Research Interests:
My research interests are colloidal and interfacial science, Nanotechnolgy, Modeling and Simulation, Polymers , Computational Chemical Engineering and Biotechnology.Projects Undertaken:
1. M.tech Project: "Modeling Nanoparticles Formation in Reverse Micellar Systems"Nanoparticles particles in nanodimensions (at least in one dimension). Because of their high specific surface area, interfacial dominated properties and distinguished electrical and optical properties, have applications in almost all fields of science and technology such as catalysis, microelectronic devices, optical devices, pharmaceuticals etc. In meeting the primary need of various applications, we need to have a precise control over the mean particle size and particle size distribution. One way of preparing these is to precipitate them in swollen reverse
micelles which act as nanoreactors, where the particle size can be controlled by varying the microemulsion composition. Therefore it is necessary to model and simulate the nanoparticles formation in reverse micelles to determine the various parameters required to obtain the targeted size.
There are two kinds of modes of reaction in reverse micelles, one is gas liquid mode of reaction and the other is liquid liquid mode of reaction. In gas-liquid mode of reaction one of the reactant is passed as a gas into the microemulsion containing the other reactant. In liquid-liquid mode of reaction, we have two kinds of additions, one is simple addition in which aqueous solution of one reactant is directly added to the microemulsion containing the other reactant, the other is two microemulsion addition, in which two microemulsion containing one of the reactant each are mixed together to form nanoparticles.Though the precipitation process involves mass transfer, reaction, collision, nucleation and growth of nuclei, analysis of time scales of these processes and considerations gives different models.
As the formation process is stochastic in nature, Monte-Carlo simulation is a natural choice, but it is computationally intensive as the number of micelles is very large. Stochastic population balance models describing the nanoparticles formation and growth in reverse micelles considering the finite nucleation and exchange rates, instantaneous reaction and growth of nuclei, for gas-liquid and liquid-liquid mode have been developed. Though the precipitation process involves mass transfer, reaction, collision, nucleation and growth of nuclei, time scale analysis of these processes and considerations gives different models. The population balance equations describing all possible combinations of state of micelle using fusion fission mechanism have been developed and solved by using the ODE solver LSODE (ODEPACK) and R-K fourth order method in case of liquid-liquid mode of reaction. The effect of various parameters like nucleation rate, water to surfactant molar ratio and collision rate on the particle size distribution and terminal particle size has been investigated. The model predictions show consistent results and qualitatively good agreement with experimental data
CdS and Ag2S nanoparticles have been prepared by simple addition and two microemulsions mixing methods using AOT/heptane/water microemulsion. And the particles were characterized using Transmission Electron Microscopy and UVVIS-Absorption Spectroscopy. And it is observed that the particle size in case of simple addition is larger than in case of two microemulsion addition method.Guide: Prof. Kartic. C. Khilar
(Department of Chemical Engineering, IIT Bombay)2. B.tech Project : "Manufacture of Aniline"
This dealt with different aspects of the processes available for the manufacture of Aniline, viz., selection of a optimal process, material and energy balances and design of distillation column for the seperation of aniline from the other bi-products and unreacted reactants. The cost estimation for the plant and a well sophisticated layout for the plant have been developed.Guide: Prof. M. Venkateshwara Rao
(Department of Chemical Engineering, R. V. R & J. C. College of Engg., Guntur, Andhra Pradesh.)
Seminars Presented:
1. "Additives and Solvents for Polymers in Casting Sunthetic Membranes"Guide: Prof. M . K. Trivedi
(Department of Chemical Engineering, IIT Bombay)2. "Gas Conversion in Fluidized Beds"
Fluidized beds have been found applications in a number of processes involving gas- solid and solid-catalyzed gas phase reactions. Successful processes have included catalytic cracking, acrylonitrile manufacture, ore roasting, polyethylene production, calcination operations and combustion operation of a wide variety of fuels. Recent years have seen a resurgence of interest in fluidized beds operated at high gas velocities in hydrodynamic regimes beyond the slugging regimes. A number of models have been developed for G/S systems, such as packed beds, bubbling fluidized beds (BFB), turbulent fluidized beds (TFB) and circulating fluidized beds (CFB). Advantages of fluidized beds for these operations are the capability of operating with small catalyst particles and hence high effectiveness factors, favorable bed-to-immersed-surface heat transfer coefficients, ability to withdraw and add particulate solids continuously, and the possibility of operation on a very large scale.To
predict the behaviour of a chemical reactor requires information on the stoichiometry, thermodynamics, heat and mass transfer, reaction rates, and lastly, flow or contacting pattern of materials in the reactor. A number of models for various contacting regimes have been developed in literature and these are in well agreement with the experimental results.
The present report gives an overview of models developed for
the prediction of conversion equations for different contact regimes in fluidized bed reactors. The models for contacting regimes for bubbling fluidized beds, turbulent fluidized beds and circulating fluidized beds are presented.Guide: Prof. V. Govardhana Rao
(Department of Chemical Engineering, IIT Bombay)3. "Flow through micro/nano channels"
Guide: Prof. Kartic. C. Khilar
(Department of Chemical Engineering, IIT Bombay)4. "Inventory and Control of Emissions from Biomass and Fossil fuel Combustion"
Guide: Prof. S. P. Mahajan
(Department of Chemical Engineering, IIT Bombay)Imporatant Courses Undertaken During Undergraduation and Post Graduation:
1. Colloidal and Interfacial Science
2. Chemical Process Equipment Design
3. Process Control and Instrumentation
4. Heat and Mass Transfer Operations
5. Optimization
6. Mathematical and Statistical Methods of Chemical
Engineering.
7. Advanced Transport phenomenona
8. Computer Aided Design and Engineering
9. Chemical Reaction Engineering
10. Natural and Synthetic polymers
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