Continuous Flow Microreactor

Independent researchers studying chemical processes face a challenge due to its lack of equipment for small scale experiments. In industry, the resources are available to run chemical reactions on a large scale in huge tanks with essentially unlimited resources. To efficiently and consistently induce chemical reactions on a small scale, a continuous flow microreactor is a simple solution that can provide this desired effect. The main concept that proves a microreactor to be an excellent method for running small-scale reactions is the turbulence generated in small diameter pathways and bends that achieve a good mix of reactants. In addition, if a volatile reaction is desired this reduces the risk involved as the amount of reactants in use at any time in continuous flow microreactor is significantly low compared to batch production.

The design of the micro reactor is relatively simple with an inlet leading into a narrow winding pathway up until the outlet. The two main concerns around the design are visibility of the reaction and rapid prototyping to enable quick turnaround for varying experiments. To address visibility, the microreactor is made by adding polydimethylsiloxane (PDMS) to molds of the top and bottom half of the design. To achieve rapid prototyping, the main mode of production implements 3D printing of the molds.

The production of a microreactor begins with the design of the negative of the top and bottom half of it using CAD software. Then, the designs are exported into a file that can be imported into a 3D printer. Once the molds are produced the next step is mixing a 1:10 ratio of curing agent and PDMS monomers to enable the PDMS to set. After this, the molds and PDMS are baked until it is set.

The original design was intended for a specific experiment, but the scope of this project scales far beyond the initial experiment. The rapid prototyping nature of 3D printing can allow for unique reactors for different experiments or quick redesigns if a flaw is found post production. Also, many modifications can be made to the original design to extend its usefulness. These could include parallel pathways to run either cold or hot fluid through the system to create a temperature change to enhance the reaction or adding multiple inlets to combine multiple fluids rather than coating the pathway in reactant as is done in the initial experiment.