Changing Reaction Scales
Often screening reactions are carried out at one scale, and once you establish the reaction conditions to give you the product you require, you may wish to run the reaction to give more product. Even with the same reaction mixture, changes in the fluid volume and electrode area and spacing will alter the resistance (and therefore the link between the potential difference and current) with the degree of mixing influencing the transport of material between electrodes
Within a given reactor geometry, such as the ElectroReact, scale-up (or scale-down) is within two similar geometry reactors - e.g. from a larger to smaller bottle. Since by working with the ElectroReact the gap between electrodes remains constant, we are left with estimating the appropriate electrical conditions and time of reaction. The information below will give a starting point to help you with this. It uses the concept of resistivity to allow you to set new parameters.
When you change scale, you might want to run under the same potential difference as the original experiment, or the same current as the original experiment. Since the resistance between the two electrodes will change (for example as a result of a bigger wetted electrode surface area), you generally can only match one of these parameters. This in turn influences the time required for the reaction.
The modeller below has been setup for ElectroReact, with a controlled electrode spacing of 6mm and a fixed depth below the electrodes where the mixer sits. It also assumes the mixing to be constant, which is a reasonable assumption in the ElectroReact, but might not be going between very different equipment. Key outputs are the new current (if you want to retain the original potential difference) or the new potential difference (if you want to retain the original current). The reaction time will also change - here it gives you the scaling factor to multiply the original reaction time with (2 would indicate you run the reaction in your new arrangement twice as long, 0.3 would indicate you run it for 30% of the original value). The modeller does assume certain geometric parameters within the ElectroReact including the dead-volume below the electrodes and stirrer bar volume. You may want to download the spreadsheet and explore the physics under the scaling tab a little further.