Determining the Ion exchange capacities (IECs) of certain membranes are what our work has focused on during this second week. We made a few membranes by mixing certain amounts of Polyvinyl Alcohol (PVA) and sulfosuccinic acid (SSA) and leaving the resulting solutions in an oven for 24 hours.  We made a total of 12 membranes and determined their IECs. The IEC of a membrane is important because it affects how well the membrane can do its job of preventing ion backflow during Membrane Capacitive Deionization (MCDI). We have not carried out any MCDI trials yet for the membranes. We will do that in the upcoming weeks.

8 of the membranes in their vials

The lab has also ordered the parts for a flow coater device and those should be arriving in the next few weeks. Once we have the parts we will have to assemble the flow coater in order to use it to coat our electrodes with the membranes for MCDI trials.

Until next week

T

In just a few days, I will be starting a 7 week internship at Rice University organized by the NEWT. I will be working with Dr. Verduzco to perform membrane capacitive deionization (MCDI) to carry out energy efficient water desalination. The initial stages of the internship will be focused on developing a flow coater device. A flow coater device will enable us to coat a thin film of the polymer we wish to deionize onto the electrodes in our MCDI cell.

In flow coating, the polymer solution is held beneath a blade by capillary forces. Eventually, as a result of the edges of the solvent in the solution vaporizing, the volume of our polymer solution will decrease. Due to this, frictional drag will cause part of our solution to escape underneath the blade and set itself apart in the form of a wet film. This wet film then dries, which allows to coat the electrodes with it.

To build the flow coater device, we will need a blade that is to be placed atop the polymer. Glass slides are often chosen to act as blades due to their inexpensiveness. We will also need a three axis rotating stage to hold our blade and allow us to control its angle of motion.

I would like to thank Dr. Veronica Leautaud for all that she has done for the 2016 NEWT interns. I am fortunate to have the opportunity to work with brilliant engineers who strive to make the world more energy efficient and am excited to begin this new project of designing a flow coater device with Dr. Verduzco’s team.

I look forward to blogging again soon.