Paper id 23201432

International Journal of Research in Advent Technology, Vol.2, No.3, March 2014

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Preparation, Characterization and Application of Ultra Filtration (UF) Membranes

Rajesh Tripathy Department of Chemical Engineering, G H Patel College of Engineering & Technology,

BakrolRoad,Vallabh Vidyanagar-388 120.Gujarat. India. Email: [email protected]

Abstract-In recent years, membranes and membrane separation techniques have grown from a simple laboratory tool to an industrial process with considerable technical and commercial impact. Today, membranes are used on a large scale to produce potable water from the sea by reverse osmosis, to clean industrial effluents and recover valuable constituents by electro dialysis to fractionate micro molecular solutions in the food and drug industry by ultra filtration, to remove urea and other toxins from blood stream by dialysis in an artificial kidney, to recover valuable products from waste like protein from waste whey and to release drugs such as scopolamine, nitroglycerine etc. at a predetermined rate in medical treatment.Although membrane processes may be very different in their mode of operation in the structures used as separating barriers. In many cases, membrane processes are faster, more efficient and more economical than conventional separation techniques such as distillation, extraction, adsorption, and absorption.[1,8] Index Terms-commercial impact, scopolamine, nitroglycerine, ultrafiltration

1.0 INTRODUCTION Membranes have gained an important place in chemical technology and are used in a broad range of applications. The key property that is exploited is the ability of a membrane to control the permeation rate of a chemical species through the membrane. In controlled drug delivery, the goal is to moderate the permeation rate of a drug from a reservoir to the body. In separation applications, the goal is to allow one component of a mixture to permeate the membrane freely, while hindering permeation of other components. This paper provides a general introduction to membrane science and technology and cover Preparation, Characterization and Application of Ultra Filtration (UF) Membranes, that is topics that are basic to all membrane processes, such as transport mechanisms, membrane preparation, and boundary layer effects, cover the industrial membrane separation processes, which represent the heart of current membrane technology .Carrier facilitated transport is covered next, followed by reviewing the applications of membranes. The paper closes with that describes various minor or yet tobedeveloped membrane processes, including membrane reactors, membrane contactors for the separation of protein from different west, before disposal.

1.1 Membrane Separation Processes All the membrane technologies are essential separation technologies depending upon size of the constitutes to be separated or on the ionic charges or absence of charges, diffusion into the matrix or some such transport phenomena. Keeping this in mind it is essential to mention here that none of the membrane technologies destroy the pollutants; they either separate or concentrate them for further easy handling. Membranes can be classified into 4 categories depending on the size of the materials they remove from the carrier liquid. The 4 categories, listed from the largest to the smallest pore size, are (a)Micro Filtration (MF) (b)Ultra Filtration (UF) (c)Nano Filtration (NF) (d)Reverse Osmosis (RO) a) Microfiltration (MF):MF is a low-pressure membrane process (0.3 to 3.3 bar) that removes particulate material ranging in size from 0.1 to 1.0 microns (1,000 to 10,000 angstroms) and larger. MF is used for separating suspended or colloidal materials from a feed stream. Water, salts, and selected macromolecules pass through the semi-permeable membrane, and suspended solids are progressively concentrated. In the case of water, bacteria (like Escherichia coli, Cryptosporidium parvum, or Giardia lamblia) can be separated from water with this


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technique. The salient features of the process are that it involves no phase change and it is relatively a low energy process. b) Ultrafiltration (UF):UF is a low-pressure membrane process (0.5 to 10 bars) that separates materials in the 0.001 to 0.1 micron range (10 to 1,000 angstroms). UF is used for the separation of high molecular weight dissolved materials (solute). Water, salts, and low molecular weight species selectively pass through the semi-permeable membrane, and macromolecules and suspended solids are retained (progressively concentrated). UF separates bacteria and viruses from the water stream that MF passes because the pore size is smaller. c) NanoFiltration (NF):NF is a high-pressure membrane process used for separating materials less than 0.001 microns (10 angstroms) in size. NF is used for the separation of dissolved materials (solute). Less expensive, NF is not as fine a filtration as RO, but it also requires less energy to perform the separation (i.e. less operation & maintenance cost). In water, NF is very effective in removing hardness (multiple-charged ions), total dissolved solids, and natural organic material (Disinfection-By-Product DBP precursor material) with MF pre-filtration. NF is also known, in the water markets, as the "Membrane softening". d) Reverse osmosis (RO):RO membranes have the smallest pore structure, with pore diameter ranging from approximately 5-15 A0 (0.5 nm - 1.5 nm). The extremely small size of RO pores allows only the smallest organic molecules and unchanged solutes to pass through the semi-permeable membrane along with the water. Greater than 95-99% of inorganic salts and charged organics will also be rejected by the membrane due to charge repulsion established at the membrane surface.

