@article { ISI:000258442800009, title = {CFD simulation of gas-liquid flows in a reactor stirred by dual rushton turbines}, journal = {International Journal of Chemical Reactor Engineering}, volume = {6}, year = {2008}, month = {JAN}, pages = {Article No. A60}, publisher = {BERKELEY ELECTRONIC PRESS}, type = {Article}, address = {2809 TELEGRAPH AVENUE, STE 202, BERKELEY, CA 94705 USA}, abstract = {

In the present work, we have simulated gas-liquid flows in a tall stirred reactor equipped with dual Rushton turbines. A two fluid model along with the standard k-epsilon turbulence model and modified drag coefficient, (proposed by Khopkar \& Ranade, 2006) accounting for the effect of bulk turbulence, was used to simulate the dispersed gas-liquid flow in a stirred reactor. The multiple reference frames (MRF) approach was used to simulate impeller rotation in a fully baffled reactor. The computational model was mapped on to a commercial solver FLUENT 6.2 (of Fluent Inc. USA). The model was used to simulate three distinct flow regimes in a gas-liquid stirred reactor: L33-VC (lower impeller-upper impeller), S33-VC and VC-VC. The model predictions were compared with the published experimental data of Bombac \& Zun (2000). The predicted results show good agreement with the experimental data for all the three flow regimes. The computational model presented in this work would be useful for simulating different flow regimes in a gas-liquid stirred vessel.

}, keywords = {computational fluid dynamics, dual Rushton turbine, Flow regimes, gas hold-up distribution, stirred reactor}, issn = {1542-6580}, author = {Kasat, Gopal R. and Pandit, Aniruddha B. and Ranade, V. V.} } @article { ISI:000346322200038, title = {Crystal shape evolution using polyhedral population balance}, journal = {Industrial \& Engineering Chemistry Research}, volume = {53}, number = {49}, year = {2014}, month = {DEC}, pages = {18966-18974}, publisher = {AMER CHEMICAL SOC}, type = {Article}, address = {1155 16TH ST, NW, WASHINGTON, DC 20036 USA}, abstract = {

Research on crystal morphology covers shape evolution of single crystal and evolution of the size and shape distribution of populations of crystals. The population balance models have been used for the single or multiple dimensions for predicting the evolution of crystal size distributions (CSDs). More often than not these models do not consider the change in solute concentration due to disappearance/appearance of the crystal faces and therefore compromise rigorous mass balance. The present work focuses on the methodology for the morphological evolution of crystal shape using a polyhedral population balance model. This methodology is based on the morphodrome which illustrates the shapes of crystals at various operating conditions. gPROMS software (PSE, UK) along with Microsoft Excel is used to devise the framework for predicting the crystal shape evolution. The developed approach and models can be implemented for various crystallization systems and will be useful for simulating crystal shape evolutions.

}, issn = {0888-5885}, doi = {10.1021/ie501039c}, author = {Shaikh, Latif J. and Ranade, Vivek V. and Pandit, Aniruddha B.} } @article { ISI:000363917000038, title = {Generic framework for crystallization processes using the population balance model and its applicability}, journal = {Industrial \& Engineering Chemistry Research}, volume = {54}, number = {42}, year = {2015}, month = {OCT}, pages = {10539-10548}, publisher = {AMER CHEMICAL SOC}, address = {1155 16TH ST, NW, WASHINGTON, DC 20036 USA}, abstract = {

A generic modeling framework for batch cooling crystallization processes has been developed to understand the crystallization process from operational and modeling point of view. The generic framework for crystallization process modeling incorporates the characteristic dimensions of crystals and polymorphic transformation, as well as the hydrodynamic mixing effects in the crystallizer. This Polyhedral Polymorphic Multizonal Population Balance (PPMPBM) model considers bottom-up and top-down approaches for specific systems with specific targets. The PPMPBM framework allows switching between complex and simple models to study different crystallization systems with different scenarios and combination thereof. This framework uses gPROMS software (PSE, UK) and the Microsoft Excel front-end, along with the Polytope module in Matlab, to predict the crystal size and shape evolution as well as supersaturation profiles inside the crystallizer, which can be implemented for various crystallization systems.

}, issn = {0888-5885}, doi = {10.1021/acs.iecr.5b01421}, author = {Shaikh, Latif J. and Bari, Atul H. and Ranade, Vivek V. and Pandit, Aniruddha B.} } @article { ISI:000373419900016, title = {Intensification of degradation of methomyl (carbamate group pesticide) by using the combination of ultrasonic cavitation and process intensifying additives}, journal = {Ultrasonics Sonochemistry}, volume = {31}, year = {2016}, month = {JUL}, pages = {135-142}, publisher = {ELSEVIER SCIENCE BV}, address = {PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS}, abstract = {

