International Journal of Mechanical Engineering and Technology (IJMET) IAEME Scopus

International Journal of Mechanical Engineering and Technology (IJMET) Volume 5, Issue 2, February 2014, pp. 194 206, Article ID: IJMET_05_02_022 Available online at http://www.iaeme.com/ijmet/issues.asp?jtype=ijmet&vtype=5&itype=2 ISSN Print: 0976-6340 and ISSN Online: 0976-6359 IAEME Publication Scopus Indexed STUDIES ON MASS TRANSFER, DIFFUSION CO-EFFICIENT AND TOTAL RESISTANCES THROUGH ULTRAFILTRATION OF PROTEIN SOLUTION USING LOW CYCLIC DIMER POLY SULFONE (LCD PSF) MEMBRANE B. Chirsabesan, M. Vijay and S. Shanmugananthan Department of Chemical Engineering, Annamalai University, Annamalai Nagar, India *Corresponding Author, sabesan75@gmail.com ABSTRACT Flux decline during ultrafiltration (UF) of protein was quantified by three components, namely, membrane hydraulic, pore plugging, and fouling resistance independently. Flat sheet ultrafiltration membrane was prepared by low cyclic dimer poly sulfone (LCD PSf) dimethyl acetamide (DMAc) and N-N-Dimethyl formamide (DMF) as solvents by phase inversion method. Pore plugging resistances, fouling layer resistance through ultrafiltration of egg albumin (EA) protein solution are calculated by varying pressure. The experiments were conducted in a stirred continuous mode, the range of operating transmembrane pressure drops from 150-400 Kpa at a constant stirring speed. The permeate flux of EA is higher for the membranes prepared by the solvent DMAc than the membrane prepared by solvent DMF. The effect of pore plugging resistance and fouling layer resistance increases were increased with increase of pressures. The decline of permeate flux of EA with increase of pressure is studied with gel polarized model and spiegler kedem (SK) model and compared the all model with experiment data. Keywords: Ultrafiltration, solvents, Protein solution, concentration polarization model, Pore plugging, fouling layer resistance Cite this Article: B. Chirsabesan, M. Vijay and S. Shanmugananthan, Studies on mass transfer, diffusion co-efficient and total resistances through ultrafiltration of protein solution using low cyclic dimer poly sulfone (LCD PSf) membrane, International Journal of Mechanical Engineering and Technology, 5(2), 2014, pp. 194 206. http://www.iaeme.com/ijmet/issues.asp?jtype=ijmet&vtype=5&itype=2 http://www.iaeme.com/ijmet/index.asp 194 editor@iaeme.com

