Guide: Prof. F. Durst, CEO, FMP Technology and Professor Emeritus, FAU Erlangen-Nuremberg
Investigated the stability of downward-falling liquid film flows which find application in curtain-coating mode to coat thin liquid films on plane substrates.
Film thickness, velocity and mass flow rate of a downward facing liquid film were measured, starting close to the exit of a slot die producing the liquid film. The die was constructed to produce a “slot-guided” fluid flow from the slot inlet down to the exit, resulting in a parabolic velocity profile, before it turns into the falling film.
The stability of the falling film was tested with and without side-guides. A “super-stability” was observed that allowed “stable films” to be produced at mass flow rates below the Brown- Taylor criterion. Quantified the minimum mass flow rate for producing “stable curtains” by steadily lowering the flow rate up to verge of instability.
Developed an analytical explanation for the “super-stability” of the liquid film that the surface tension forces between the side guides and the fluid provide the extra stability to the curtain.
Hofmeister Effect of Ions on Polymer-surfactant Complexation (May ’12 - Jul ’12)
Hindustan Unilever Ltd. R&D Center, Bangalore, India
Guide: Dr. S. J. Suresh, Global R&D Director, Superior Cleaning Systems, Unilever
Hofmeister effect of ions involves salting-out and salting-in of inter-polymer complexes (IPCs), however little is known on the effect of salts on polymer-surfactant complexes (PSCs). The study investigated complexation characteristics of a PSC of Poly-acrylic Acid and Brij35 in presence of NaSCN, NaCl, NaI and Na2SO4 respectively.
Determined the solubility points based on turbidity measurements to study phase behavior of the PSC in presence of salts. Plotted solubility charts for the PSC to determine the degree of salting-out and salting-in in the presence of respective salts.
Studied the effects of water re-structuring on solubility and hydrophobicity of the PSC. Employed fluorescence spectroscopy to study the changes in hydrophobicity of the micro- environment of PSC caused by the electrolyte ions.
Biodiesel Production from Waste Vegetable Oil (May ’11 - Apr ’12)
Project Biosynth, Department of Chemical Engineering, IIT Bombay
Guide: Prof. Sanjay Mahajani, IIT Bombay
With the vision of meeting the campus energy needs, this project was initiated by a team of students to design and install a self-sustained biodiesel plant, with a capacity of 250 L/batch.
R&D - Planned R&D works to find optimum oil-methanol ratio in transesterification step to maximize conversion of triglycerides to biodiesel.
Plant Commissioning - Participated in the commissioning of Biodiesel Plant set up in the institute campus. Performed hydro and pressure-test of equipments and pipelines in the plant.
First Plant Run - Conducted the first biodiesel plant run in the campus in February 2012. First batch successfully produced 150 liters of biodiesel from waste vegetable oil.
Life Cycle Assessment - Prepared a detailed LCA report for comparison of biodiesel and diesel, presented at Industrial Green Chemistry World 2011 in Mumbai.