P, and 0.5 g of frother (brand KF-F1), add sodium hydroxide to control the pH of the slurry to 10, and perform positive flotation. After flotation purification, dry and dehydrate the slurry.

[0025] (4) The dried and dehydrated talcum powder is placed in a feed bin and stirred and dispersed, then pressed into shape by an automatic hydraulic press, placed on a pad via a sponge suction cup and transported to a roller kiln, fired in a roller kiln at 1050°C for 6 hours, then crushed and ball-milled in an automatic continuous ball mill to obtain calcined talcum powder for high-whiteness building materials.

[0026] Example 2

[0027] (1) 1 kg of black talc was crushed into particles with a particle size of 100-200 mesh, then added into 5 L of 35% nitric acid solution and pickled at 25 °C for 1 h.

[0028] (2) Filter the acid solution, wash with water, then disperse 1 kg of black talcum powder in 5 L of water, add 0.3 kg of sodium dithionite, and rinse at 20°C for 10 h.

[0029] (3) After rinsing, filter and wash with water. Place 1 kg of the washed talc powder in a flotation machine, add 3 L of water, 3.8 g of collector sodium dodecylbenzene sulfonate, 1 g of auxiliary agent phenol ether phosphate potassium salt NP-10PK40, and 0.8 g of frother (brand KF-F1), add sodium hydroxide to control the pH of the ore slurry to 10, and perform positive flotation. After flotation purification, dry and dehydrate the ore slurry.

[0030] (4) The dried and dehydrated talcum powder is placed in a feed bin and stirred and dispersed, then pressed into shape by an automatic hydraulic press, placed on a pad via a sponge suction cup and transported to a roller kiln, fired in a roller kiln at 1050°C for 7 hours, then crushed and ball-milled in an automatic continuous ball mill to obtain calcined talcum powder for high-whiteness building materials.

[0031] Example 3

[0032] (1) 1 kg of black talc was crushed into particles with a particle size of 100-200 mesh, then added into 5 L of 15% hydrochloric acid solution and pickled at 25 °C for 2 h.

[0033] (2) Filter the acid solution, wash with water, then disperse 1 kg of black talcum powder in 5 L of water, add 0.1 kg of sodium dithionite, and rinse at 25°C for 10 hours.

[0034] (3) After rinsing, filter and wash with water. Place 1 kg of the washed talc in a flotation machine, add 3 L of water, 5 g of collector fatty alcohol polyoxyethylene ether sulfonate FXS, 1.5 g of auxiliary fatty alcohol ether phosphate MOA-3P, and 0.4 g of frother (brand KF-F1), add sodium hydroxide to control the pH of the slurry to 8, and perform positive flotation. After flotation purification, dry and dehydrate the slurry.

[0035] (4) The dried and dehydrated talcum powder is placed in a feed bin and stirred and dispersed, then pressed into shape by an automatic hydraulic press, placed on a pad via a sponge suction cup and transported to a roller kiln, fired in a roller kiln at 1190°C for 5 hours, then crushed and ball-milled in an automatic continuous ball mill to obtain calcined talcum powder for high-whiteness building materials.

[0036] Example 4

[0037] (1) 1 kg of black talc was crushed into particles with a particle size of 100-200 mesh, then added into 5 L of 20% nitric acid solution and pickled at 25 °C for 1 h.

[0038] (2) Filter the acid solution, wash with water, then disperse 1 kg of black talcum powder in 5 L of water, add 0.3 kg of sodium dithionite, and rinse at 25°C for 8 h.

[0039] (3) After rinsing, filter and wash with water. Place 1 kg of the washed talc powder in a flotation machine, add 3 L of water, 4 g of collector sodium dodecyl sulfate, 2.2 g of auxiliary agent phenol ether phosphate potassium salt NP-10PK40, and 0.4 g of frother (brand KF-F1). Add sodium hydroxide to control the pH of the ore slurry to 10, and perform positive flotation. After flotation purification, dry and dehydrate the ore slurry.

[0040] (4) The dried and dehydrated talcum powder is placed in a feed bin and stirred and dispersed, then pressed into shape by an automatic hydraulic press, placed on a pad via a sponge suction cup and transported to a roller kiln, fired in a roller kiln at 1050°C for 4 hours, then crushed and ball-milled in an automatic continuous ball mill to obtain calcined talcum powder for high-whiteness building materials.

[0041] Example 5

[0042] (1) 1 kg of black talc was crushed into particles with a particle size of 100-200 mesh, then added into 5 L of 25% hydrochloric acid solution and pickled at 25 °C for 1 h.

[0043] (2) Filter the acid solution, wash with water, then disperse 1 kg of black talcum powder in 5 L of water, add 0.25 kg of sodium dithionite, and rinse at 20°C for 8 h.

