CN103816817A - Alkali-resistant cellulose membrane and preparation method thereof - Google Patents
Alkali-resistant cellulose membrane and preparation method thereof Download PDFInfo
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- CN103816817A CN103816817A CN201410041578.1A CN201410041578A CN103816817A CN 103816817 A CN103816817 A CN 103816817A CN 201410041578 A CN201410041578 A CN 201410041578A CN 103816817 A CN103816817 A CN 103816817A
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Abstract
本发明涉及一种耐碱纤维素膜及其制备方法，其特征在于该耐碱再生纤维素膜包括耐碱再生纤维素超滤膜和耐碱再生纤维素纳滤膜，也包括耐碱再生纤维素中空纤维膜和耐碱再生纤维素平板膜，是采用含5～15wt%水的NMMO为溶剂直接溶解纤维素浆粕和添加剂，然后采用浸沉凝胶相转化法纺制成再生纤维素膜，再经氢氧化钠后处理、水洗、甘油后处理而制得。制备的耐碱再生纤维素膜的孔径大于0.001μm，小于0.1μm，能截留有机物的分子量＞500MW。本发明可用于粘胶纤维的压榨废水，碱法造纸的黑液，印染工业的煮纱、丝光洗水，制革工业的灰碱脱毛废水和石油、化工部分生产过程的废水处理等。The invention relates to an alkali-resistant cellulose membrane and a preparation method thereof, characterized in that the alkali-resistant regenerated cellulose membrane includes an alkali-resistant regenerated cellulose ultrafiltration membrane and an alkali-resistant regenerated cellulose nanofiltration membrane, and also includes an alkali-resistant regenerated fiber Plain hollow fiber membranes and alkali-resistant regenerated cellulose flat membranes use NMMO containing 5-15wt% water as a solvent to directly dissolve cellulose pulp and additives, and then spin regenerated cellulose membranes by immersion gel phase inversion method. It is obtained after sodium hydroxide post-treatment, water washing and glycerin post-treatment. The pore size of the prepared alkali-resistant regenerated cellulose membrane is greater than 0.001 μm and less than 0.1 μm, and the molecular weight of the organic matter that can be intercepted is greater than 500 M W . The present invention can be used for pressing waste water of viscose fiber, black liquor of alkaline papermaking, yarn cooking and mercerizing washing water in printing and dyeing industry, ash alkali dehairing waste water in tanning industry and waste water treatment in some production processes of petroleum and chemical industry, etc.
Description
Technical field
The present invention relates to a kind of alkali resistant cellulose film and preparation method thereof.
Background technology
Alkaline waste water refers to and contains certain bases, pH value higher than 9 waste water, is divided into strong basicity waste water, alkalescent waste water, low concentration alkali wastewater and high concentration alkali wastewater.In alkaline waste water, except the alkali that contains certain variable concentrations, conventionally also contain a large amount of harmful substances such as organic matter, inorganic salts.The wide material sources of alkaline waste water, mainly from the squeezing waste water of viscose rayon, the black liquor of alkali paper-making, printing and dyeing industry boil yarn, mercerising wash water, the waste water of the ash alkali unhairing waste water of leather industry and oil, chemical industry part producing process etc.The processing method of alkaline waste water has acid-base neutralization method, flocculence, chemical precipitation method, combustion method, crystallisation, microbial method, electroosmose process etc.Embrane method water treatment with its have efficiently, the advantage such as practical, adjustable, energy-conservation and simple process is expected to be widely used in containing alkali waste water processing.
Cellulose has the advantages such as wide material sources, good biocompatibility, physical and chemical performance are stable, acid and alkali-resistance, is considered to desirable membrane material.Conventionally cellulose membrane is used to the fields such as desalinization, haemodialysis, gas separation, water-oil separating, packaging film.The preparation method of cellulose membrane has viscose process, cuprammonium process and solvent method.The Dalian Chemistry and Physics Institute of the Chinese Academy of Sciences is at application study (China and foreign countries' energy of Cellulose Hollow Fiber Membrane prepared by Solvent Method, 2006,11(4)), compare the performance of solvent method and the prepared film of cuprammonium process, result represents no matter cellulose membrane prepared by solvent method is in the acidity or alkaline solution of higher concentration, all show good stability, and cellulose membrane alkali resistance prepared by cuprammonium process is poor, can be dissolved in 18% NaOH solution, be therefore necessary to develop solvent method and prepare cellulose membrane for containing alkali waste water processing.