2.0 MATERIALS FOR MEMBRANE MANUFACTURING Pressure driven membrane separation processes fall into four broad categories: microfiltration, ultrafiltration, nanofiltration and reverse osmosis. The materials used for the preparation of these membranes, their morphological characteristics as well as their applications are different from each other. Morphologically the membranes are essentially porous in nature. Pore size in case of microfiltration

membranes is in the order of 200 A0 (0.02 microns) to 1,00,000 A0 (10 microns); in ultrafiltration the pore size is between of 20A0-200A0; in nanofiltration it is in the range of 10A0-20A0 and in the case of reverse osmosis it is between 1A0-10A0. Mechanisms of separation are also different for these membrane processes. While size based separations occur in case of microfiltration and ultrafiltration, membrane-solute interaction is the basis in nanofiltration and reverse osmosis. Application wise, microfiltration is used for the separation of solutes having molecular weight more than 3,00,000 Daltons, ultrafiltration is used for solutes in the range of 500-3,00,000 Daltons, nanofiltration is used for separation of solutes with a molecular weight range of 300-500 Daltons and reverse osmosis is used for the separation of solutes with molecular weight up to 300Dalton. Microfiltration is used for separation of suspended materials, coarse colloids, etc., ultrafiltration is useful in case of separation of soluble macromolecules, sugars, proteins, etc., nanofiltration is used in the separation of multivalent ions and reverse osmosis is used for the separation of ionic solutions. The membranes are predominantly polymeric in nature and is thin sheet like materials having typical thickness of the order of 100 microns. It forms a physical barrier between the fluids on either side, yet keeping communication between them. The crucial feature of a particular membrane is its selective permeability to certain species for which certain force is needed for the movement of species through the membrane. The overall driving force in the transport of species across the membrane is the chemical potential gradient, which is the sum of existing gradients such as concentration, pressure and electrical potential. In RO, water molecules are forced through the membrane by applying pressure. Material used for membranes are predominantly polymeric in nature. For RO, polymers such as cellulose acetate, polyamide, polyimide deposited on polysulphone base support etc. are used, whereas in ultrafiltration, the membrane used is made up of polysulfone and poly acrylonitrile.[7]

2.1 Membrane Materials: These can be classified as (a) inorganic and (b) polymeric.


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(a) Inorganic: Typical are gamma-alumina, alpha-alumina, borosilicate glass, pyrolyzed carbon, Zirconia/s. steel Zirconia/ carbon, etc. Other types of ceramic membranes are also being developed. Inorganic membranes have certain advantages over polymeric ones, like temperature and chemical stability. The cost of these materials and packing density (area /volume ratio) being the main restriction towards their large -scale applications. (b) Polymeric: typical materials, for Ultrafiltration are polysulphones, polyethersulphone cellulosic materials polyvinylidenefluoride, polyacrylonitrile, polyamides, etc the membranes are typically made by the phase inversion method. Behavior, performance, and limitations of some of the polymeric membrane are given below [1,2] 1) Cellulose Acetate (CA) Raw material used is cellulose, which undergoes acetylation in presence of acetic anhydride, acetic acid and sulphuric acid. It is extensively used in UF studies as it is easy to fabricate less costly high salt retention and relatively high flux .The raw material cellulose is a renewable source. But it also has some drawbacks. Firstly it has fairly narrow range and maximum temperature recommended is 30 0C. This creates problems in maintaining sanitary condition and give lower flux .The PH range is also restricted between 2-8. Under acidic conditions polymer hydrolyses & structural integrity is lost. Under highly alkaline condition, deacetylation occurs, which will affect selectively, permeability. Also cellulose acetate has a poor resistance to chlorine .It also undergoes compaction and creep to a slightly greater extent pressure. Cellulose acetate is also biodegradable and hence storage properties. 2) Aromatic polyamides (PA) It is also an important material for UF .It is characterized by the having an amide bond in its structure (--CONH--). In general they show good temperature resistance even up to 80 0C .The PH resistance is also good between range 3-11 at 25 0C .PA membranes are not biodegradable. Cleaning PA with acid caustic solutions is feasible but they are more sensitive to chlorine to CA and only polybenimidazole appears to show some resistance. 3) Polysulfone (PS)

