Method for producing polystyrene microparticles or microfibers from waste polystyrene using spinning disk equipment

Abstract

The invention discloses a method (200) for reclaiming polystyrene microparticles or microfibers from waste expanded polystyrene using a customized spinning disc apparatus (300). The method(200) includes dissolving (202) predetermined amount of polystyrene waste in tetrahydrofuran (THF) and filtering (203) to remove solid impurities to get a first feed liquid. The first feed liquid is then diluted with THF to get a diluted feed liquid and introduced into the spinning disc apparatus to produce micro-droplets (208) leading to microparticles having narrow size distribution. For producing microfibers, concentrated feed fluid is used to generate fluid ligaments (207), which result in microfibers having narrow range of diameters as well as with nanoporous surface. The method converts waste into valuable particles for various applications including biomedical, imaging, colloidal fluids. The polystyrene microfibers are useful as oil adsorbant.

Description

METHOD FOR PRODUCING POLYSTYRENE MICROPARTICLES OR MICROFIBERS FROM WASTE POLYSTYRENE USING SPINNING DISK EQUIPMENTCROSS-REFERENCES TO RELATED APPLICATIONS

[0001] This application claims priority to Indian Patent Application No. 202341055003 entitled METHOD FOR PRODUCING POLYSTYRENE MICROPARTICLES OR MICROFIBERS FROM WASTE POLYSTYRENE USING SPINNING DISK EQUIPMENT filed on 16 August 2024.FIELD OF THE INVENTION

[0002] The present disclosure relates to reclaiming waste expanded polystyrene to produce polystyrene microparticles and microfibers.BACKGROUND OF THE RELATED ART

[0003] Expanded Polystyrene (EPS) is a non-toxic inert polymer which is used for versatile applications such as materials for packing, decoration purposes, manufacture of cups and trays and so on, due to its fascinating features of low cost, light weight, corrosion-resistance, and processability. Annually, it is estimated that 14.7 MMT of polystyrene is produced, among this 6.6 MMT is EPS. It is found that 6.63 tons / day of polystyrene waste in the form of waste expanded polystyrene (WPS) is produced around the world. WPS causes several environmental problems due to its non-biodegradability and demands considerable space due to its large volume to weight ratio. Hence disposing or recycling WPS is a challenge.

[0004] Most of the WPS is disposed of by landfill or by incineration. Landfill causes soil and water pollution and also increases disposal sites. Incineration is an energy recycling method, but incineration of polystyrene produces hazardous chemicals. There are several mechanical recycling methods, but these are more expensive than producing virgin polystyrene. Moreover, these methods are mainly aimed at eliminating polystyrene rather than converting it into a valuable product. Hence, recycling of WPS into a valuable product in an environmentally friendly as well as economical manner is highly necessary.

[0005] Conversion of WPS into valuable products like nano or microparticles and nano or microfibers is a possible way of recycling WPS as they can be used for several purposeslike biomedical applications, imaging, preparation of engineered colloid particles, oil adsorption and so on. Particularly, polystyrene microparticles can be used for lateral flow tests, latex agglutination tests, flow cytometry, fluorescence microscopy, and as calibration particles. Polystyrene microfibers with nanoporous structure are considered to be one of the best oil sorbents to absorb oil from the ocean in case of oil spill. Polystyrene fibers are also used as fiber membranes and as additives in the paint industry.

[0006] Conventional methods for bulk production of polystyrene microparticles such as spray drying, fluidized bed drying, electro-spraying and polymerization have limitations especially in the control over particle size distribution and surface morphology. Also, these methods require challenging operating conditions such as high gas flow rates, high temperature for drying, pressures greater than atmospheric conditions and so on. Microfluidic generation of droplets is one method by which highly monodisperse particles can be produced but there are a number of drawbacks concerning lower production rates, handling viscous and impure solutions, separation of particles from continuous phase, wetting issues and so on. Thus, a technique that can overcome all these aforementioned disadvantages and can generate droplets with narrow size distribution is required.

