Hayley Johnston's blog

This week I finished up my final round of batch experiments with a chemical called 1,3-dinitrobenzene. It was pretty quick and easy, I finished it, plus a couple extra TNT experiments within the week. DNB is faster than everything except for TNT. 

This is a graph of the final product of my experiments: 

This week I spent a lot of time working on DNAN to try to figure out what is going on at the end of the reaction. 

I can't believe that we have already passed week seven! Just a few more weeks and I will be back at Lewis & Clark starting my junior year. This week I started running experiments with 2,4-dinitroanisole, or DNAN for short. DNAN is currently being used as an explosive compound in ammunitions production, and so it is of high interest in this project. We expected DNAN to have a slightly faster half life than that of DNT, but slower than TNT, and that turned out to be true, so it was easy to get 3-4 different reaction vials going in one day.

This week I ran tests on 2,4-dinitrotoluene or DNT, the precursor to TNT. The only difference is that TNT has one more nitro group in the 6 position. Ali and I decided that this would be a good compound to test because it is very similar to TNT, and since TNT behaved kind of weirdly in the data that I have already collected, we wanted to see if a similar compound would do the same thing. As it turns out, the DNT did not behave in the same way as the TNT!

On Monday of week 5, Dr. Tratnyek, Ali and I had a meeting to discuss the results I obtained from my TNT trials. I ran six different trials two times each with six different concentrations of iron porphyrin, and I made a graph of the observed rate constant (k-observed) versus the concentration of iron porphyrin ([FeP] (M)).

This week was a short week because of the Fourth of July! I hope everyone had a great holiday. This week I finished up completely with the second round of TNT trials, we did two trials because the data on the first trials was slightly off. TNT has a much shorter half-life in iron porphyrin than NB does, so irregularities in the method, or preparation of the samples has a much bigger effect on the resulting data. However, I am getting better and more accurate at the experimentation processes.

As I am continuing to talk to Ali and Paul, I am beginning to understand more about the significance of the research that I am doing. The reason I am doing these trials to figure out the reaction rates of nitro compounds is because of concern about environmental contamination by munitions compounds (especially near manufacturing facilities and military training sites). One way to help prevent some of this contamination is to use compounds that are more environmentally friendly—less toxic, less likely to accumulate, and they will persist in the environment for shorter periods of time.

As I head into the last day of week two, I can’t even believe how much I have done in just one week! This week I started three experiments with differing concentrations of iron porphyrin and I started tracking the reaction rate. The data that I was getting is close to what we expect it to be, but there was an anomaly on the curve that made us think about what might have caused it. From there we realized that our glove box (a box filled with nitrogen and helium instead of oxygen) actually had really high levels of oxygen in it.

What a crazy first week here at CMOP! I am working in Dr. Paul Tratnyek’s lab under the guidance of my mentor Ali Salter-Blanc. They are in the middle of a four-year project and I just got plopped right into the middle of it all. The phase of the project that we are currently working on, is determining reaction rates of nitro reduction reactions.