DESC:SUPERPARAMAGNETIC NANOPARTICLE MEDIATED WATER REMEDIATION
FIELD OF INVENTION
The invention generally relates to the field of nanotechnology and particularly to superparamagnetic iron oxide nanoparticles mediated water remediation.
BACKGROUND
Dyes, including both natural and synthetic forms, are used in various industries. Examples of industries include but are not limited to paper, textile, leather, and plastic industries. Recent growth of these industries and presence of dyes in their waste effluents has created a major concern due to related environmental hazards.
Several methods have been used for removal of dye from wastewater. Examples of methods include but are not limited to photocatalytic degradation, sonochemical degradation, micellar enhanced ultrafiltration, cation exchange membranes, electrochemical degradation, adsorption/precipitation processes.
In the recent trend, techniques such as photocatalysis and dye adsorption using nanoparticles have been considered as effective methods for dye removal and effluent water remediation. Use of functionalized nanoparticles helps in efficient adsorption of the dye molecules due to the high surface-volume ratio and surface charge. However, these separation techniques are problematic and tedious involving time consuming and non-scalable steps.
Even though there are several reports on the efficiency of the nanomaterials for dye removal, there exists a gap for real-time dye removal process for a large quantity of wastewater.
BRIEF DESCRIPTION OF DRAWINGS
So that the manner in which the recited features of the invention can be understood in detail, some of the embodiments are illustrated in the appended drawings. It is to be noted, however, that the appended drawings illustrate only typical embodiments of this invention and are therefore not to be considered limiting of its scope, for the invention may admit to other equally effective embodiments.
FIG.1 shows a device for water remediation, according to an embodiment of the invention.
FIG.2 shows flowchart of the method for water remediation, according to an embodiment of the invention
FIG.3 shows schematic representation of process of electrospinning, according to an embodiment of the invention.
SUMMARY OF THE INVENTION
One aspect of the invention provides a water remediation device for effluent water treatment. The water remediation device comprises a hollow cylindrical body having a broad end (1) for letting in effluent water, a narrow end (2) connected to a nozzle for outlet of the treated water and a nanofiber matrix embedded with surfactant coated superparamagnetic iron oxide nanoparticles for treating the effluent water. The nanofiber matrix is contained within the hollow cylindrical body.

DETAILED DESCRIPTION OF THE INVENTION
Various embodiments of the invention providea water remediation device for effluent water treatment.Fig. 1 shows the device for effluent water treatment. The water remediation device comprises a hollow cylindrical body having a broad end (1) for letting in effluent water, a narrow end (2) connected to a nozzle for outlet of the treated water and a nanofiber matrix embedded with surfactant coated superparamagnetic iron oxide nanoparticles for treating the effluent water. Thenanofiber matrix is contained within the hollow cylindrical body. Superparamagnetic iron oxide nanoparticles are effective absorbers of the dye molecules present in effluent water and binds instantly due to the high surface-volume ratio and surface charge. They are highly suitable for separation of dye molecules from water medium. Superparamagnetic iron oxide nanoparticles have high magnetization values and exhibit great magnetic force even for a small magnetic field.
In one embodiment of the invention, the length of the device is in the range of about 60mm to 120mm. In another embodiment of the invention, the diameter of the device is in the range of 60mm to 120mm. In one example of the invention, the diameter is 15mm and length is 120mm.
In yet another embodiment of the invention, the narrow end and broad end of the device are provided with a retaining means (3) for restraining the nanofiber matrix within the cylindrical body. In one example of the invention, the retaining means is a threaded cap. In another example of the invention, the area of the square mesh in the threaded cap is in the range of about 314 mm2 to about 707 mm2. In yet another example of the invention, the area of the square mesh is 707 mm2.The device is directly introduced into the effluent water. The device is configured for controlled release of surfactant coated superparamagnetic iron oxide nanoparticles
Whenever the device is immersed in effluent water and after the reaction, the treated supernatant is pumped out using motor without affecting the sediment dye substance.The narrow end (2) connected to a nozzle is for removing the supernatant. A permanent magnet with field strength in the range of about 0.3 T to about 0.5 T is used for magnetic separation of coagulated dye substance. In one example of the invention, magnetic field strength of 0.5 Tis used for magnetic separation of coagulated dye substance with iron oxide nanoparticles.
