CN103736406A - Anti-pollution and easily-washable polyamide reverse osmosis composite membrane and preparation method of membrane - Google Patents

Anti-pollution and easily-washable polyamide reverse osmosis composite membrane and preparation method of membrane Download PDF

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CN103736406A
CN103736406A CN201310756414.2A CN201310756414A CN103736406A CN 103736406 A CN103736406 A CN 103736406A CN 201310756414 A CN201310756414 A CN 201310756414A CN 103736406 A CN103736406 A CN 103736406A
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reverse osmosis
osmosis composite
polyamide reverse
membrane
composite film
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CN103736406B (en
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孟建强
杜西兰
曹震
张宇峰
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Tianjin Polytechnic University
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Abstract

The invention discloses an anti-pollution and easily-washable polyamide reverse osmosis composite membrane and a preparation method of the membrane. The method disclosed by the invention comprises the following steps: (1) sequentially washing a polyamide reverse osmosis composite membrane by using isopropanol and de-ionized water; (2) adding the washed polyamide reverse osmosis composite membrane, 4-(2-sulfoethyl)-1-(4-vinyl benzyl)pyridine glycine betaine, potassium thiosulfate, sodium hydrogen sulfite and de-ionized water into a container; introducing nitrogen and discharging oxygen in the container; and (3) sealing the container and carrying out reaction in a water bath. The method is simple and convenient, conditions are moderate and the environment-friendly effect is realized; the prepared anti-pollution and easily-washable polyamide reverse osmosis composite membrane has the strong anti-pollution capability; after being polluted, the surface of the membrane can be physically washed by changing the salt concentration of input water; an organic chemical washing agent is not needed; the durability of the membrane is improved; the cost is reduced and the service life of the membrane is prolonged.