[0007] In case of polystyrene microfibers production, conventional techniques like electrospinning and centrifugal spinning have several disadvantages. Electrospinning does not have a higher production rate, requires a high voltage external power source and may not be able to handle all kinds of hydrocarbon solvents and viscous solutions. Centrifugal spinning, an emerging method, has several demerits such as lower production rate, handling viscous solutions and clogging issues. Hence, an alternative method is required for the production of microfibers that addresses the aforementioned demerits.

[0008] US2020102427A1 discusses a method for creating polystyrene microparticles utilizing microprecipitation, which incorporates agitation and a secondary solvent. EP3060704A1 uses a rotating disk or bowl to produce nanofibers from the polymer melts. Da-Wei Pan et al., 2023 reported a Facile and Scalable Rotation-Based Microfluidics for Controllable Production of Emulsions, Microparticles, and Microfibers, using rotationbased microfluidics.

[0009] The current state of art provides design which can be used for either production of polystyrene microparticles or for the production of polystyrene microfibers. There istherefore need for a single equipment which can be used for production of both polystyrene microparticles and micro fibers.SUMMARY OF THE INVENTION

[0010] In various embodiments, a method (200) for reclaiming polystyrene (PS) from waste expanded polystyrene in the form of microparticles or microfibers using a customized spinning disc apparatus (CSDA) (300) is disclosed. The method includes providing (201) a spinning disc apparatus (SDA)(100), dissolving (202) predetermined quantity waste polystyrene in tetrahydrofuran(THF), filtering (203) to remove solid impurities to get a first feed liquid, mixing (204) the first feed liquid and THF as a second feed liquid at controlled rates into a static mixer (315) to vary the concentration of the PS to THF to get a diluted feed liquid to produce microparticles, introducing the diluted feed liquid (206) or the first feed liquid (205) into the spinning disc apparatus (100), generating micro-droplets(208) (or) fluid ligaments(207) at a periphery of the rotating disc (4) and directing (210) the generated micro-droplets from the disc (4) to a precipitation chamber (14) to produce polystyrene microparticles(212) or solidifying (211) the generated fluid ligaments to produce(213) polystyrene microfibers.

[0011] In some embodiments, the step dissolving predetermined concentration of polystyrene in THF to get the first feed liquid comprises dissolving (202) 20-30g of polystyrene in 100 ml of THF.

[0012] In various embodiments, directing (209) the generated micro-droplets from the disc (4) to a precipitation chamber (14) having antisolvent to produce microparticles, comprising the steps of solidifying the microdroplets in the precipitation chamber (14), separating the particles collected in the precipitation chamber (14) from the antisolvent and drying the particles to obtain solid polystyrene micro-particles of predefined size (212).

[0013] In some embodiments, obtaining polystyrene microparticles of predefined size comprises adjusting one or more of: the concentration of the final feed liquid, the speed ofthe spinning disk, the flow rate of the first feed liquid and second feed liquid to achieve the required concentration and the location of the antisolvent tray at a predefined distance.

[0014] In some embodiments, obtaining polystyrene microparticles of predefined size comprises, mixing the first feed liquid at 3L / h-5L / h and second feed liquid at 9L / h-15L / h, thereby achieving 3-8g of polystyrene per 100 ml of THF.

[0015] In some embodiments, the size of the polystyrene micro-particles is obtained in the range 90-125 microns.

[0016] In some embodiments, obtaining polystyrene microparticles of predefined size comprises, maintaining speed of the spinning disc at 3000 -4000rpm.

[0017] In some embodiments, obtaining polystyrene microparticles of predefined size comprises, locating the antisolvent tray at a predefined distance of 45 to 55 cm from the center of the rotating disc (4).

[0018] In various embodiments, the step solidifying (209) the generated fluid ligaments into polystyrene microfibers, including the steps of: supplying (209) nitrogen at the periphery of the rotating disc, drying the generated fluid ligaments into microfibers (219) by the nitrogen and collecting the polystyrene microfibers (213)from the apparatus (300).

