CN109092083A - A kind of preparation and application of ferroso-ferric oxide/regenerated cellulose magnetism forward osmosis membrane - Google Patents
A kind of preparation and application of ferroso-ferric oxide/regenerated cellulose magnetism forward osmosis membrane Download PDFInfo
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- CN109092083A CN109092083A CN201710469554.XA CN201710469554A CN109092083A CN 109092083 A CN109092083 A CN 109092083A CN 201710469554 A CN201710469554 A CN 201710469554A CN 109092083 A CN109092083 A CN 109092083A
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Abstract
The invention discloses a kind of Fe3O4/ regenerated cellulose magnetism forward osmosis membrane and its preparation and application.First pass through coprecipitation preparation magnetic Fe3O4Then solid is mixed with cellulose solution, composite solution is made, composite solution is through knifing, solidification, immersion and is dried in vacuo obtained Fe3O4/ regenerated cellulose forward osmosis membrane.Fenton-like catalytic degradation is coupled by the permeable membrane with membrane separating process, can carry out the removal of pollutant and the minimizing processing of waste water simultaneously, is a kind of completely new pollutant process method.
Description
Technical field
The invention belongs to the preparation fields of membrane material, and in particular to a kind of Fe3O4/ regenerated cellulose magnetism forward osmosis membrane and
It is prepared and application.
Background technique
With the development of DYE PRODUCTION and dyeing, the discharge amount of dying industrial wastewater sharply increases.And dyestuff is useless
Water constituent is complicated, contains a variety of refractory organics, is one of industrial wastewater difficult to deal in water treatment field.Printing and dyeing are useless
Water contains a large amount of organic pollutant, and dissolved oxygen will be consumed by being discharged into water body, breaks meeting Ecology balance, jeopardizes fish and other aquatic lifes
The existence of object.As China is for the attention of environmental protection, the discharge standard of industrial wastewater is continuously improved, sewage treatment means
It is also imperative to update.
Common dye wastewater treatment means include bioanalysis, physisorphtion, Fenton oxidation method, electrochemical process, film
Partition method etc., wherein bioanalysis need can Biological Pretreatment, and limited by dyes；Physisorphtion can not destroy dyestuff
The structure of molecule, adsorbent reactivation is difficult or regeneration cost is higher；There are excessive Fes for Fenton oxidation method2+Cause secondary pollution
Problem；Electrochemical process has the problems such as energy consumption is high, processing cost is high；Membrane separation process mainly uses ultrafiltration and nanofiltration to handle dye
Expect waste water, concentration polarization and fouling membrane phenomenon easily occurs.
The present invention is with Fe3O4/ regenerated cellulose magnetism forward osmosis membrane is as modified Fenton reaction, Fe3O4It is embedded in regeneration
In cellulose fenestra, during methylene blue catalytic degradation, Fe2+Fenton reaction is slowly generated and sufficiently participated in, is not easy to make
At excess；On the other hand, which carries out UF membrane to waste water from dyestuff using positive infiltration technology, has low energy consumption, separation effect
Fruit is good and the features such as low fouling membrane.The present invention organically combines Fenton-like catalysis technique and positive infiltration technology, not only to routine
Fenton oxidation method and membrane separation process improved, while using the coupling of two kinds of processing techniques, it is useless to improve dyestuff
The treatment effect of water.
Summary of the invention
In view of the above-mentioned deficiencies in the prior art, it is an object of the present invention to provide a kind of Fe3O4The magnetic positive infiltration of/regenerated cellulose
Film and its preparation and application.Fenton-like catalytic degradation is coupled by the forward osmosis membrane with membrane separating process, can simultaneously into
The removal of row pollutant and the minimizing processing of waste water, are a kind of completely new pollutant process methods.
