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Currently, organic compounds are usually synthesised, in batches, by bringing the reactants together dissolved in an organic solvent such as toluene or ethyl acetate, and using heat to cause reaction with the minimisation of unwanted by-products. More recently, new methods of synthesis have been introduced which utilise photochemistry, electrochemistry, microwave technology and/or ultrasound. In the case of ultrasound the energy is usually inputted with ultrasonic transducers, which involves a vibrating probe operating in a similar way to a hi-fi loudspeaker, but this has a number of drawbacks including difficulty in scaling up and being very noisy. We are proposing to overcome all these problems, and more, by utilising a new combination of equipment, which will allow continuous synthesis of compounds at lower temperatures, reduction in energy usage, elimination of organicsolvents, and removal of toxic reagents.At the beginning, a new ultrasonic whistle, which is like a referee's whistle but uses liquids instead of air, and which causes the formation of tiny bubbles that violently implode producing micro areas of high temperature and pressure (called hydrodynamic cavitation), will be used to investigate its potential for reducing energy consumption, eliminating toxic chemicals, etc. (Green Chemistry). Simultaneously, we will model the operation of the whistle using computers, which will then allow refinements to the equipment to increase the amount and efficiency of cavitation. The next phase will entail coupling of the whistle to ultrasonic transducers, which will have the effect of amplifying, massively, the cavitation and will result in a enormous increase in homogenisation, temperature and pressure at the microscopic level, and cause the desired chemical reactions to occur.Normally, organic synthesis is carried out by dissolving the compounds in organic solvents and stirring them with other chemicals either in the same solvent or mixed with water and boiling the reaction for several hours. This is very expensive in terms of heat, inefficient mixing and use of volatile solvents but the new equipment, called a Combined Energy Reactor Train (CERT), will allow continuous processing of reactants without the need for organic solvents or expensive energy input. The CERT will produce highly efficient mixing of organic materials, in water, and the enhanced cavitation will ensure that sufficient local energy is applied to the microscopic bubbles, which contain the compounds and cause them to react.If necessary, any catalysts needed to speed up the reaction will be placed in a tube immediately after the cavitation area and will benefit from the continued mixing and stirring occurring in this region. Also, since the CERT operates at high pressure, air or oxygen can be injected into the reaction to carry out complex oxidations, which are generally difficult to achieve or require toxic chemicals, continuously, at high pressure and moderately low temperatures. Finally, the catalyst bed or the post-cavitational area will be surrounded by electromagnets that have been shown to benefit certain chemical reactions and we will investigate if this phenomenon is observed in our system tooOverall, what is proposed is a completely new concept where a combined energy chemical reaction system with enhanced cavitation capabilities will be designed and built. It will allow chemical reactions to occur continuously, using mainly water as solvent, at low overall temperatures but high pressures as a result of increased bubble implosion and mixing. Even greater benefits will be obtained by injecting high pressure air/oxygen and by applying magnetic fields to the reactor. The equipment will be much more evironmetally friendly (Green) as a result of using less energy, being smaller, eliminating organic solvents and eradicating toxic compounds.S
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