阅读说明：本技术 一种稀土离子掺杂海藻酸钙/碳纳米管水凝胶抗菌过滤膜的制备方法 (Preparation method of rare earth ion doped calcium alginate/carbon nanotube hydrogel antibacterial filter membrane ) 是由 赵孔银 白甜 苗君萍 谢文宾 郭智龙 张越 谢慧珂 唐李文 胡云霞 于 2019-11-26 设计创作，主要内容包括：本发明公开了一种稀土离子掺杂海藻酸钙/碳纳米管水凝胶抗菌过滤膜的制备方法。首先将羧化碳纳米管与海藻酸钠一起溶解于水中得到铸膜液,将该铸膜液刮成膜并浸泡于可溶性钙盐水溶液中充分交联,得到一种含羧化碳纳米管的海藻酸钙水凝胶膜。钙离子可同时交联羧化碳纳米管上的羧基和海藻酸盐上的羧基,生成有机无机杂化材料,从而提高了海藻酸钙水凝胶的强度,降低了其溶胀性能。羧化碳纳米管赋予海藻酸钙水凝胶一定的抗菌性能。为了进一步提高水凝胶的抗菌性能和机械强度,将含羧化碳纳米管的海藻酸钙水凝胶过滤膜浸泡在稀土离子的溶液中进行二次交联,得到一种稀土离子掺杂海藻酸钙/碳纳米管水凝胶抗菌过滤膜。(The invention discloses a preparation method of a rare earth ion doped calcium alginate/carbon nano tube hydrogel antibacterial filter membrane. Firstly, dissolving the carboxylated carbon nanotubes and sodium alginate in water to obtain a membrane casting solution, scraping the membrane casting solution into a membrane, and soaking the membrane in a soluble calcium salt water solution for full crosslinking to obtain the calcium alginate hydrogel membrane containing the carboxylated carbon nanotubes. The calcium ions can simultaneously crosslink carboxyl on the carboxylated carbon nano tube and carboxyl on the alginate to generate the organic-inorganic hybrid material, thereby improving the strength of the calcium alginate hydrogel and reducing the swelling performance of the calcium alginate hydrogel. The carboxylated carbon nano tubes endow the calcium alginate hydrogel with certain antibacterial performance. In order to further improve the antibacterial performance and the mechanical strength of the hydrogel, the calcium alginate hydrogel filtering membrane containing the carboxylated carbon nanotubes is soaked in a rare earth ion solution for secondary crosslinking to obtain the rare earth ion doped calcium alginate/carbon nanotube hydrogel antibacterial filtering membrane.)

1. A preparation method of a rare earth ion doped calcium alginate/carbon nano tube hydrogel antibacterial filter membrane is characterized by comprising the following steps:

a) preparing a mixture water solution of the carboxylated carbon nano tube with the mass percentage concentration of 0.01-5%, then adding sodium alginate solid powder with the mass percentage concentration of 0.2-8% into the mixture water solution, stirring while adding, performing ultrasonic dispersion to obtain a mixture water solution of the carboxylated carbon nano tube and the sodium alginate, and standing and defoaming to obtain a casting solution;

b) preparing soluble calcium salt water solution with mass percent concentration of 0.2-20% as coagulating bath;

c) pouring the casting solution obtained in the step a) on a dry and clean glass plate, scraping the glass plate by using a glass rod with two ends wound with copper wires with the diameter of 20-1500 mu m, immediately putting the glass plate and the scraped film into the coagulating bath obtained in the step b) for soaking for 5-240min, reacting soluble calcium salt with sodium alginate to generate calcium alginate hydrogel, and simultaneously crosslinking carboxyl on carboxylated carbon nanotubes in the calcium alginate hydrogel to generate an organic-inorganic hybrid structure, and adding the physical enhancement effect of the carboxylated carbon nanotubes, so that the mechanical strength of the calcium alginate hydrogel is improved, and the swelling performance of the calcium alginate hydrogel is reduced; the carboxylated carbon nano tubes endow the calcium alginate hydrogel with antibacterial performance;

d) in order to further improve the antibacterial performance and mechanical strength of the hydrogel, the calcium alginate hydrogel membrane containing the carboxylated carbon nanotubes obtained in the step c) is soaked in an aqueous solution of rare earth ions with the mass percentage concentration of 0.1-5% for secondary crosslinking, so that the rare earth ion doped calcium alginate/carbon nanotube hydrogel antibacterial filtering membrane is obtained.

