Indian Institute of Technology Madras, India
Title: Neccessity of Accurate and Precise estimation of Homogeneous Surface Diffusion Model parameters for Adsorption process
Biography: Akhil Gopinath
Batch adsorption kinetics based on Homogeneous Surface Diffusion Model (HSDM) for phenol adsorption onto activated carbon is studied. Film Mass transfer coefficient kc and the surface diffusion coefficient DS is estimated by finidng the parameters using which the HSDM simulation gives a concentration profile which has minimum deviation with the experimental concentration time data. The deivation being minimized is the sum of square of error (SSE) between the simulated and experimental concetration-time data. Two of the traditional optimization techniques which are used widely for parameter estimations were used namely, Nelder Meads Simplex algorithm (NMA) and Particle swarm optimization (PSO). kc and DS values for runs with different initial concentrations, Dosages and Agitation were estimated. The variability in the estimated parameters and their implications were analysed. Error surfaces were plotted by varying kc and DS values and plotting them against the corresponding SSE. Error surface analysis supported the need of approaching global minimum as the surface plotted had multiple optimum values. time of operation required for 95% reduction of solute concetration in liquid from its initial concentration estimated based on parameters was studied. It was seen clearly that though the parameters fit the experimental data in an appreciable manner on observation, even the minutest fluctuation in them resulted in increasing the time of operation by upto 100% in some cases.