Hey errbody,
Hope you all had a nice long weekend and Independence Day! I came back Wednesday to some beautiful data from the experiment we left running Friday night. I spent the day sort of going over all of the data for our .22 um membrane and estimating at what concentration an initial flux decline is seen and setting up to run the same experiment for the following day. We ran the same experiment (1L volume, 1.5X concentration, .22um pore size) until the flux declined by half and analyzed whether the flux declined at the same concentration as last time. It did,
This is a 3D view of the surface (bird’s eye view) of our membrane from our longest-running experiment. Look at that crystal formation! ITS BEAUTIFUL. THIS IS MY FAVORITE PHOTO.
within ~0.1 difference. Today, we did the exact same, but with the intent of stopping it just minutes after a flux decline is observed. The experiment was running longer than I had expected, and I got a little paranoid that the decline had already begun. I ended up stopping it a little too early, which is fine because we were going to run an experiment and stop it just before the decline anyway. So, Monday I plan to run the same experiment once again and this time actually let it run until just after the decline.
Also, we’re currently learning and experimenting with the OCT (optical coherence tomography) microscope. Tomography is a technique for displaying a representation of a cross section through a solid object using X-rays or ultrasound. I believe ours uses X-rays. We’ve been sticking our fouled membrane samples under it and taking shots of the scaling we can see on the membrane. This is the microscope we’ll be using with the windowed cell, IF IT EVER ACTUALLY GETS DONE. Haha. Anyway, the microscope takes some practice before you’re comfortable with it, but is super fun. Here’s some shots:
Here is a 3D cross-sectional view of the surface of the same membrane. I like this one because if you look closely, you can see what I believe to be salt formation inside the pores (spikes jutting out on the underside of the surface). Also you can see some mega scaling on that sucker (i.e. all of those bumps).
Here’s sort of a 3D cross-section of a huge salt deposit I found (see the mountain?). Neato.
Compare the other photos to our unfouled membrane, ran only with DI water. Nice and smooth, yo.
I like the 3D models! I want to do some fun stuff like that. Hopefully you finish you setting up your windowed cell and get to run your microscope.
Nice pictures! I’m glad to see your project is moving along, and thank you for being such a consistent blogger!