[0044] (3) After rinsing, filter and wash with water. Place 1 kg of the washed talc in a flotation machine, add 3 L of water, 2.8 g of collector sodium dodecyl sulfate, 1.5 g of auxiliary agent phenol ether phosphate potassium salt NP-10PK40, and 0.4 g of frother (brand KF-F1). Add sodium hydroxide to control the pH of the ore slurry to 10, and perform positive flotation. After flotation purification, dry and dehydrate the ore slurry.

[0045] (4) The dried and dehydrated talcum powder is placed in a feed bin and stirred and dispersed, then pressed into shape by an automatic hydraulic press, placed on a pad via a sponge suction cup and transported to a roller kiln, fired in a roller kiln at 1100°C for 6 hours, then crushed and ball-milled in an automatic continuous ball mill to obtain calcined talcum powder for high-whiteness building materials.

[0046] Comparative Example 1

[0047] (1) 1 kg of black talc was crushed into particles with a particle size of 100-200 mesh, then added into 5 L of 20% hydrochloric acid solution and pickled at 25 °C for 1 h.

[0048] (2) After acid washing, filter and wash with water. Place 1 kg of the washed talc in a flotation machine, add 3 L of water, 2 g of collector fatty alcohol polyoxyethylene ether sulfonate, 3 g of auxiliary fatty alcohol ether phosphate MOA-3P, and 0.5 g of frother (brand KF-F1), add sodium hydroxide to control the pH of the slurry to 10, and perform positive flotation. After flotation purification, dry and dehydrate the slurry.

[0049] (3) The dried and dehydrated talcum powder is placed in a feed bin and stirred and dispersed, then pressed into shape by an automatic hydraulic press, placed on a pad via a sponge suction cup and transported to a roller kiln, fired in a roller kiln at 1050°C for 6 hours, then crushed and ball-milled in an automatic continuous ball mill to obtain calcined talcum powder for high-whiteness building materials.

[0050] Comparative Example 2

[0051] (1) Crush 1 kg of black talc into particles with a particle size between 100 and 200 mesh, disperse into 5 L of water, add 0.25 kg of sodium dithionite, and rinse at 35 °C for 4 h.

[0052] (2) After rinsing, filter and wash with water. Place 1 kg of the washed talc in a flotation machine, add 3 L of water, 2 g of collector fatty alcohol polyoxyethylene ether sulfonate, 3 g of auxiliary fatty alcohol ether phosphate MOA-3P, and 0.5 g of frother (brand KF-F1), add sodium hydroxide to control the pH of the slurry to 10, and perform positive flotation. After flotation purification, dry and dehydrate the slurry.

[0053] (3) The dried and dehydrated talcum powder is placed in a feed bin and stirred and dispersed, then pressed into shape by an automatic hydraulic press, placed on a pad via a sponge suction cup and transported to a roller kiln, fired in a roller kiln at 1050°C for 6 hours, then crushed and ball-milled in an automatic continuous ball mill to obtain calcined talcum powder for high-whiteness building materials.

[0054] Comparative Example 3

[0055] (1) 1 kg of black talc was crushed into particles with a particle size of 100-200 mesh, then added into 5 L of 20% hydrochloric acid solution and pickled at 25 °C for 1 h.

[0056] (2) Filter the acid solution, wash with water, then disperse 1 kg of black talcum powder in 5 L of water, add 0.25 kg of sodium dithionite, and rinse at 35°C for 4 hours.

[0057] (3) After rinsing, filter and wash with water. Place 1 kg of the washed talc in a flotation machine, add 3 L of water, 3 g of auxiliary fatty alcohol ether phosphate MOA-3P, and 0.5 g of a frother (brand KF-F1), add sodium hydroxide to control the pH of the slurry to 10, and perform positive flotation. After flotation purification, dry and dehydrate the slurry.

[0058] (4) The dried and dehydrated talcum powder is placed in a feed bin and stirred and dispersed, then pressed into shape by an automatic hydraulic press, placed on a pad via a sponge suction cup and transported to a roller kiln, fired in a roller kiln at 1050°C for 6 hours, then crushed and ball-milled in an automatic continuous ball mill to obtain calcined talcum powder for high-whiteness building materials.

[0059] Comparative Example 4

[0060] (1) 1 kg of black talc was crushed into particles with a particle size of 100-200 mesh, then added into 5 L of 20% hydrochloric acid solution and pickled at 25 °C for 1 h.

[0061] (2) Filter the acid solution, wash with water, then disperse 1 kg of black talcum powder in 5 L of water, add 0.25 kg of sodium dithionite, and rinse at 35°C for 4 hours.

[0062] (3) After rinsing, filter and wash with water. Place 1 kg of the washed talc in a flotation machine, add 3 L of water, 2 g of collector fatty alcohol polyoxyethylene ether sulfonate FXS, and 0.5 g of frother (brand KF-F1), add sodium hydroxide to control the pH of the slurry to 10, and perform positive flotation. After flotation purification, dry and dehydrate the slurry.

