Heat-resistant ceramic healthy casserole and preparation method thereof

Abstract

The invention discloses a heat-resistant ceramic healthy casserole and a preparation method thereof, and belongs to the field of ceramic casserole and its manufacturing technology. The heat-resistant ceramic healthy casserole of the present invention includes the following formula raw materials by weight: blank: 16-22 parts of quartz, 20-30 parts of pottery clay, 12-22 parts of kaolin, 5-7 parts of calcite powder, 4-8 parts of plant ash; glaze layer: 20-25 parts of quartz, 10-14 parts of medical stone, 11-15 parts of purple wood festival soil, 6-10 parts of petalite, 8-12 parts of wollastonite powder, 0.6-1.8 parts of thorium dioxide, and 2.4-4.0 parts of barium zirconate. On the basis of traditional lithium porcelain casserole, the present invention selects petalite and wollastonite powder to cooperate with thorium dioxide instead of spodumene, and the formed quartz-medical stone-purple wood festival soil system can greatly reduce the thermal expansion coefficient of the casserole at high temperature, thereby significantly improving the temperature difference resistance of the casserole. The heat-resistant ceramic healthy casserole of the present invention has similar heat resistance and temperature difference resistance performance as the existing lithium porcelain casserole, and the lead and cadmium dissolution amount can still be kept at a low level at high temperature, which meets the current people's requirements for heat resistance and health of casseroles.

Description

Technical Field

[0001] The invention belongs to the technical field of ceramic casserole and its production, and particularly relates to a heat-resistant ceramic healthy casserole and a preparation method thereof. Background Art

[0002] Traditional clay pots are a type of pottery. The invention of pottery is a landmark in the history of human social development. As early as the Neolithic period, humans began to use sand-tempered pottery. After successive improvements, sand-tempered pottery has evolved into the clay pots we use today. Traditional clay pots are ceramic products made from quartz, feldspar, clay and other materials that are not easy to conduct heat. After high-temperature firing, they have the characteristics of air permeability, adsorption, uniform heat transfer, and slow heat dissipation. Due to the production process and raw material problems, traditional clay pots are not resistant to temperature differences and are prone to cracking. After long-term research and development and improvement, people added spodumene to the raw materials to produce high-temperature resistant lithium porcelain clay pots, which significantly improved the practicality of clay pots.

[0003] Nowadays, high-temperature resistant lithium porcelain casseroles have been put into daily production and life; however, with the rapid development of lithium batteries, spodumene mines have begun to be increasingly used in the production of lithium carbonate and then in the field of lithium-ion batteries, resulting in an increasing shortage of spodumene mines; at the same time, spodumene needs to be pre-treated by high-temperature calcination before firing casseroles, and spodumene accounts for a relatively high proportion of the raw materials used in the production of high-temperature resistant lithium porcelain casseroles, which has led to the high production cost of high-temperature resistant lithium porcelain casseroles. On the other hand, the glaze layer of traditional casseroles also contains some harmful elements. Experiments have shown that although the spodumene added to the glaze layer of lithium porcelain casseroles significantly improves the high-temperature resistance of casseroles, when the lithium porcelain casseroles are heated and cooked at high temperatures, the dissolution rate of harmful elements contained in the clay material in the glaze layer will be significantly accelerated. Although the temperature for household cooking is not high under normal circumstances, it may still be harmful to human health within the applicable high temperature range of lithium porcelain casseroles.

[0004] Based on this, in order to reduce the hazards of lithium porcelain casserole during use, improve its performance and effectively control production costs, the raw material formula of high temperature resistant lithium porcelain casserole still needs to be further optimized and improved. Summary of the invention

[0005] The present invention aims at the problem that harmful elements will be dissolved out during the use of the glaze layer of the casserole, causing harm, and the high cost of using spodumene to make a casserole with good temperature difference resistance, and provides a heat-resistant ceramic healthy casserole and a preparation method thereof. On the basis of the traditional lithium porcelain casserole, the present invention selects petalite and wollastonite powder in combination with thorium dioxide to replace spodumene, and the formed quartz-medical stone-purple wood sintering soil system can greatly reduce the thermal expansion coefficient of the casserole at high temperature, thereby significantly improving the temperature difference resistance of the casserole. In addition, the heat-resistant casserole prepared by the present invention can also effectively inhibit the dissolution of harmful elements such as lead and cadmium, thereby ensuring safety in use.

