Seacrete experiment One
This is an experiment from a few years back where I was learning about Seacrete aka Biorock®. I heard about Seacrete on some documentary and haven't been able to get it out of my mind. I found the primary papers for it and generally reference the following paper when I need to do anything with it. Electrodeposition of Minerals in Sea Water: Experiments and Applications by Wolf H. Hilbertz
I started to think about ways to run this experiment in the ocean but not having a reliable location with permissions I oped for what follows.
Thinking about how I could recreate this experiment in my home, I thought about the reactants and got them.
For the Ca I simply went to the beach and grabbed a bunch of shells. I broke them up a bit and put them near surrounding the anode (+). The cathode(-) was the copper mesh in this experiment. For the water I used seawater that I grabbed while I was at the beach getting shells.
I filled a small glass jar placed the shells and anode in. Then draped the copper mesh over the side and connected the wires.
In the following image you can see the some white precipitate. I assume this is a form of calcium crystal but I have no way of knowing. I figure at some point when It matters I will find a test for it.
A really brief description of what is going on here is that Ca from the shells is dissolving and migrating to the cathode. There it combines with CO2 dissolved in the water to form CaCO3. The CaCO3 accrets on the cathode and forms layers of calcium carbonate. If it were in the ocean it would also have Mg(OH)2
So as you can see there was a small amount of accretion, confirming the basic mechanisms of the seacrete process for me.
I have done three more experiments since then. Ill get into and then talk about what the next one will be.