Studies on mass transfer, diffusion co-efficient and total resistances through ultrafiltration of protein solution using low cyclic dimer poly sulfone (LCD PSf) membrane 1. INTRODUCTION Ultrafiltration (UF) is a membrane process capable of retaining solutes as small as 1000 daltons, while passing solvent and smaller solutes. By convention, UF is distinguished from reverse osmosis in that UF does not retain species for which bulk solution osmotic pressure is significant, and distinguished from microfiltration m that UF does exhibit some retention for soluble macromolecules regardless of pore size. The applications of UF are limited to systems where the solutes to be separated have more than 10-fold difference in molecular weight. In such cases, molecular size is the sole criteria for separation. However, it is possible to separate solutes having comparable molecular weights by adequately manipulating the parameters such as ph, ionic strength, and applied pressure.the membrane is prepared by poly sulfone as poly sulfone are used from nanofiltration, ultrafiltration and micro filtration and porous support layer of reverse osmosis membrane, non-pours membrane for use in gas separation, Tolerate to a wide range of ph. Poly sulfone has high compaction resistance, recommending its use under high pressures, It is also stable in aqueous acids and bases and many non-polar solvents, Chemically stability is also very high thermal stable, Mechanical strength is high for poly sulfone membranes. The phase separation method is a convenient and versatile micro fabrication technique for porous membrane with a broad spectrum of polymers [1]. A typical membrane casting solution contains approximately 20 wt% of dissolved polymer. This solution is cast onto a moving drum or paper web, and the cast film is precipitated by immersion in a water bath. The water precipitates the top surface of the cast film rapidly, forming an extremely dense, selective skin. This skin slows down the entry of water into the underlying polymer solution, which precipitates much more slowly, forming a more porous substructure [2]. Depending on the polymer, the casting solution, and other parameters, the dense skin varies from 0.1 to 1.0 μm in thickness. Ultra filtration is a rate governed separation process in which pressure is the main driving force. The feed solution containing macro-molecular solutes is introduced into a membrane separator where solvent and certain solutes pass through a semi permeable membrane which is subsequently collected as ultra-filtrate. Various models are proposed to analyze and predict the flux decline behavior during filtration of macromolecular solutions [3]. All of them can be classified in three broad categories namely (1) Osmotic pressure model, (2) Gel polarized layer resistance, (3) Resistance in series model. According resistance in series model, the flux decline is due to the combined effects of irreversible membrane fouling and reversible membrane fouling (concentration polarization) over the membrane surface in addition to the membrane resistance [4]. In gel polarization model, the major resistance offered to solvent flux is resistance of the gel layer over the membrane surface. On the other hand, in osmotic pressure model flux decline is mainly due to the decrease in the effective transmembrane pressure drop due to buildup of osmotic pressure at the membrane-solution interface[5]. In most of the industrial applications, the flux decline during ultra-filtration is the cumulative effect of several mechanisms, including adsorption of solutes on the membrane surface, pore plugging, concentration polarization, etc. Degree of pore plugging is mainly governed by the relative size of the solute and membrane pore as well as the operating conditions. Fouling caused by the above two types is irreversible in nature and membrane permeability is permanently lost to some extent [6]. Concentration polarization is the accumulation of solute particles over the membrane surface, thereby either forming a growing gel layer or increasing the osmotic pressure at the membrane solution interface, thereby decreasing the effective driving force[7].this type of fouling is reversible in nature and the membrane permeability is regained after following a proper membrane cleaning procedure. Minimization of membrane fouling is essential to make the membrane processes economically competitive [8]. In our present work membranes are prepared by low cyclic http://www.iaeme.com/ijmet/index.asp 195 editor@iaeme.com

B. Chirsabesan, M. Vijay and S. Shanmugananthan dimer polysulfone and dimethyl actimide and Dimethyl formamide as solvents by phase inversion process. The characterization of the membrane is done by permeate flux, Scanning electron microscope (SEM) and x-ray diffraction (XRD).The membrane resistance, pore plugging resistance and fouling layer resistance are calculated and factors effecting the flux decline and concentration polarization is calculated by gel polarized model. Speigler kedem model is used to calculate the permeate flux. Finally the permeate flux is calculated by three models and compared to experimental results. 2. MATERIALS AND METHODS 2.1. Preparation of low cyclic dimer Polysulfone membranes Low cyclic dimer polysulfone membrane was prepared by dissolving 15 wt% of polysulfone in 85wt% of N-N-dimethyl formamide or N-N dimethyl acetamide with continuous stirring until they completely dissolved and homogenous solution is formed. The solution was poured onto a glass plate at room temperature and it was manually casted on a glass plate using casting knife with a gap [9]. The glass plate with the casted film was allowed to evaporate outside for room temperature and immersed in the distilled water at 20-26.After few minutes of initiating the phase inversion, a thin polymeric membrane film was separated out from the glass plate. The polymer membrane composition is shown in Table 1. Membrane Name Polymer composition (wt%) Table 1 composition of polymer membrane Solvents composition (Wt%) Evaporation time(sec) Polymer material Solvents M1 15 85 30 LCD PSf DMF M2 15 85 15 LCD PSf DMF M3 15 85 30 LCD PSf DMAc M4 15 85 3 LCD PSf DMAc M5 15 85 60 LCD PSf DMAc 2.2. Characterization 2.2.1. Membrane hydraulic resistance The flux studies are carried out by permeate at different pressure. Fix the poly sulfone membrane in the UF test cell and take water as feed and find the permeate flux at definite intervals of time. During compaction flux reaches steady state value. Resistance of the membrane is determined at that stage. Permeate flux through membrane can be calculated by equation. To calculate the membrane resistances permeate flux has to be measured at different transmembrane pressures. Membrane resistance is given by equation Where is the Trans membrane pressure (KPa), membrane resistance (KPa m 2 h/l), is permeate flux (l/m 2 h). The membrane resistance is calculated as the permeate flux was plotted against the operating pressure which turned to be straight line from the origin. The slope of the straight line is membrane permeability. 1 2 http://www.iaeme.com/ijmet/index.asp 196 editor@iaeme.com