In order to realize goal of the invention, the present invention adopts the following technical scheme:
A kind of Fe3O4The preparation method of/regenerated cellulose magnetism forward osmosis membrane: by magnetic Fe3O4Solid abrasive is at powder, with 2wt%-
The mixing of 8wt% cellulose solution is sufficiently stirred simultaneously 5 ~ 30min of ultrasonic vibration, obtains the uniform magnetic Fe of black3O4/ cellulose is multiple
Close solution；By magnetic Fe3O4/ cellulose composite solution is by knifing, solidification, immersion and is dried in vacuo obtained magnetic Fe3O4/ again
Raw cellulose forward osmosis membrane.
The magnetic Fe3O4Solid the preparation method comprises the following steps: taking 90 ml, 0.3 mol/L FeCl respectively3Solution and 51 ml
0.3 mol/L FeCl2Solution is passed through nitrogen into four-hole boiling flask into 250 ml four-hole boiling flasks, in a nitrogen atmosphere ultrasound shake
Swing 30 min, after keep nitrogen atmosphere, move into thermostat water bath, quickly stirred using electric mixer；To solution temperature
When rising to 60 DEG C, it is rapidly added 40 ml, 14 wt % ammonium hydroxide；Then when reaction temperature rises to 80 DEG C, 2.5 h of isothermal reaction；
After the reaction was completed, in a nitrogen atmosphere, solution is cooled to room temperature, and obtains dark solution and with magnet adsorbing separation, ethyl alcohol cleaning,
Under the conditions of 30 DEG C, vacuum drying obtains black magnetic Fe3O4Solid.
The magnetic Fe3O4In/cellulose composite solution, magnetic Fe3O4Mass fraction be 2%-8%.
Knifing, solidification, immersion and the vacuum drying specifically: by magnetic Fe3O4/ cellulose composite solution is poured on glass
In glass plate, hymenotome is scraped with 100-300 μm solution is evenly laid out on a glass, glass plate is placed in 30 ~ 60 DEG C of baking ovens and is dried
Dry 30 ~ 90min, is transferred in solidification liquid, impregnates 5 ~ 20 min, obtains regenerated cellulose wet film, after clear water impregnates, 30 ~
Magnetic Fe is made in 60 DEG C of 12 ~ 36h of vacuum drying3O4/ regenerated cellulose forward osmosis membrane.
The solidification liquid is 10wt% ethanol water, 5wt%H3PO4-5wt%Na2HPO4Solution or 5wt%Na2SO4-
5wt%H2SO4One of solution.
Fe made from a kind of preparation method as described above3O4/ regenerated cellulose magnetism forward osmosis membrane is in catalytic degradation methylene
Application in base indigo plant waste water from dyestuff.
Forward osmosis membrane can be used for handling in positive permeability apparatus methylene blue dye wastewater, and the side of film is useless with methylene blue
Water can carry out Fenton-like catalytic degradation reaction as material liquid, remove methylene blue pollutant；Made with salt water the other side of film
To draw liquid, realize that water is reduced from material liquid using film two sides permeable pressure head.
Forward osmosis membrane can be used for handling in positive permeability apparatus methylene blue dye wastewater, and the material liquid side of film is because of class
Fenton catalytic degradation reaction reduces pollutant concentration, and two sides permeable pressure head increases, and promotes water from material liquid side to drawing liquid
The flux of side；Meanwhile as the decrement of water in material liquid side, pollutant concentration increase, promote the catalytic degradation reaction of pollutant.
The beneficial effects of the present invention are:
The present invention couples Fenton-like catalytic degradation with membrane separating process, obtained Fe3O4The magnetic positive infiltration of/regenerated cellulose
Permeable membrane can carry out the removal of pollutant and the minimizing processing of waste water simultaneously, be a kind of novel pollutant process method.
Detailed description of the invention
The XRD spectrum of the various membrane materials of Fig. 1；
The scanning electron microscope (SEM) photograph of Fig. 2 forward osmosis membrane material.
