The Colour Society presented the Prof N.R.Kamath Memorial Lecture on 21st September 2018 at K.Venkataraman Auditorium, ICT Mumbai. The guest lecturer was Professor Dr.V.G.Gaikar is a Distinguished Alumnus of ICT, Chair of Chemical Engineering and maiden Vice Chancellor of Dr.Bhabha Saheb Ambedkar Technological University, Lonere who presented “Intensification of Processes and Systems”.
Prof P.Mahanwar convened the meeting and Dr.Tipanna Melkeri, President welcomed the distinguished audience. Mr.K.N.Aras spoke about Prof N.R.Kamath and expounded about his track record of scoring 100% marks in chemistry at St.Xavier College, research work in London during World War, career with UDCT and IIT-B, mastery for lecture on any subject, interaction with students and mentoring people like J.M.Nadkarni, C.J.Bhumkar, Ravi Marphatia et al. he was the founder member of the Colour Society, and headed brainstorm panel discussions; He was associated with Bombay Paints and development of paint industry in India, with traits like clarity and expression with relaxed mind for corrective action, contingency plan etc.
Prog Gaikar obtained PhD in chemical engineering in 1986 with several awards to his credit, published 200 papers, 2 books, 3 book chapters and 8 patents, delivered lectures in various conferences, coordinator for TEQIP etc. His specialisation is process intensification, thermochemical conversion of biomass to chemicals derived by molecular modelling and innovation practices.
Paying tribute to the best teacher who left legacy behind with illustrious teachers like Prof M.M.Sharma, Prof Gaikar with 30 years teaching experience looked forward to return to ICT equipped with science and technology and said that teachers should inspire students to take up challenging problems to solve. In 1856, Sir W.H.Perkin as an 18 year old student attempted to synthesise quinine from coal tar (cheap and byproduct of coal) and accidentally found Mauve and became an entrepreneur for science based industry for the purple colour used then by the Queen for Royal Home Guards. He could do with basic knowledge of chemistry and without engineering. He invented his reactors, vats, stirrers, pulleys etc. Equipment in manufacturing industry centuries ago were showcased. Are we going to continue with them or change the way we conduct the reactions, he asked. Look at the opportunity to make change, build business and create jobs are the need of the hour.
- Introspection of processes and reaction system: Are we getting limited by our own experience, isn't there a way we change to conduct the experiments? and build reactors that can simplify the production processes.
- General process considerations: when a product is formed in pure form, we don't need large funds. Process intensification starts with selectivity and reactivity. Intensify reactions and make them faster, simpler and cheaper so that rectors can be put into small space. Heat reactor to required temperature for reactants to react and observe how the reaction takes place and overall reaction rate and the time taken for the batch. Reaction kinetics and physical processes like mixing, diffusion, conductivity are the limitations arise from the process and equipment used.
- Limitations of chemical reactions: Mixing time, heat transfer, pressure, temperature of operations, scale up using bigger reactors. Large operations hold ups/safety. Understanding basics of physics and chemistry to manipulate the parameters. Mixing, temperature and uneven distribution leads to side reactions. With that design reaction environment it gives phase of reaction and every reactant molecule. Desirable attributes of reaction time, throughput and corresponding quality of product.
- Process intensification – An academic perspective: Process integration and continuous flow systems. Drive the reactions to its limits of physics and chemistry. From academic curiosity to practical applications, it is important for enhancing the competitiveness of our industries. Chemical industries are slow in adopting new techniques, processes, systems, innovations and communications, unit integration like reactive distillation etc. Production of azo dye from initial process of coupling, completed in just few minutes. Time control on quality of the final product. This process is becoming more popular with fine chemical industry. Can condensation reactions be made continuous and for continuous processing, you must have control on the way you conduct it. Other possibilities are new agents such as ionic liquids; super critical carbon dioxide and adding some organic solvents in limited quantity.
- High Concentration processing practically without solvent: Increase the temperature, pressure and consequently reaction time is 2-3 hours in pharmaceutical industry. It has a direct effect on the size of the reactor. Small reactors maintain same production. High processing reactions are also on the anvil. Micro reactors and flow reactors in pharmaceutical industry are dependent on flow chemistry.
- New reaction pathways: Synthesis of Vitamin D using laser light. Sequestration or conversion of carbon dioxide into useful products. They built a team for making products which are not available in the market and brought down the cost.
- Microwave oven: Exposure of something yields product. No synthesis or production is possible here. How to design the cavity? Maximum generation of electrical field that ultimately leads to heating, chemicals that can be built and finance application and eventually reach to a design, insights into building microwave cavities, simulation of temperature reached by water flowing through the reactor and actual measurements. Reactions complete in 5 minutes except in some rare cases residence time to 10-15 minutes.
- Microwave flow reactor and stirred reactor: Change are made for the students thinking differently and can handle process. Give them a challenge to work on, problems not tried before. These reactors are used for a variety of reactions. The reaction is over in 5 minutes. Continuous process enzyme reactor. Control the flow rates and residence time. Hydroxy-methyl furfural from sucrose separating into glucose and fructose in variable timings.
- Ultrasound reactors in chemical processing: Understanding design calculation with changes brought resulting in building 2 new reactors e.g. tubular reactive system and stirred vessels.
- Flow reactor for enzyme catalysed reactor where enzymes are located inside besides chemical modifications.
- Continuous enzyme reactor.
- Continuous inversion of sucrose.
- Fast reactors in flow reactions: High temperature reactions like pyrolysis used for concentrated waste treatment. Experimental set up for complete degradation of organic waste at 1300°C to carbon dioxide and water. In pyrolysis, breaking down organic molecules avoids carbon deposition. It was identified that 19 simultaneous reactions and 34 components were involved in the process with reaction time of one second. Knowing what was formed as a part of the process, they build the reaction network like packing process in a refinery. The set of reactions were put into conventional chemical engineering equations and solved with set of equations.
- Mathematic model of pyrolytic reaction network: They are the first one to show that they can take up reaction and analyse using mathematical modelling.
- Simulation results against experimental data values. Process intensification: They apply extreme conditions; high temperatures warrants machines which are capable of handling large forces. It must be designed with innovative materials.
- Caveats: Risk vs. Efficiency. They are working with people in the areas of RF (Radio Frequency), inductive, microwave and solid-state electronic heating systems. Microwave curing of paint and polymer processing. Scale up depends upon manipulating in micronizing environment of the systems. The objective was to bring down the cost.
Prof Gaikar concluded speaking about challenges. Large scale applications with electronics, is easier with fine chemicals industry. Range of applicability to all kinds of reactions. Availability is taken care of. Operational issues are reliability. Can we develop innovative products? Take younger generation towards innovation and this can form basis for them if they want to go for start-ups and become players.
Dr.K.S.Murthy, Pidilite Industries Ltd