[0063] (4) The dried and dehydrated talcum powder is placed in a feed bin and stirred and dispersed, then pressed into shape by an automatic hydraulic press, placed on a pad via a sponge suction cup and transported to a roller kiln, fired in a roller kiln at 1050°C for 6 hours, then crushed and ball-milled in an automatic continuous ball mill to obtain calcined talcum powder for high-whiteness building materials.

[0064] The whiteness of talcum powder was measured by a fully automatic whiteness meter. The talcum powder was analyzed by an XRD X-ray diffractometer to test the talc content in the talcum powder. The results are shown in Table 1.

[0065] Table 1 Talc whiteness and talc content determination

[0066] Whiteness (%) Talc content (%) Example 1 92.7 91.2 Example 2 95.2 86.4 Example 3 90.3 89.0 Example 4 94.5 93.5 Example 5 92.2 91.6 Comparative Example 1 82.6 91.7 Comparative Example 2 84.5 80.4 Comparative Example 3 90.9 62.3 Comparative Example 4 91.1 66.8

[0067] In Examples 1-5, the black talc ore powder was acid-washed, rinsed with sodium dithionite, and flotated and purified in a flotation system of fatty alcohol polyoxyethylene ether sulfonate, fatty alcohol ether phosphate MOA-3P, etc. to reduce impurity minerals in the talc ore and optimize the associated structure. Finally, after calcination, the whiteness of the obtained talc powder was 90.3-95.2%, and the talc content reached 86.4-93.5%.

[0068] The black talc powder of Comparative Example 1 was not rinsed with sodium dithionite, and the whiteness of the talc powder was only 82.6%. The black talc powder of Comparative Example 2 was not pickled with hydrochloric acid, and the whiteness of the talc powder was only 84.5%.

[0069] In the flotation system of Comparative Example 3, no fatty alcohol polyoxyethylene ether sulfonate FXS was added, and in Comparative Example 4, no fatty alcohol ether phosphate MOA-3P was added, and the talc contents were only 62.3% and 66.8% respectively.

[0070] With reference to GB / T 21114-2019 and GB / T 23774-2009 standards, the composition of the calcined talcum powder for high whiteness building materials in Example 1 was detected and analyzed.

[0071] Table 2 Composition detection of calcined talc

[0072] project content(%) IL (burn reduction) 0.44 <![CDATA[Al 2 THE 3 ]]> 0.48 <![CDATA[SiO 2 ]]> 66.22 <![CDATA[Fe 2 THE 3 ]]> 0.05 CaO 2.68 MgO 29.67 <![CDATA[K 2 The]]> 0.02 <![CDATA[Na 2 The]]> 0.16

[0073] It can be seen from Table 2 that the effective component SiO in calcined talc is 2 and MgO content is high, Al 2 O 3 The impurity content is less.

[0074] Although the embodiments of the present invention have been disclosed as above, they are not limited to the applications listed in the specification and the implementation modes. They can be fully applied to various fields suitable for the present invention. For those familiar with the art, additional modifications can be easily implemented. Therefore, without departing from the general concept defined by the claims and the scope of equivalents, the present invention is not limited to specific details.

Claims

1. A method for producing calcined talc powder for high whiteness building materials using black talc, characterized in that: Here are the steps: (1) crushing black talc ore into particles and adding them into acid solution for pickling; wherein the acid solution is a hydrochloric acid solution with a mass fraction of 15-20%; the particle size of the black talc after crushing into particles is 100-200 mesh; (2) filtering the acid solution, washing with water, then dispersing the black talc powder in water, and adding sodium dithionite for rinsing; wherein the mass of the sodium dithionite is 10-30% of the mass of the black talc powder; (3) After rinsing, filtering and washing with water, the washed talc is placed in a flotation machine, and water, a collector, an auxiliary agent, a frother and sodium hydroxide are added to prepare a mineral slurry, and positive flotation is performed. After flotation purification, the mineral slurry is dried and dehydrated; Wherein, the amount of the collector is 0.2-0.5% of the mass of talc powder, and the collector is fatty alcohol polyoxyethylene ether sulfonate FXS; The dosage of the auxiliary agent is 0.1-0.3% of the mass of talc powder, and the auxiliary agent is fatty alcohol ether phosphate MOA-3P; In (3), sodium hydroxide is added to adjust the pH of the flotation ore slurry to 10; (4) The dried and dehydrated talc powder is placed in a feed bin and stirred and dispersed, then pressed into shape by a hydraulic press, placed on a pad by a suction cup and transported to a roller kiln, fired in a roller kiln, and then crushed and ball-milled in a continuous ball mill to obtain calcined talc powder for high-whiteness building materials; the firing temperature is 1050-1190°C, and the firing time is 5-7h.