Specific embodiment
The present invention is further illustrated by the following examples, but protection scope of the present invention is not limited to following reality
Apply example.
Embodiment 1
A kind of Fe3O4The preparation of/regenerated cellulose magnetism forward osmosis membrane, specific steps are as follows:
1) magnetic Fe3O4The preparation of solid: 90 ml, 0.3 mol/L FeCl is taken respectively30.3 mol/L of solution and 51 ml
FeCl2Solution is passed through nitrogen into four-hole boiling flask into 250 ml four-hole boiling flasks, in a nitrogen atmosphere 30 min of ultrasonic vibration,
After keep nitrogen atmosphere, move into thermostat water bath, quickly stirred using electric mixer；60 DEG C are risen to solution temperature
When, it is rapidly added 40 ml, 14 wt% ammonium hydroxide；Then when reaction temperature rises to 80 DEG C, 2.5 h of isothermal reaction；Reaction is completed
Afterwards, in a nitrogen atmosphere, solution is cooled to room temperature, and obtains dark solution and with magnet adsorbing separation, ethyl alcohol cleaning, in 30 DEG C of items
Under part, vacuum drying obtains black magnetic Fe3O4Solid；
2) Fe3O4The preparation of/regenerated cellulose magnetism forward osmosis membrane: by 50mg magnetic Fe3O4Solid abrasive is at powder, with 5ml
The mixing of 4wt% cellulose solution is sufficiently stirred simultaneously 10 min of ultrasonic vibration, obtains the uniform magnetic Fe of black3O4/ cellulose is compound
Solution；By magnetic Fe3O4/ cellulose composite solution scrapes hymenotome on a glass, with 300 μm, and solution is evenly laid out in glass
On plate, it is placed on 50min in 40 DEG C of baking ovens, glass plate is transferred in 10wt% ethanol solution, impregnate 10 min, it is fine to obtain regeneration
Plain wet film is tieed up, after clear water repeatedly impregnates, in 40 DEG C of vacuum drying 20h, magnetic Fe is made3O4/ regenerated cellulose forward osmosis membrane
(it is calculated as Fe3O4/ RC film).
Embodiment 2
A kind of preparation of regenerated cellulose film: preparing 4 wt% cellulose solutions, and 1.0 g alpha-celluloses and 50 ml diformazans are added
Yl acetamide is stirred at reflux 2 h under the conditions of 130 DEG C；Stop heating and naturally cool to 100 DEG C, the anhydrous chlorination of 3 g is added
Lithium is stirred at reflux, and is cooled to room temperature, and transparent, sticky cellulose solution is obtained；6 ml cellulose solutions are taken, glass plate is poured on
On, hymenotome is scraped with 300 μm solution is evenly laid out on a glass, then placed in refrigerator, freeze 10 min or more, so that
Cellulose solution freezes.Glass plate is transferred in 10wt% ethanol solution, 10 min are impregnated, obtains regenerated cellulose wet film, warp
After clear water repeatedly impregnates, under the conditions of 60 DEG C, regenerated cellulose film is made in vacuum drying, is labeled as RC film.
Application Example 1
Forward osmosis membrane is placed in membrane separation device, with pH=3,10mg/L methylene blue (MB) solution is material liquid, 2mol/
LNaCl solution is to draw liquid, and H is added in methylene blue solution2O2, H2O2Concentration is 0.1mol/L, material liquid and draws flow velocity
Identical, temperature is room temperature.Using ultraviolet spectrogram ultraviolet specrophotometer measurement material liquid and draw liquid, with Atomic absorption point
The salinity of light photometric determination material liquid.