[0006] In order to achieve the above object, the present invention specifically adopts the following technical solutions:

[0007] The present invention provides a heat-resistant ceramic healthy casserole, which comprises the following formula raw materials by weight:

[0008] Green body: 16-22 parts of quartz, 20-30 parts of clay, 12-22 parts of kaolin, 5-7 parts of calcite powder, 4-8 parts of plant ash;

[0009] Glaze layer: 20-25 parts of quartz, 10-14 parts of medical stone, 11-15 parts of purple wood soil, 6-10 parts of petalite, 8-12 parts of wollastonite powder, 0.6-1.8 parts of thorium dioxide, and 2.4-4.0 parts of barium zirconate.

[0010] Preferably, the heat-resistant ceramic healthy casserole comprises the following ingredients by weight:

[0011] Body: 20 parts of quartz, 26 parts of clay, 15 parts of kaolin, 6 parts of calcite powder, 5 parts of plant ash;

[0012] Glaze layer: 24 parts of quartz, 13 parts of medical stone, 12 parts of purple wood soil, 7 parts of petalite, 10 parts of wollastonite powder, 1.2 parts of thorium dioxide, and 3.0 parts of barium zirconate.

[0013] On the basis of the traditional lithium porcelain casserole, the present invention selects petalite and wollastonite powder in combination with thorium dioxide to replace spodumene, the raw material cost is not high, the amount is greatly reduced, and no pretreatment is required, which has obvious advantages over the traditional spodumene. In addition, in the quartz-medical stone-purple wood-soil system formed by the present invention, when the temperature rises sharply, the above three can coordinate with each other to promote the continuous dissolution of quartz, on the one hand, inhibit the transformation of quartz to cristobalite, and on the other hand, promote the transformation of β-quartz to α-quartz, both of which can effectively reduce the thermal expansion coefficient of the glaze layer, balance the difference between the body and the glaze layer, and give the casserole excellent temperature difference resistance.

[0014] In view of the problem of heavy metal precipitation from the glaze layer, some casseroles adopt the unglazed process. Although the unglazed casseroles do not need to consider the problem of excessive heavy metal elements, the casseroles without the glaze layer are not only more prone to cracking, but also food residues are easy to enter the gaps during cooking, affecting normal use. On the whole, the advantages of glazed casseroles are more obvious. In view of the defect that harmful elements such as lead and cadmium in the glaze layer are accelerated to precipitate during high-temperature use, the present invention adds plant ash to the blank and barium zirconate to the glaze layer. In the quartz-medical stone-purple wood-soil system of the present invention, the combination of plant ash and barium zirconate can produce a certain internal adsorption effect on lead and cadmium, thereby effectively hindering their dissolution, thereby ensuring the safety of the casserole under high temperature conditions.

[0015] Medical stone is mainly semi-weathered medium-acidic granite, which is sweet, warm, non-toxic, and contains a variety of minerals required by the human body. The present invention introduces it into the glaze layer, and also additionally improves the health care function of the casserole.

[0016] Preferably, the thickness of the heat-resistant ceramic healthy casserole pot is controlled to be 0.60-0.72 cm.

[0017] The present invention also provides a method for preparing the above heat-resistant ceramic healthy casserole, comprising the following steps:

[0018] S1. Weigh the raw materials for preparing the casserole body and the glaze layer according to the formula ratio and set aside;

[0019] S2, taking each raw material for preparing the green body, adding water and grinding it into mud, and then subjecting the mud to screening, iron removal, filter pressing, mud kneading, and aging treatment to obtain a green body mixture for standby use;

[0020] S3, taking the raw materials for the glaze layer, adding water and grinding them into glaze slurry, and then sieving and removing iron from the glaze slurry to obtain a glaze mixture for standby use;

[0021] S4, pressing the blank mixture obtained in S2 into a shape, drying, and trimming the blank to obtain a primary blank;

[0022] S5, bisque-firing the primary blank obtained in S4, and then glazing it with the glaze mixture obtained in S3 to obtain a bisque-fied blank, and transferring the bisque-fied blank to a high-temperature environment for glaze-firing to obtain a finished casserole.

