Application and application method of n-heptyl-selenium-n-octyl sulfate sodium as an anti-corrosion and plasticizer for ceramic blanks

Abstract

This invention provides the application and method of sodium n-heptyl-selenyl-n-octyl sulfate as an anti-corrosion and plasticizing agent for ceramic bodies, belonging to the field of ceramic raw material processing technology. The selenium ether group (-Se-) in the sodium n-heptyl-selenyl-n-octyl sulfate molecule possesses unique redox regulation and biological metabolic intervention capabilities. This invention directly addresses the core problems of surface mold growth and internal anaerobic putrefaction during the aging of ceramic bodies. By using sodium n-heptyl-selenyl-n-octyl sulfate as an anti-corrosion and plasticizing agent for ceramic bodies, it effectively inhibits the activity of harmful microorganisms and reduces the generation of organic acids, thereby maintaining good plasticity, bonding strength, and chemical stability of the body during long-term storage.

Description

Technical Field

[0001] This invention relates to the field of ceramic raw material processing technology, specifically to the application and application method of sodium n-heptyl-selenyl-n-octyl sulfate as an anti-corrosion and plasticizing agent for ceramic blanks. Background Technology

[0002] In ceramic production using plastic forming methods (such as rolling, extrusion, and throwing), the slurry obtained from ball milling needs to be dehydrated by pressure filtration to produce ceramic plastic blanks with a certain shape and moisture content, commonly known as "clay segments" or "clay material." These blanks typically need to be aged in a clay silo for several weeks or even months to homogenize moisture, reduce stress, and improve plasticity and forming performance. However, this long aging period is a high-risk stage for biological deterioration of the blanks, for example: ① Surface mold growth: In mud storage environments with high humidity, mold easily grows on the surface of the billets, forming various colored mold spots. This not only affects the appearance and hygiene of the billets, but also requires the surface layer to be removed during use, resulting in direct waste of raw materials and increased labor costs.

[0003] ② Internal anaerobic putrefaction: The plastic billet has poor internal permeability. During stacking and storage, external oxygen is rapidly consumed by surface microorganisms, quickly creating an anaerobic environment inside. Under these conditions, anaerobic microorganisms (such as Clostridium bacteria) become dominant, decomposing the organic matter in the billet (such as humic acid associated with clay and added organic binders) through fermentation and metabolism. Although this process does not produce obvious bubbles, it continuously generates and accumulates low-molecular-weight organic acids (such as butyric acid and acetic acid), leading to an irreversible decrease in the internal pH value of the billet and producing a characteristic rancid and putrid odor.

[0004] ③ Severe performance degradation: The aforementioned biochemical processes severely damage the colloidal structure of the billet. Macroscopically, this manifests as the billet not becoming "more mature and usable" after long-term aging, but instead exhibiting "brittleness" and "slag-like" phenomena. This significantly reduces the billet's plasticity and weakens its bonding strength. When using such billets for molding, insufficient ductility leads to easy cracking, low drying strength, and ultimately a decrease in yield.

[0005] Currently, the industry lacks targeted solutions and mainly relies on physical methods such as controlling environmental temperature and humidity and turning the clay, which have limited effectiveness and are costly. Developing a chemical additive that can inhibit the spoilage of billets at the source and maintain their processing properties has an urgent production need and significant economic value. Summary of the Invention

[0006] In view of this, the purpose of this invention is to provide the application and method of using sodium n-heptyl-selenyl-n-octyl sulfate as an anti-corrosion and plasticizing agent for ceramic blanks. This invention uses sodium n-heptyl-selenyl-n-octyl sulfate as an anti-corrosion and plasticizing agent for ceramic blanks, which can effectively inhibit the spoilage and deterioration of the blanks caused by microbial action and maintain their good plasticity.

[0007] To achieve the above-mentioned objectives, the present invention provides the following technical solution: This invention provides the application of sodium n-heptyl-selenyl-n-octyl sulfate as a corrosion inhibitor and plasticizer for ceramic blanks.

[0008] Preferably, the added mass of sodium n-heptyl-selenyl-n-octyl sulfate is 0.05~0.2% of the dry basis mass of the ceramic green body.