According to an embodiment of the invention, time taken for water remediation is about 5 minutes to about 15 minutes. In one example of the invention, time taken for water remediationis about 15 minutes.
Fig.2 shows a flowchart of the method for water remediation, according to an embodiment of the invention. The method includes synthesis of nanoparticles embedded nanofibre (101), preparation of iron oxide nanoparticles embedded matrix (103), incorporation of nanoparticles embedded matrix into a device (105).The device is then placed into the effluent water for dye removal (107).
Superparamagnetic iron oxide Nanoparticles are synthesized using coprecipitation technique. Coprecipitation involves reaction between Iron(III) chloride hexahydrate (FeCl3• 6H2O, 97%), Iron(II) Chloride Tetrahydrate (FeCl2•4H2O, 99%) with ammonia solution, at a temperature in the range of about 25ºC to about 30º C and air atmospheric conditions in the range of about 90kPa to about 180kPa. In one example of the invention, the reaction is carried out at a temperature of 27º C and a pressure of 101.3 kPa. Molar ratio of Fe2+: Fe3+ plays important role in tuning the composition, particle size and magnetization of the material. Molar ratio of Fe2+: Fe3+ used in the invention is in the range of about 1:3to about 3:1. In one example of the invention 1:3 molar ratio of Fe2+: Fe3+ is taken. Ammonia solution 25% in a range of about 20mL to about 25mL is added drop-wise to a mixture of Iron salts in aqueous medium. In one example of the invention, 25 mL of diluted ammonia solution is added to the precursor. The reaction is continued under mechanical stirring for about 20 minutes, change in solution color during reaction indicates the formation of iron oxide nanoparticles. The nanoparticles are washed with ethanol and water followed by magnetic decantation process. The synthesized nanoparticles are maintained in precipitate form and Tetramethylammonium hydroxide surfactant in the range of about 10 µl to 20 µl is added drop-wise to the precipitate and is allowed to mix for about 20 minutes using a mechanical stirrer. In one example of the invention 20 µl of Tetramethylammonium hydroxide (TMAH) is used as a peptizer in the reaction TMAH stabilized nanoparticles hence prepared, is used for further procedures.
The iron oxide nanoparticles are then characterized, through known characterization techniques.The particle size of the nanoparticles is in the range about 4 nm to about 20 nm, and saturation magnetization in the range about 50 emu/g to about 75 emu/g. In one example of the invention, the particle size of iron oxide nanoparticle is about 4 to about 11 nm and Saturation magnetization is 58 emu/g. Subsequent to characterization, iron oxide nanoparticles embedded nanofibre matrix is prepared through electrospinning method. Matrixes described herein include but are not limited to nylon, carbon fiber.