[0023] Preferably, the mass ratio of S2 green body raw material to water is 1:1, the grinding and screening conditions are that the residue on 270 mesh sieve does not exceed 1%, and the product is sieved through 250 mesh sieve out of the mill, followed by iron removal, filter pressing, mud kneading, and aging; the moisture content of the resulting green body mixture is controlled to be 18%-22%.

[0024] Preferably, the mass ratio of S3 glaze layer raw material to water is 1:1.2, the grinding and screening conditions are that the residue on 325 mesh sieve does not exceed 1%, the mill is sieved through 250 mesh sieve, and then iron is removed; the concentration of the obtained glaze mixture is controlled to be 52-55 degrees Baume.

[0025] Preferably, the specific operation of S5 biscuit firing is: biscuit firing the primary blank at 1150°C for 7-10 hours, keeping the temperature for 1 hour, cooling it in the furnace and then glazing it.

[0026] Preferably, the specific operation of S5 glaze firing is: firing the glazed unglazed body at 1240°C for 3-4.5h, then heating to 1300°C for 4-6h, keeping the temperature for 1h and then cooling with the furnace to obtain the finished casserole.

[0027] Preferably, the thickness of S5 glazing is 0.3-0.5 mm.

[0028] Compared with the prior art, the present invention has the following beneficial effects:

[0029] 1. Based on the traditional lithium porcelain casserole, the present invention uses petalite and wollastonite powder in combination with thorium dioxide to replace spodumene. The raw material cost is not high, the dosage is greatly reduced, and no pretreatment is required. Compared with traditional spodumene, it has obvious advantages.

[0030] 2. The heat-resistant ceramic healthy casserole prepared by the present invention has excellent heat resistance and temperature difference resistance, which is similar to the performance of the existing lithium porcelain casserole, and can be well replaced by the lithium porcelain casserole in life.

[0031] 3. The heat-resistant ceramic healthy casserole prepared by the present invention is also easy to clean, safe and healthy. The amount of lead and cadmium dissolved is significantly reduced compared with conventional glazed casseroles, and the amount of lead and cadmium dissolved can still be maintained at a low level at high temperatures, which meets people's current requirements for heat resistance and health of casseroles. DETAILED DESCRIPTION

[0032] In order to make the purpose, technical scheme and advantages of the present invention clearer, the technical scheme of the present invention will be clearly and completely described below in conjunction with the embodiments. If the specific conditions are not specified in the embodiments, they are carried out according to the conventional conditions or the conditions recommended by the manufacturer. If the manufacturer of the reagents or instruments is not specified, they are all conventional products that can be purchased commercially.

[0033] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art of the present invention. The terms used in the specification of the present invention are only for the purpose of describing specific embodiments and are not intended to limit the present invention. The term "and / or" used herein includes any and all combinations of one or more related listed items.

[0034] The raw materials of the casserole involved in the experiment of the present invention are all commercially available, among which the purity of quartz is 96.93%; the main components of pottery clay are SiO2 70.03%, Al2O3 15.89%, Fe2O3 4.75%, CaO 1.23%, and MgO 1.83%; the main components of kaolin are SiO2 49.12%, Al2O3 36.44%, and H2O 13.08%; the main components of medical stone are SiO2 66.32%, Al2O317.05%, Fe2O3 2.30%, CaO 3.16%, Na2O 1.1%, K2O 1.2%, TiO2 0.63%, and MnO 0.75%; the main components of purple wood soil are SiO2 38.37%, Al2O3 37.88%, Fe2O31.81%, TiO2 1.70%, P2O5 0.17%, ZrO2 0.09%; the main components of petalite are Li2O 4.33%, Al2O3 17.04%, SiO2 74.39%, Na2O 0.68%, Cs2O 0.12%, CaO 0.19%.

