Ferrofluid Testing

Ferrofluid is a unique substance that no members of our group had ever dealt with. We conducted a variety of experiments this past week to gain a better understanding of the substance and study its interactions with other materials.  Shown below is a photolog of the experiments done to test the various interactions.

Microplastics

The ferrofluid interacted with microplastic as predicted. We began the experiment by using a 2 mm sieve to separate microplastics from the larger shreds of plastic created using the chopper. We then collected and placed the microplastics into a glass cylinder filled with 150 ml of tap water. Three drops of ferrofluid were then pipetted into the cylinder and stirred to achieve even distribution. The ferrofluid immediately began to envelop the microplastics. In water, ferrofluid is attracted to microplastics due to the nonpolar properties of both. We were then able to extract the ferrofluid covered microplastics using a magnetic stir bar. Since one of the main components of ferrofluid is oil, most of the substance remained at the surface of the water and was easily removed from the water using the magnet. 

Soap & Water

For this project, we plan to use Dawn dish soap and water to wash the plastic shards produced by our chopper. We wanted to see how the ferrofluid would react with soap before we implemented this plan, so we created soapy water in a cylinder and introduced several drops of ferrofluid. As forementioned, one of the key components of ferrofluid is oil, which breaks down when it encounters soap and water. The ferrofluid did exactly that. Once broken down the leftover ferrofluid particles were easily removed with the magnet.

Container

We conducted several small-scale experiments to determine which type of container material would be best for the ferrofluid implementation portion of our project. The first small container we tried was made of type 5 plastic. We did not expect this material to work well and we were correct. The ferrofluid seemed to cling to the container in a similar way it clung to the microplastics and was difficult to remove from the water using a magnet. The second container we tried was made of metal. We expected the ferrofluid to be attracted to the sides of the container due to its magnetic properties. Surprisingly, the ferrofluid had little to no reaction when it came in contact with the metal container and was easily extracted with magnetic stir bar. Lastly, we once again used a glass cylinder. The ferrofluid had no reaction to the cylinder and after stirring the magnet in the water several times, the water was clear and contained no visible remnants of ferrofluid.

To achieve the best possible outcome for this project we need to purchase a stronger magnet to thoroughly extract the ferrofluid from water. We also need to order a metal or glass container to ensure that unintended interactions do not occur during microplastic removal.