[0019] In various embodiments, obtaining predefined size of polystyrene microfibers comprises adjusting one or more of: the flow rate of first feed liquid, the speed of the spinning disk and the nitrogen flow rate.

[0020] In various embodiments, obtaining predefined size of polystyrene microfibers comprises introducing (205) the first feed liquid at controlled rate of 3L / h to 5L / h.

[0021] In various embodiments, obtaining predefined size of polystyrene microfibers comprises adjusting the speed of spinning disc in the range 3500-4000 rpm.

[0022] In various embodiments, obtaining predefined size of polystyrene microfibers comprises supplying (217) nitrogen at a flow rate of 9000L / h-10500L / h

[0023] In various embodiments, the polystyrene micro-fibers are produced with an average diameter of about 10±4 micrometer.

[0024] In various embodiments, the reclaiming polystyrene in the form of microfibers comprises feeding 22-25g of polystyrene in 100ml ofTHF. .

[0025] This and other aspects are described herein.BRIEF DESCRIPTION OF THE DRAWINGS

[0026] The invention has other advantages and features which will be more readily apparent from the following detailed description of the invention and the appended claims, when taken in conjunction with the accompanying drawings, in which:

[0027] FIG. 1A illustrates Schematic representation of CSDA with feed line I and feed line II.

[0028] FIG. IB illustrates Schematic layout of spinning disc apparatus (SDA).

[0029] FIG. 1C illustrates a perspective view of the spinning disc apparatus (SDA).

[0030] FIG.2 illustrates method for reclaiming PS micro particles / PS microfibers from WPS.

[0031] FIG.3A and 3B illustrate SEM images of polystyrene micro particles.

[0032] FIG.4 illustrates SEM images of polystyrene microfibers.

[0033] FIG.5 A is a graph showing the variation of average particle size with distance from the centre of the rotating disc.

[0034] FIG.5B is a graph showing particle size distribution curve.

[0035] FIG.6 is a graph showing size distribution of fibers.

[0036] Referring to the figures, like numbers indicate like parts throughout the various views.DETAILED DESCRIPTION OF THE EMBODIMENTS

[0037] While the invention has been disclosed with reference to certain embodiments, it will be understood by those skilled in the art that various changes may be made and equivalents may be substituted without departing from the scope of the invention. In addition, many modifications may be made to adapt to a particular situation or material to the teachings of the invention without departing from its scope.

[0038] Throughout the specification and claims, the following terms take the meanings explicitly associated herein unless the context clearly dictates otherwise. The meaning of "a", "an", and "the" include plural references. The meaning of "in" includes "in" and "on."Referring to the drawings, like numbers indicate like parts throughout the views. Additionally, a reference to the singular includes a reference to the plural unless otherwise stated or inconsistent with the disclosure herein.

[0039] The present subject matter describes a method for reclaiming polystyrene (PS) from waste expanded polystyrene (WPS) in the form of microparticles or microfibers using a customized spinning disc apparatus (CSDA). The CSDA have a spinning disc apparatus (SDA) with a first feed line containing a highly concentrated first feed liquid and a second feed line containing a second feed liquid, the method includes dissolving predetermined amount of polystyrene in THF to get the first feed liquid, filtering the feed liquids, connecting the first feed line and second feed line with SDA to produce polystyrene microparticles or only the first feed line with the SDA to produce polystyrene microfibers, by varying the flow rates of the feed liquid in fist feed line and second feed line to get a final feed liquid with predefined concentration of polystyrene can be achieved, which is fed into a rotating disc of the SDA to produce polystyrene microparticles or microfibers thereby.