[0009] Preferably, the sodium n-heptyl-selenyl-n-octyl sulfate is added after the ball milling process of the ceramic blank and before the dehydration process.

[0010] This invention provides a method for preparing ceramic corrosion-resistant plastic blanks based on sodium n-heptyl-selenyl-n-octyl sulfate, comprising the following steps: The ceramic blank raw material, deflocculant and water are mixed and ball-milled to obtain ceramic slurry; The ceramic blank slurry is mixed with sodium n-heptyl-selenium-n-octyl sulfate and dehydrated to obtain a primary blank; The primary blank is subjected to vacuum refining and aging to obtain a ceramic corrosion-resistant plastic blank.

[0011] Preferably, the ceramic body raw materials, by mass percentage, comprise 40-50% clay, 25-35% quartz, and 20-30% feldspar; The clay includes one or more of kaolin, Xuyong clay, and pearl clay; the organic matter content of the clay is ≤1.5%; The mass ratio of the total amount of the ceramic raw material after batching to water is 1:0.5~1.2.

[0012] Preferably, the degumming agent includes one or more of water glass, sodium carboxymethyl cellulose, sodium tripolyphosphate, sodium humate, sodium carbonate, and sodium polyacrylate; The mass of the degumming agent is 0.1~0.8% of the dry basis mass of the ceramic blank.

[0013] Preferably, the mass of the sodium n-heptyl-selenyl-n-octyl sulfate is 0.05~0.2% of the dry basis mass of the ceramic green body.

[0014] Preferably, the ball milling speed is 20-40 rpm, the time is 16-22 h, and the fineness of the ceramic blank slurry after ball milling is 0.2-0.8 wt% residue on a 250 mesh sieve; The water content of the dewatered slurry is 19-26%.

[0015] Preferably, the vacuum degree of the vacuum slurry is -0.095 to -0.0987 MPa, the extrusion speed is 0.2 to 3.0 m / min, and the extrusion pressure is 3 to 4 MPa; The aging temperature is 15~40℃, the time is ≥5 days, and the humidity of the aging environment is ≥80%.

[0016] The present invention provides a ceramic corrosion-resistant plastic blank prepared by the above method.

[0017] This invention provides the application of sodium n-heptyl-selenyl-n-octyl sulfate as an anti-corrosion and plasticizing agent for ceramic blanks. This invention directly addresses the core problems of surface mold growth and internal anaerobic putrefaction during the aging process of ceramic blanks. By using sodium n-heptyl-selenyl-n-octyl sulfate as an anti-corrosion and plasticizing agent for ceramic blanks, it effectively inhibits the activity of harmful microorganisms and reduces the formation of organic acids, thereby maintaining good plasticity, bonding strength, and chemical stability of the blanks during long-term storage. The structural formula of sodium n-heptyl-selenyl-n-octyl sulfate is: C7H 15 -Se-(CH2)8-OSO3Na, with its selenium ether group (-Se-), endows it with unique redox regulation and biometabolic intervention capabilities, enabling it to inhibit surface mold and suppress internal anaerobic putrefaction. Specifically, sodium n-heptyl-selen-n-octyl sulfate distributed on the surface of ceramic blanks can interfere with the germination of mold spores and hyphal growth, effectively reducing the formation of surface mold spots. Sodium n-heptyl-selen-n-octyl sulfate dispersed inside the ceramic blanks can regulate the redox potential of the anaerobic microenvironment, specifically interfering with the metabolic pathways of anaerobic fermenting bacteria (such as Clostridium), thereby significantly reducing the generation and accumulation of organic acids such as butyric acid and acetic acid. By inhibiting internal acidification, it effectively protects the clay colloidal structure and interparticle lubrication hydration film that maintain the plasticity of the ceramic blanks, ensuring the subsequent processability of the ceramic blanks.

[0018] Compared with the prior art, the present invention has the following outstanding advantages: ① Precise and efficient: It directly targets the root cause of microbial decay that leads to the deterioration of ceramic blanks, especially the internal anaerobic acidification process. It has a significant effect on corrosion prevention and plastic preservation, and can fundamentally solve the industry's persistent problems of "brittleness, slag formation, and odor".

