Preparation method of high silver / zinc loading zirconium phosphate antibacterial agent

Abstract

This invention discloses a method for preparing a high-silver / zinc-loaded zirconium phosphate antibacterial agent. The method involves the preparation of a zirconium phosphate carrier, the preparation of intercalated zirconium phosphate, ion exchange, and calcination to obtain the high-silver / zinc-loaded zirconium phosphate antibacterial agent. This invention features a simple process, short reaction time, controllable loading, and high raw material utilization, effectively overcoming the shortcomings of existing technologies such as low loading, long reaction time, uncontrollable loading, and high process cost, thus better meeting application requirements.

Description

Technical Field

[0001] This invention relates to the field of antibacterial materials technology, and in particular to a method for preparing a high silver / zinc loaded zirconium phosphate antibacterial agent. Background Technology

[0002] Antibacterial materials are mainly divided into three categories: natural antibacterial agents, organic antibacterial agents, and inorganic antibacterial agents. Natural antibacterial agents are extracted and refined from plants and animals, possessing advantages such as good antibacterial effects and minimal harm to the environment and human body. However, their heat resistance is poor, generally starting to carbonize and decompose at 150-180℃, limiting their application range. Organic antibacterial agents mainly include acylanilines, imidazoles, thiazoles, isothiazolone derivatives, bisulfones, and phenols, possessing strong bactericidal capabilities. However, they have disadvantages such as poor safety, the development of microbial resistance, poor chemical stability, and short lifespan of antibacterial products. Their heat resistance is also poor, easily decomposing and inactivating under high temperature and pressure, and their decomposition products can even be toxic. Inorganic antibacterial agents have advantages such as long-lasting antibacterial activity, broad spectrum, good heat resistance, high safety, and no development of drug resistance. Therefore, inorganic antibacterial agents are widely used in building materials, medical devices, and textiles. Metallic antibacterial agents are an important component of inorganic antibacterial agents. Among numerous antibacterial metal ions, silver ions possess far superior antibacterial capabilities compared to other metal ions, thus leading to the increasingly widespread application of silver-based inorganic antibacterial agents. Currently, the most researched and applied silver-based antibacterial materials both domestically and internationally fall into two main categories: nano-silver antibacterial materials and silver-loaded antibacterial materials.

[0003] Silver-loaded antibacterial materials mainly achieve their antibacterial effect by attaching silver ions to the surface or mesopores of inorganic materials through ion exchange and physical adsorption. Common carriers include zeolite, montmorillonite, soluble glass, layered zirconium phosphate, hydroxyapatite, and phosphates.

[0004] Zirconium phosphate, also known as zirconium hydrogen phosphate, is a layered compound insoluble in water and organic solvents. It is resistant to strong acids and certain alkalis, possesses a large specific surface area and surface charge, and is a strong solid acid with excellent ion exchange properties. Therefore, zirconium phosphate is commonly used as a carrier for inorganic antibacterial agents. The conventional method for exchanging zirconium phosphate with metal cations involves placing it in an aqueous solution of metal ions and loading the metal ions onto the zirconium phosphate by controlling the reaction time and metal ion concentration. Currently, this method requires an excess of inorganic metal salt or a long ion exchange reaction time to load silver ions onto the zirconium phosphate. However, the loading of silver ions is uncontrollable, and a large amount of silver ions remain in the solution. Since silver is a precious metal, its cost is high, and the silver ions in the solution need to be recovered, increasing the process difficulty and production cost significantly. In summary, existing methods for preparing silver-loaded zirconium phosphate antibacterial agents have drawbacks such as long exchange time, incomplete ion exchange, uncontrollable silver loading, low silver loading, and high process costs, thus failing to meet the requirements. Summary of the Invention

[0005] The purpose of this invention is to overcome the shortcomings of the prior art and provide a method for preparing a high silver / zinc loaded zirconium phosphate antibacterial agent with simple process, short reaction time, and controllable loading, so as to solve the disadvantages of low loading, long reaction time, uncontrollable loading, and high process cost of the prior art, thereby better meeting the needs of use.