Description

Polyamide reverse osmosis composite film of a kind of antipollution easy cleaning and preparation method thereof
Technical field
The present invention relates to polyamide reverse osmosis composite film of a kind of antipollution easy cleaning and preparation method thereof.
Background technology
Along with quickening and the population growth of social industrialization paces, shortage of fresh water becomes one of facing mankind to be threatened greatly, and desalinization becomes the critical path of head it off.Conventional biochemical isolation technics products of separated purity is not high, energy consumption is large, is difficult to effectively carry out Selective Separation, and often causes comparatively serious secondary pollution.Membrane separation technique is the separation technology developing rapidly after the sixties in 20th century, the effect that have separation, concentrates, purifies.Reverse osmosis technology is a kind of reliable separation method of economy that solves water crisis, has been widely used in seawater and brackish water desalination, and waste water reclaims and pure water manufacture.Film, as the core component of membrane separation technique, has Selective Separation function, yet film pollutes the performance and used life that greatly affects film, has increased the use cost of film.
Commercial polyamide reverse osmosis composite film is to take porous polysulfones as supporting layer, and p-phenylenediamine (PPD) and pyromellitic trimethylsilyl chloride interfacial polymerization form composite bed.Polyamide reverse osmosis composite film has that excellent chemical stability, high water flux and salt are held back, high temperature resistant, withstand voltage and acid and alkali-resistance.But polluting to become, film affects the subject matter that film can better be applied.The surface roughness of reverse osmosis composite membrane, surface hydrophilicity and surface charge are the principal elements that affects membrane separating property.At present, to polyamide reverse osmosis composite film, modification is mainly following three performances of improving film: (1) surface roughness; (2) parent/hydrophobic performance; (3) surface charge.Coarse film surface has larger effective infiltrating area, and the infiltration that can improve film can aggravate colloid and the biological pollution to film but increase film surface roughness; The film surface of good hydrophilic property is conducive to improve permeation flux and the antifouling property of film; The charging characteristic on film surface can affect the separating property of film to charge species, and film properties affected by pH larger, neutral-surface can be resisted various charged contaminants conventionally, has good antifouling property.
Film modification comprises after being prepared film forming after base material modification and first base material being adopted certain film-forming method to prepare film forming carries out surface modification to film again.A kind of NEW TYPE OF COMPOSITE membrane material that does not substantially change structure and the performance of body and there is functionalized surface of membrane surface modification intention preparation, and membrane surface modification has consequence in film industry.Membrane surface modification mainly comprises the methods such as coating, irradiation grafting modification, plasma graft and ATRP.Surface applies the category that belongs to physical modification, and the method is simple, but surface coating layer is easy to come off, therefore very restricted in application; Irradiation grafting modification is a kind of important surface graft modification method, have the advantages such as safe, pollution-free and easy and simple to handle, but irradiation can cause homopolymerization and the degraded of monomer; Plasma modification technology has lot of advantages, can fast and effeciently give the performance that material is new, and only change the character of material surface, body is not had to impact substantially, but Cement Composite Treated by Plasma can change and decay along with the time, made modified effect unstable.ATRP is the method for extensive use the most in activity/controllable free radical polymerization, have easy and simple to handle, monomeric species is many, mild condition, advantages of environment protection, is successfully applied to the modification of material in recent years.
Amphoteric ion polymer has hydrophilic yin, yang ionic group, as-OH ,-COOH ,-SO 3thereby Deng and be not subject to pH impact and make it have unique stable against biological contamination performance, absorption, bacterial adhesion and biomembranous formation that can impedance nonspecific proteins matter, this specific character makes this type of material more and more be applied in association areas such as biomedicines.Up to now, people have synthesized the amphoteric ion polymer of a lot of novel functionalization and have been applied to the every field such as the synthetic and sewage disposal of petroleum industry, bio-medical material, medicine.
Summary of the invention
The polyamide reverse osmosis composite film that the object of this invention is to provide a kind of antipollution easy cleaning.
Second object of the present invention is to provide the preparation method of a kind of mild condition, antipollution easy cleaning polyamide reverse osmosis composite film simple to operate.
Technical scheme of the present invention is summarized as follows:
A polyamide reverse osmosis composite film for antipollution easy cleaning, at poly-4-(2-sulfoethyl)-1-(4-vinyl benzyl) pyridine betaine of polyamide reverse osmosis composite film surface grafting.
A preparation method for the polyamide reverse osmosis composite film of antipollution easy cleaning, comprises the steps:
(1) polyamide reverse osmosis composite film is used successively isopropyl alcohol and washed with de-ionized water clean;
(2) polyamide reverse osmosis composite film, 4-(2-sulfoethyl)-1-(4-vinyl benzyl) pyridine betaine, potassium thiosulfate, sodium hydrogensulfite and deionized water after cleaning are joined in container, obtain 50-300 ml water solution, making 4-(2-sulfoethyl)-1-(4-vinyl benzyl) pyridine betaine concentration is 1-2mmolL -1, thiosulfuric acid potassium concn is 1-2mmolL -1, concentration of sodium bisulphite is 1-2mmolL -1, continue to pass into nitrogen 15-20min and get rid of the oxygen in container;
(3) airtight container, 20-70 ℃ of water-bath 1-24h, obtains a kind of polyamide reverse osmosis composite film of antipollution easy cleaning.
The present invention be by redox, cause radical polymerization method at polyamide reverse osmosis composite film surface grafting amphoteric ion polymer poly-(4-(2-sulfoethyl)-1-(4-vinyl benzyl) pyridine betaine) (PSVBP), the method has easy and simple to handle, mild condition, advantages of environment protection, and the polyamide reverse osmosis composite film contamination resistance of the antipollution easy cleaning preparing is strong, the salinity that can intake by change after pollution is carried out physical cleaning to film surface, without the need for chemical machine cleaning agent, improve the durability of film, this is by the expense and the ambient influnence that greatly reduce the required Chemical cleaning of common film and bring, extend the service life of film.
Accompanying drawing explanation
Fig. 1 is monomer 4-(2-sulfoethyl)-1-(4-vinyl benzyl) pyridine betaine (SVBP) nuclear-magnetism figure.