2. The method for preparing a rare earth ion doped calcium alginate/carbon nanotube hydrogel antibacterial filter membrane as claimed in claim 1, wherein the carboxylated carbon nanotubes are any one or a mixture of two or more of carboxylated single-walled carbon nanotubes, carboxylated double-walled carbon nanotubes and carboxylated multi-walled carbon nanotubes.

3. The method for preparing a rare earth ion doped calcium alginate/carbon nanotube hydrogel antibacterial filter membrane according to claim 1, wherein the soluble calcium salt is any one or a mixture of two or more of calcium chloride, calcium nitrate, calcium dihydrogen phosphate and calcium gluconate.

4. The method for preparing the rare earth ion-doped calcium alginate/carbon nanotube hydrogel antibacterial filtering membrane according to claim 1, wherein the rare earth ion is any one or a mixture of two or more of lanthanum ion, terbium ion, cerium ion, neodymium ion and samarium ion.

5. A preparation method of a rare earth ion doped calcium alginate/carbon nanotube hydrogel antibacterial filtering membrane is characterized in that a carboxylated carbon nanotube and rare earth ions endow the calcium alginate hydrogel filtering membrane with good antibacterial performance, so that the calcium alginate hydrogel filtering membrane is prevented from being degraded by bacteria in the use process; the structure of the calcium alginate hydrogel filtering membrane is changed by the crosslinking of the rare earth ions, and the pure water flux of the calcium alginate/carbon nano tube hydrogel antibacterial filtering membrane doped with the rare earth ions is 1.5-3 times of that of the calcium alginate filtering membrane.

6. The preparation method of the rare earth ion doped calcium alginate/carbon nano tube hydrogel antibacterial filtering membrane is characterized by being simple in preparation method and environment-friendly in preparation process, and the obtained rare earth ion doped calcium alginate/carbon nano tube hydrogel antibacterial filtering membrane has good pollution resistance and has good application prospects in dye desalination, brown sugar decolorization and protein purification.

Technical Field

The invention relates to a preparation method of a rare earth ion doped calcium alginate/carbon nano tube hydrogel antibacterial filtering membrane, belonging to the field of functional materials and membrane separation.

The invention relates to the technical fields of rare earth, antibiosis, a filter membrane, hydrogel and the like. In particular to a preparation method of a rare earth ion doped calcium alginate/carbon nano tube hydrogel antibacterial filter membrane.

Background

Common membrane filter materials such as Polyethylene (PE), polypropylene (PP), polyvinyl chloride (PVC), polyvinylidene fluoride (PVDF), clustering (PSF), etc. are very likely to cause adsorption of organic substances (proteins, etc.) on the surface and in membrane pores of the membrane, causing membrane pollution, resulting in severe attenuation of filtration flux, due to low surface energy and strong hydrophobicity. One approach to mitigate membrane fouling is to hydrophilize modify hydrophobic membranes to address this feature. Common hydrophilic modification methods include blending modification, surface coating modification, surface grafting modification and the like. However, these methods have problems that the modification process is complicated, the hydrophilic effect is unstable, or the bulk film is damaged during the production. More importantly, these methods cannot fundamentally solve the problem of hydrophilicity of the membrane and thus cannot fundamentally solve the contamination of the membrane. If the membrane body is made of hydrophilic substances, the pollution phenomenon caused by hydrophobicity does not exist. The polymer hydrogel is a hydrophilic substance which has a chemically or physically crosslinked structure, can absorb a large amount of water and can maintain a certain shape in water.