Iron oxide nanoparticles in the range of about 10µl to about 20µl are dispersed in about 2ml of Milli-Q water. In one example, 20µl of Iron oxide nanoparticles are dispersed in Milli-Q water. Polyvinyl alcohol (PVA) powder is added gradually into the solution. Polyvinyl alcohol (PVA) powder 12% is used in the range of about 0.5g to 0.6g. In one example of the present invention, 0.6g amount of PVA powder is used. PVA is dissolved under mechanical stirring for about 60 minutes at a temperature range of about 500C to about 600C. In one example of the invention, PVA is dissolved through stirring process at 600C of temperature. The stirring process is continued until the solution becomes viscous. Obtained PVA solution with Iron oxide nanoparticles is further stirred for about 30 minutes to 40 minutes at temperature range of about 500Cto about 600C for proper dispersion of nanoparticles. In one example of the invention, the solution is stirred at a temperature of 60º C for about 40 minutes.The whole solution is then electrospun to obtain nanofiber under applied voltage in the range of about 12kV to about 15kV, with the flow rate in the range of about 0.3 ml/hour to about 0.5 ml/hour. In one example of the invention, electrospinning is done at 12kv of applied voltage and flow rate is maintained at 0.3 ml/hr. Electrospinning is performed using two types of set-up, one of the setup is static sheet and the other is rotating drum. Schematic representation of both the processes of electrospinning is shown in Fig.3. In static sheet setup, the nanofibers are collected over a flexible nylon matrix attached over analuminium foil static sheet collector, whereas for rotating drum setup, nanofibers are collected over nylon matrix, which is fixed to an aluminium foil over rotating drum collector. Dimension of the nylon matrix in the present invention is in the range of about 80x20 mm2 to about 60x40 mm2 and pore size is of about1x1 mm2to about 5x5 mm2. In one example of the invention, dimension of nylon matrix is 60x40 mm2 and the pore size is1x1 mm2. For rotating drum setup, the fibers are placed over the rotating drum collector; the collector drum speed is maintained at about 1400 RPM to about 1500 RPM. This process is undertaken to optimize the deposition of nanofiber over the required area in the matrix. Nanoparticles embedded matrix, according to the present invention, releases nanoparticles in a controlled manner. It also acts as a protective layer for nanofiber allowing the effluent water to pass though it without damaging the nanofiber.
According to an embodiment of the invention, pore size of the nanofibre matrix is of about 1x1 mm2 to about 5x5 mm2. In one example of the present invention, pore size is 1x1 mm2. Pore number of the nanofibre matrix is about 1674 to about 2080. In one example of the invention about 1674 number of pores is present on the nylon matrix.
In one embodiment of the invention, the device is configured for controlled release of superparamagnetic iron oxide nanoparticles. Matrix allows the nanofiber to react only with the sample. Matrix inside the device can withstand flow condition.The device can also be used in other fields such as, agriculture and medical for controlled release of nanoparticles or drugs to target medium. Separation of dye from larger quantity of waste water is possible.
The foregoing description of the invention has been set merely to illustrate the invention and is not intended to be limiting. Since modifications of the disclosed embodiments incorporating the spirit and substance of the invention may occur to person skilled in the art, the invention should be construed to include everything within the scope of the appended claims and equivalents thereof.
,CLAIMS:We Claim,
1. A water remediation device for effluent water treatment, comprising a hollow cylindrical body having a broad end (1) for letting in effluent water, a narrow end (2) connected to a nozzle for outlet of the treated water and a nanofiber matrix embedded with surfactant coated superparamagnetic iron oxide nanoparticles for treating the effluent water, wherein the nanofiber matrix is contained within the hollow cylindrical body.
2. The device as claimed in claim 1, wherein the narrow end (2) and the broad end (1) are provided with a retaining means (3) for restraining the nanofiber matrix within the cylindrical body.
3. The device as claimed in claim 1, wherein the time taken for water remediation is in the range of 5 minutes to 15 minutes.
4. The device as claimed in claim 1, wherein the dimension of the nanofiber matrix is in the range of 60*40 mm2 to 80*20 mm2.
5. The device as claimed in claim 1, wherein the particle size of superparamagnetic iron oxide nanoparticles in the range of 4 nm to 20 nm.
6. The device as claimed in claim 1, wherein the pore size of the nanofiber matrix is in the range of 1*1 mm2 to 5*5 mm2.
7. The device as claimed in claim 1, wherein the length of the device is in the range of 60mm to 120mm.
8. The device as claimed in claim 1, wherein the diameter of the device is in the range of 60mm to 120mm.
9. The device as claimed in claim 1, wherein the surfactant is Tetramethyl ammonium hydroxide.
10. The device as claimed in claim 1, wherein thedevice is configured for controlled release of superparamagnetic iron oxide nanoparticles.