[0019] ② Stable performance: It can maintain the plasticity index and drying strength of ceramic blanks for a long time. After 15 days of accelerated aging, the performance of ceramic blanks treated with sodium n-heptyl-selenyl-n-octyl sulfate is almost unaffected.

[0020] ③ Simple process: It only requires adding a mixing step before the existing mud dewatering process, without changing the main production process, without requiring additional equipment, and is easy to integrate and promote.

[0021] ④ Wide compatibility: This anti-corrosion and plasticizing agent has good compatibility with various inorganic and organic degumming agents commonly used in the ceramic industry (such as CMC and water glass) and can be used in combination. Attached Figure Description

[0022] Figure 1 The process flow diagram is shown for preparing ceramic corrosion-resistant plastic preforms based on sodium n-heptyl-selenyl-n-octyl sulfate. Figure 2 Photograph of the 15-day aged sample for comparison example 1; Figure 3 Photograph of the sample from Example 1 after 15 days of aging; Figure 4 A bright-field micrograph of Comparative Example 1 sample after 15 days of aging. Figure 5 This is a bright-field micrograph of the sample from Example 1 after aging for 15 days. Detailed Implementation

[0023] This invention provides the application of sodium n-heptyl-selenyl-n-octyl sulfate as a corrosion inhibitor and plasticizer for ceramic blanks.

[0024] In this invention, the preferred addition mass of sodium n-heptyl-selenyl-n-octyl sulfate is 0.05-0.2% of the ceramic blank (dry basis), more preferably 0.1-0.15%. This dosage range has been experimentally verified to ensure significant anti-corrosion effect while maintaining economy, and without negatively impacting other properties of the slurry and blank.

[0025] In this invention, the sodium n-heptyl-selenyl-n-octyl sulfate is preferably added after the ball milling process of the ceramic blank slurry and before the dewatering process. The slurry treated with sodium n-heptyl-selenyl-n-octyl sulfate is then subjected to pressure filtration and kneading according to conventional processes to produce plastic blanks. The sodium n-heptyl-selenyl-n-octyl sulfate is ultimately firmly adsorbed onto the surface of the clay particles, thus continuing to play a role in subsequent aging.

[0026] The present invention does not have any special requirements on the source of the sodium n-heptyl-selen-n-octyl sulfate. Commercially available sodium n-heptyl-selen-n-octyl sulfate or self-prepared sodium n-heptyl-selenium sulfate can be used.

[0027] This invention provides a method for preparing ceramic corrosion-resistant plastic blanks based on sodium n-heptyl-selenyl-n-octyl sulfate, comprising the following steps: The ceramic blank raw material, deflocculant and water are mixed and ball-milled to obtain a slurry; The slurry was mixed with sodium n-heptyl-selenyl-n-octyl sulfate and dehydrated to obtain a primary billet. The dewatered slurry is subjected to vacuum refining and aging to obtain a ceramic anti-corrosion plastic blank.

[0028] This invention involves mixing ceramic raw materials, a deflocculant, and water, followed by ball milling to obtain a ceramic slurry. In this invention, the ceramic raw material formula, by mass percentage, is: clay 40-50%, preferably 45%; quartz 25-35%, preferably 30%; feldspar 20-30%, preferably 25%. In this invention, the mass ratio of the total amount of the ceramic raw materials to water is preferably 1:0.5-1.2, more preferably 1:1.

[0029] In this invention, the clay preferably includes one or more of kaolin, Xuyong clay, and pearl clay, and the D of the clay raw material is... 50 The particle size is ≤2μm; in this invention, the organic matter content in the clay raw material is preferably ≤1.5%, more preferably 0.1~1.4%, and even more preferably 0.2~1.2%.

[0030] In this invention, the degumming agent preferably includes one or more of water glass, sodium carboxymethyl cellulose (CMC), sodium tripolyphosphate, sodium humate, sodium carbonate, and sodium polyacrylate. The mass of the degumming agent is preferably 0.1-0.8% of the mass of the ceramic blank raw material, more preferably 0.2-0.7%, and even more preferably 0.3-0.6%.