Studies on mass transfer, diffusion co-efficient and total resistances through ultrafiltration of protein solution using low cyclic dimer poly sulfone (LCD PSf) membrane 2.2.2. Scanning electron microscope The surface structures of PSf membranes are taken by SEM. An excellent advantage of this technique is its ability to image non-conducting materials without special sample preparation, which is essential for the scanning electron microscopy (SEM). SEM measurements were carried out by a Philips XL-40 microscope 2.2.3. X-ray diffration X-ray diffraction is one of the technique that has been used to measure the solvent polymer interaction. The membrane XRD patterns were recorded on a D/max-rB diffractometer. 2.2.4. Preparation of egg albumin solution Aqueous solution of egg albumin was prepared at a concentration of 1000 ppm by dissolving the proteins (0.1 wt.%) individually in phosphate buffer (0.5 M, ph 7.2). The UF cell was filled with protein solution and maintained at 30 C. After ultrafiltration, the permeate solutions of corresponding membranes were collected in graduated tubes and were analyzed for the concentration of protein using UV vis spectrophotometer (Shimadzu, Model UV- 160A) at λmax 280 nm. The percentage protein rejection was calculated from the concentration of protein in the feed and permeates. 3. THEORY 3.1. Pore plugging resistance (R pp ) Using a clean compacted membrane, UF experiment was conducted with feed solution at particular operating conditions for four time durations namely 15, 30, 45, 60 min. During this 15 min of operation, the flux decline profile was noted down by measuring the cumulative weights of the permeate. J 1 w was the value of permeate flux at the end of 15 min. J 1 w can be expressed as Then the cell was dismantled and the membrane was taken out. The membrane was rinsed with distilled water thoroughly so that any deposition on the membrane was washed off.by doing this fouling layer resistance is eliminated. So the pore plugging resistance is given by The value of R m and were already evaluated as described in above sections respectively. With these values, the pore plugging resistance at the end of 15 min was calculated. Similar procedure was followed and the experiments are conducted for three more times namely 30, 45, 60 min at the same stirring speed and operating pressure. 3.2. Fouling layer resistance (R f ) The values of R m, are evaluated from equations (2), (5), (7) respectively the fouling layer resistance at a particular time 15min is given by Thus, at particular operating conditions, growth of the reversible fouling layer resistance with time was estimated. Likewise fouling layer resistance is calculated for remaining times 30min, 45min, and 60min at same operating conditions. 3 4 5 http://www.iaeme.com/ijmet/index.asp 197 editor@iaeme.com

3.3. Gel-Polarized model B. Chirsabesan, M. Vijay and S. Shanmugananthan 3.3.1. Real rejection obtained by concentration polarization model Generally, the solute rejection performance is evaluated through the observed rejection: Where C p and C b are solute concentrations in the permeate and bulk feed side, respectively. However, due to the effect of concentration polarization which decreases the driving force, the solute concentration Cm at the membrane surface is much higher than that in the bulk solution because of the reversible accumulation of the rejected solute when the permeate flux is large. Therefore, the real rejection R T is defined as follows to represent the rejection ability of membranes: 6 Based on the concentration polarization model, the permeate flux, Jv, is expressed as: 7 The mass transfer coefficient appearing in the previous equation can be computed from the well known empirical correlation applicable for stirred cell: ( ) 9 a module geometry dependent constant and can be experimentally determined for a given stirred cell unit as described by Opong and Zydney.The value was determined to be 0.23 The diffusivity was calculated using the following 8 ( ) 10 Here D is in cm 2 s 1 and µ is in Vs is the permeate flux volume In order to determine real rejection R T the above equation (11) can be rearranged as A linear plot of ln1-r obs /R obs vs J v /K can be obtained then real rejection R T is obtained from the intersection point. 3.4. Spiegler Kedem (SK) model This model is also based on irreversible thermodynamics concept, and involves three parameters,. It starts with a local (or differential) equation for fluxes, given by ( ) 12 Putting J A =C p J v ( ) [ ] 13 Integrating the above equation with boundary conditions 11 and X=0 C = C p http://www.iaeme.com/ijmet/index.asp 198 editor@iaeme.com