Summary of the invention
The object of this invention is to provide a kind of preparation method of regenerated cellulose film, the method film-forming process is simple, solvent is recyclable, pollution-free, and this cellulose membrane alkaline resistance properties is good, can be used for containing alkali waste water processing.
For achieving the above object, the technical solution used in the present invention is:
Alkaline-resisting regenerated cellulose film comprises alkaline-resisting regenerated cellulose milipore filter and alkaline-resisting regenerated cellulose NF membrane, also comprise alkaline-resisting regenerated cellulose hollow fiber film and alkaline-resisting regenerated cellulose Flat Membrane, that adopting containing the NMMO of 5～15wt% water is the direct dissolving cellulos pulp of solvent and additive, then adopt and soak that gel phase conversion method is spun into regenerated cellulose hollow fiber film or curtain coating becomes regenerated cellulose Flat Membrane, then make through NaOH post processing, washing, glycerine post processing.
The preparation method of alkaline-resisting regenerated cellulose film of the present invention comprises the following steps:
1) preparation of casting solution: under 80～100 ℃ of conditions, the cellulose pulp that is 5～20:70～93.9:1～8:0.1～2 by percentage by weight, evenly mix containing NMMO, additive and the antioxidant of 5～15wt% water, stir, dissolve, deaeration is filtered, and makes the cellulose casting solution of 5～20wt%;
2) the gel phase conversion method spinning film forming of soaking: under 70 ℃ of conditions, the casting solution that step 1) is made curtain coating on glass plate becomes Flat Membrane, or the casting solution that step 1) is made and core liquid are extruded tubular film by spinneret simultaneously; In the Flat Membrane making being solidified in entering coagulating bath after a gaseous environment is transferred set to 0～120S to 3～5min or tubular film being entered to coagulating bath after the gaseous environment of 0～20cm, solidify; Wash away the residual solvent in this film by deionized water again;
3) under 20～30 ℃ of conditions, with 17～22wt% sodium hydrate aqueous solution treatment step 2) cellulose membrane 45～100min of preparing;
4) after the cellulose membrane washing of being prepared by step 3), be immersed in 3～24h in the glycerine water solution of 10～50wt%, then film taken out to room temperature and dried and make regenerated cellulose film.
Described cellulose pulp is one or both the mixture in absorbent cotton, bamboo pulp, wood pulps, reed straw, wheat straw waste, rice straw, sugarcane stalk;
The described cellulose pulp degree of polymerization is 500～1200, alpha-cellulose content >=90wt%;
Described antioxidant is n-propyl gallate;
Described additive is the mixture of macromolecule pore former, little molecule pore former;
Described macromolecule pore former and the weight ratio of little molecule pore former are 1～5:1;
Described macromolecule pore former is one or both the mixture in polyvinylpyrrolidone, polyethylene glycol, and polyvinylpyrrolidone model is selected from K12, K17, K25, K30, K60, K90, and molecular weight polyethylene glycol is 200-20000;
Described little molecule pore former is the one in glycerine, formamide;
Described core liquid is the one in the glycerine water solution of water, 1～20wt%;
In described gaseous environment, gas is the one in air, nitrogen, argon gas, and air gap temperature is 24 ℃, and humidity is 30～90%RH;
Described coagulating bath is water, contains the one in NMMO, 5～50wt% formamide aqueous solution of 5～50wt% water, and temperature is 10～50 ℃.
Alkaline-resisting regenerated cellulose film tool of the present invention has the following advantages:
1) filming technology of the present invention is simple, pollution-free, solvent NMMO easily reclaims, and is friendly process.
2) cellulose pulp that the present invention uses is not high to the content requirement of alpha-cellulose, can reduce the preparation cost of cellulose pulp, expands the source range that comes of raw material.
3) NaOH post processing can reduce the content of the impurity such as hemicellulose, lignin in cellulose membrane, makes the content of alpha-cellulose in regenerated cellulose film high as much as possible; The method can also change the pore structure of cellulose membrane, provides an approach for preparing porous cellulose film.
4) the present invention has added macromolecule pore former and little molecule pore former preparing in regenerated cellulose casting solution, by the compounded combination of macromolecule pore former and little molecule pore former, regulate and control respectively or synergistically the pore structure of cellulose membrane, make the aperture of regenerated cellulose film be greater than 0.001 μ m, be less than 0.1 μ m, can hold back organic molecular weight > 500M
w.
5) the alkaline-resisting regenerated cellulose film that prepared by the present invention can be used for the squeezing waste water of viscose rayon, the black liquor of alkali paper-making, printing and dyeing industry boil yarn, mercerising wash water, the wastewater treatment of the ash alkali unhairing waste water of leather industry and oil, chemical industry part producing process etc.
