Wednesday, July 1, 2009

Two Roads Diverged in a Lab....

Author: Duncan Peabody

...and I took the one with adsorption isotherm batch experiments. We're at about the half-way point in terms of research and Sam and I are splitting up the work to try to get more accomplished. Sam is going to continue with the Rapid Small Scale Column Tests (RSSCT), which sound very exciting but I think it's false advertisement. The effluent just drips from the columns. There's nothing rapid about it. I am going to start some more batch experiments to produce Adsorption Isotherms. These are even less rapid than the RSSCT but at least they don't offer false hopes of high velocity science. I would tell you what exactly these isotherms are but I don't fully understand it yet. Hopefully Professor Cunningham isn't reading this because he would be very upset to hear that I've already forgotten how to do isotherms. I'll know again soon.

What I do know is that the isotherms will compare the sorption of Arsenic at various pHs, with and without Calcium, and with two different sorbents. The first sorbent is a commercially available Granular Ferric Hydroxide (GFH). The problem is that GFH is quite expensive for a family in a rural village in Bangladesh where Arsenic concentrations are naturally present at dangerous levels. The second sorbent is Iron-Oxide Coated Sand (IOCS) which is a byproduct of some water treatment plants. Usually the IOCS would just be disposed of but it has been found to be a very good sorbent for Arsenic and other heavy metals. The IOCS can be used in a filter for point-of-use drinking water treatment. The research now is focused on how various water quality parameters will affect the effectiveness of the filter. The particular parameter that we are focusing on is Calcium.

We met with Professor Gary Amy today to go over the results we've produced so far. I was kind of nervous to see his reaction because I wasn't sure if our results were any good. He told us that we had just solved the world's Arsenic crisis and we could go home now. Well not exactly but he also didn't tell us to throw away our results and start over so it's almost the same thing. He gave us some good advice on how to proceed with our new experiments. I think we have a good idea of what we will try to accomplish in our remaining time here. Unfortunately we won't be able to accomplish everything that we had planned on at the outset but we will at least have a solid start on this subject for somebody else pick up in the future. I blame the delays on the AAS which seems to have a personal vendetta against us. Or actually it's just broken but I'm going to take it personally.

No comments:

Post a Comment