[0035] Example 1

[0036] A method for preparing a heat-resistant ceramic healthy casserole, comprising:

[0037] 1. Weigh 20 parts of quartz, 26 parts of clay, 15 parts of kaolin, 6 parts of calcite powder and 5 parts of wood ash by weight, mix them, add deionized water of equal weight to the mixture, grind to a particle size of no more than 1% on a 270-mesh sieve, pass through a 250-mesh sieve, then remove iron, filter, knead mud and age in sequence to obtain a green mixture with a moisture content of 20.5% for use.

[0038] 2. Weigh 24 parts of quartz, 13 parts of medical stone, 12 parts of purple wood soil, 7 parts of petalite, 10 parts of wollastonite powder, 1.2 parts of thorium dioxide, and 3.0 parts of barium zirconate by weight, mix them, add 1.2 times the mass of deionized water of the mixture, grind to a particle size of no more than 1% on a 325-mesh sieve, pass through a 250-mesh sieve, then remove iron, and control the concentration of the glaze mixture to be 54 degrees Baume.

[0039] 3. Press the obtained blank mixture into shape, dry and trim the blank to obtain a primary blank; take the primary blank and bisque-fire it at 1150°C for 8.5 hours, keep it warm for 1 hour and then cool it with the furnace, then glaze it with the obtained glaze mixture (thickness 0.4mm) to obtain a bisque-fired blank, fire the bisque-fired blank at 1240°C for 4 hours, then raise the temperature to 1300°C and fire it for 5 hours, keep it warm for 1 hour and then cool it with the furnace to obtain a finished casserole.

[0040] Example 2

[0041] A method for preparing a heat-resistant ceramic healthy casserole, comprising:

[0042] 1. Weigh 16 parts of quartz, 30 parts of clay, 12 parts of kaolin, 6 parts of calcite powder and 4 parts of wood ash by weight, mix them, add deionized water of equal weight to the mixture, grind to a particle size of no more than 1% on a 270-mesh sieve, pass through a 250-mesh sieve, then remove iron, filter, knead mud and age in sequence to obtain a green mixture with a moisture content of 18% for use.

[0043] 2. Weigh 25 parts of quartz, 10 parts of medical stone, 11 parts of purple wood soil, 10 parts of petalite, 8 parts of wollastonite powder, 0.6 parts of thorium dioxide, and 4.0 parts of barium zirconate by weight, mix them, add 1.2 times the mass of deionized water of the mixture, grind to a particle size of no more than 1% on a 325-mesh sieve, pass through a 250-mesh sieve, then remove iron, and control the concentration of the glaze mixture to be 52 degrees Baume.

[0044] 3. Press the obtained blank mixture into shape, dry and trim the blank to obtain a primary blank; take the primary blank and bisque-fire it at 1150°C for 7 hours, keep it warm for 1 hour and then cool it with the furnace, then glaze it with the obtained glaze mixture (thickness 0.5mm) to obtain a bisque-fired blank, fire the bisque-fired blank at 1240°C for 4.5 hours, then raise the temperature to 1300°C and fire it for 4 hours, keep it warm for 1 hour and then cool it with the furnace to obtain a finished casserole.

[0045] Example 3

[0046] A method for preparing a heat-resistant ceramic healthy casserole, comprising:

[0047] 1. Weigh 22 parts of quartz, 20 parts of clay, 22 parts of kaolin, 6 parts of calcite powder and 8 parts of wood ash by weight, mix them, add deionized water of equal weight to the mixture, grind to a particle size of no more than 1% on a 270-mesh sieve, pass through a 250-mesh sieve, then remove iron, filter, knead mud and age in sequence to obtain a green mixture with a moisture content of 22% for use.