PS is most widely used in UF. These membranes are characterized by having in its structure diphenylenesulfonerepeating units.It has wide temperature limits from 750C –1250C. Wide PH tolerance from 1-13. It has fairly good resistance and also it is not biodegradable. It is easy to fabricate membranes n wide variety of configurations and wide range of pore sizes. Cleaning using acids and bases and disinfections, using chlorine and H2O2 are feasible. PS is also resistant to strong oxidizing agent. Polysulfone has the apparent low-pressure limit. 4) PAN (Polyacrylonitrile) PAN is hydrophilic in nature. It is not affected by boiling water .It is not affected by weak acids, weak alkalis but affected by strong acids & alkalis. It can be used up to 180 0C.Oxidising agent & common organic solvents have little effect. PAN membranes are hard, relatively insoluble & high melting material. 5) Polyethersulfone (PES): PES is an amorphous material with a translucent amber tint. It has excellent dimensional stability and very good electrical insulation properties. It is also characterized by its creep resistance - substantial loads can be carried for long periods at temperatures up to 180°C - and thermal stability PES parts can be used for thousands of hours up to 200°C with no significant loss of strength. It has relatively high water absorption and, in common with many other plastics, drying is essential before e.g. thermoforming. It has poor fatigue characteristics and is prone to environmental stress cracking but has good long-term thermal ageing resistance and reasonable radiation resistance. 2.2 Selection Of Material It is evident that for selecting a membrane material which would be the best choice, it is necessary to consider operating condition like temperature, pressure; the nature of feed stream i.e. the pH, viscosity, density etc. and other factors like solid contents clean ability. Although the inorganic materials are having more temperature and pressure resistant, they can be used in very high or very low pH, we have chosen polymer membrane for casting and to study performance because polymer membranes are flexible in nature and can be casted in any shape but not the inorganic materials. Inorganic membranes are more tough cannot be casted easily.


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There are many polymer membrane materials as discussed above but we have chosen polyethersulfone as a casting material because lot of study is done on other materials but polyethersulfone is not yet explored much as compared to other materials. Before going into details of the casting and performance study we will see some important physical and chemical properties of the polyethersulfone. Membrane materials characteristics

a. The ideal membrane has the following characteristics:

b. High water flux rates c. High salt rejection d. Tolerance to chlorine and other oxidants e. Resistance to biological attacks f. Resistance to Fouling by colloidal and

suspended material g. Inexpensive h. Mechanical strength i. Chemical stability

2.3 Membranes Used in present work : Polymeric - polysulfone/poly(ether sulfone)/sulfonatedpolysulfone - poly(vinylidene fluoride) - polyacrilonitrile - cellulosics - polyimide/poly(ether imide) - aliphatic polyamides - polyetheretherketone Ceramic - alumina (Al2O3) - zirconia (ZrO2) Solvent Used: -Dimethylformamide(DMF) -N, N-Dimethylacetamide.(DMAC) -Dimethylsulfoxide (DMSO) -N-Methylpyrrolidone(NMP) -Morfoline

3.0Membrane Preparation Technique Anumber of different techniques are available to prepare synthetic membranes. Some of these techniques can be used to prepare organic (polymeric) as well as inorganic membranes. The most important techniques are:

a. Sintering b. Stretching c. Track-etching d. Phase Inversion e. Coating

Most commercially available membranes are obtained by phase inversion. This is a very versatile technique allowing all kind of morphologies to be obtained. This preparation technique is detailed as follows. Phase inversion is a process where a polymer is transformed in a controlled manner from a liquid to a solid state. The process of solidification is very often initiated by the transition from one liquid state in to two liquids (liquid0liquid demixing). At a certain stage during demixing one of the liquid phases (high polymer concentration phase) will solidify so that matrix is formed. By controlling the initial stage of phase transition the membrane morphology can be controlled, i.e., porous as well as nonporous membranes can be prepared. It covers different techniques like

a. Solvent evaporation b. Precipitation by controlled evaporation c. Thermal precipitation d. Precipitation from the vapour phase e. Immersion precipitation

The most commercially available membranes are prepared by immersion precipitation: a polymer solution (polymer + solvent) is cast on a suitable support and immersed in a coagulation bath containing a nonsolvent. Precipitation occurs because of the exchange of the solvent and nonsolvent. The membrane structure ultimately obtained results from the combination of mass transfer and phase separation.


