Superior dissertation
Dissertation no. 1
 Dissertation title Lactose recovery from cheese whey using membrane filtration in dairy industry
 Student name Fatemeh Esfandian    Degree Master of Science
 Field of study Chemical Engineering    Publish year 2016
 Supervisor Prof. Ali Asghar Ghoreyshi & Dr. Majid Peyravi    Advisor Prof. M. Jahanshahi
 Abstract Lactose recovery from cheese whey produced in the cheese whey was investigated by ultrafiltration and nanofiltration membrane processes to reuse from its valuable and nutrient compounds and decrease the environmental pollution of cheese whey. Accordingly, the cheese whey prepared from Kalleh dairy factory passed through fabricated ultrafiltration membrane to separate the protein and remove the impurities of whey. In the first part of this project, the ultrafiltration membranes were fabricated and evaluated for cheese whey ultrafiltration. In order to improve the structural parameters and performance of membranes, ultrafiltration membranes were fabricated with different concentration of LiCl (0, 0.1, 0.5, 1 wt %) and finaly 0.5 wt % LiCl was obtained as an optimum concentration. Then, the polysulfone/ sulfonated polyethersulfone blending ultrafiltration membranes were synthesized with blending ratios of 100/0, 50/50, 25/75 and 0/100 at the optimum concentration of LiCl. The results of the performance and fouling behavior in cheese whey filtration indicated that the ultrafiltration membranes comprise both two polymers (polysulfone and sulfonated polyethersulfone) had higher flux and desirable protein rejection. However, the ultrafiltration membrane with polysulfone/ sulfonated polyethersulfone ratio 0/100 showed lowest total resistance (0.61) and the highest rejection (93%). Then, permeate of synthesized ultrafiltration membrane was collected and passed through thin film composite nanofiltration membranes to recover the lactose which the 98% lactose recovery was obtained. Thin film composite membrane was synthesized by interfacial polymerization on sulfonated polyethersulfone sublayer. In order to modify the performance of membrane and change in the structure of top thin layer of composite membrane, 1.5 wt % of two ketone co-solvent (propanone and butanone) was added to organic phase. It was found that adding co-solvent to organic phase caused to change in membrane structure, reduce the roughness and increase the flux. Also, the rejection of these composite membranes didn''t significantly decrease. The highest value of flux related to thin film composite membrane with pororanone and was 10 Kg/m2.h.
 
Dissertation no. 2
 Dissertation title Ligand Immobilization on High Density Nano Porous Kappa Carrageenan Zinc Adsorbents and its Evaluation for Protein Nano Particles Separation
 Student name Nastaran Tavakoli    Degree Master of Science
 Field of study Chemical Engineering-Biotechnology    Publish year 2016
 Supervisor Prof. Mohsen Jahanshahi    Advisor Prof. Ali Asghar Ghoreishi
 Abstract Kappa carrageenan-Zinc (Kc-Zn) chemical structure, with 75-250 μm particle size and 1.7g/ml density as a new expanded bed’s adsorbents matrix, evaluated for macromolecules and biologic nanoparticle adsorption in batch and expanded beds and compared with Streamline industrial adsorbents. Therefore, Tannic acid affinity ligand (TA) used for affinity matrix preparation for both Kc-Zn and Streamline structures. Egg Albumin or OvAlbumin protein and its nanoparticles were used as a target protein model. Effective various parameters such as pH and ionic strength that influence on protein adsorption function were investigated and results were used in experiments. Effects of time and initial concentration were studied in batch system and the highest capacity, 16.32 mg/ml was measured. Also, the pseudo-first-order and second-order kinetic models were used to describe the experimental kinetic results and the highest adsorption percent occurred in the initial 15 minutes. Experimental data was analyzed with Langmuir, Freundlich and Sips isotherm models and well matched with Langmuir model. Expanded bed adsorption breakthrough curves was studied for nanoparticle’s adsorption and effect of some parameters for instance, particle’s siz and feed velocity were assessed. While the velocity was increased, adsorbents showed a decrease in Dynamic binding capacity (DBC) and bigger particle size of adsorbent illustrated similar result too. Also this adsorbents showed better nanoparticles adsorption result in compared to protein’s macromolecules.
 