Fig. 2 is the FTIR figure of polyamide reverse osmosis composite film of the antipollution easy cleaning of polyamide reverse osmosis composite film, embodiment 2, embodiment 3 and embodiment 4 preparations, wherein: a is polyamide reverse osmosis composite film; B is the polyamide reverse osmosis composite film of the antipollution easy cleaning of embodiment 2 preparations, and c is the polyamide reverse osmosis composite film of the antipollution easy cleaning of embodiment 3 preparations, and d is the polyamide reverse osmosis composite film of the antipollution easy cleaning of embodiment 4 preparations.
Fig. 3 is the XPS figure of polyamide reverse osmosis composite film of the antipollution easy cleaning of polyamide reverse osmosis composite film, embodiment 2, embodiment 3 and embodiment 4 preparations, wherein: a is polyamide reverse osmosis composite film; B is the polyamide reverse osmosis composite film of the antipollution easy cleaning of embodiment 2 preparations, and c is the polyamide reverse osmosis composite film of the antipollution easy cleaning of embodiment 3 preparations, and d is the polyamide reverse osmosis composite film of the antipollution easy cleaning of embodiment 4 preparations.
Fig. 4 is pollution-self-cleaning flux pattern of polyamide reverse osmosis composite film.
Fig. 5 is pollution-self-cleaning flux pattern of a kind of antipollution easy cleaning polyamide reverse osmosis composite film of embodiment 2 preparations.
Fig. 6 is pollution-self-cleaning flux pattern of a kind of antipollution easy cleaning polyamide reverse osmosis composite film of embodiment 3 preparations.
Fig. 7 is pollution-self-cleaning flux pattern of a kind of antipollution easy cleaning polyamide reverse osmosis composite film of embodiment 4 preparations.
The specific embodiment
Below in conjunction with specific embodiment, the present invention is further illustrated.
Embodiment 1
The preparation of ampholytic monomer 4-(2-sulfoethyl)-1-(4-vinyl benzyl) pyridine betaine (SVBP), comprises the steps:
(1) get 18.72g(0.1mol) 2-(4-pyridine) ethyl sulfonic acid and 4g(0.1mol) NaOH is dissolved in 120ml formamide together with at room temperature;
(2) by 15.26g(0.1mol) 4-1-chloro-4-methyl-benzene and a nitrobenzene slowly splashes in formamide solution under nitrogen protection;
(3) under room temperature, stir 65h;
(4) reacted solution is cooled to 4 ℃ in refrigerator, and is deposited in ice acetone;
(5) filter, will leach thing vacuum drying in vacuum drying oven and obtain thick product;
(6) finally in ice absolute ethyl alcohol, crystallization obtains salt-free pure SVBP monomer.See Fig. 1.
Embodiment 2
A preparation method for the polyamide reverse osmosis composite film of antipollution easy cleaning, comprises the steps:
(1) polyamide reverse osmosis composite film is used successively isopropyl alcohol and washed with de-ionized water clean;
(2) 20cm * 5cm polyamide reverse osmosis composite film, 4-(2-sulfoethyl)-1-(4-vinyl benzyl) pyridine betaine, potassium thiosulfate, sodium hydrogensulfite and deionized water after cleaning are joined in container, obtain 100 ml water solution, making 4-(2-sulfoethyl)-1-(4-vinyl benzyl) pyridine betaine concentration is 1mmolL -1, thiosulfuric acid potassium concn is 2mmolL -1, concentration of sodium bisulphite is 2mmolL -1, continue to pass into nitrogen 20min and get rid of the oxygen in container;
(3) airtight container, 60 ℃ of water-bath 24h, take out film, and pure water cleans, and obtains a kind of polyamide reverse osmosis composite film of antipollution easy cleaning.By FTIR and XPS test, confirm being successfully prepared of film.See Fig. 2, Fig. 3.
Embodiment 3
A preparation method for the polyamide reverse osmosis composite film of antipollution easy cleaning, comprises the steps:
(1) polyamide reverse osmosis composite film is used successively isopropyl alcohol and washed with de-ionized water clean;
(2) 20cm * 5cm polyamide reverse osmosis composite film, 4-(2-sulfoethyl)-1-(4-vinyl benzyl) pyridine betaine, potassium thiosulfate, sodium hydrogensulfite and deionized water after cleaning are joined in container, obtain 50 ml water solution, making 4-(2-sulfoethyl)-1-(4-vinyl benzyl) pyridine betaine concentration is 2mmolL -1, thiosulfuric acid potassium concn is 1mmolL -1, concentration of sodium bisulphite is 1mmolL -1, continue to pass into nitrogen 15min and get rid of the oxygen in container;
(3) airtight container, 20 ℃ of water-bath 24h, take out film, and pure water cleans, and obtains a kind of polyamide reverse osmosis composite film of antipollution easy cleaning.By FTIR and XPS test, confirm being successfully prepared of film.See Fig. 2, Fig. 3.
Embodiment 4
A preparation method for the polyamide reverse osmosis composite film of antipollution easy cleaning, comprises the steps:
(1) polyamide reverse osmosis composite film is used successively isopropyl alcohol and washed with de-ionized water clean;
(2) 20cm * 5cm polyamide reverse osmosis composite film, 4-(2-sulfoethyl)-1-(4-vinyl benzyl) pyridine betaine, potassium thiosulfate, sodium hydrogensulfite and deionized water after cleaning are joined in container, obtain 300 ml water solution, making 4-(2-sulfoethyl)-1-(4-vinyl benzyl) pyridine betaine concentration is 2mmolL -1, thiosulfuric acid potassium concn is 2mmolL -1, concentration of sodium bisulphite is 2mmolL -1, continue to pass into nitrogen 20min and get rid of the oxygen in container;
(3) airtight container, 70 ℃ of water-bath 1h, take out film, and pure water cleans, and obtains a kind of polyamide reverse osmosis composite film of antipollution easy cleaning.By FTIR and XPS test, confirm being successfully prepared of film.See Fig. 2, Fig. 3.
Embodiment 5
Film Contamination measurement:
(1) weigh 100mg bovine serum albumin and 500mg NaCl in beaker, after dissolving with 50mL pure water, be settled in 1L volumetric flask;
(2) the antipollution easy cleaning polyamide reverse osmosis composite film respectively polyamide reverse osmosis composite film and embodiment 2-4 being prepared is fixed in laboratory self-control cross-flow device, with the NaCl solution of 500mg/L, at pressure, be precompressed 12h under 1.6Mpa, until flux stabilized.
(3) water flux of the BSA/NaCl solution testing film configuring with (1), interval is collected and is seen through liquid at regular intervals.
Salt response film cleaning step:
(1) film cleans and carries out front 2g/L NaCl measured in solution membrane flux and the rejection baseline used.
(2) with pure water, film is cleaned to 30min;
(3) the NaCl solution with 2mol/L cleans 30min to film;
(4) repeating step (2), (3);
(5) with 2g/L NaCl measured in solution membrane flux.
(6) flux computing formula is as follows:
J = Q A × Δt - - - ( 1 )
J-water flux (L/m 2h), Q-sees through volume (L), A-film effective area (m 2), the △ t-time (h).
The results are shown in Figure 4-Fig. 7.
By Fig. 4-Fig. 7, can be found out, increase in time, former polyamide reverse osmosis composite film and antipollution easy cleaning polyamide reverse osmosis composite film flux all reduce, but the contaminated degree of antipollution easy cleaning polyamide reverse osmosis composite film is less than former polyamide reverse osmosis composite film, and after supersalt is washed, flux recovery obtains more, illustrates that antipollution easy cleaning polyamide reverse osmosis composite film resistance tocrocking and easy cleaning are all better than former polyamide reverse osmosis composite film.