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3.1 Phase Inversion Process Of Membrane Manufacture: This refers to a method of manufacturing asymmetric membranes that result in a “solvent cast structure, which owes it porosity to immobilization of the polymer gel prior to complete solvent evaporation or depletion. This is accomplished by not allowing the cast solution to evaporate to dryness before its structure is set; partial solvent loss occurs so that the solution separates into two interspersed liquid phases. One of these phases represents the voids. As evaporation is allowed to continue, gel structure is set”. [1,8] The steps involved in preparation of Polysulfone membrane are,

a. Preparation of polymer solution. b. Casting c. Gelation d. Annealing.

Preparation of polymer solution The major constituents of Polysulfone membrane are classified into three types a) polymer base b) solvent and c) swelling agents (magnesium perchlorate or formamide). In addition few more chemicals may be added imparts certain properties of the membranes. Sometimes filler chemicals are also added with co-polymers to form better polymer chain links and improve mechanical strength. A clean, dry, glass beaker, washed with hydrochloric acid, is taken. It is then rinsed with acetone and kept to dry. The specific quantity of Polysulfone is poured into the beaker, which is followed by dimethylformamide. The stirring is stated at this point in order to get a homogeneous material. The remaining chemicals are then added slowly under continuous stirring using a glass stirrer. Proper care was taken to prevent the evaporation of solvents during the process. The polymerization was carried out for 4-5 hours. After this period, a viscous solution with lots of air bubbles trapped in it is obtained. The air bubbles trapped in it are removed by keeping the solution still for 3-4 hours. Thus a clear viscous solution is obtained Casting: The casting of Polysulfone membrane is done in a module. E.g. Flat sheet membranes are made by drawing the polymer solution over a glass plate using a “thin layer chromatography unit”. When this solution is cast and the solvent allowed to evaporate, it results

in an increased concentration of polymer at the solution/ air interface, since solvent is lost more rapidly from the surface. The polymer essentially goes out of solution at the surface and forms the so-called skin layer that is characteristic of asymmetric membranes. (This phenomenon is analogues to “case hardening” in products that have been rapidly dried.). After the skin forms, the remaining solvent in the bulk of the mixture evaporates more slowly. Eventually the swelling agent in the mixture starts separating out as a different phase, resulting in two phases within the substructure: the polymer solvent as the concentrated phase and the swelling agent as the dispersed phase. Gelation: The polymer film this formed is further consolidated by a process of gelation. Here, the polymer chain is uniformly linked and distributed in the proper orientation for flow of permeate. Gelation is obtained by keeping the membrane in water at a low temperature of about 5-6 oC. Annealing: The polymer film thus produced, having a hard crust layer on spongy porous support, is still mechanically weak and highly compressible. With application of pressure the pores can be easily stretched. These are hardened with consequent shrinkage of pores by means of proper heat treatment of the membrane. This can be achieved by the process of annealing.The peeled sheet is immersed in hot water for a period of five minutes; the membrane is maintained at 70oC. Product flux and solute rejection can be controlled buy a process condition of this step. Higher temperature causes a decrease in flux of product water and an improvement in solute rejection and vise –versa. Since the degree of rejection can be adjusted by changing the heating temperature, this step is very important in membrane preparations. 3.0 RESULTS AND DISCUSSION 3.1 Analysis of Protein Solution To study the performance of ultrafiltration membrane experimentation is done on dairy whey /milk/protein solution .In this report, to study the performance of PS membrane which are casted in laboratory, the standard protein solution is used. The concentration of BSA protein solution used for experimentation is 0.5%.