[0031] This invention does not have special requirements for the mixing method; any mixing method well known to those skilled in the art can be used, such as stirring. During the mixing process, this invention preferably adds grinding balls used in subsequent ball milling. In this invention, the mass ratio of the total amount of the ceramic raw material after batching to the mass of the grinding balls is preferably 1:1.5~2.5, more preferably 1:2.

[0032] The present invention preferably uses a rolling ball mill for the ball milling. In the present invention, the ball milling speed is preferably 20-40 rpm, more preferably 30 rpm, and the milling time is preferably 16-22 h, more preferably 18-20 h; the fineness of the ceramic blank slurry after ball milling is preferably 0.2-0.8 wt% residue on a 250-mesh sieve, more preferably 0.4-0.6 wt%. After ball milling, the present invention preferably discharges the slurry, and the discharge process preferably involves passing the slurry through a coarse sieve (such as a 40-mesh sieve) to remove larger particles.

[0033] After obtaining the ceramic blank slurry, the present invention mixes the ceramic blank slurry with sodium n-heptyl-selenyl-n-octyl sulfate and dehydrates it to obtain a dehydrated slurry. In the present invention, the mass of the sodium n-heptyl-selenyl-n-octyl sulfate is preferably 0.05~0.2% of the total amount of ceramic blank raw materials after batching, more preferably 0.1~0.15%. The present invention preferably carries out the mixing in a slurry tank.

[0034] In this invention, the dehydration is preferably pressure filtration dehydration, and the moisture content of the primary billet after dehydration is preferably 19-26%, more preferably 20-25%, and even more preferably 22-24%.

[0035] After obtaining the primary blank, the present invention subjectes the primary blank to vacuum refining and aging to obtain a ceramic corrosion-resistant plastic blank. In the present invention, the vacuum degree of the vacuum refining is preferably -0.095 to -0.0987 MPa, more preferably -0.096 to -0.097 MPa; the extrusion speed is preferably 0.2 to 3.0 m / min, more preferably 0.5 to 2.5 m / min, and even more preferably 1 to 2 m / min; the extrusion pressure is preferably 3 to 4 MPa, more preferably 3.5 MPa.

[0036] In this invention, the aging temperature is preferably 15~40℃, more preferably 20~25℃, and the time is preferably ≥5 days, more preferably 10~20 days; the humidity of the aging environment is preferably ≥80%, more preferably 80~90%.

[0037] As a specific embodiment of the present invention, the preparation flow chart of the ceramic anti-corrosion plastic preform is as follows: Figure 1 As shown.

[0038] The present invention provides a ceramic corrosion-resistant plastic blank prepared by the above method.

[0039] The following examples illustrate the application and application method of sodium n-heptyl-selenyl-n-octyl sulfate as an anti-corrosion and plasticizing agent for ceramic blanks. However, these examples should not be construed as limiting the scope of protection of this invention.

[0040] Preparation Example Sodium n-heptyl-selenyl-n-octyl sulfate was prepared using the following method: Step 1: Synthesis of intermediate 1,2-diheptyldiselenic ether Under nitrogen protection, selenium powder (31.6 g, 0.40 mol) and a mixture of 400 mL ethanol and 100 mL water were added to a 1 L three-necked flask equipped with a stir bar and a condenser. The flask was then cooled to 0°C in an ice-water bath. Sodium borohydride (9.46 g, 0.25 mol) was slowly added in portions with vigorous stirring. The addition rate was controlled to prevent violent gas release. After the addition was complete, the ice bath was removed, and the mixture was heated to 70°C and refluxed for 2 hours until the selenium powder was completely dissolved, yielding a deep red sodium diselenide (Na₂Se₂) solution.

[0041] The reaction mixture was cooled to room temperature, and 1-bromoheptane (96.0 g, 0.53 mol) was added in a single batch with stirring. The mixture was heated to 60 °C and stirred for 12 h. After the reaction was complete, the mixture was cooled to room temperature, and most of the ethanol was removed by vacuum distillation. 500 mL of water and 300 mL of dichloromethane were added to the residue, and the mixture was transferred to a separatory funnel, shaken thoroughly, and separated. The aqueous phase was then extracted with dichloromethane (2 × 200 mL). All organic phases were combined, washed with saturated brine, and dried over anhydrous sodium sulfate. After filtration, the mixture was concentrated under reduced pressure to obtain the crude product.