As industry has developed, water pollution has become a serious environmental problem. The development of new and potential functional materials is a meaningful attempt in water pollution treatment and is gradually developing as a research hotspot for water treatment. The hydrogel has high strengthThe efficient adsorption performance, low cost, no toxicity and other excellent characteristics attract the interest of researchers, and the method is widely applied to the field of water treatment. In conventional wastewater treatment processes, TiO₂Nanoparticles are generally utilized in the form of suspension systems because of the large surface area of their particles. However, suspended TiO in the wastewater₂The separation of nanoparticles necessarily increases operating costs and causes secondary pollution, thus greatly limiting its practical applications [ appl.catal.b, 2009, 88: 323-330 ]. Has explored and realized TiO₂Immobilization on different supports, such as glass, stainless steel plates, fibers, carbon nanotubes, polymers, etc. S.k.papageorgiou et al studied the photocatalytic/ultrafiltration removal process of toxic-containing wastewater. TiO 2₂The photocatalyst is effectively immobilized in the calcium alginate hollow fiber. Wang et al utilized hydrothermal method to produce Carbon Nanotubes (CNTs) and P-TiO at different ratios₂Synthesize CNTs/P-TiO₂Nano catalyst, this catalyst is TiO₂Has higher catalytic activity and wider spectral response range.

Carbon nanotubes are widely used in various fields due to their unique structures. In 2007, Kang et al in professor Elimelch of Yale university inspired from the toxicity of the nanotube, the interaction between SWNTS and bacteria was detected, and the result found that SWNTS exhibits excellent antibacterial performance. Subsequently, the laboratory has conducted a series of intensive studies on the antibacterial properties of the carbon nanotubes. Different from common chemical reagents, the carbon nanotube has different sizes, structures and appearances, and different preparation modes, impurities and chemical modifications can also cause the difference of the biological effect of the carbon nanotube cells. The physicochemical properties of the carbon nanotubes are closely related to the antibacterial activity exhibited by the carbon nanotubes.

The antibacterial effect of rare earth has attracted people's attention, and an external bactericide with the trade name of Ceriform is sold in the European market in 1906, the main chemical component of the bactericide is ceric potassium sulfate, and other cerium salts also have antibacterial ability. Jancso et al discovered that the neodymium and samarium compounds of the ferrotitanium reagent have anti-inflammatory properties, and then made them into ointment type medicines Phlog. Experiments show that Phlog has the maximum anti-inflammatory effect when the ratio of the rare earth to the ferrotitanium is 1: 2, and the ointment with the content of 3% has the best use effect. In recent years, a large number of researches show that the gargle containing 3% of neodymium sulfosalicylate and 0.1% of chlorhexidine is effective in inhibiting dental plaque, particularly has good effect on relieving gingival inflammation, and shows that rare earth ions have obvious anti-inflammatory effect. Rare earth compounds also often exhibit other superior bacteriostatic properties. For example, the ternary complex of camphorsulfonic acid, phenanthroline and rare earth has a stronger inhibitory effect on staphylococcus aureus, bacillus, pseudomonas aeruginosa, etc. than the corresponding ligand and binary complex.

The invention discloses a preparation method of a rare earth ion doped calcium alginate/carbon nano tube hydrogel antibacterial filter membrane. Firstly, dissolving the carboxylated carbon nanotubes and sodium alginate in water to obtain a membrane casting solution, scraping the membrane casting solution into a membrane, and soaking the membrane in a soluble calcium salt water solution for full crosslinking to obtain the calcium alginate hydrogel membrane containing the carboxylated carbon nanotubes. The calcium ions can simultaneously crosslink carboxyl on the carboxylated carbon nano tube and carboxyl on the alginate to generate the organic-inorganic hybrid material, thereby improving the strength of the calcium alginate hydrogel and reducing the swelling performance of the calcium alginate hydrogel. The carboxylated carbon nanotubes endow the calcium alginate hydrogel with antibacterial performance. In order to further improve the antibacterial performance and the mechanical strength of the hydrogel, the calcium alginate hydrogel filtering membrane containing the carboxylated carbon nanotubes is soaked in an aqueous solution of rare earth ions with the mass percentage concentration of 0.1-5% for secondary crosslinking, so that the rare earth ion doped calcium alginate/carbon nanotube hydrogel antibacterial filtering membrane is obtained.

