Temperature controlled interval contact design for ultrasound assisted liquid–liquid extraction

Abstract

This work aims at constructing a design which integrates direct contact method (or a solid contact interface) with temperature control for chemical process applications. To realise this integration a two-step approach is proposed. Firstly temperature control is introduced by is achieved by suspending the tubing in a temperature controlled and sonicated liquid medium (indirect contact) and secondly the direct contact elements are introduced at regular intervals along the tubing. This design which incorporates both direct and indirect approaches of ultrasound transfer is termed the hybrid contact reactor. Two feasible configurations, open and closed intervals, were assessed. The hybrid reactors performed better than the indirect contact reactor (20 to 27 % higher yield) for lower residence times of < 45 s and similar for higher residence times. Comparing the two hybrid designs, even though their performance was similar the closed interval gave more stable and distinct yields. The latter design was scaled up to 10 times in volume with a 2 mm ID tube design. This design showed a relative performance similar to the interval contact design which gave the highest yields thus far for the same operating conditions.

Pulsed ultrasound for temperature control and clogging prevention in micro-reactors

“…These collapses lead to the formation of hot spots of high temperature (>5000 K) and high pressure (>1000 atm). Such a temperature increase impacts on different scales: for chemical reactions, it is important to have an accurate temperature control, especially when working with temperature sensitive reactants, as it can impact the quality and yield of the reaction [8]. This increase in temperature can also affect the gas solubility and vapor pressure, which will reduce the cavitation activity [9,10].…”

“…For instance, Dalvi and Yadav [12] used a jacketed batch reactor with an immersed ultrasonic horn for curcumin antisolvent precipitation. John et al developed a temperature controlled interval contact reactor [8], by combining a small-scale ultrasonic bath with an ultrasonic interval contact reactor [13,14]. In this work, we establish an ultrasound application strategy to achieve both the external and internal temperature control of the micro-fluidic device without the need for additional cooling.…”

Beyond electrolysis: old challenges and new concepts of electricity-driven chemical reactors

“…The interval contact can further include a temperature control medium flowing in the gap between the reaction tube and the aluminium plate. 93 Systems targeting thermal energy supply Microwave reactors. The research on the application of microwave (and radiofrequency) heating to chemical reactions started in the 1980s with the pioneering works by Gedye and co-workers.…”

Ultrasound‐assisted emerging technologies for chemical processes

“…To bring about an effective combination of the ultrasound with a microchannel, a temperature controlled interval contact reactor was designed in the ALTEREGO project (Fig. , left) . This design makes use of a solid interface at regular interval between microchannel tubing and ultrasound transducer for effective transfer of power and a liquid medium flowing between the solid interfaces for proper control of the temperature of the reaction mass …”

“…1, left). 8 This design makes use of a solid interface at regular interval between microchannel tubing and ultrasound transducer for effective transfer of power and a liquid medium flowing between the solid interfaces for proper control of the temperature of the reaction mass. 9 This design was proved to be effective using a model reactive extraction process the hydrolysis of p-nitrophenyl acetate.…”