(502c) Gotta Keep It Separated: Engineering a Centrifuge From a Simple Salad Spinner

The isolation of compounds of interest from reaction media or source materials presents challenges to the field of chemical engineering that often require creativity and ingenuity to solve. These problems provide high school chemistry educators a unique opportunity to introduce engineering concepts into their classrooms as various separation techniques are also included in many states’ chemistry standards. In this session, an example of a unique engineering challenge posed to Rice University undergraduates will be presented, as well as the novel solution two of those undergraduates devised. In addition, the presentation of this case study to high school chemistry teachers as part of a K-12 outreach program will be discussed, including specific strategies for incorporating both the case study and the engineered product itself into the high school introductory chemistry curriculum. The specific engineering challenge discussed involved finding a way to diagnose anemia without access to electricity that would also be cost-effective and portable.  The solution involved the re-engineering of a simple salad spinner into a cheap centrifuge capable of separating blood samples, thus allowing for the measurement of the ratio of red blood cells to the total volume that is required for the diagnosis of anemia. While the development of this affordable separation technique has obvious benefits for the global health community, it has also had unforeseen benefits for the Houston area high school chemistry community. As it turns out, the same device that can separate blood can also separate precipitates from aqueous solution and is therefore a much more cost-effective means of introducing this separation technique to introductory chemistry students. Presenting centrifugation to students in the context of the engineering challenge for which the salad spinner centrifuge was designed provides students with both a real-world application of this chemistry concept and an example of engineering in practice. Instructions on constructing salad spinner centrifuges will also be provided to session attendees.