[0040] In various embodiments, a customized spinning disc apparatus (CSDA) 300 is disclosed for preparing a polystyrene (PS) microparticles or microfibers, as illustrated with reference to FIG. 1A-1C. As shown in FIG. 1A, the apparatus 300 comprises a spinning disc atomization apparatus 100 with a first feed line I and a second feed line II, the first feed line I and second feed line II comprises a feed vessels 311a, 311b configured to store first feed liquid and second feed liquid, the feed vessels are connected to a flow meter 313a, 313b to calibrate the flow rate of first feed liquid and second feed liquid, plurality of filters 312a, 312b are positioned both upstream and downstream of the flow meter, configured to remove any solid impurities present within the feed solution, a plurality of vent lines (not shown) are provided at the outlet of the flow meter which removes the trapped air and ensures that no air bubble is attached to the float of the flowmeter 313a, 313b which can affect the indicated flow, an isolation value 314a, 314b and a static mixer 315 are provided on the feed line to restrict and control the fluid flow and to vary the concentration of the first feed liquid and the second feed liquid as per the requirement, a gas distributor 316 is provided on the feed line to supplies nitrogen uniformly and a feed nozzle 48 is provided at an end of the flow line to introduce the feed liquid.

[0041] In various embodiments, the spinning disc atomization apparatus 100 is disclosed with reference to patent application IN 202241058428. As shown in FIG. IB and 1C, the spinning disc atomization apparatus 100 comprises a liquid collection drum assembly configured to receive a feed solution through the feed nozzle 48. The liquid collection drum assembly comprises a first enclosure (1) defined with a platform. A second enclosure (2) is concentrically disposed around the first enclosure (1) and is coupled to the first enclosure (1) with a fastening means. In an embodiment, the first enclosure (1) is substantially cylindrical in shape and such construction cannot be considered as a limitation and the first enclosure (1) may be configured in any of a rectangular, square or a polygonal shape based on requirement. A second enclosure (2) is concentrically disposed around the first enclosure (1) such that a diameter of the second enclosure (2) is larger than the first enclosure (1). The second enclosure (2) is also configured to be in a cylindrical shape and is defined with a side wall (20). A collection area (12) is defined between the first enclosure (1) and the second enclosure (2) to receive and retain the micro-droplets after an atomization process. At least one slit (8) is defined on a portion of the first enclosure (1) and on the side wall (20) of the second enclosure (2). Each of the at least one slit (8) of the first and second enclosures (1, 2) are in line with each other. The first and second enclosures (1,2) are fastened to a base (5) to support the liquid collection drum assembly. In an embodiment, the first and second enclosures (1,2) are bolted to the base (5).

[0042] A rotating disc (4) is coupled to the motor unit (6) by a rotating shaft (7) which is rotated at high speeds by the motor unit (6). In an embodiment, the height of the rotating disc (4) is adjustable within the first enclosure (1) by changing the position of the support plate (30) about the support rods (11) with respect to the base plate (32). In an embodiment, the rotating disc (4) may be configured as a flat disc or a cup shaped disc. A non-contact seal (22) is positioned within the liquid collection drum assembly between the rotating shaft (7) and the first enclosure (1). The non-contact seal is defined with two cylindrical compartments (38) of varying diameters placed one above the other. Each of the cylindrical compartments are defined with at least one passage (36) therewith-in for a flow of nitrogen between the rotating shaft (7) and the first enclosure (1) such that the flow of hydrocarbons generated during the atomization process is restricted from entering the motor unit (6).

[0043] In various embodiments, a method 200 for reclaiming polystyrene from waste expanded polystyrene in the form of microparticles or microfibers using the CSDA 300 is disclosed with reference to FIG. 2. The method 300 may include in step 301 providing the SDA 100 as already described with reference to FIG. 1B-1C, with a first feed line I and a second feed line II.

[0044] In various embodiments, the method 200 next includes dissolving 202 predetermined amount of polystyrene in tetrahydrofuran (THF) to get a first feed liquid and a plain THF solvent as a second feed liquid. The method 200 next includes filling the first feed vessel 311a of the first feed line I with the first feed liquid and a second feed vessel 311b of the second feed line II with the second feed liquid. The method 200 next includes, filtering 203, the first feed liquid and the second feed liquid by means of filters 312a, 312b provided in the feed lines I and II to remove solid impurities.

