Nanofibrous membranes due to their high separation efficiency have been the focus of researchers in the field of membrane filtration in recent years. The membrane filtration efficiency is directly related to the geometry of the membrane. Predicting the fluidflow behavior of the nanofibrous membrane will be important from the point investigating the effect of geometrical properties on the filtration efficiency. The aim of the thesis is concentratio n and velocity prediction along nanofibrous membrane. In order to achive this goal, the study is devided in two sectio modeling and experimental. The modeling section includes pore size modelling, web generation and concentration prediction. At first a model was made to pridict pore size and distribution and was validated by experimental tests. This model yields more accurate results than previous models by considering the 3,4 and 5 - sided pores and obtaining the hydraulic radius. Then web was generated b y this model using java codes. The virtual nanofibrous web has thickness, diameter of nanofibers and porosity percentage in the range of conventional numbers. In addition the input data is independence from experimental data and the possibility variance of nanofibers diameter , high speed and low volume of program the benefits of athe virtual nanofibrous web generation program. Subsequently, 3D dimensional nanofibrous membranes were recalled in the software and the fluid flow behavior of the membrane dur ing the deadend continous filtration was predicted using the integrated mass transfer equations in CFD. The proposed model does not require a correction index Because is near to real sample. The validation was by a porous cube in size of real mode. adsorp tion and desorption coefficient and maximum adsorption capacity was obtained by the fitness of model and experimental resul ts. Mesh independency was done. The adsorption capacity of 0.006 mol/m2 nanofibrous web was much higher than the 0.0013 mol/m2 of por ous model without porous model. This suggests that the nanofibrous model yields better results. Finally the influence of porosity, fibre diameter and membrane thickness was investigated on the average outlet concentration . At the experimental section, in o rder to validate the obtained model, PEI/PES membrane was fabricated by electrospinning. This soluble web was crosslinked by glutharaldehyde so that a water - stable membrane was achieved. The amount of glutharaldehyde was optimezed by several tests like wei ghing, absorbtion. The water - soluble membrane was used for nitrat anion adsorption. The adsorption was done in static and dynamic modes. The results of the characterization by SEM,TEM,BET and FTIR showed the membrane has suitable characters for an affinity membrane. Nanofibrous web with 33 .wt% total polymer and 0.71 % volumetric glutharaldehyde was completely water - satble. different isotherm and adsorption kinetic models were also studied. Results showed good agreement of the data with Langmuir isotherm mo del and it was found that adsorption follows pseudo second - order kinetics model. The maximum adsorption capacity of the web was 29 mg/g under condition that was higher than similar membranes in the litrature.