[0006] The objective of this invention is achieved through the following technical solution:

[0007] This invention provides a method for preparing a high-silver / zinc-loaded zirconium phosphate antibacterial agent, comprising the following steps:

[0008] (1) Preparation of zirconium phosphate support

[0009] Zirconium oxychloride was added to a phosphoric acid solution with a concentration of 3-12 mol / L and stirred. The mixture was then transferred to an oil bath with a reflux device installed. The reaction was carried out at 80-150℃ for 12-48 h. The reaction product was filtered, washed until neutral, and dried to obtain zirconium phosphate support.

[0010] (2) Preparation of intercalated zirconium phosphate

[0011] The zirconium phosphate support is added to an aqueous solution of intercalating agent with a concentration of 1-3 mol / L at a molar ratio of zirconium phosphate to intercalating agent of 2-5:1. After stirring, filtration, and drying, intercalated zirconium phosphate is obtained. The intercalating agent is one or a combination of aniline, n-butylamine, n-heptylamine, n-decanylamine, octadecyl alcohol, eicosanool, triacontanol, 2-methylpyridine, and 2-ethylpyridine.

[0012] (3) Ion exchange

[0013] According to the molar ratio of metal ions: Zr 4+ =1~6:7, the intercalated zirconium phosphate is dispersed in a metal ion solution with a concentration of 1~3 mol / L and stirred for 5~12 h for ion exchange. The metal ion solution is a silver salt solution, a zinc salt solution, or a mixture of silver salt solution and zinc salt solution. The obtained product is filtered, washed until neutral, and dried to obtain the silver / zinc-loaded zirconium phosphate precursor.

[0014] (4) Preparation of zirconium phosphate antibacterial agent

[0015] The silver / zinc loaded zirconium phosphate precursor was calcined at 900–1200°C for 1–3 hours, and then ground to obtain a high silver / zinc loaded zirconium phosphate antibacterial agent.

[0016] Furthermore, the mixture of silver salt solution and zinc salt solution in step (3) of the present invention is prepared with a molar ratio of silver:zinc = 1:1 to 5. The silver salt is silver acetate or silver nitrate, and the zinc salt is zinc nitrate, zinc acetate, zinc sulfate, or zinc chloride.

[0017] The present invention has the following beneficial effects:

[0018] (1) This invention utilizes zirconium phosphate, a solid acid with a strong affinity for Brønsted bases, to insert guests such as alkylamines, alkanols, and pyridines into the interlayer region while maintaining the integrity of its layered structure. This enables the exchange and loading of metal ions at room temperature in a short time. By adjusting the molar ratio of metal ions to zirconium, antibacterial agents with a silver loading of 1-20%, a zinc loading of 1-20%, and a silver-zinc co-loaded silver and zinc content of 1-28% (of which the silver content is 1-14% and the zinc content is 1-14%) can be accurately prepared.

[0019] (2) The present invention performs metal ion detection on the filtrate obtained by ion exchange loading and filtration in step (3). The utilization rate of metal ions reaches 100%, and there is no need to recover metal ions, which improves the utilization rate of raw materials and reduces production costs.

[0020] (3) The process of preparing zirconium phosphate antibacterial agent with high silver / zinc loading in this invention has a short ion exchange time, the metal ions can be completely exchanged, the raw material utilization rate is high, and the production process is simple.

[0021] The present invention will now be described in further detail with reference to embodiments. Detailed Implementation

[0022] Example 1:

[0023] This embodiment describes a method for preparing a high-silver / zinc-loaded zirconium phosphate antibacterial agent, the steps of which are as follows:

[0024] (1) Preparation of zirconium phosphate support

[0025] 4 g of zirconium oxychloride was added to 40 mL of 3 mol / L phosphoric acid solution and stirred. The mixture was then transferred to an oil bath and fitted with a reflux device. The reaction was carried out at 120 °C for 24 h. The reaction product was filtered, washed until neutral, and dried at 80 °C for 12 h to obtain zirconium phosphate support.

[0026] (2) Preparation of intercalated zirconium phosphate

[0027] The above zirconium phosphate support was added to an octadecyl alcohol aqueous solution with a concentration of 1 mol / L, and the reaction was stirred for 5 h. After filtration, washing and drying, intercalated zirconium phosphate was obtained.