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0

0.05

0.1

0.15

0.2

0.25

0.3

0.35

0.4

0 0.2 0.4 0.6

Abs

orba

nce

protein conc. (%)

Series2

Linear (Series2)

First of all protein solution is prepared, then by biuret method calibration chart is plotted. Then this calibration chart is used for determination of concentration of permeate. The standard protein solution is prepared as follows, 1. Preparation of standard BSA solution Take 50 mg of BSA protein powder in conical flask and dilute it in 10 ml of distilled water. Then the standard protein solution i.e. the solution having 0.5 % concentration will be ready for membrane characterization. First of all by using this BSA solution one can plot a calibration curve, which will be helpful for the analysis of permeate obtained stirred cell apparatus. 3.2. Analysis of BSA by Biuret Method a) Preparation of biuret reagent: Dissolve 9 gms. of sodium potassium tartarate in approximately 400 ml of 0.2 N NaOH. Dissolve separately 3 gm of CuSO4.H2O in minimum quantity of distilled water & transfer slowly with constant stirring to sodium potassium tartarate. Then add 5 gm of potassium iodide & adjust the whole solution to 1000 ml by addition of 0.2 N NaOH. b) Preparation of calibration chart: Six test tubes were taken. A sample of BSA solution of 0.5% concentration and water were prepared in six test tubes according to the table given. And four ml of biuret reagent was added in each test tube. Incubate this solution at room temperature for ½ an hour and absorbance was measured at 530 nm for the respective samples in spectrophotometer. The respective absorbance with different concentration of protein solution is shown in table 5.1. Now the absorbance at the respective concentration is known so the calibration curve between absorbance and protein concentration is drawn as shown in figure 1.

Table .1 Calibration chart. Std .BSA ml

Distilled

water ml

Biuret Reage

nt ml

Protein concentration (wt/vol)

%

Absorbance

At 530 nm

0.0 1.0 4 0.0 -- 0.2 0.8 4 0.1 0.094 0.4 0.6 4 0.2 0.2 0.6 0.4 4 0.3 0.217 0.8 0.2 4 0.4 0.283 1.0 0.0 4 0.5 0.333

Figure 1. Calibration Curve

From this calibration curve concentration of permeate (less than 0.5% concentration) can be obtained. This calibration curve has a limitation that conc. more than 0.5% can not be taken in a feed as the curve shows straight line nature up to 0.5% concentration.

3.3 Stirred cell Apparatus Construction: The stirred cell apparatus consist of [1]

a. Cell cylinder b. Pressure gauge c. Compressor d. Magnetic stirrer

A] Cell cylinder: It consists of a. Pressure inlet: For applying pressure to feed. b. Pressure release valve: To release pressure in

the cell cylinder. c. Transparent acrylic body. d. O – ring: To fit the membrane on membrane

support. e. Stirring bar: For stirring of solution. f. Membrane g. Membrane support: To fit the membrane in

cell cylinder. h. Filtrate out: To collect the permeate.

B] Pressure gauge: It is used to apply the pressure inside the cell. C] Compressor: Compressed air is sent at 1 – 2 kg/cm2 in cell cylinder. D] Magnetic stirrer: Cell cylinder is mounted on magnetic stirrer which in tern is used to stir the stirring bar placed inside the cell cylinder.


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Figure 2. (a) Stirred cell Apparatus schematic diagram

Figure 2.(B)Working model of Stirred cell

ApparatuswithUltrafiltration of BSA Protein solutions.

Working: Part A: Measurement of Distilled water flux. Take 50-60 ml of distilled water in stirred cell. Start magnetic stirrer. Maintain moderate rpm. Start Air compressor and maintain the pressure on the pressure gauge as 1 Kg/Cm2 .As soon as the pressure is developed, start the stopwatch. Note down Time required to collect 1 ml of permeate. Take 30-40 readings.

Part B: Measurement of BSA Protein solution flux/ milk flux/Whey Flux. Take 50-60 ml of known concentration of protein solution/whey/milk as feed solution in stirred cell. Start magnetic stirrer. Maintain moderate rpm. Start Air compressor and maintain the pressure on the pressure gauge as 1 Kg/Cm2 .As soon as the pressure is developed, start the stopwatch. Note down Time required to collect 1 ml of permeate. Take 30-40 readings. Part C: Measurement of volume concentration factor. The stirred cell experiment as mentioned in measurement of BSA protein solution flux was performed. After 5 minutes amount of permeate collected was noted and after each 4 ml time required was noted. 3-4 readings were taken. VCF is calculated by,VCF= volume of feed / volume of rententate Part D: Measurement of Rejection The standard stirred cell experiment for BSA protein solution was performed and after 4 ml time required to collect permeate was noted and flux is calculated. The absorbance of each 4ml permeate was noted and overall absorbance was noted. Permeate concentration was calculated from the calibration curve. The Rejection is calculated by R = 1-Cp / Cf Where,Cp: Concentration of permeate in % wt / vol