[0045] The method 200 next includes, connecting the first feed line I and the second feed line II with the SDA 100 to produce polystyrene microparticles or only the first feed line I with the SDA 100 to produce polystyrene microfibers.

[0046] The method 200 next includes, mixing 204 the first feed liquid and the THF at controlled rates into a static mixer 315 to vary the concentration of the polystyrene to THF to get a diluted feed liquid to produce microparticles. The method 200 next includes, introducing 206 the final feed liquid or introducing 205 the first feed liquid into a rotating disc of the SDA 100. The method 200 next includes, generating 208 micro-droplets (or) generating 207fluid ligaments at a periphery of the rotating disc 4.

[0047] In various embodiments, the method 200 includes directing 210 the generated micro-droplets from the disc 4 to a precipitation chamber 14 to produce polystyrene microparticles 212 or solidifying 211 the generated fluid ligaments to produce polystyrene microfibers 213.

[0048] In various embodiments, the step 202 includes dissolving predetermined concentration of polystyrene in THF to get the first feed liquid comprises dissolving 20- 30g of polystyrene in 100ml of THF.

[0049] In various embodiments, the production of polystyrene microparticles 212 includes the following steps. Initially the first feed line I and the second feed line II are connected with the SDA 100, the first feed liquid and the second feed liquid are then passed andmixed 204 in the static mixer 315 to vary the concentration of the PS to THF to get a diluted feed liquid at controlled rates then the diluted liquid is introduced 206 into the SDA 100 through a feed nozzle 48 , which produces 208 micro droplets at the periphery of the rotating disc of SDA and the produced droplets are then directed 210 through the at least one slit (8) into the precipitation chamber 14 containing anti-solvent in the plurality of precipitation trays. Lastly, the microdroplets come in contact with the anti-solvent produces polystyrene microparticles 212.

[0050] In some embodiments, the produced droplets are separated from the precipitation chamber and dried to obtain solid polystyrene microparticles 212 of predefined size. In some embodiments the un-dispensed micro-droplets are accumulated in the collection area (12). This accumulated solution is redirected into the first feed vessels after estimating the concentration.

[0051] In various embodiments, the method 200 for obtaining predefined polystyrene micro particles 212 may include adjusting the concentration of the final feed liquid, adjusting the speed of the disc, adjusting the flow rate of the first feed liquid and the second feed liquid to achieve required concentration or adjusting the location of the precipitation tray at a predefined distance.

[0052] In various embodiments, the method 200 may include mixing 204 the first feed liquid at the rate of 3L / h-5L / h and second feed liquid at 9L / h-15L / h thereby achieving 3- 8g of polystyrene per 100ml of THF, maintaining speed of the spinning disc at 3000- 4000rpm and placing the antisolvent tray at 45 to 55cm from the rotating disc 4 produces polystyrene microparticles 212 of a narrow particle size distribution with an average particle size about 90-125 micrometer.

[0053] In various embodiments, the production of polystyrene microfibers includes the following steps, initially the first feed line I is connected with the SDA 100, then the first feed liquid with 22-25g of polystyrene per 100 ml of THF is introduced 205 into spinning disc apparatus 100 through a feed nozzle 48 at controlled rate which produces 207 fluid ligaments at the periphery of the rotating disc of SDA 100 and the produced ligaments are solidified 211 and dried immediately into polystyrene microfibers by supplying 209 nitrogen at the periphery of the disc through a gas distributor 316 placed above the feed nozzle 48. Lastly the produced polystyrene microfibers 213 are collected from the CSDA.

[0054] In some embodiments, the method 200includes directing the accumulated liquid formed during unsteady operation into a collection vessel 12.

[0055] In various embodiments, the method 200 for obtaining predefined polystyrene microfibers may include, adjusting the speed of the disc, adjusting the flow rate of the first feed liquid or adjusting the flow rate of the nitrogen gas.

