Week Recap 6/19

Hello again,

I’m here to share some stories from the week. This week was a bit better. I got to do some more lab work, watch others in their projects and work on some issues with my own project.

Monochloramine mixture setup

On Monday, I ended up helping my mentor make monochloramine for 3 jar tests which had micro-pollutants. The purpose for doing so, is to measure how many disinfection-by-products were made after adding the monochloramine. I’m not sure what the differences in the waters were because this was for a different project of hers. She just asked for my help. We had made the monochloramine with some chemicals, all of which I don’t remember. I generally remember the process. We heated up a substance on a hotplate with a stir bar in there. Then, we had to make a dilution of 2000x from one substance to another. Once that was completed, we had 250mL of that new compound which we added to the substance we heated up on the hot plate. This was a slow process because crystallization could of taken place had we mixed them too fast. The way we did this, was by a very long, and thin column tube. It had a small stream that was probably 1mm

The tube used to slowly stir in the solution

thick after opening the bore. It took maybe 15 minutes to completely mix the solution. After that, we had to let it sit in the dark for about an hour. By that time, the jar tests were finished, so all we had to do was filter out the micro-pollutants using some weird system that might have a name I don’t know. That took about 4 hours to do because as the micro-pollutants were

Filtration setup. There is a large feed glass on top of the flask where the contaminated water goes. It passes over a membrane and filter and pours into the flask. A pump was used to suck the water through

getting caught on the filter, the flow rate started to decrease significantly. In total, there were 3 different jar tests that needed filtration. For each jar test, which were inside the giant rectangle jars in the left image, we needed to have 520mL of filtered water. So, it took all those hours to filter out a total of 1560mL of the contaminated water. Put it into new amber jars and then clean everything up. The fun part about cleaning up was the acid bath. All of the equipment which had contact micro-pollutants needed to be cleaned in nitric acid. Simply, that acid would kill any bacteria or microbiological contaminates from the jar tests. On top of all my lab coat, gloves and eye wear, I had to put on thick rubber gloves, and a face shield. That was still not enough, the acid bath was under a fume hood which I could only slide up partially. Bending down to get in there was fun and annoying, but after the bath of all the glasses. I had to rinse them with some DI water at least 10 times each. Just to ensure they were clean. The smell of the acid was strong though, that’s for sure. After that, I had to go through to our stock area, and look once again for all of the chemicals we will be using to make the NSF53 challenge water. That took another hour because I had to look through the 100 plus there was. Only finding 6 of the 10. The following day, I went back and found 1 more. Then my mentor had to go ask around for the other 3 chemicals. In the upcoming week, we will be actually making the water and running our column tests, HOPEFULLY. Monday was a busy day in the lab, but I don’t regret it.

The following day was a bit more fun, but didn’t last too long. We now had time to cryogrind the

A nice blue color

ZimmermanMedia. Here is an image of the ZimmermanMedia which was synthesized at Yale University.

The cryogrinder with the liquid nitrogen tank on the floor in the back

Apparently, it takes about 3 week to actually make this stuff, which is why we don’t have much, but ASU is the only one with the compound right now. Anyways, the purpose for cryogrinding the media is because it is a very porous medium and we need those pores in order to adsorb the arsenic from the water. If we were to grind this material traditionally with a mortar and pestle, we would collapse those and break them down. What a cryogrinder does, is use liquid nitrogen and freeze the media to about -200 degrees celcius so that way the structure is frozen. The atoms are moving very slowly and instead of smashing the media, its more like breaking it so the structures just split. We need to maintain that porous structure. I’ve attached the link to download the video (which is sideways for some reason). It’s only a few seconds long of the actually cryogrinder, inside and the enjoyable fog coming off. It’s not in action because it can be rather loud, but it was after we finished using it. IMG_0769[1]-1ucq29j Following the cryogrinding, the media was a beautiful color. I actually don’t want to use it, I kind of just want to keep it

Cryogrinded ZimmermanMedia

and look at it. It’s a very fine powder and comes together smoothly. Perhaps I’ll upload a video of what it looks like in motion around the vial. I like how it went from a dark blue to that light baby-bluish-purplish color. This is only about 3/4 of one vile of raw media that we used. There will probably be more that will have to be grinded in the future. At that point, I will have some more images.

The rest of the week, Wednesday and Thursday, I was trying to figure out how to measure absorption of UV light, into our solid media. We were going to be using polyethylene tubing as a column, and the nice blue media would be inside the column. Apparently, it’s more reactive and efficient if UV light is shining on it. However, from what we’ve found polyethylene tubing absorbs most of the UV light and is not efficient to use in our tests. We haven’t found a new column, but instead, I think we will be using borosilicate lab glassware tubing for our media. I believe some windows are made of this same glass, but those have added materials to block UV light. The glass is lab special, and I don’t think it will absorb the light too much. It should pass through no issue, as with most glassware in the lab. Therefore, the amount of light hitting the media will be high, and that’s all that matters. As long as the media is absorbing light, there will be no issue.

Friday, is always the fun day of the week. I usually have 3 to 4 meetings every Friday, which are all from the different groups under my PI. Two of the meetings are NEWT meetings. One other is for nanotechnology in general, and other chemistry… things. The last meeting is organics, and that is for other people dealing with nanotechnology and the organic side of either growing crops or other parts of life. I’m not entirely sure because I haven’t attended those every week. Even when I do, I have minimal idea what they are talking about. The NEWT meetings are usually research updates from all the students and post docs in my PI’s lab. How far they are, what they did over the last week, what they have left to do, how their papers are coming along, etc.

For now, that was my week, I know it’s long, but I hope somebody takes the time to read it. I think it’s cool, but even if you don’t, I don’t care, because I read it and I liked it. I’ll comment on it on my own and start a conversation with myself.

Until next week,

-Chris