Cf: Concentration of feed in % wt / vol 4.0 MEMBRANE CHARACTERIZATION 1. Thickness: The thickness of standard UF membrane ranges from 20 – 100 micron. The thickness of casted membrane is measured with the help of micrometer screw gauge at different points on the membrane and the average thickness is calculated. It is used in the measurement of pore diameter and porosity. 2. Porosity: Porosity is the ratio of pore volume of the membrane to the total volume of membrane. It is calculated as follows, 1. Take wt. of wet membrane (in water). 2. Dry the membrane in oven for few minutes & take its dry weight. 3. Take the difference & multiply with density of water that will give you the pore volume of membrane. 4. From area & thickness of membrane calculate volume of membrane.

International Journal of Research in Advent Technology, Vol.2, No.

5. Ratio of pore volume to membrane volume will give you porosity. Porosity = pore volume/ membrane volume5 .0 MATERIALS AND METHODS5.1. Materials Polysulfone (PS) in powder form was obtained from M/s. Gharda Chemicals Company, India. The solvents used for membrane making are N,Nformamide (DMF) and were of reagent grade. Polyethylene glycol (PEG), Polyvinyl Pyrrolidone (PVP K-30) of different molecular weights and piperazine (AR grade) were locally procured and used as additives. 5.2. Preparation of membrane In airtight glass bottle, a specified quantity of polymer was taken and then a known quantity ofthe solvent was added. The solution wfor several hours for complete dissolution.Calculated quantities of additives were subsequently added and the solution was homogenizedand kept for deairation. The solution viscosity was measured using a standard Brookfield viscometer.The dope solution thus obtained was spread over a smooth glass plate with the help of a knife edge. The thickness of the membranes was controlled by varying the thickness of adhesive tapes at the sides of the glass plate. The glass plate was kept in an environment of controlled temperature and humidity during membrane casting. No deliberate solvent vaporation period was allowed. The glass plate was subsequently immersed in a gelling bath, which is generally demineralized water maintained at a known temperature otherwise as mentioned in the text.Immediately phase inversion starts and after fewminutes thin polymeric film separated out from the glass. It was repeatedly washed with demineralized water and wet stored. The actual thickness of the membranes was measured using a micrometer.

Table 2. Dope solution compositions

Dope PS

Composition in Wt. %

PS

Solution DMF

Additiv

M 1 16 84.9 M 2 16 80.6 M 3 16 74.3


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5. Ratio of pore volume to membrane volume will give

Porosity = pore volume/ membrane volume 5 .0 MATERIALS AND METHODS

Polysulfone (PS) in powder form was obtained from M/s. Gharda Chemicals Company, India. The solvents used for membrane making are N,N-dimethyl formamide (DMF) and were of reagent grade. Polyethylene glycol (PEG), Polyvinyl Pyrrolidone

nt molecular weights and piperazine (AR grade) were locally procured and used

In airtight glass bottle, a specified quantity of polymer was taken and then a known quantity of the solvent was added. The solution was kept agitated for several hours for complete dissolution.Calculated quantities of additives were subsequently added and the solution was homogenizedand kept for deairation. The solution viscosity was measured using a standard

ope solution thus obtained was spread over a smooth glass plate with the help of a knife edge. The thickness of the membranes was controlled by varying the thickness of adhesive tapes at the sides of the glass plate. The glass plate was kept in

ent of controlled temperature and humidity during membrane casting. No deliberate solvent vaporation period was allowed. The glass plate was subsequently immersed in a gelling bath, which is generally demineralized water maintained at a known

therwise as mentioned in the text.Immediately phase inversion starts and after fewminutes thin polymeric film separated out from the glass. It was repeatedly washed with demineralized water and wet stored. The actual thickness of the

using a micrometer. Dope solution compositions

Additive 1

Wt. %

Additive 2

Wt. % 0 3.5 4 3.5 10 3.5

Results of M-1

Table 3.Effect of the time on the Membrane Flux

Figure 3.Effect of the time on the performance of

Membrane Flux


Membrane Flux

Sl No Volume in ml

DW 1 mlM 1.1 BSA 1 0-5BSA 2 05--10BSA 3 10--15BSA 4 15-20M 1.2

P Whey1 0-5P Whey2 05--10P Whey3 10--15P Whey4 15-20


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Effect of the time on the performance of Membrane Flux