[0056] In various embodiments,, the method 200 may include introducing 205 the first feed liquid at the rate of 3L / h-5L / h , adjusting the speed of spinning disc in the range 3500-4000 rpm and supplying 209 nitrogen at a flow rate of 9000L / h-10500L / h produces polystyrene microfibers with an average diameter of about 10 ± 4 micrometer.

[0057] In various embodiments, the method 200 produces polystyrene microfibers 213 with nanoporous surface. In various embodiments, the method 200 may include use of two variable area flow meters (rotameter) that measure the flow in the range of 0-30 L / h.

[0058] In various embodiments, the method 200 includes initial calibration of flow meter includes directing the feed liquid to the collection drums, using the drain connection in the feed line. In some embodiments, the drain connections act as the inlet for supplying the flushing solvent to clean the feed system after the operation and the feed nozzle at regular intervals during the operation.

[0059] The proposed method 200 for reclaiming polystyrene from waste expanded polystyrene using CSDA has multiple advantages. Firstly, the disclosed novel method converts waste polystyrene into valuable feedstock in the form of particles or fibers. Conversion of polystyrene waste into valuable products like nano or microparticles and nano or microfibers for several purposes like biomedical applications, imaging, preparation of engineered colloid particles, oil adsorption and so on. Particularly, polystyrene microparticles can be used for lateral flow tests, latex agglutination tests, flow cytometry, fluorescence microscopy, and as calibration particles. Polystyrene microfibers with nanoporous structure are considered to be one of the best oil sorbents to absorb oil from the ocean in case of oil spills. Polystyrene fibers are also used as fiber membranes and as additives in the paint industry.

[0060] EXAMPLES:

[0061] EXAMPLE-1: Determining The Concentrations Of Polystyrene In The Feed Solution For Particle And Fibre Formation In Spinning Disk Equipment

[0062] Determining the accurate concentrations of the polystyrene (PS) in tetrahydrofuran (THF) at which the particles and fibers form is a tedious process. To identify the concentration of PS, instead of using the feed system, a syringe pump set up has been used for conducting the experiments as the feed system may require a lot of volume of solution for each experiment. Hence, experiments were conducted using a syringe pump with two 60mL syringes. The parameters that were changed during the experiment were feed concentration, air pressure and feed flow rate while keeping the disk speed fixed at 3500 rpm. The results of the experiments were analyzed using Scanning Electron Microscope (SEM). The SEM images of microparticles are shown in FIG.3A and 3B, while images of fibers are shown in FIG. 4. A noted feature of the microfibers was the nanoporous surface as shown in FIG. 4 right bottom.

[0063] EXAMPLE-2: Combined Experiment For The Production Of Polystyrene Microparticles And Microfibres

[0064] For the combined design experiment set up, tetrahydrofuran is used as the solvent. EPS waste was dissolved in THF (25g / 100mL) and stirred using a magnetic stirrer for 10 minutes to get a homogenous solution. The feed solution was fed to one of the feed vessels and fresh THF was filled with the other feed vessel. The flow rate of the feed solution was maintained at 3 L / h and the fresh THF flow rate was maintained 3 times the flow rate of feed solution for the production of PS microparticles with the concentration (5g / 100mL of THF) whereas in the case of production of microfibers with concentration (25g / 100ml of THF)the valve of fresh THF will be closed and only the feed solution will be inline. According to the production requirement, the flow rate of the fresh THF can be adjusted. The feed solution is fed to the vessel, disk speed was set at 3500 rpm, the gas distributor flow rate was maintained constantly. The microparticles or microfibres are formed according to the requirement by adjusting the values of process variables.

[0065] Both microparticles and microfibers are produced by varying the process conditions using the same spinning disk equipment. Analysis of the microscopy images of polystyrene microparticles collected at a particular distance from the spinning disk indicates a narrow size distribution with an average particle size 107 pm as shown in FIG.5A and FIG. 5B. This suggests that, using SDA technique, conversion of EPS to polystyrene microparticles of narrow size distribution can be achieved in a controlled and reproducible manner. The microfibers produced by spinning disk with drying technique had nanoporous structure at the surface with an average fiber size 10 pm as shown in FIG. 6. Using SDA equipment with two feed systems and by altering the concentration of the feed liquid, microparticles or microfibers production can be achieved by the same equipment.