Studies on mass transfer, diffusion co-efficient and total resistances through ultrafiltration of protein solution using low cyclic dimer poly sulfone (LCD PSf) membrane This on integration gives X= x C = C m Where C p is the permeate concentration P m is the permeability coefficient and C m is gel concentration. 4. RESULTS AND DISCUSSION 4.1. Effect of solvents 4.1.1. Permeation flux of egg albumin protein solution Permeation flux of egg albumin protein studies were carried out in a batch mode. A flat sheet membrane module made from stainless steel was used in all experiments. Effective area of the membrane in the module was 38.5 cm 2. Permeate flux experiments were conducted at a transmembrane pressure and trend is shown in Figure 1. From results, it is concluding that the membrane prepared by PSF-DMAc has the higher permeate flux than the membranes prepared by PSF-DMF. This is due to Membrane prepared by PSF-DMAc has the higher permeate flux than the membrane prepared by PSF-DMF [9]. The membrane prepared by PSF-DMAc has more rejection of permeate than the membranes prepared by the PSF-DMF. The order of solution flux of M 1 was in accordance with that of permeate flux, when a same solute solution was filtrated. 14 Figure 1 Effect of permeate flux on transmembrane pressure 4.1.2. Surface morphology of the membranes The surface morphology of M1, M2, M3,M4, and M5 of the membranes are shown in Figure 2. M 1 is prepared by poly sulfone and DMF and it is evaporated by 30sec in the environment before gelation bath. Membrane M 2 is prepared by poly sulfone and DMF and it is evaporated by 15 s in the environment before gelation bath. Membrane M 3 is prepared by poly sulfone and DMAC and it is evaporated by 30s in the environment before gelation bath. Membrane M 4 is prepared by poly sulfone and DMAC and it is evaporated by 3sec in the environment before gelation bath. Membrane M 5 is prepared by poly sulfone and DMAC and it is http://www.iaeme.com/ijmet/index.asp 199 editor@iaeme.com

B. Chirsabesan, M. Vijay and S. Shanmugananthan evaporated by 60s in the environment before gelation bath. The addition of a suitable solvent into the membrane casting solution shortens the precipitation path and accelerates the coagulation process and thus membranes with a thinner skin layer and a more uniform structure can be obtained. With rapid liquid liquid demixing occurred, the asymmetric membranes owns a porous structure and defect skin layer [10]. On the hand, the dense skin layer with fewer defects on skin surface of asymmetric membranes is formed in the case of delay demixing systems. The weak interaction between solvent and coagulant results a delay demixing and forms a more dense skin layer and porous support sub layer structure [11]. Figure 2 Surface morphology of LCD PSf membrane From Figure 2, it was observed that pure PSf membranes have a dense top surface. When membrane is prepared by DMF to the casting solution, pores appear at the membrane surface in the casting solutions, the largest diameter of the micro pores at the membrane surfaces increases. At the same time, the number pores in the surface of membranes also becomes more. It is known that the cross-sectional structure of asymmetric polymer membrane depends on the solvent. The membranes prepared by DMF have more pores than the membranes prepared by solvent DMAc. The formation of the top layer of these membranes was the result of the combination of the equilibrium thermodynamics and membrane formation kinetics, whereas, the sub layer of these membranes was dominated by the diffusion rate of solvent nonsolvent. It was found that, there was a very good correlation between the permeate fluxes of the M 1 and the final M 5 top layer morphologies. It was known that, the top layer of membrane is responsible for the permeation or rejection, whereas the sub layer of the membrane acts only as a mechanical support [12]. http://www.iaeme.com/ijmet/index.asp 200 editor@iaeme.com