Degradation rate (%), water flux (L/m2And flux salt (mol/m h)2H) following formula expression is respectively adopted:
In formula,c MB,0For the initial concentration for preceding material liquid Methylene Blue of degrading, mg/L；c MB,tFor methylene in material liquid after degradation
The residual concentration of base indigo plant, mg/L；V t It is material liquid in the volume after degradation-UF membrane, L；V 0 It is the first initial body of material liquid
Product, L；ΔVDraw increased water volume, L in liquid；AFor the effective area of film, m2；ΔtFor degradation-UF membrane time, h；c s,0
For the initial concentration of salt in preceding material liquid of degrading, mol/L；c s,tFor the salinity of material liquid after degradation, mol/L；
Respectively to regenerated cellulose film and Fe3O4/ regenerated cellulose film carries out catalytic degradation performance and the test of positive permeance property, and
It investigates while progress or the influence without positive process of osmosis to catalytic degradation effect, processing of the waste water through 2h is as a result as follows:
Influence of the positive process of osmosis of table 1 to catalytic degradation
Respectively to regenerated cellulose film and Fe3O4/ regenerated cellulose film carry out membrane separating property test, and investigate simultaneously progress or
Influence without catalytic degradation process to the positive permeance property of film, processing of the waste water through 2h are as a result as follows:
Influence of the 2 catalytic degradation process of table to the positive permeance property of film
In conclusion the present invention couples Fenton-like catalytic degradation with membrane separating process, obtained Fe3O4/ regenerated fiber
Biscuit porcelain forward osmosis membrane can carry out the removal of methylene blue Pollutants in Wastewater and the minimizing processing of waste water, technical effect simultaneously
It is prominent.
The foregoing is merely presently preferred embodiments of the present invention, all equivalent changes done according to scope of the present invention patent with
Modification, is all covered by the present invention.
Claims (8)
1. a kind of Fe3O4The preparation method of/regenerated cellulose magnetism forward osmosis membrane, it is characterised in that: by magnetic Fe3O4Solid abrasive
Cheng Fen is mixed with 2wt% ~ 8wt% cellulose solution, and simultaneously 5 ~ 30min of ultrasonic vibration is sufficiently stirred, obtains the uniform magnetism of black
Fe3O4/ cellulose composite solution；By magnetic Fe3O4/ cellulose composite solution passes through knifing, solidification, immersion and vacuum drying system
Obtain magnetic Fe3O4/ regenerated cellulose forward osmosis membrane.
2. Fe according to claim 13O4The preparation method of/regenerated cellulose magnetism forward osmosis membrane, it is characterised in that: institute
The magnetic Fe stated3O4Solid the preparation method comprises the following steps: taking 90 ml, 0.3 mol/L FeCl respectively30.3 mol/L of solution and 51 ml
FeCl2Solution is passed through nitrogen into four-hole boiling flask into 250 ml four-hole boiling flasks, in a nitrogen atmosphere 30 min of ultrasonic vibration,
After keep nitrogen atmosphere, move into thermostat water bath, quickly stirred using electric mixer；60 DEG C are risen to solution temperature
When, it is rapidly added 40 ml, 14 wt % ammonium hydroxide；Then when reaction temperature rises to 80 DEG C, 2.5 h of isothermal reaction；Reaction is completed
Afterwards, in a nitrogen atmosphere, solution is cooled to room temperature, and obtains dark solution and with magnet adsorbing separation, ethyl alcohol cleaning, in 30 DEG C of items
Under part, vacuum drying obtains black magnetic Fe3O4Solid.
3. Fe according to claim 13O4The preparation method of/regenerated cellulose magnetism forward osmosis membrane, it is characterised in that: institute
The magnetic Fe stated3O4In/cellulose composite solution, magnetic Fe3O4Mass fraction be 2%-8%.
4. Fe according to claim 13O4The preparation method of/regenerated cellulose magnetism forward osmosis membrane, it is characterised in that: institute
Knifing, solidification, immersion and the vacuum drying stated specifically: by magnetic Fe3O4/ cellulose composite solution on a glass, is used
100-300 μm to scrape hymenotome evenly laid out on a glass by solution, by glass plate be placed on drying 30 in 30 ~ 60 DEG C of baking ovens ~
90min is transferred in solidification liquid, impregnates 5 ~ 20 min, obtains regenerated cellulose wet film, true at 30 ~ 60 DEG C after clear water impregnates
Dry 12 ~ the 36h of sky, is made magnetic Fe3O4/ regenerated cellulose forward osmosis membrane.