[0028] (3) Ion exchange

[0029] According to the molar ratio Ag + ∶Zr 4+ =1:7, the above intercalated zirconium phosphate was dispersed in silver acetate solution (concentration of 1 mol / L) and stirred for 5 h for ion exchange. The resulting product was filtered, washed until neutral and dried to obtain silver-loaded zirconium phosphate precursor.

[0030] (4) Preparation of zirconium phosphate antibacterial agent

[0031] The above-mentioned silver-loaded zirconium phosphate precursor was placed in a muffle furnace and calcined at 1000℃ for 1 hour. After grinding and pulverizing, the high-silver-loaded zirconium phosphate antibacterial agent was obtained.

[0032] Example 2:

[0033] This embodiment describes a method for preparing a high silver / zinc loaded zirconium phosphate antibacterial agent, which differs from Embodiment 1 in that: in step (2), the intercalating agent is n-decanamine, and in step (3), the molar ratio of Ag is... + ∶Zr 4+ =2∶7.

[0034] Example 3:

[0035] This embodiment describes a method for preparing a high silver / zinc loaded zirconium phosphate antibacterial agent, which differs from Embodiment 1 in that: in step (2), the intercalating agent is 2-methylpyridine, and in step (3), the molar ratio of Ag is... + ∶Zr 4+ =3∶7.

[0036] Example 4:

[0037] This embodiment describes a method for preparing a high silver / zinc loaded zirconium phosphate antibacterial agent, which differs from Embodiment 1 in that: in step (3), the molar ratio of Ag is... + ∶Zr4+ =4∶7.

[0038] Example 5:

[0039] This embodiment describes a method for preparing a high-silver / zinc-loaded zirconium phosphate antibacterial agent, the steps of which are as follows:

[0040] (1) Preparation of zirconium phosphate support

[0041] 4 g of zirconium oxychloride was added to 40 mL of 3 mol / L phosphoric acid solution and stirred. The mixture was then transferred to an oil bath and fitted with a reflux device. The reaction was carried out at 120 °C for 24 h. The reaction product was filtered, washed until neutral, and dried at 80 °C for 12 h to obtain zirconium phosphate support.

[0042] (2) Preparation of intercalated zirconium phosphate

[0043] The above zirconium phosphate support was added to an octadecyl alcohol aqueous solution with a concentration of 1 mol / L, and the reaction was stirred for 5 h. After filtration, washing and drying, intercalated zirconium phosphate was obtained.

[0044] (3) Ion exchange

[0045] According to the molar ratio (Ag) + +Zn 2+ )∶Zr 4+ =2∶7, the above intercalated zirconium phosphate was dispersed in a mixture of silver acetate solution (concentration of 1 mol / L) and zinc acetate solution (concentration of 1 mol / L) (according to the molar ratio Ag) + ∶Zn 2+ In a mixture of 1:1, the reaction was stirred for 5 hours to carry out ion exchange. The resulting product was filtered, washed until neutral, and dried to obtain the silver / zinc zirconium phosphate precursor.

[0046] (4) Preparation of zirconium phosphate antibacterial agent

[0047] The above-mentioned silver / zinc loaded zirconium phosphate precursor was placed in a muffle furnace and calcined at 1000℃ for 1 hour. After grinding and pulverizing, the high silver and zinc loaded zirconium phosphate antibacterial agent was obtained.

[0048] Example 6:

[0049] This embodiment describes a method for preparing a high silver / zinc loaded zirconium phosphate antibacterial agent, which differs from Embodiment 5 in that: in step (2), the intercalating agent is n-decanamine, and in step (3), the molar ratio (Ag) is... + +Zn 2+ )∶Zr 4+ =4∶7.

[0050] Example 7:

[0051] This embodiment describes a method for preparing a high silver / zinc loaded zirconium phosphate antibacterial agent, which differs from Embodiment 5 in that: in step (2), the intercalating agent is 2-methylpyridine, and in step (3), the molar ratio (Ag) is... + +Zn 2+ )∶Zr 4+ =6∶7.

[0052] Example 8:

[0053] This embodiment describes a method for preparing a high silver / zinc loaded zirconium phosphate antibacterial agent, which differs from Embodiment 1 in that: in step (3), the intercalated zirconium phosphate is dispersed in a zinc acetate solution (concentration of 1 mol / L), according to the molar ratio of Zn... + ∶Zr 4+ =4∶7.