[0048] 2. Weigh 20 parts of quartz, 14 parts of medical stone, 15 parts of purple wood soil, 6 parts of petalite, 12 parts of wollastonite powder, 1.8 parts of thorium dioxide, and 2.4 parts of barium zirconate by weight, mix them, add 1.2 times the mass of deionized water of the mixture, grind to a particle size of no more than 1% on a 325-mesh sieve, pass through a 250-mesh sieve, then remove iron, and control the concentration of the glaze mixture to be 55 degrees Baume.

[0049] 3. Press the obtained blank mixture into shape, dry and trim the blank to obtain a primary blank; take the primary blank and bisque-fire it at 1150°C for 10 hours, keep it warm for 1 hour and then cool it with the furnace, then glaze it with the obtained glaze mixture (thickness 0.3mm) to obtain a bisque-fired blank, fire the bisque-fired blank at 1240°C for 3 hours, then raise the temperature to 1300°C and fire it for 6 hours, keep it warm for 1 hour and then cool it with the furnace to obtain a finished casserole.

[0050] Comparative Example 1

[0051] A method for preparing a casserole, which is different from that of Example 1 in that no plant ash is added to the raw materials for preparing the blank in step 1. That is, 20 parts of quartz, 26 parts of clay, 15 parts of kaolin, and 6 parts of calcite powder are weighed by weight, mixed, ground with water, sieved, iron removed, filtered, kneaded, and aged to prepare a blank mixture.

[0052] Comparative Example 2

[0053] A method for preparing a casserole, which is different from Example 1 in that spodumene is used in step 2 to replace petalite, wollastonite powder, and thorium dioxide in the raw materials for preparing the glaze. That is, 24 parts of quartz, 13 parts of medical stone, 12 parts of purple wood soil, 18.2 parts of spodumene, and 3.0 parts of barium zirconate are weighed by weight, mixed, ground with water, sieved, and iron removed to prepare a glaze mixture.

[0054] Comparative Example 3

[0055] A method for preparing a casserole, which is different from that of Example 1 in that barium zirconate is not added to the raw materials for preparing the glaze in step 2. That is, 24 parts of quartz, 13 parts of medical stone, 12 parts of purple wood knotweed, 7 parts of petalite, 10 parts of wollastonite powder, and 1.2 parts of thorium dioxide are weighed by weight, mixed, ground with water, sieved, and iron removed to prepare a glaze mixture.

[0056] Comparative Example 4

[0057] A method for preparing a casserole, which is different from that of Example 1 in that no purple wood soil is added to the raw materials for preparing the glaze in step 2. That is, 24 parts of quartz, 13 parts of medical stone, 7 parts of petalite, 10 parts of wollastonite powder, 1.2 parts of thorium dioxide, and 3.0 parts of barium zirconate are weighed by weight, mixed, ground with water, sieved, and iron removed to prepare a glaze mixture.

[0058] Test example

[0059] According to the relevant standards of GB 4806.4-2016 and GB / T 3298-2022, the casserole samples prepared in the above Examples 1-3 and Comparative Examples 1-4 were tested for lead and cadmium dissolution, temperature difference resistance and other performances; the results are shown in Table 1.

[0060] Table 1

[0061]

[0062] According to the lead-cadmium dissolution and temperature difference resistance test results in the above table, the heat-resistant ceramic healthy casserole prepared by using petalite and wollastonite powder in combination with thorium dioxide instead of spodumene can achieve the same high heat resistance and high temperature difference resistance as the existing lithium porcelain casserole prepared by using higher-cost spodumene, and effectively reduce the production cost while overcoming the insufficient high temperature resistance of the casserole. In addition, the lead-cadmium dissolution amount of the heat-resistant ceramic healthy casserole prepared by the present invention is not much different under high and low temperature environmental conditions, so it can be inferred that the heat-resistant ceramic healthy casserole of the present invention can still maintain a low level of lead-cadmium dissolution under high temperature cooking conditions, which is safe and harmless to the human body. However, according to the change in lead-cadmium dissolution under high and low temperature environmental conditions of the lithium porcelain casserole, its safety and stability under high temperature cooking conditions cannot be guaranteed.