In the present work, the degradation of methomyl has been carried out by using the ultrasound cavitation (US) and its combination with H2O2, Fenton and photo-Fenton process. The study of effect of operating pH and ultrasound power density has indicated that maximum extent of degradation of 28.57\% could be obtained at the optimal pH of 2.5 and power density of 0.155 W/mL. Application of US in combination with H2O2, Fenton and photo-Fenton process has further accelerated the rate of degradation of methomyl with complete degradation of methomyl in 27 min, 18 min and 9 min respectively. Mineralization study has proved that a combination of US and photo -Fenton process is the most effective process with maximum extent of mineralization of 78.8\%. Comparison of energy efficiency and cost effectiveness of various processes has indicated that the electrical cost of 79892.34 Rs./m(3) for ultrasonic degradation of methomyl has drastically reduced to 2277.00 Rs./m(3), 1518.00 Rs./m(3) and 807.58 Rs./m(3) by using US in combination with H2O2, Fenton and photo-Fenton process respectively. The cost analysis has also indicated that the combination of US and photo-Fenton process is the most energy efficient and cost effective process. (C) 2015 Elsevier B.V. All rights reserved.

}, keywords = {Fenton, Hydrogen peroxide, Methomyl, Photo-Fenton, Synergistic coefficient, Ultrasound cavitation}, issn = {1350-4177}, doi = {10.1016/j.ultsonch.2015.12.015}, author = {Raut-Jadhav, Sunita and Pinjari, Dipak V. and Saini, Daulat R. and Sonawane, Shirish H. and Pandit, Aniruddha B.} } @article { ISI:000375507300036, title = {Treatment of the pesticide industry effluent using hydrodynamic cavitation and its combination with process intensifying additives (H2O2 and ozone)}, journal = {Chemical Engineering Journal}, volume = {295}, year = {2016}, month = {JUL}, pages = {326-335}, publisher = {ELSEVIER SCIENCE SA}, address = {PO BOX 564, 1001 LAUSANNE, SWITZERLAND}, abstract = {

Hydrodynamic cavitation (HC) and its combination with H2O2 and ozone have been applied in the present work for the treatment of industrial pesticide effluent. Initially, the effect of dilution of the effluent on the efficacy of hydrodynamic cavitation has been studied using circular venturi as a cavitator. Although an increase in the extent of dilution has not shown any beneficial effect on the actual moles of pollutant degraded, hybrid processes have been studied using 1:5 dilution due to very high TDS content of the effluent. Treatment of the industrial pesticide effluent using HC + ozone (3 gbh) process has demonstrated that the biodegradability index (BI) of the effluent increases from 0.123 to 0.324 after 2 h of operation. The rate of COD and TOC reduction has also increased by many folds by using HC in combination with ozone. In addition this, the treatment of industrial pesticide effluent using HC + H2O2 has also indicated that the rate of COD and TOC reduction increases significantly by using HC in combination with various loadings of H2O2. The study of interference of added H2O2 on the COD analysis has exhibited that the COD equivalence is 0.441 mg/L for 1 mg/L of H2O2. The energy efficiency and operating cost of various hybrid processes have been compared based on the cavitational yield and the cost of electricity. The combined process of HC and H2O2 has observed to be the most cost-effective one due to its higher cavitational yield and lower power consumption. (C) 2016 Elsevier B.V. All rights reserved.

}, keywords = {Biodegradability index, Hydrodynamic cavitation, Hydrogen peroxide, Industrial pesticide effluent, Ozone, Venturi}, issn = {1385-8947}, doi = {10.1016/j.cej.2016.03.019}, author = {Raut-Jadhav, Sunita and Badve, Mandar P. and Pinjari, Dipak V. and Saini, Daulat R. and Sonawane, Shirish H. and Pandit, Aniruddha B.} } @article {45537, title = {Improved efficiency of DSSC using combustion synthesized TiO2}, journal = {Materials Research Bulletin}, volume = {109}, year = {2019}, month = {JAN}, pages = {222-226}, type = {Article}, abstract = {

Combustion synthesis method is an economic, one step and an effective method for the synthesis of nanomaterials. In this work, titanium dioxide nanoparticles were synthesized by combustion method. The synthesized material was characterized by XRD, SEM and BET. Dye sensitized solar cell was fabricated using the synthesized material and its performance was compared with the solar cell fabricated using commercial TiO2. In order to evaluate the photovoltaic performance of DSSCs, photocurrent density to photovoltage (J-V) characteristic and electrochemical impedance spectroscopy (EIS) measurements were carried out. The DSSC fabricated using combustion synthesized and commercial TiO2 exhibited a power conversion efficiency of 6.11\% and 6.62\%, respectively. Combustion synthesized TiO2 which displayed similar efficiency to that of commercial material is least studied in the literature for solar cell applications.

}, keywords = {Combustion synthesis, Dye sensitized solar cell, TiO2}, issn = {0025-5408}, doi = {10.1016/j.materresbull.2018.09.044}, author = {Umale, Sanjivani and Sudhakar, V. and Sontakke, Sharad M. and Krishnamoorthy, K. and Pandit, Aniruddha B.} }