Dissertation no. 3
 Dissertation title Synthesis and evaluation of nano porous molecularly imprinted polymer “Dicamba herbicide” particles and its application in separation processes
 Student name Tooraj Beyki    Degree Master of Science
 Field of study Chemical Engineering-Biotechnology    Publish year 2016
 Supervisor Dr. Mohamad Javad Asadollahzadeh    Advisor Prof. Mohsen Jahanshahi
 Abstract For the first time, uniform molecularly imprinted polymer (MIP) nanoparticles were successfully synthesized by precipitation polymerization in acetonitrile using dicamba as template, methacrylic acid (MAA) as functional monomer and trimethylolpropane trimethacrylate (TRIM) as cross-linker. The synthesized polymers were characterized by Fourier Transform Infrared (FTIR) spectroscopy and Differential Scanning Calorimetric (DSC). Furthermore, Scanning Electron Microscopy (SEM), Brunauer–Emmett–Teller (BET) analysis were utilized to investigate the morphological characterization. The MIP nanospheres were obtained with the average diameter of 234 nm and the specific surface area of 165.4 m2.g−1. Batch-wise guest binding experiments were carried out to determine the rebinding capacity of the produced MIP nanoparticles towards the template molecule. The binding characteristics were then assessed using Scatchard analysis and some well-known models. A quantitative description of the experimentally measured kinetics isotherms was also obtained using Pseudo 1st-order and Pseudo 2nd-order kinetic models. Finally, competitive binding experiments were carried out to evaluate the selectivity of the imprinted polymer nanoparticles. Compared with the corresponding non-imprinted polymer (NIP), the MIP exhibited higher adsorption capacity and outstanding selectivity towards dicamba in an aqueous solution. Langmuir–Freundlich isotherm best fitted the adsorption equilibrium data of MIP and the kinetics followed a pseudo 1st-order model.
 
Dissertation no. 4
 Dissertation title Membrane bioreactor using membrane-activated carbon hybrid for the treatment of industrial wastewater
 Student name Fatemeh Aghili    Degree Master of Science
 Field of study Chemical Engineering    Publish year 2015
 Supervisor Prof. Ali Asghar Ghoreyshi    Advisor Dr. Ahmad Rahimpour & Dr. Mostafa Rahimnejad
 Abstract Advanced treatment of cheese whey wastewater (CWW) was investigated by hybrid batch mode membrane bioreactor (MBR) and adsorption process. In the first part of this study, the adsorption, activated sludge (AS) and combined activated sludge-adsorption (AS-PAC) processes were evaluated for reducing chemical oxygen demand (COD). The equilibrium and kinetic data for adsorption of organic matters in CWW onto three types of powdered activated carbons (PACs) were described by hybrid Langmuir–Freundlich and pseudo-second order models, respectively. The results indicated that AS-PAC process outperformed individual AS process in different COD concentrations. The most significant result was observed at the 7500 mg/L COD with 4 g/L of the broom sorghum PAC (BSPAC) which could improve COD removal efficiency from 52.3% for AS to 63.8% for AS-PAC process. Also, in this part the bioregeneration of PAC in AS-PAC process was demonstrated by modeling of the dynamic behavior of the AS, adsorption and AS-PAC processes in terms a set of coupled differential equations. In the second part, the BSPAC mixed matrix nano porous polysulfone membranes (MM-BSPAC/PS) were synthesized and characterized by field emission scanning electron microscope, atomic force microscopy and surface area analyzer. Also, the results of the performance and fouling behavior in CWW treatment indicated that the pure water flux and organic matters removal were about 200 L/m2h and 44% for the 0.5% MM-BSPAC/PS, respectively. As a consequence, the irreversible fouling rate (Rir) of the 0.5% MM-BSPAC/PS was about 17%, and it was more than that of other membranes while for this membrane the initial CWW flux was about 95 L/m2h. Also, PAC pre-coat technology was used for enhancing the treatment efficiency. The 30 g/m2 BSPAC coated 0.5% MM-BSPAC/PS could reduce the Rir to 2%. This technology also enhanced the COD removal and CWW flux up to about 95% and 130 L/m2h, respectively. Finally, hybrid batch mode MBR and adsorption process was run for advanced treatment of CWW with 10000 mg/L COD. After coagulation process as the pretreatment, CWW feed to the AS-PAC process and the COD was reduced to 2300 mg/L. Then, for advanced treatment of CWW the 30 g/m2 BSPAC coated MM-BSPAC/PS membrane configuration was used, and at the end of hybrid process, the COD reached to about 130 mg/L.
 
