Conclusions & Future Recommendations
The sulfite sensor could indicate an increase and decrease in the sulfite concentration with a decrease and increase in output voltage, respectively. When PEG was added, the sulfite sensor and test kit were able to be used to calculate the OTR. Future teams should account for the surface tension of the reaction fluid and bubble size to better characterize the OTR. This could be influencing the difference between the actual OTR from the O2 sensor and the calculated one. Team Chocolate recommends that future teams maintain a larger stock of PEG for future trials and analysis. The sensor data suggests that PEG could be optically and/or chemically altering this reaction, so future teams should work to analyze how PEG interacts and if there are any alternative viscosity modifiers. Teams can also work to obtain more UV-Vis spectra and analyze the reaction kinetics to troubleshoot unexpected outputs of the sulfite sensor. It is also worth suggesting that increasing the pH of the sulfite samples could have an effect on the UV-Vis data. The type of filament used to make the cell should also be taken into consideration to minimize leakage and noise.
Acknowledgements
- Special thanks to Professor Doug Kelley for his immense help in providing the design and drawings for the sulfite sensor as well as helping to 3-D print and assemble it.
- We would like to thank our advisors Professor Mark Juba and Professor David Foster.
- Special thanks to Clair Cunningham, Mason Garlatti, Jeff Lefler, and Zhengfu Huang for their help in the lab as well.
- Thank you to our course instructor Professor Melodie Lawton and TA Jerardo Salgado for your advice and help along the way.
- Finally, thank you to our sponsors Sarah Lanzafame and Kevin Logsdon for allowing us to work on this project.
References
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