[0042] The crude product was purified by silica gel column chromatography (300-400 mesh silica gel, eluent: petroleum ether / ethyl acetate = 20:1, v / v). The main fraction was collected and concentrated under reduced pressure to obtain a pale yellow oily liquid, which solidified into a pale yellow waxy solid upon cooling, namely 1,2-diheptyldiselenic ether.

[0043] Step 2: Synthesis of intermediate sodium 8-bromooctyl sulfate Under nitrogen protection, 50.0 g (0.224 mol) of 8-bromo-1-octanol and 200 mL (anhydrous N,N-dimethylformamide) were added to a dry 500 mL three-necked flask and stirred until dissolved. Sulfur trioxide-pyridine complex (35.7 g, 0.224 mol) was added in portions while cooling and stirring in an ice-water bath. After the addition was complete, the ice bath was removed, and the reaction mixture was stirred at room temperature for 4 h. The reaction was monitored for completeness by TLC (evolving solvent: dichloromethane / methanol = 8:1).

[0044] The reaction solution was slowly poured into 1 L of vigorously stirred ice water, resulting in the formation of a white precipitate. Subsequently, under ice-water bath cooling, a 5 M sodium hydroxide aqueous solution was slowly added dropwise to adjust the pH of the mixture to 9–10. The precipitate dissolved, yielding an aqueous solution. This aqueous solution was transferred to a separatory funnel and washed with dichloromethane (3 × 150 mL) to remove DMF and any possible byproducts. The aqueous phase was concentrated to dryness under reduced pressure at 40 °C using a rotary evaporator, yielding a white or off-white solid. This solid was recrystallized from anhydrous ethanol to obtain a white powdery sodium 8-bromooctyl sulfate.

[0045] Step 3: Synthesis of the target product, sodium n-heptyl-selen-n-octyl sulfate. Under nitrogen protection, 1,2-diheptyldiselenic ether obtained in step one and freshly distilled anhydrous tetrahydrofuran (400 mL) after reflux with calcium hydride were added to a dry 1 L three-necked flask and stirred to dissolve. A suspension of sodium borohydride (3.78 g, 0.10 mol) in 50 mL of anhydrous tetrahydrofuran was slowly added dropwise while cooling in an ice-water bath. After the addition was complete, the ice bath was removed, and stirring was continued at room temperature for 1 h to obtain an orange-red sodium selenohydride solution.

[0046] In another dry 500 mL flask, the sodium 8-bromooctyl sulfate obtained in step two was suspended in 200 mL of anhydrous tetrahydrofuran and sonicated to ensure thorough dispersion. This suspension was then slowly added dropwise to the sodium selenide solution using a constant-pressure dropping funnel over 30 min. After the addition was complete, the reaction mixture was heated to 50 °C and stirred at this temperature for 6 h. The reaction was monitored by TLC (evolving solvent: dichloromethane / methanol = 5:1) until the starting material spot disappeared.

[0047] After the reaction was complete, the reaction solution was cooled to room temperature and concentrated under reduced pressure to 1 / 3 of its original volume. The concentrate was slowly poured into 500 mL of ice-cold diethyl ether, and a large amount of white solid precipitated. The solution was filtered, and the solid was washed with cold diethyl ether (3 × 50 mL). The crude product was further purified by silica gel column chromatography (300-400 mesh silica gel, eluent gradient: dichloromethane → dichloromethane / methanol = 10:1 → 5:1). The fractions containing the target product were collected, combined, and concentrated under reduced pressure. The residue was recrystallized from the ethanol / diethyl ether mixture to give a white crystalline solid, namely sodium n-heptyl-selen-n-octyl sulfate.

[0048] Example 1 (1) Mix the ceramic blank raw material, deflocculant and water, and ball mill to obtain ceramic slurry; The ceramic material formula is as follows: 45wt% clay, 30wt% quartz, and 25wt% feldspar; the clay is kaolin, and the organic matter content in the clay is ≤1.5%. The mass ratio of the total amount of ceramic body raw materials (dry basis) to water is 1:1; the deflocculant is CMC, and the mass of the deflocculant is 0.3% of the total mass of the body (dry basis); The ball milling rate was 30 rpm, and the time was 16 hours.