Studies on mass transfer, diffusion co-efficient and total resistances through ultrafiltration of protein solution using low cyclic dimer poly sulfone (LCD PSf) membrane 4.1.3. XRD results The diffract grams of the cast membranes such as PSF /DMAC and PSF/DMF are shown in Figure 3. All the membranes display a broad diffraction feature at 10º to 43º. XRD shows the scattering pattern of polysulfone with the solvent. The morphological change of the five membranes is also correlated to the polymer-solvent interaction. In a polymer solvent system, there are three types of interactions: polymer-polymer, solvent-solvent and polymer-solvent interactions [13]. The change of grain size may be governed mainly by the solvent volatility. Diffraction patterns were obtained to detect the presence of microstructure in the five membranes. Figure 3 XRD patterns of LCD PSf membranes The patterns for all membranes shows broad peaks at 2θ=18.2.We note that the peak position does not depend on the casting solvent. However compared with other membranes the patter of M 5 membrane shows a broadened peak with a decrease of peak intensity. By rapid evaporation of solvent, the grains produced from the polymer dissolved in more volatile solvent grains produced from the polymer dissolved in more volatile solvents can contain large free volume entrapped inside the grains, which causes the formation of large grains. Among the two solvents DMAc has more volatility than DMF. 4.2. EFFECT OF PRESSURE 4.2.1. Effect of concentration polarization on membranes with varying pressure The real rejection was calculated by drawing a graph between 1-R obs /R obs Vs J v /K The intercept of the linear line is real rejection. The obtained value is substituted in the equation that we get the concentration polarization. From the Table 2 the membrane M 1 has more rejection coefficient than the other membranes that is it is possible that membrane M 1 has the rejection of solute in the feed solution is more than the other membranes. The mass transfer of coefficient for the membrane M 1 is high than the other membranes so it is possible of more rejection of solutes. http://www.iaeme.com/ijmet/index.asp 201 editor@iaeme.com

Membrane Type B. Chirsabesan, M. Vijay and S. Shanmugananthan Table 2 Mass transfer coefficient and real rejection Diffusivity coefficient (m2/s) Masstransfer coefficient (m/s) Real rejection M1 1.71 10-16 4.16 10-10 0.98 M2 1.28 10-16 3.43 10-10 0.978 M3 1.13 10-16 3.15 10-10 0.970 M4 1.04 10-16 2.97 10-10 0.817 M5 1.12 10-16 3.13 10-10 0.960 From Figure 4, high pressures gives more flux due to increased driving force, which results in more accumulation of retained solutes and hence increase in gel concentration. Permeate flux increases with increase in operating pressure because of higher driving force applying on membrane surface. With time permeate flux was found to decline rapidly, then gradually and eventually it becomes asymptotic with time axis. Particles or solutes larger than the pore size are transported by permeate advection, which leads to increase in their concentration near the membrane surface and to form concentration polarization (CP) layer [14]. Near the membrane surface in the Concentration polarization layer, diffusive transport of particles can be considered which is likely to be met in boundary layer of the membrane. The membrane M 4 has the high concentration polarization than the other membranes. Figure 4 Effect of concentration polarizations on membranes with varying pressure At 250 kpa pressure the concentration polarization is 60 kg/m 3 for M 3 membrane which is interacting with M 4 as both are made of same solvent DMAc as rendering some pores to be ineffective for further filtration and the other is internal blocking, in which a solute molecule gets trapped inside the tortuous path of the pore. 4.2.2. Comparison of Pore plugging resistance with different pressure for the membrane prepared by PSF- DMF and PSF-DMAc The permeate flux is collected for membrane prepared at different pressures at constant stirring speed. From Figure 5, it is shown that experimentally calculated values of Rp decreases with increase of pressure. High pressures gives more flux due to increased driving force, which results in more accumulation of retained solutes and hence increase in gel concentration. Permeate flux increases with increase in operating pressure because of higher driving force applying on membrane surface [15]. The pore plugging resistance is decreased with increase of pressure this is due to as increase in pressure the force on the membrane surface also increases which leads to more retention of solutes is possible. As increase in http://www.iaeme.com/ijmet/index.asp 202 editor@iaeme.com