Membrane Flux model M 1.1


Membrane Flux model M 1.2

Volume in ml

Time in Sec

Flux lt/hr.m2

1 ml 190 20.105

5 212 18.019 10 267 14.307 15 295 12.94 20 308 12.4

5 493 7.74 10 520 7.34 15 551 6.93 20 606 6.303


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Table 4. Effect of the Pressure on the performance of Membrane Flux

Sl No Pressure kg/cm2

Time in Sec

Flux lt/hr.m2

M1.3 DW 1 0.50 306 12.48 DW 2 1.00 190 20.1 DW 3 1.20 180 21.22 DW 4 1.40 163 23.43 M1.4 BSA 1 0.50 277 13.79 BSA 2 1.00 213 17.93 BSA 3 1.20 185 20.64 BSA 4 1.40 160 23.87

Figure 5.Effect of the Pressure on the performance of

Membrane Flux M 1.3

Figure 6.Effect of the Pressure on the performance of Membrane Flux M 1.4

Results of M-2

Table 5.Effect of the time on the performance of Membrane Flux

Sl No Volume in

ml Time in

Sec Flux

lt/hr.m2 DW 1 ml 19 201.05

M 2.1 BSA 1 0-5 52 73.46 BSA 2 05--10 70 54.57 BSA 3 10--15 90 42.44 BSA 4 15-20 103 37.08 M 2.2

P Whey1 0-5 109 35.046 P Whey2 05--10 151 25.29 P Whey3 10--15 163 23.43 P Whey4 15-20 174 21.95

Figure 7..Effect of the time on the performance of

Membrane Flux M 2.1

Figure 8.Effect of the time on the performance of Membrane Flux M 2.2

M 1.3

0

5

10

15

20

25

0.00 0.20 0.40 0.60 0.80 1.00 1.20 1.40 1.60

Pressure in Kg/cm2

Flu

x

M 1.4

0

5

10

15

20

25

30

0.00 0.20 0.40 0.60 0.80 1.00 1.20 1.40 1.60

Pressure in Kg/cm2

Flu

x

M 2.2

0

5

10

15

20

25

30

35

40

0 20 40 60 80 100 120 140 160 180 200

Time in Sec

Flu

x

M 2.1

0

10

20

30

40

50

60

70

80

0 20 40 60 80 100 120

Time in Sec

Flu

x


Table 6.Effect of the Pressure on the performance of Membrane Flux

Figure 9. Effect of the Pressure on the performance of

Membrane Flux M 2.3


Membrane Flux M 2.4


Time in Sec

M 2.3 DW 1 0.50 33 DW 2 1.00 19 DW 3 1.20 16 DW 4 1.40 12 M 2.4 BSA 1 0.50 148 BSA 2 1.00 58 BSA 3 1.20 52 BSA 4 1.40 50


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Effect of the Pressure on the performance of Membrane Flux

Pressure on the performance of

M 2.3


Membrane Flux M 2.4

Results of M-3

Table 7. Effect of the time on the performance of Membrane Flux

Sl No Volume

in ml DW 1 ml

M 3.1 BSA 1 0-5 BSA 2 05--10 BSA 3 10--15 BSA 4 15-20 M 3.2

P Whey1 0-5 P Whey2 05--10 P Whey3 10--15 P Whey4 15-20

Figure 11. Effect of the time on the performance of Membrane Flux M 3.1

Figure 12. Effect of the time on the performance of Membrane Flux M 3.2

Time in Sec

Flux lt/hr.m2

115.75 201.05 238.75 318.33

25.81 65.85 73.462 76.4


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Effect of the time on the performance of Membrane Flux Volume Time

in Sec Flux

lt/hr.m2 26 146.92

90 42.44 144 26.52 160 23.87

179 21.34

192 19.89 230 16.6 283 13.49

310 12.32

the time on the performance of Membrane Flux M 3.1

. Effect of the time on the performance of Membrane Flux M 3.2


Results of M-3

Table 8.Effect of the Pressure on the performance of Membrane Flux


Time in

SecM 3.3 DW 1 0.50 38DW 2 1.00 26DW 3 1.20 20DW 4 1.40 18M 3.4 BSA 1 0.50 87BSA 2 1.00 75BSA 3 1.20 64BSA 4 1.40 60

Figure 13.Effect of the Pressure on the

Membrane Flux M 3.3


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Effect of the Pressure on the performance of Membrane Flux