[0054] Comparative Examples 1 and 2 were respectively prepared using zirconium phosphate without step (2) of Example 1 and Example 5 (other steps were the same). The test results of the silver / zinc loading of the zirconium phosphate antibacterial agents prepared in the examples and comparative examples of the present invention are shown in Table 1.

[0055] Table 1. Test results of silver / zinc loading of zirconium phosphate antibacterial agents prepared in the embodiments and comparative examples of the present invention.

[0056]

[0057] Table 1 shows that in Examples 1, 2, 3, and 4 of the present invention, when silver ions are loaded alone, the silver loading increases with the increase of silver ion concentration, reaching 19.85%. In Examples 5, 6, and 7, when silver and zinc are loaded together, the silver and zinc loadings also increase with the increase of silver and zinc ion concentrations, reaching 13.44% and 13.71% respectively. In Example 8, when zinc ions are loaded alone, the zinc loading reaches 19.89%.

[0058] The carriers used in Comparative Examples 1 and 2 were unintercalated zirconium phosphate carriers. Silver and zinc ions could not easily exchange with hydrogen ions between the layers in a short time, and the silver and zinc loadings (both less than 1%) were far lower than those in the embodiments of the present invention.

[0059] The filtrate obtained after ion exchange loading and filtration in step (3) of this embodiment of the invention was tested for silver and zinc ions. A certain amount of NaCl was added to 5 mL of the filtrate; no white AgCl precipitate was observed, indicating that AgCl... +The entire solution was loaded into zirconium phosphate. 5 mL of the filtrate was added to excess NaOH, resulting in a strongly alkaline solution. Adding one drop of sodium sulfide further resulted in no white precipitate, indicating no zinc ion residue in the filtrate. This invention achieves 100% utilization of silver and zinc ions without the need for recovery, thus improving raw material utilization and reducing production costs.

Claims

1. A method for preparing a high silver / zinc loaded zirconium phosphate antibacterial agent, characterized in that... Includes the following steps: (1) Preparation of zirconium phosphate support Zirconium oxychloride was added to a phosphoric acid solution with a concentration of 3-12 mol / L and stirred. The mixture was then transferred to an oil bath with a reflux device installed. The reaction was carried out at 80-150℃ for 12-48 h. The reaction product was filtered, washed until neutral, and dried to obtain zirconium phosphate support. (2) Preparation of intercalated zirconium phosphate The zirconium phosphate support is added to an intercalating agent solution with a concentration of 1-3 mol / L according to a molar ratio of zirconium phosphate to intercalating agent = 2-5:

1. After stirring, filtration, and drying, intercalated zirconium phosphate is obtained. The intercalating agent is one or a combination of octadecyl alcohol, eicosanool, triacontanol, 2-methylpyridine, and 2-ethylpyridine. (3) Ion exchange According to the molar ratio of metal ions: Zr 4+ The intercalated zirconium phosphate was dispersed in a metal ion solution with a concentration of 1-3 mol / L and stirred for 5-12 hours for ion exchange. The metal ion solution was a silver salt solution, a zinc salt solution, or a mixture of silver salt solution and zinc salt solution, wherein the molar ratio of silver to zinc in the mixture was 1:1-5. The resulting product was filtered, washed until neutral, and dried to obtain a silver / zinc-loaded zirconium phosphate precursor with a metal ion utilization rate of 100%. (4) Preparation of zirconium phosphate antibacterial agent The silver / zinc-loaded zirconium phosphate precursor was calcined at 900–1200°C for 1–3 hours, and then ground to obtain a high silver / zinc-loaded zirconium phosphate antibacterial agent. The antibacterial agent has a silver loading of 5.28–20%, a zinc loading of up to 19.98%, and a silver-zinc co-loaded antibacterial agent with a silver and zinc content of 11.29–28%. In the silver-zinc co-loaded antibacterial agent, the silver content is 5.39–14% and the zinc content is 5.9–14%.

2. The method for preparing the high silver / zinc loaded zirconium phosphate antibacterial agent according to claim 1, characterized in that: The silver salt is silver acetate or silver nitrate, and the zinc salt is zinc nitrate, zinc acetate, zinc sulfate, or zinc chloride.

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