[0066] Although the detailed description contains many specifics, these should not be construed as limiting the scope of the invention but merely as illustrating different examples and aspects of the invention. It should be appreciated that the scope of the invention includes other embodiments not discussed herein. Various other modifications, changes and variations which will be apparent to those skilled in the art may be made in the arrangement, operation and details of the system and method of the present invention disclosed herein without departing from the spirit and scope of the invention as described here, and as delineated in the claims appended hereto.

Claims

WE CLAIM:

1. A method (200) for reclaiming polystyrene (PS) from waste expanded polystyrene in the form of microparticles or microfibers using a customized spinning disc apparatus(CSDA) (300), the method comprising: providing (201) a spinning disc apparatus (SDA)(100); dissolving (202) 20-30g of waste polystyrene in 100 ml of tetrahydrofuran (THF); filtering (203) to remove solid impurities to get a first feed liquid; mixing (204) the first feed liquid and THF as a second feed liquid at controlled rates into a static mixer (315) to vary the concentration of the PS to THF to get a diluted feed liquid to produce microparticles; wherein the flow rate of the first feed liquid at 3L / h-5L / h and the second feed liquid at 9L / h-15L / h, thereby achieving the diluted feed liquid with 3-8g of polystyrene in 100ml of THF; introducing the diluted feed liquid (206) or the first feed liquid (205) into the spinning disc apparatus (100); generating micro-droplets (208) or fluid ligaments (207) at a periphery of the rotating disc (4); and directing (210) the generated micro-droplets from the disc (4) to a precipitation chamber (14) having antisolvent to produce (212) polystyrene microparticles or solidifying (211) the generated fluid ligaments to produce (213) polystyrene microfibers.

2. The method (200) as claimed in claim 1, wherein directing (210) the generated micro-droplets from the disc (4) to a precipitation chamber (14) having antisolvent, to produce (212) polystyrene microparticles, includes the steps of: solidifying the microdroplets in the precipitation chamber (14); separating the particles collected in the precipitation chamber (14) from the antisolvent; and drying the particles to obtain solid polystyrene micro-particles in the range 90-125 microns.

3. The method (200) as claimed in claim 2 wherein obtaining polystyrene microparticles comprises adjusting one or more of: the concentration of the final feed liquid; the speed of the spinning disk; the flow rate of the first feed liquid and second feed liquid to achieve the required concentration; and the location of the antisolvent tray at a predefined distance.

4. The method (200) as claimed in claim 3, comprising maintaining speed of the spinning disc at 3000 -4000 rpm.

5. The method (200) as claimed in claim 3, comprising locating the antisolvent tray at a predefined distance of 45 to 55 cm from the center of the disc (4).

6. The method (200) as claimed in claim 1, wherein solidifying (209) the generated fluid ligaments into polystyrene microfibers, includes the steps of: supplying (209) nitrogen at the periphery of the rotating disc and drying the generated fluid ligaments into microfibers by the nitrogen; and collecting (213)the polystyrene microfibers from the apparatus (300).

7. The method (100) as claimed in claim 6, wherein obtaining polystyrene microfibers with an average diameter of about 10 ± 4 micrometer comprises adjusting one or more of: the flow rate of first feed liquid; the speed of the spinning disk; and the nitrogen flow rate.

8. The method (200) as claimed in claim 7, comprising introducing (205) the first feed liquid at controlled rate of 3L / h to 5L / h.

9. The method (200) as claimed in claim 7, comprising adjusting the speed of spinning disc in the range 3500-4000 rpm.

10. The method (200) as claimed in claim 7, comprising supplying (209) nitrogen at a flow rate of 9000L / h-10500L / h.

11. The method (200) as claimed in claim 1, wherein reclaiming polystyrene in the form of microfibers comprises feeding 22-25 g of polystyrene in 100 ml THF.

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