Time in

Sec Flux

lt/hr.m2

100.52 146.92 191 212.22

43.9 50.93 59.93 63.66


M 3.3


Membrane Flux M 3.4

6.0 CONCLUSION AND FUTURE SCOPEAseries ofUtrafiltration PS membrane was successfully casted & performance was studied for MM – 3 (distinction based on polymer concentration and additive concentration and the effect with different solvents).Stirred cell operation was performed with standard Bovoin Serum Albumin (BSA) protein solution (0.1 % concentration).,Distilled water flux, Dairy Waste with different pressure range starting from 0.5-1.4 kg /cm2.We have observed that for three membranes as the time increases flux goes on decreases due to fouling.Rejection increases with increase in PS concentration in ultrafiltration membrane. Presence of additives improves the viscosity of the solution. The pure water permeation rate is found to be significantly higher for Mcompared to M-1.Incorporation of additives in the casting solution generally increase the water permeation rate. It can be observed from the several castings that exposure to higher ambient humidity gives more porous membranes with higher water permeation rate in all the cases it happens due to partial phase separation during membrane casting. It can be seen that the permeate flux as well as solute separation increase in applied pressure range studied.We have studied two characteristics (thickness, porosity) of casted membranes & remaining characteristics of the membrane can be studied in future. REFERENCES

[1] “Encyclopedia of Polymer science and Technology” 3rd Edition Vol

[2] Mark C. Potter; Handbook of industrial membrane technology, No Yes publications.

[3] Mohr; Membrane application and research in food processing.

[4] Richardson Coulson; chemical engineering, volume 2, second edition; Tata McGraw hill publishers, USA.

[5] KatarzyanaMajewska- 1989, Elseveir science publishers, Page no. 83 95.

[6] Synthetuc Polymeric Membrane,Robert E.Kistinkg and Irvine California, A Wiley-Interscience Publication

[7] Miss. ShilpaChitnis, Miss. Deval Desai, Miss VinayaPrabhu; A project report on Kinetic study of PAN membrane by phase inversion


49


Membrane Flux M 3.4

6.0 CONCLUSION AND FUTURE SCOPE Aseries ofUtrafiltration PS membrane was successfully casted & performance was studied for M– 1,M– 2 and

(distinction based on polymer concentration and additive concentration and the effect with different solvents).Stirred cell operation was performed with standard Bovoin Serum Albumin (BSA) protein solution (0.1 % concentration).,Distilled water flux,

Waste with different pressure range starting from We have observed that for three

membranes as the time increases flux goes on decreases due to fouling.Rejection increases with increase in PS concentration in ultrafiltration

ence of additives improves the viscosity of the solution. The pure water permeation rate is found to be significantly higher for M-2 as

1.Incorporation of additives in the casting solution generally increase the water

be observed from the several castings that exposure to higher ambient humidity gives more porous membranes with higher water permeation rate in all the cases it happens due to partial phase separation during membrane casting. It can be

eate flux as well as solute separation increase in applied pressure range studied.We have studied two characteristics (thickness, porosity) of casted membranes & remaining characteristics of the membrane can be studied in future.

of Polymer science and Edition Vol-3 Page(184-245)

Mark C. Potter; Handbook of industrial membrane technology, No Yes publications. Mohr; Membrane application and research in

Richardson Coulson; chemical engineering, volume 2, second edition; Tata McGraw hill

Nowak; Desalination, 1989, Elseveir science publishers, Page no. 83 –

Synthetuc Polymeric Membrane ,2nd Edition ,Robert E.Kistinkg and Irvine California, A

ience Publication Miss. ShilpaChitnis, Miss. Deval Desai, Miss

A project report on Kinetic study of PAN membrane by phase inversion, 1997 – 98.


E-ISSN: 2321-9637

50

[8] MunirCheryan; Ultrafiltration and Microfiltration handbook; 1998; Tchnomic publishing company.

[9] Wenli Han, Harry P Gregar, Eli M. Pearce; Acrylonitrile copolymers, synthesis characterization and formation of ultrafiltration membranes; capanneli et al (1983); Page no. 1271 – 1277.

[10] B. W. Baker, Membrane Technology & Applications, John Wiley & Sons, Ltd.

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