Catalysis

Standardized Stirring for Small Scale Surveys

J Scott McIndoe University of Victoria

Abstract

Stirring rates in heterogeneous catalytic reactions have an effect on reaction rates. When conducting small-scale surveys using a single central stir plate, reaction vessels in different positions experience slightly different levels and patterns of agitation. We probed this effect by running the same reaction 40 times, varying the stir rate (fast/slow) and the vial position using two 3D printed vial holders. We found variability of conversion (measured mass spectrometrically) to be approximately two times higher for vials placed at different distances, but the effect was relatively small and could be minimized by using a high stir rate. For those experimenters wishing to completely eliminate differential stirring as a cause for variation in results, the 3D printed circular array we designed is recommended over a conventional rectangular array.

Content

Thumbnail image of Manuscript for standardized stirring_IO1_SM1.pdf
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Supplementary material

Thumbnail image of SI for standardized stirring_IO1.pdf
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SI for standardized stirring IO1
Thumbnail image of Manuscript for standardized stirring_IO1_SM1.docx
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Manuscript for standardized stirring IO1 SM1
Thumbnail image of SI for standardized stirring_IO1.docx
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SI for standardized stirring IO1
Thumbnail image of 10circular.stl
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10circular
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slowlinear
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slowround
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6circular