Development and Application of 3D Printed ... - ACS Publications

Feb 19, 2018 - In this study, the versatile use of 3D printing in chemical engineering ... the designed reactors were printed and ready to test in a m...
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Article Cite This: J. Chem. Educ. XXXX, XXX, XXX−XXX

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Development and Application of 3D Printed Mesoreactors in Chemical Engineering Education Tahseen Tabassum,† Marija Iloska,† Daniel Scuereb,† Noriko Taira,† Chongguang Jin,† Vladimir Zaitsev,† Fara Afshar,‡ and Taejin Kim*,† †

Materials Science and Chemical Engineering Department, Stony Brook University, Stony Brook, New York 11794, United States Department of Academic Affairs, Suffolk Community College, Brentwood, New York 11717, United States



S Supporting Information *

ABSTRACT: 3D printing technology has an enormous potential to apply to chemical engineering education. In this paper, we describe several designs of 3D printed mesoreactors (Y-shape, T-shape, and Long channel shape) using the following steps: reactor sketching, CAD modeling, and reactor printing. With a focus on continuous plug flow mesoreactors (PFRs, i.d. = 2 mm), fluid mixing phenomena were explored by using a passive mixing method. The small channel of mesoreactors facilitates the stability of a laminar flow in the system at low Reynolds number. With changes in flow rates (0.2 and 4.0 mL/ min) and channel geometry (0° and 90° outlet angle), fluid mixing was controlled. Our results provided that 3D printed mesoreactors can be possibly used in teaching fluid dynamics, chemical kinetics, and reaction engineering, which are main courses of the chemical engineering undergraduate program. Furthermore, the cost of mesoreactor printing was suitable ( 1 mm) are used for small scale experimentations, discoveries of new materials at a laboratory level, and preparations of processes for scale up, while sparing a significant amount of chemicals.21 Especially, microreactor applications have grown in the pharmaceutical industry for organic synthesis and speeding up drug discovery.21 Since micro- and mesoreactors have a large specific interfacial area (liquid−liquid or liquid−solid), short molecular diffusion distance, and short residence time, they facilitate precise control of reactive factors in highly selective reactions that are challenging for conventional reactors. The combined microreactor and 3D printing technology have immense potential especially for chemical engineering education (undergraduate and graduate program) with several advantages: minimal requirement of chemicals, hands-on lab experiences, and competitive low experiment cost. Shirk et al. used this combination to develop a protocol that enables the fabrication of microreactors by 3D printing a template using acrylonitrile butadiene styrene (ABS), and then casting with polydimethylsiloxane (PDMS) adhered to glass.22 The authors demonstrated both a single and double casting technique with shrinking silicone, and provided clear images to examine the minimized extent of imperfections in the channels. In this study, the versatile use of 3D printing in chemical engineering education was demonstrated in two sections. The



GENERAL METHODOLOGY AutoDesk Inventor Pro 2017 and Simplify3D software were used to design and create models, and the PowerSpec Ultra 3D printer was used to print the reactors. AutoDesk Inventor is computer-aided software for designing and creating 3D digital prototypes for visualization and simulation of products, and it is free for universities and colleges. Simplify3D is slicing software which can convert 3D CAD models into G-Code that can be understood by the 3D printer. It costs $149.00 USD, and runs on Windows, Mac OS X, and Linux operating systems. Detailed descriptions of AutoCAD software, equipment, and 3D printing techniques are provided in the Supporting Information. In brief, tentative sketches of the microreactors were made. Using AutoDesk Inventor, CAD files for several parts of the reactor (e.g., inlet and outlet) were generated and saved as an .iam file format. The .iam files were used to assemble all parts and were saved as .ipt format. The .ipt format files were converted to .stl format ones which were transferred to the Simplify3D software for reactor printing. With an average print speed of 15 mm/s, the designed reactors were printed and ready to test in a matter of hours. The typical cost of materials for a reactor was 4000, and is in a transition region for 2000 < Re < 4000.28 Typically, microreactors exhibit laminar flows due to the small channel and relatively low flow rate.29 The calculated Re value is considerably below 2000, indicating a laminar flow. Despite that, the 90° reactor for 4.0 mL/min shows a fully mixed outlet stream which implies that the right angle enhances the mixing between the two fluids, without altering the value of the Reynolds number under the conditions employed in our work. The effect of reactor geometry on fluid mixing, especially at very low Re, has been widely investigated using microreactors.29−34 Nimafar et al. studied mixing efficiency between three different types of microreactors: O-type, T-type, and split and recombination micromixer (SAR) at low Reynolds number in the range 0.083−4.166.29 The authors concluded that the SAR reactor provides a much more effective mixing at a low Re compared to those of O- and T-type. Although our reactor design is much simpler than the SAR one, it proved that mixing efficiency can be simply improved with different fluid mixing angles. It has been reported that a passive mixing reactor has an advantage over an active one due to the simple design.20 Chew et al. reported the influence of reactor design on chaotic advection at very low Re,