The specific embodiment
embodiment 1
At 80 ℃, be 1200 by the 5g degree of polymerization, alpha-cellulose content is the reed straw of 90wt%, 0.83gPVP-K90,0.17g glycerine, 0.1g n-propyl gallate and 93.9g are containing the NMMO solvent of 15wt% water, and uniform stirring makes its dissolving, approximately need 1h, deaeration makes the cellulose casting solution of 5wt% after filtering; At 70 ℃, this casting solution curtain coating on glass plate is become to Flat Membrane, this film is put into deionized water at once and solidify 5min; After washing by this film under 30 ℃ of conditions, process 45min with 17wt% sodium hydrate aqueous solution, then after washing, this film soaked to 3h with 30wt% glycerine water solution, then this film is dried and makes regenerated cellulose flat plate ultrafiltration membrane in air at room temperature.The water flux of this film is 637L/m
2h is 98% to the rejection of 1% bovine serum albumin.
embodiment 2
At 100 ℃, be 912 by the 20g degree of polymerization, the bamboo pulp that alpha-cellulose content is 93wt%, 4gPEG8000,4g glycerine, 2g n-propyl gallate and 70g are containing the NMMO solvent of 5wt% water, uniform stirring dissolves it, approximately needs 2h, and deaeration makes the cellulose casting solution of 20wt% after filtering; At 70 ℃, this casting solution and 20wt% glycerine water solution are extruded into tubular film jointly through spinneret, by 24 ℃ of this film process 15cm, after the argon gas air gap of 90%RH, enter 50 ℃, solidify containing in the NMMO solvent of 10wt% water; After washing by this film under 25 ℃ of conditions, process 100min with 22wt% sodium hydrate aqueous solution, then soak this film 24h with 10wt% glycerine water solution after washing, then this film is dried and makes regenerated cellulose hollow fiber NF membrane in air at room temperature.The water flux of this film is 234L/m
2h, to the rejection of the impurity such as hemicellulose in viscose rayon squeezing waste water up to 98%.
embodiment 3
At 90 ℃, be 500 by the 24g degree of polymerization, alpha-cellulose content is the wood pulps of 92wt%, 3.75gPVP-K30,1.25g formamide, 2g n-propyl gallate and 169g are containing the NMMO solvent of 10wt% water, and uniform stirring makes its dissolving, approximately need 1.5h, deaeration makes the cellulose casting solution of 12wt% after filtering; At 70 ℃, this casting solution and 1wt% glycerine water solution are extruded into tubular film jointly through spinneret, put into immediately 30 ℃, in the 5wt% formamide aqueous solution, solidify; After washing by this film under 20 ℃ of conditions, process 60min with 20wt% sodium hydrate aqueous solution, then soak this film 15h with 30wt% glycerine water solution after washing, then this film is dried and makes regenerated cellulose hollow fiber milipore filter in air at room temperature.The water flux of this film is 532L/m
2h is 99% to the rejection of 1% bovine serum albumin.
Claims (9)
1. an alkali resistant cellulose film, it is characterized in that this film comprises alkali resistant cellulose hollow-fibre membrane and alkali resistant cellulose Flat Membrane, that adopting containing the NMMO of 5～15wt% water is the direct dissolving cellulos pulp of solvent and additive, then adopt and soak that gel phase conversion method is spun into regenerated cellulose hollow fiber film or curtain coating becomes regenerated cellulose Flat Membrane, then make through NaOH post processing, washing, glycerine post processing.
2. the preparation method of a kind of alkali resistant cellulose film according to claim 1, is characterized in that the method comprises the following steps:
1) preparation of casting solution: under 80～100 ℃ of conditions, the cellulose pulp that is 5～20:70～93.9:1～8:0.1～2 by percentage by weight, evenly mix containing NMMO, additive and the antioxidant of 5～15wt% water, stir, dissolve, deaeration is filtered, and makes the cellulose casting solution of 5～20wt%;
2) the gel phase conversion method spinning film forming of soaking: under 70 ℃ of conditions, the casting solution that step 1) is made curtain coating on glass plate becomes Flat Membrane, or the casting solution that step 1) is made and core liquid are extruded tubular film by spinneret simultaneously; In the Flat Membrane making being solidified in entering coagulating bath after a gaseous environment is transferred set to 0～120S to 3～5min or tubular film being entered to coagulating bath after the gaseous environment of 0～20cm, solidify; Wash away the residual solvent in this film by deionized water again;
Described core liquid is the one in the glycerine water solution of water, 1～20 wt%;
Described coagulating bath is water, contains the one in NMMO, 5～50wt% formamide aqueous solution of 5～50wt% water, and temperature is 10～50 ℃;
3) under 20～30 ℃ of conditions, with 17～22wt% sodium hydrate aqueous solution treatment step 2) cellulose membrane 45～100min of preparing;
4) after the cellulose membrane washing of being prepared by step 3), be immersed in 3～24h in the glycerine water solution of 10～50wt%, then film taken out to room temperature and dried and make alkali resistant cellulose film.