5. Fe according to claim 43O4The preparation method of/regenerated cellulose magnetism forward osmosis membrane, it is characterised in that: institute
The solidification liquid stated is 10wt% ethanol water, 5wt%H3PO4-5wt%Na2HPO4Solution or 5wt%Na2SO4-5wt%H2SO4Solution
One of.
6. Fe made from a kind of preparation method as described in any one in claim 1-53O4/ regenerated cellulose magnetism forward osmosis membrane.
7. Fe according to claim 63O4/ regenerated cellulose magnetism forward osmosis membrane is useless in catalytic degradation methylene blue dye
Application in water.
8. Fe according to claim 73O4/ regenerated cellulose magnetism forward osmosis membrane is useless in catalytic degradation methylene blue dye
Application in water, it is characterised in that: Fe3O4The side of/regenerated cellulose magnetism forward osmosis membrane addition H2O2Methylene blue dye
Waste water is expected as material liquid, and the other side uses salt water as drawing liquid.
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Cited By (5)
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| CN110204031A (en) * | 2019-06-05 | 2019-09-06 | 长春理工大学 | The integrated apparatus and its application method of light Fenton-just infiltration Combined Treatment bio-refractory organic wastewater |
| CN111715289A (en) * | 2020-05-09 | 2020-09-29 | 广西大学 | In-situ synthesis of FeOOH/Fe3O4Method for preparing/cellulose composite material and application thereof |
| CN113289506A (en) * | 2021-06-15 | 2021-08-24 | 江南大学 | Asymmetric magnetic oxygen-nitrogen separation membrane and preparation method thereof |
| CN113731185A (en) * | 2021-04-19 | 2021-12-03 | 保定源汉升新材料科技有限公司 | Composite film for removing liquid-phase refractory organic pollutants and synthesis method thereof |
| CN115532312A (en) * | 2022-10-10 | 2022-12-30 | 中国民航大学 | Preparation method of biomass cellulose composite magnetic iron oxide nano catalyst |
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Cited By (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110204031A (en) * | 2019-06-05 | 2019-09-06 | 长春理工大学 | The integrated apparatus and its application method of light Fenton-just infiltration Combined Treatment bio-refractory organic wastewater |
| CN111715289A (en) * | 2020-05-09 | 2020-09-29 | 广西大学 | In-situ synthesis of FeOOH/Fe3O4Method for preparing/cellulose composite material and application thereof |
| CN111715289B (en) * | 2020-05-09 | 2023-03-14 | 广西大学 | In-situ synthesis of FeOOH/Fe 3 O 4 Method for preparing/cellulose composite material and application thereof |
| CN113731185A (en) * | 2021-04-19 | 2021-12-03 | 保定源汉升新材料科技有限公司 | Composite film for removing liquid-phase refractory organic pollutants and synthesis method thereof |
| CN113731185B (en) * | 2021-04-19 | 2023-09-19 | 保定源汉升新材料科技有限公司 | Composite film for removing liquid-phase refractory organic pollutants and synthesis method thereof |
| CN113289506A (en) * | 2021-06-15 | 2021-08-24 | 江南大学 | Asymmetric magnetic oxygen-nitrogen separation membrane and preparation method thereof |
| CN113289506B (en) * | 2021-06-15 | 2023-02-28 | 江南大学 | Asymmetric magnetic oxygen-nitrogen separation membrane and preparation method thereof |
| CN115532312A (en) * | 2022-10-10 | 2022-12-30 | 中国民航大学 | Preparation method of biomass cellulose composite magnetic iron oxide nano catalyst |
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