Studies on mass transfer, diffusion co-efficient and total resistances through ultrafiltration of protein solution using low cyclic dimer poly sulfone (LCD PSf) membrane pressure the clogging of solutes in the pores of the membrane is decreases. Pore plugging resistance M 1 is higher than the other membranes. The pore blocking may take place as one is surface blocking, in which pore opening gets blocked due to obstruction from solute molecules. Figure 5 Effect of concentration polarizations on membranes with varying pressure 4.2.3. Comparison of fouling layer resistance with different pressure for the membrane prepared by PSF- DMF and PSF-DMAc. Figure 6, indicates that the fouling layer resistance increases with increase of pressure. The fouling layer resistance for the membrane M 1 is 2.88 10 2 KPa m 2 hr/l at pressure 150 KPa and 4.99 10 2 KPa m 2 hr/l at 400 KPa pressure. The fouling layer resistance increases with increase in pressure as it form gel layer on the surface of the membrane. Figure 6 Effect of fouling layer resistance on membranes with varying pressure As the pressure increases the force to solutes ions towards the surface of the membrane increases. The settling of solutes on the surface of the membrane increases as increase of pressure. From the Figure 6 it is observed that the fouling layer resistance is low for the membrane prepared by a DMF than the membrane prepared by DMAc due to its pore structure. http://www.iaeme.com/ijmet/index.asp 203 editor@iaeme.com

B. Chirsabesan, M. Vijay and S. Shanmugananthan 4.2.4. Comparison of total resistance with different pressure for the membrane prepared by PSF- DMF and PSF-DMAc. The total resistance for the each membrane at different pressure is calculated by the summing of the four resistances membrane resistance, adsorption resistance, pore plugging resistance and fouling layer resistance. From the Figure 7 the total resistance decreases with increase of pressure. As the total resistance depend on the membrane resistance, absorption resistance, pore plugging resistance and fouling layer resistance. Figure 7 Effect of total resistance on membranes with varying pressure The pore plugging resistance decrease with increase of pressure as pore blocking is reduced, fouling layer resistance increases with increase of pressure as forming of gel layer is possible by increase of pressure as solutes settle on the surface of membrane. The membrane resistance increases with increase of pressure. So summing of the resistance the total resistance decreases with increase of pressure. It implies that the pore plugging resistance plays a main role in total resistance [16]. From the Figure 7, membrane M 1 has the low resistance than the membrane M 4, M 2, M 3 and M 5.The membrane is prepared by DMAc solvent may be with PSf/DMAc membranes, protein adsorption seems to be more due to hydrophobic or electrostatic interaction which decreases the flux as adsorption of protein on pore wall causes pore narrowing. The variation in morphological structure of the membrane (which includes both top-layer and sub-layer) due different solvents is an important factor in protein transmission and rejection. The flux and rejection of proteins by ultrafiltration membranes can be explained under the concept of protein adsorption and consequent pore narrowing, as a result of both hydrophobic and electrostatic interactions between the membrane surface and the protein molecules. 4.2.5. Comparison of permeate flux J models & J experimental for the membrane prepared by PSF- DMF From the Figure 8, the permeate flux increases with increases of pressure this is due to as increase in pressure accumulation of solutes is more. As pressure increases the blocking of pores in the membrane can be reduced. As the total resistance depends on the membrane resistance, absorption resistance, pore plugging resistance and fouling layer resistance. The pore plugging resistance decrease with increase of pressure as pore blocking is reduced, fouling layer resistance increases with increase of pressure as forming of gel layer is possible by increase of pressure as solutes settle on the surface of membrane [17]. The membrane resistance increases with increase of pressure. http://www.iaeme.com/ijmet/index.asp 204 editor@iaeme.com

Studies on mass transfer, diffusion co-efficient and total resistances through ultrafiltration of protein solution using low cyclic dimer poly sulfone (LCD PSf) membrane Figure 8 comparison of SK, resistance and gel models with experimental data on membranes with varying pressure As the comparison the resistance in series model values is near to the experiential values. The significant contribution of R p in the present dead-end UF process indicated that the membrane used was adequate because the flux could be enhanced by hydrodynamic methods alone. This is one of the advantages in flux decline analysis by resistance-in-series model, which allowed us to know how the flux was improved. Although the bed resistance is proportional to the thickness of the layer, characteristic of the deposited layer such as size and shape of the particles and fraction of void volume in the polarized layer will also affect this flux. 5. CONCLUSIONS In this work, ultrafiltration membranes were prepared with Poly sulfone as a matrix polymer, using DMF and DMAc as solvent. Polysulfone ultrafiltration membranes were successfully prepared with DMAc, DMF as solvent. Characterization is done by permeate flux, SEM and XRD results from that permeate flux for membranes prepared by DMAc high than compared to membranes prepared by solvent DMF. Concentration polarization resistance increases with increase of pressure was calculated by gel polarized model. Pore plugging resistance, fouling layer resistance and total resistances are calculated from resistance in series model. From that pore plugging resistance decreases with increase of pressure. Fouling layer resistance increases with increase of pressure. The total resistance decrease with the increase of pressure. Permeate flux of protein increases with increase in operating pressure because of higher driving force applying on membrane surface. http://www.iaeme.com/ijmet/index.asp 205 editor@iaeme.com