Disclosure of Invention

Aiming at the defects of the prior art, the invention aims to solve the technical problems that the traditional filtering membrane has poor hydrophilicity, is not polluted, has low strength and is easy to degrade by bacteria.

The invention provides a preparation method of a rare earth ion-doped calcium alginate/carbon nano tube hydrogel antibacterial filter membrane, which solves the problems that the traditional filter membrane is poor in hydrophilicity and not pollution-resistant, and the calcium alginate hydrogel filter membrane is low in strength and easy to degrade by bacteria.

The invention provides a preparation method of a rare earth ion doped calcium alginate/carbon nano tube hydrogel antibacterial filter membrane, which is characterized by comprising the following steps:

a) preparing a mixture water solution of the carboxylated carbon nano tube with the mass percentage concentration of 0.01-5%, then adding sodium alginate solid powder with the mass percentage concentration of 0.2-8% into the mixture water solution, stirring while adding, performing ultrasonic dispersion to obtain a mixture water solution of the carboxylated carbon nano tube and the sodium alginate, and standing and defoaming to obtain a casting solution;

b) preparing soluble calcium salt water solution with mass percent concentration of 0.2-20% as coagulating bath;

c) pouring the casting solution obtained in the step a) on a dry and clean glass plate, scraping the glass plate by using a glass rod with two ends wound with copper wires with the diameter of 20-1500 mu m, immediately putting the glass plate and the scraped film into the coagulating bath obtained in the step b) for soaking for 5-240min, reacting soluble calcium salt with sodium alginate to generate calcium alginate hydrogel, and simultaneously crosslinking carboxyl on carboxylated carbon nanotubes in the calcium alginate hydrogel to generate an organic-inorganic hybrid structure, and adding the physical enhancement effect of the carboxylated carbon nanotubes, so that the mechanical strength of the calcium alginate hydrogel is improved, and the swelling performance of the calcium alginate hydrogel is reduced; the carboxylated carbon nano tubes endow the calcium alginate hydrogel with antibacterial performance;

d) in order to further improve the antibacterial performance and mechanical strength of the hydrogel, the calcium alginate hydrogel membrane containing the carboxylated carbon nanotubes obtained in the step c) is soaked in an aqueous solution of rare earth ions with the mass percentage concentration of 0.1-5% for secondary crosslinking, so that the rare earth ion doped calcium alginate/carbon nanotube hydrogel antibacterial filtering membrane is obtained.

The carboxylated carbon nanotube is any one or a mixture of two or more of carboxylated single-wall carbon nanotube, carboxylated double-wall carbon nanotube and carboxylated multi-wall carbon nanotube; the soluble calcium salt is any one or mixture of two or more of calcium chloride, calcium nitrate, calcium dihydrogen phosphate and calcium gluconate; the rare earth ions are any one or a mixture of two or more of lanthanum ions, terbium ions, cerium ions, neodymium ions and samarium ions.

The carboxylated carbon nanotubes and the rare earth ions endow the calcium alginate hydrogel filtering membrane with good antibacterial performance, and the calcium alginate hydrogel filtering membrane is prevented from being degraded by bacteria in the using process; the structure of the calcium alginate hydrogel filtering membrane is changed by the crosslinking of the rare earth ions, and the pure water flux of the calcium alginate/carbon nano tube hydrogel antibacterial filtering membrane doped with the rare earth ions is 1.5-3 times of that of the calcium alginate filtering membrane.

The preparation method is simple, the preparation process is green and environment-friendly, and the obtained rare earth ion doped calcium alginate/carbon nanotube hydrogel antibacterial filtering membrane has good pollution resistance and has good application prospects in dye desalination, brown sugar decolorization and protein purification.

Detailed Description

Specific examples of the present invention will be described below, but the present invention is not limited to the examples.