3. the preparation method of a kind of alkali resistant cellulose film according to claim 1 and 2, is characterized in that described cellulose pulp is one or both the mixture in absorbent cotton, bamboo pulp, wood pulps, reed straw, wheat straw waste, rice straw, sugarcane stalk.
4. the preparation method of a kind of alkali resistant cellulose film according to claim 1 and 2, is characterized in that the described cellulose pulp degree of polymerization is 500～1200, alpha-cellulose content >=90wt%.
5. the preparation method of a kind of alkali resistant cellulose film according to claim 1 and 2, is characterized in that described additive is the mixture of macromolecule pore former, little molecule pore former.
6. the preparation method of a kind of alkali resistant cellulose film according to claim 6, is characterized in that described macromolecule pore former and the weight ratio of little molecule pore former are 1～5:1.
7. the preparation method of a kind of alkali resistant cellulose film according to claim 6, it is characterized in that described macromolecule pore former is one or both the mixture in polyvinylpyrrolidone, polyethylene glycol, polyvinylpyrrolidone model is selected from K12, K17, K25, K30, K60, K90, and molecular weight polyethylene glycol is 200-20000.
8. a kind of alkali resistant cellulose film according to claim 6, is characterized in that described little molecule pore former is the one in glycerine, formamide.
9. the preparation method of a kind of alkali resistant cellulose film according to claim 2, is characterized in that step 2) described in gaseous environment in gas be the one in air, nitrogen, argon gas, air gap temperature is 24 ℃, humidity is 30～90%RH.
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| CN105597551A (en) * | 2015-10-16 | 2016-05-25 | 福建农林大学 | Production method of regenerated cellulose nanofiltration membrane |
| CN106474944A (en) * | 2016-11-08 | 2017-03-08 | 福建农林大学 | A kind of preparation method of antibacterial cellulose flat board NF membrane |
| CN111437740A (en) * | 2020-03-09 | 2020-07-24 | 哈尔滨工业大学 | A kind of preparation method based on sodium lignosulfonate high-flux and high-cutoff nanofiltration membrane |
| CN112538777A (en) * | 2020-12-07 | 2021-03-23 | 广东省东莞市质量监督检测中心 | Regenerated cellulose film coated green food packaging paper and preparation method and application thereof |
| CN115025630A (en) * | 2021-06-02 | 2022-09-09 | 赛普(杭州)过滤科技有限公司 | Preparation method and product of hollow cellulose virus removal filtering membrane |
| CN115041024A (en) * | 2021-06-02 | 2022-09-13 | 赛普(杭州)过滤科技有限公司 | Preparation method of asymmetric regenerated cellulose virus-removing flat filter membrane and product |
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| CN106474944B (en) * | 2016-11-08 | 2019-04-23 | 福建农林大学 | A kind of preparation method of antibacterial cellulose flat nanofiltration membrane |
| CN111437740A (en) * | 2020-03-09 | 2020-07-24 | 哈尔滨工业大学 | A kind of preparation method based on sodium lignosulfonate high-flux and high-cutoff nanofiltration membrane |
| CN111437740B (en) * | 2020-03-09 | 2022-07-01 | 哈尔滨工业大学 | Preparation method of sodium lignosulfonate-based high-flux high-interception nanofiltration membrane |
| CN112538777A (en) * | 2020-12-07 | 2021-03-23 | 广东省东莞市质量监督检测中心 | Regenerated cellulose film coated green food packaging paper and preparation method and application thereof |
| CN112538777B (en) * | 2020-12-07 | 2023-05-16 | 广东省东莞市质量监督检测中心 | Regenerated cellulose film coated green food packaging paper and preparation method and application thereof |
| CN115025630A (en) * | 2021-06-02 | 2022-09-09 | 赛普(杭州)过滤科技有限公司 | Preparation method and product of hollow cellulose virus removal filtering membrane |
| CN115041024A (en) * | 2021-06-02 | 2022-09-13 | 赛普(杭州)过滤科技有限公司 | Preparation method of asymmetric regenerated cellulose virus-removing flat filter membrane and product |
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