Dissertation no. 5
 Dissertation title Preparation and modification of nanoporous ultrafiltration membranes using funcshionalized chitosan for protein separation
 Student name Samaneh Mokhtari    Degree Master of Science
 Field of study Chemical Engineering    Publish year 2015
 Supervisor Dr. Ahmad Rahimpour    Advisor Dr. Setareh Habibzadeh
 Abstract Due to their excellent chemical resistance, good thermal and mechanical properties, Polysulfone and Polyeyhersulfone membranes are widely used in ultrafiltration. However, in the application involving protein solution, because of the inherent hydrophobic characteristic of the protein, adsorption on the membrane surface and in the pores often cause serious membrane fouling and a rapid decline of permeation flux. The main purpose of this project is surface and morphology modification of polysulfone and polyethersulfone membranes. Thus three kinds of modified membranes were fabricated. In the first, chitosan and polyvinyl alcohol, two highly hydrophilic polymers, were used to modify the hydrophobic polysulfone membranes surface by a dip-coating method. The results of field emission scanning electron microscopy and Fourier transform infrared spectroscopy study of modified membranes indicated that chitosan and polyvinyl alcohol were well coated on polysulfone membrane surface. The results of water contact angle measurement and atomic force microscopy showed that the hydrophilicity and smoothness of polysulfone membranes were significantly improved. Results showed that increasing coating time and concentration cause higher rejection and lower water flux. In addition ultrafiltration performance of unmodified polysulfone membrane improved. UF-P0.2 membrane (modified by 0.2 %wt polyvinyl alcohol and coating time of 2 min) with 205.4 L.m-2.h-1 flux, 96.6% rejection, 81% FRR and 19% Rir and UF-C0.075 membrane (modified by 0.075 %wt chitosan and coating time of 20 sec) with 150.75 L.m-2.h-1 flux, 98.7% rejection, 84% FRR and 16% Rir showed best performance among the fabricated membranes. In second kind, the influences of Salicylate alumoxane nanostructures incorporation to the casting solution were investigated in terms of hydrophilicity, permeation performance, morphology and antifouling properties. Results indicated that by use of 0.1 wt% nanostructures, the pure water flux of the membranes reached to the maximum about 300 L.m-2.h-1. The nanocomposite membrane containing 1 wt.% of Salicylate alumoxane, because of its optimum performance in 143.2 L.m-2.h-1 flux, 99.3% rejection, highest FRR value of 87% and the lowest irreversible fouling resistance value of 13%, was chosen as the best choice. In the third kind, different content of epoxy-functionalized chitosan (ECS) incorporated to the polyethersulfone casting solution. The results of water contact angle measurement showed that the hydrophilicity of polyethersulfone membranes was significantly improved. By addition of 1%wt ECS, BSA flux and rejection were increased from 105.6 to 139.5 L.m-2.h-1 and from 96.2% to 98.8%, respectively. Comparison of modified membranes with unmodified membranes indicated that flux recovery increased to 42% and Rir decreased to 33%, representative good antifouling properties of modified membranes.
 
         
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