Claims (2)

1. a polyamide reverse osmosis composite film for antipollution easy cleaning, is characterized in that at poly-4-(2-sulfoethyl)-1-(4-vinyl benzyl) pyridine betaine of polyamide reverse osmosis composite film surface grafting.
2. the preparation method of the polyamide reverse osmosis composite film of a kind of antipollution easy cleaning of claim 1, is characterized in that comprising the steps:
(1) polyamide reverse osmosis composite film is used successively isopropyl alcohol and washed with de-ionized water clean;
(2) polyamide reverse osmosis composite film, 4-(2-sulfoethyl)-1-(4-vinyl benzyl) pyridine betaine, potassium thiosulfate, sodium hydrogensulfite and deionized water after cleaning are joined in container, obtain 50-300 ml water solution, making 4-(2-sulfoethyl)-1-(4-vinyl benzyl) pyridine betaine concentration is 1-2mmolL -1, thiosulfuric acid potassium concn is 1-2mmolL -1, concentration of sodium bisulphite is 1-2mmolL -1, continue to pass into nitrogen 15-20min and get rid of the oxygen in container;
(3) airtight container, 20-70 ℃ of water-bath 1-24h, obtains a kind of polyamide reverse osmosis composite film of antipollution easy cleaning.
CN201310756414.2A 2013-12-31 2013-12-31 Polyamide reverse osmosis composite film of a kind of antipollution easy cleaning and preparation method thereof Active CN103736406B (en)

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CN106731867A (en) * 2016-12-08 2017-05-31 厦门建霖工业有限公司 The preparation method and preparation facilities of a kind of efficient anti-pollution reverse osmosis membrane
CN113390865A (en) * 2021-06-07 2021-09-14 浙江工业大学 Quick, sensitive and nontoxic acid-base indicator paper, preparation method thereof and application thereof in biological and pharmaceutical detection
CN114177774A (en) * 2021-12-27 2022-03-15 杭州天创环境科技股份有限公司 Method for constructing anti-pollution coating of polyamide reverse osmosis composite membrane
CN114984782A (en) * 2022-08-02 2022-09-02 湖南沁森高科新材料有限公司 Anti-pollution polyamide reverse osmosis membrane with high flux and high desalination rate and preparation method thereof

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Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN106731867A (en) * 2016-12-08 2017-05-31 厦门建霖工业有限公司 The preparation method and preparation facilities of a kind of efficient anti-pollution reverse osmosis membrane
CN113390865A (en) * 2021-06-07 2021-09-14 浙江工业大学 Quick, sensitive and nontoxic acid-base indicator paper, preparation method thereof and application thereof in biological and pharmaceutical detection
CN114177774A (en) * 2021-12-27 2022-03-15 杭州天创环境科技股份有限公司 Method for constructing anti-pollution coating of polyamide reverse osmosis composite membrane
CN114177774B (en) * 2021-12-27 2024-05-31 杭州天创环境科技股份有限公司 Construction method of polyamide reverse osmosis composite membrane anti-pollution coating
CN114984782A (en) * 2022-08-02 2022-09-02 湖南沁森高科新材料有限公司 Anti-pollution polyamide reverse osmosis membrane with high flux and high desalination rate and preparation method thereof

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