[0063] The embodiments described above only express several preferred embodiments of the present invention, and the descriptions thereof are relatively specific and detailed, but are not intended to limit the present invention. It should be noted that for those skilled in the art, the present invention may also have various changes and modifications, and any modifications, equivalent substitutions, improvements, etc. made within the concept and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A heat-resistant ceramic healthy casserole, characterized in that: The formula includes the following raw materials by weight: Green body: 16-22 parts of quartz, 20-30 parts of clay, 12-22 parts of kaolin, 5-7 parts of calcite powder, 4-8 parts of plant ash; Glaze layer: 20-25 parts of quartz, 10-14 parts of medical stone, 11-15 parts of purple wood soil, 6-10 parts of petalite, 8-12 parts of wollastonite powder, 0.6-1.8 parts of thorium dioxide, and 2.4-4.0 parts of barium zirconate.

2. The heat-resistant ceramic healthy casserole according to claim 1, characterized in that: The formula includes the following raw materials by weight: Body: 20 parts of quartz, 26 parts of clay, 15 parts of kaolin, 6 parts of calcite powder, 5 parts of plant ash; Glaze layer: 24 parts of quartz, 13 parts of medical stone, 12 parts of purple wood soil, 7 parts of petalite, 10 parts of wollastonite powder, 1.2 parts of thorium dioxide, and 3.0 parts of barium zirconate.

3. The heat-resistant ceramic healthy casserole according to claim 1, characterized in that: The thickness of the heat-resistant ceramic healthy casserole pot is controlled to be 0.60-0.72 cm.

4. The method for preparing the heat-resistant ceramic healthy casserole according to any one of claims 1 to 3, characterized in that: The steps include: S1. Weigh the raw materials for preparing the casserole body and the glaze layer according to the formula ratio and set aside; S2, taking each raw material for preparing the green body, adding water and grinding it into mud, and then subjecting the mud to screening, iron removal, filter pressing, mud kneading, and aging treatment to obtain a green body mixture for standby use; S3, taking the raw materials for the glaze layer, adding water and grinding them into glaze slurry, and then sieving and removing iron from the glaze slurry to obtain a glaze mixture for standby use; S4, pressing the blank mixture obtained in S2 into a shape, drying, and trimming the blank to obtain a primary blank; S5, bisque-firing the primary blank obtained in S4, and then glazing it with the glaze mixture obtained in S3 to obtain a bisque-fied blank, and transferring the bisque-fied blank to a high-temperature environment for glaze-firing to obtain a finished casserole.

5. The method for preparing the heat-resistant ceramic healthy casserole according to claim 4, characterized in that: The mass ratio of S2 green body raw material to water is 1:1, the grinding and screening conditions are that the residue on 270 mesh sieve does not exceed 1%, and the product is sieved through 250 mesh sieve, followed by iron removal, filter pressing, mud kneading and aging; the moisture content of the obtained green body mixture is controlled to be 18%-22%.

6. The method for preparing the heat-resistant ceramic healthy casserole according to claim 4, characterized in that: S3 glaze raw materials are added with water, wherein the mass ratio of the glaze raw materials to water is 1:1.2, the grinding and screening conditions are that the residue on a 325-mesh sieve does not exceed 1%, the material is sieved through a 250-mesh sieve out of the mill, and then iron is removed; the concentration of the resulting glaze mixture is controlled to be 52-55 degrees Baume.

7. The method for preparing the heat-resistant ceramic healthy casserole according to claim 4, characterized in that: The specific operation of S5 biscuit firing is: biscuit the primary blank at 1150℃ for 7-10 hours, keep it warm for 1 hour, cool it in the furnace and then glaze it.

8. The method for preparing the heat-resistant ceramic healthy casserole according to claim 4, characterized in that: The specific operation of S5 glaze firing is as follows: the glazed unglazed body is fired at 1240°C for 3-4.5 h, then heated to 1300°C and fired for 4-6 h, kept at this temperature for 1 h, and then cooled with the furnace to obtain the finished casserole.

9. The method for preparing the heat-resistant ceramic healthy casserole according to claim 4, characterized in that: The thickness of S5 glazing is 0.3-0.5 mm.

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