[0049] (2) The ceramic slurry is mixed with sodium n-heptyl-selenyl-n-octyl sulfate and dehydrated to obtain a primary blank; The mass of sodium n-heptyl-selenyl-n-octyl sulfate is 0.05% of the total amount (dry basis) of the raw materials for ceramic body. The dewatering was performed by pressure filtration, and the moisture content of the primary raw material was 20%.

[0050] (3) The dewatered slurry is subjected to vacuum refining and aging to obtain a ceramic anti-corrosion plastic blank; The vacuum degree of the vacuum slurry is -0.095 to -0.0987 MPa, the extrusion speed is 1.5 m / min, and the extrusion pressure is 3.5 MPa. Accelerated aging experiments: The clay strips were cut into standard test blocks, and the test blocks were placed in a high temperature and high humidity environment of 40±2℃ and 90±5% for accelerated aging to simulate harsh long-term storage conditions. The aging period was set to 15 days.

[0051] Examples 2-3 The preparation processes of Examples 2 and 3 are basically the same as those of Example 1, except that the types and amounts of degumming agents and the amounts of preservatives and plasticizers are different. The specific differences are shown in Table 1.

[0052] Comparative Examples 1-5 The preparation processes of Comparative Examples 1 to 5 and Example 1 are basically the same, the difference lies in the type and amount of degumming agent and the type and amount of preservative and plasticizer. The specific differences are shown in Table 1.

[0053] Table 1. Types and amounts of additives used in the examples and comparative examples.

[0054] Performance testing The sensory odor, plasticity index, and green flexural strength of the ceramic anti-corrosion plastic blanks obtained in the examples and comparative examples were tested. The plasticity index was determined according to QB / T 1322-2010 "Method for Determination of Plasticity Index of Ceramic Clay", and the green flexural strength was determined according to GB / T 3810.4-2016 "Test Methods for Ceramic Tiles Part 4: Determination of Modulus of Rupture and Breaking Strength". The test results are shown in Table 2.

[0055] Table 2 Performance test results of ceramic corrosion-resistant plastic preforms

[0056] As can be seen from the data in Table 2: Both Comparative Example 1 and Comparative Example 2 billets exhibited a mild sour odor after 7 days of accelerated decay, and a severe sour odor after 15 days. Simultaneously, their plasticity and dry billet strength decreased sharply (significantly lower than their initial values), indicating severe decay and deterioration. A photograph of the Comparative Example 1 sample after 15 days of aging is shown below. Figure 2 As shown, bacterial spots can be clearly seen on the billet.

[0057] Comparative Example 3 used sorbic acid, a common antibacterial agent. No sour smell appeared after 15 days, indicating that it had a good antibacterial effect. However, its plasticity index and green strength were 1.8 and 0.9 MPa, respectively, which could not meet the production requirements.

[0058] In Comparative Example 4, the amount of sodium n-heptyl-selenyl-n-octyl sulfate was 0.02% (<0.05%), which did not achieve the antibacterial effect. Therefore, the billets aged for 7 days and 15 days showed mild and moderate sour odor, respectively. The plasticity index and green strength were both low, which could not meet the production requirements.

[0059] In Comparative Example 5, due to the use of sodium n-heptyl-selenyl-n-octyl sulfate at 0.3% (>0.2%), the billet did not show any acidic odor or deterioration after aging for 15 days, but the plasticity index was low. Excessive surfactant caused a large amount of foaming, resulting in low green strength, which also failed to meet production requirements.

[0060] Example 1: Photograph of a sample aged for 15 days (as shown) Figure 3 As shown, the resulting billet surface is smooth and clean, without any bacterial spots. Even under accelerated conditions up to 40°C, all billets in the example groups did not develop a sour odor by day 15, and their plasticity and dry billet strength were well maintained, with performance data essentially unchanged from the initial state (day 3 data). This fully demonstrates that the corrosion-preserving and plasticizing agent of this invention has excellent corrosion-preserving effects and performance retention capabilities. It can be shown that sodium n-heptyl-selenyl-n-octyl sulfate exhibits significant corrosion-preserving and plasticizing effects within the experimental addition range (0.05~0.2%).