B. Chirsabesan, M. Vijay and S. Shanmugananthan REFERENCES [1] I.C. Kim, H.G. Yun, K.H. Lee, Preparation of asymmetric polyacrylonitrile membrane with small pore size by phase inversion and post-treatment process, Journal Membrane Science. 199 (2002) 75 84. [2] H.Susanto, M. Ulbricht, Characteristics, performance and stability of poly ether sulfone ultra filtration membrane prepared by phase separation method using different macromolecular additive, Journal Membrane Science,327(2009),125-135. [3] P.Rai, C.Rai, G.C.Majumdar, S.Dasgupta, S.De, Resistance in series model for ultrafiltration of mosambi (Citrus sinensis (L.) Osbeck) juice in a stirred continuous mode, Journal Membrane Science, 283 (2006) 116-122. [4] V.K.Jayanti, P.Rai, S.Dasgupta, S.De, Quantification of flux decline and design of ultrafiltration system for calarification of tender coconut water, Journal of Food Processing Engineering, 2008. [5] B.Chakrabraty, A.K.Ghoshal, M.K.Purkait, Preparation, characterization and performance studies of poly sulfone membrane using PVP as an additive, Journal Membrane Science,315 (2008) 36-47. [6] P.K Bhattacharjee, Siddhartha Dutta, Analysis of polarized layer resistance during ultafiltration of PEG-6000: an approach based on filtration theory, Separation and Purification Technology, 33 (2003), 115-126. [7] S.K. Zaidi, A. Kumara, Experimental studies in the dead-end ultrafiltration of dextran: analysis of concentration polarization, Separation and Purification Technology,36, (2004),115 130 [8] P.Rai, G.C.Majumdar, S.Das Gupta,S.De, Understanding ultrafiltration performance with mosambi juice in an unstirred batch cell, Journal of Food Processing Enginerring,28 (2005),166-180. [9] A.Rahimpour, S.S.Madaeni, Polyethersulfone/cellulose acetatephthalane(cap) blend ultra-filtration membrane: preparation, moropology,performance and antifouling properties, Journal Membrane Science, 305(2007)299-235. [10] J.F.Blanco, J.Sublet, Q.T.Nguyen, P.Schaetzel, Formation and morphology studies of different polysulfone- based membrane made by wet phase inversion process, Journal Membrane Science, 283(2006), 27-35. [11] A.Rahimpour, S.S.Madaeni, Effect of type of solvents and non-solvents on morphology and performance of polysulfone and poly ether sulfone ultrafiltration membrane of milk concentration, Polymer Advanced Techonolgy,16,(2005),717. [12] S. Munari, A. Bottino, G. Capannelli, P. Moretti, Membrane morphology and transport properties, Desalination 53 (1985) 11 23. [13] G. Capannelli, F. Vigo, S. Munari, Ultrafiltration membranes characterization methods, Journal Membrane Science (1983) 289 313. [14] D.A. Musale, S.S. Kulkarni, Relative rates of protein transmission through poly(acrylonitrile) based ultrafiltration membranes, Journal Membrane Science 136 (1997) 13 23. [15] K. Kimmerle, H. Strathmann, Analysis of the structure-determining process of phase inversion membranes, Desalination 79 (1990) 283 302. [16] W.Y. Chuang, T.H. Young, W.Y. Chiu, C.Y. Lin, The effect of polymeric additives on the structure and permeability of poly(vinyl alcohol) asymmetric membranes, Polymer 41 (2002) 5633 5641. [17] S.De, J.M.Dias, P.K.Bhattacharya, Short and long term flux decline analysis in ultrafiltration, Chemical Engineering Communication,159,(1997),67-89 http://www.iaeme.com/ijmet/index.asp 206 editor@iaeme.com