Week Seven (May 15th, 2018 - May 21st, 2018)

      In this week's lab, the group tackled many different things. Amy and Stefan focused on finding alternative solutions that could attempt to rectify our issue with the metal solution not being completely filtered by our design. Down below, I will share those alternatives. Laurynn and Oliva focused on creating a more cohesive prototype design while retesting the organic, metal, and bacteria solutions, and also brainstorming ways to create a better flow rate. In the first table, this shows all of the qualitative tests that were done with different materials, in order to filter out the blue copper solution.

	Material	Mass (g)	Result
Trial 1	Pistachio Shells	66.3	FAIL
Trial 2	Crushed Pist. Shells	85	FAIL
Trial 3	Pistachio Nuts	74.2	FAIL
Trial 4	Cucumber	91.7	FAIL
Trial 5	Crushed Cucumber	42.1	FAIL
Trial 6	Sawdust	55.3	FAIL

The Pistachio Shell's qualitative test

      Interesting enough, when the sawdust and the blue copper solution were combined, it made a yellowish green mixture that turned out to be chromium. A chemical substance that is really dangerous to consume, so not the best solution for filtration. While these qualitative tests were going on, Laurynn and Olivia were more focused on perfecting the group's prototype and retesting all of the solutions. 

Olivia preparing our prototype

        The two began to use a similar orientation of the materials for the first trial run. In the first prototype, they decided to mix the sand, activated charcoal, and the chunky charcoal altogether. They decided to increase the sand from last time, in order to prevent some charcoal residue from leaking into the filtered water. 

      Within the first trial, we were able to filter out both the organic and bacteria solutions, however, we still faced a problem with the metal solution. The flow rate was still the same from last week because we maintained relatively the same measurements, with the exception of the sand. In the second trial, Olivia and I figured that we do multiple layers. So, the base layer was comprised of 92.2 g of sand, 1.0 g of activated charcoal and 7.5 g of the regular or chunky charcoal. Then the chunky charcoal had a layer of its own above that measuring in at 8.4 g. Then, the final layer was comprised of 70.5 g of sand. 

	Sand	Act. Charcoal	R. Char
Trial 1	91	1.2	15.4
Trial 2	162.7	1	15.9

      The ordering method that we used in the second trial worked better universally with all of the solutions, opposed to the first trial. Next week, we will finally hone in and have a permanent model of our filtration device.