[0061] Figure 4 This is a bright-field micrograph of the Comparative Example 1 sample after 15 days of aging. Numerous uniform rod-shaped / short rod-shaped microorganisms, ranging in size from 0.5 to 2 μm, are clearly visible, consistent with typical bacterial morphology. These bacteria are clustered and attached to the surface and interstices of clay particles. The agglomeration of clay particles due to EPS (excessive osmotic pressure) indicates severe spoilage of the Comparative Example sample.

[0062] Figure 5 This is a bright-field micrograph of the sample from Example 1 after aging for 15 days. The observations show that no microorganisms matching bacterial characteristics (0.5~2μm, rod-shaped / short rod-shaped) were detected in the sample. It retained the original loose granular structure of clay, with clear interparticle spaces and no obvious aggregation, perfectly consistent with the intrinsic structure of clay unaffected by microorganisms. Typical birefringence (colored reflection) characteristics of clay minerals were visible in the field of view, and no flocculent structure caused by extracellular polymeric substances (EPS) secreted by microorganisms was found. The loose arrangement of clay particles, the absence of obvious bacterial and biofilm structures, and the presence of only a small amount of inherent clay impurities further demonstrate that the clay matrix itself is free of target bacteria and a large number of native microorganisms, indicating that the sample from Example 1 possesses excellent antibacterial properties.

[0063] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the principle of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. Application of sodium n-heptyl-selen-n-octyl sulfate as a corrosion inhibitor and plasticizer for ceramic blanks.

2. The application according to claim 1, characterized in that, The added mass of sodium n-heptyl-selenyl-n-octyl sulfate is 0.05~0.2% of the dry basis mass of the ceramic green body.

3. The application according to claim 1 or 2, characterized in that, The sodium n-heptyl-selenyl-n-octyl sulfate is added after the ball milling process of ceramic blanks and before the dehydration process.

4. A method for preparing ceramic corrosion-resistant plastic blanks based on sodium n-heptyl-selenyl-n-octyl sulfate, characterized in that, Includes the following steps: The ceramic blank raw material, deflocculant and water are mixed and ball-milled to obtain ceramic slurry; The ceramic slurry is mixed with sodium n-heptyl-selenyl-n-octyl sulfate and dehydrated to obtain a primary blank. The primary billet is subjected to vacuum smelting and aging to obtain a corrosion-resistant plastic billet.

5. The method according to claim 4, characterized in that, The ceramic body composition, by weight percentage, is: 40-50% clay, 25-35% quartz, and 20-30% feldspar; The clay includes one or more of kaolin, Xuyong clay, and pearl clay; the organic matter content of the clay is ≤1.5%; The mass ratio of the total amount of the ceramic raw material after batching to water is 1:0.5~1.

2.

6. The method according to claim 4, characterized in that, The degumming agent includes one or more of water glass, sodium carboxymethyl cellulose, sodium tripolyphosphate, sodium humate, sodium carbonate, and sodium polyacrylate. The mass of the degumming agent is 0.1~0.8% of the dry basis mass of the ceramic blank.

7. The method according to claim 4 or 6, characterized in that, The mass of the sodium n-heptyl-selenyl-n-octyl sulfate is 0.05~0.2% of the dry basis mass of the ceramic green body.

8. The method according to claim 4, characterized in that, The ball mill operates at a speed of 20-40 rpm for 16-22 hours, and the fineness of the ceramic blank slurry after ball milling is 0.2-0.8 wt% residue on a 250-mesh sieve. The water content of the dewatered slurry is 19-26%.

9. The method according to claim 4, characterized in that, The vacuum degree of the vacuum slurry is -0.095 to -0.0987 MPa, the extrusion speed is 0.2 to 3.0 m / min, and the extrusion pressure is 3 to 4 MPa. The aging temperature is 15~40℃, the time is ≥5 days, and the humidity of the aging environment is ≥80%.

10. The ceramic corrosion-resistant plastic blank prepared by the method according to any one of claims 4 to 9.

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