Procedure:
Washing and treatment of the cigarette filters:
Cut and remove the paper surrounding the filter;
Measure the mass of the filters and put them in 4 beakers of 1000mL;
Fill each beaker with 1000mL of deionized water;
Stir with a stirring rod for 5 minutes. After that, remove the water to a new recipient;
Repeat steps 3 and 4 one more time for all of the beakers;
6. Put 800mL of water in the beakers and put them in a heating plate at 50ºC for 60 minutes;
7. Stir with a stirring rod;
8. Remove the water from the beakers;
9. Put 125mL of ethanol 96% in each beaker;
10. Remove the ethanol to a new recipient;
11. Repeat step 9;
12. After a week, remove the ethanol from each beaker to a new recipient;
13. Put the filters in small glass containers so they can go to the greenhouse at 60ºC until they are dry;
Creation of the mould for the glasses frames:
Take a piece of modeling clay and start modeling it into a shape resembling what you want to print;
Take one of the temples from the glasses frames you are going to use to make the mould and put it in the modeling clay and apply pressure;
Remove the temple;
Repeat step 1, 2 and 3 for the other temple and for the frame front.
Creation of the glasses frames made of cigarette filters:
Put the cigarette filters in a small beaker;
Measure their mass;
Add 10% of the cigarette filters' mass of glycerol into the beaker;
Add acetone in small quantities until the cigarette filters are dissolved;
Put the final mixture in tubes to centrifuge;
Pour the mixture into the mould and let the acetone evaporate;
7. Remove the glasses frames from the mould;
8. With a spatula remove the clay that stayed attached to the frames;
9. Attach small hinges with hot glue to the frames;
10. Attach the temples to the frame front with hot glue.
Notes:
First try at making the mould:
The first mould that was made was of plaster. However, when we tried to remove the frame we used to do this, it broke completely. Also, when the mixture was poured into the mould, it was completely absorbed which made it impossible to remove this part of the frame from it. This way, there was a need to find another material to make the mould, specifically modeling clay.
Plaster mould
Analysis:
Morphological characterization:
Using SEM, we obtained images of the clean filter and the plastic film obtained after recycling the cigarette butts. These images show that the cellulose acetate in the cigarette filters is in a fibers form about 30 micrometers in diameter and after the procedure it is in a form of polymeric film.
SEM of the clean filter
SEM of the plastic film
Infrared (IR) analysis:
IV analyses were performed on both samples, clean filter and recycled plastic film. It is possible to observe an overlap of the obtained spectra.
Overlapping spectra of IV
Discussion/Conclusion:
The slightly darker color of the prototype, we concluded it was due to the fact that the filters stayed too long in the greenhouse, which led them to getting a bit burned and it showed in the prototype. We conclude that it is necessary to pay more attention to the time when the filters are in the greenhouse and we should remove them as soon as they dry, when they have a white and soft appearance.
The SEM allows us to conclude that the plastic obtained is in the form of polymeric film as expected.
Also, through the overlap of the IV spectram form both samples, it was possible to conclude they were chemically equal. When searched in the spectram library it was possible to conclude that both samples were cellulose acetate.
This way, it was proved it was possible to make glasses frames without toxins from filters of recuperated cigarrete butts, giving this residue a new life.
What we can do in the future:
It would be necessary to improve the process of making the glasses frames so that it is more robust and functional, being able to withstand lenses. Perhaps this could be achieved with a partnership with a company specialized in the manufacture of glasses frames, using a more efficient elaboration technique. On the other hand, the prototype that was obtained can be dissolved in acetone so, by establishing the partnership, it would be possible to figure out how to stop the action of this substance.
The cigarette butts were washed with water and ethanol. The water washing solution, which should have dissolved nicotine, can be used as an insecticide in organic farming. The reuse of this waste is a good example of the circular economy and also contributes to the sustainability of this project, but we would have to make analysis to make sure there are no heavy metals in its composition, because, if there are, it can't be put in the soil. However, the ethanol washing solution may contain some toxic pollutants resulting from the burning of tobacco, so it should be deposited safely.
In the future, we have to optimise the procedure so it can be made in a big scale, making it industrially viable. Also, in a future development it would be interesting to investigate the possibility of of making the cigarette butts biodegradable and to evaluate the possibility of degrading the plastic from the glasses frames, possibly using organisms that consume this material, after the intended use.