Brief project overview
using bacteria to turn styrofoam into biodegradable plastic
The widespread of use of styrofoam and lack of recycling of the material pose a huge waste management problem. In the US, over 3 million tons of polystyrene are produced annually and 2.3 million tons of that end up in a landfill. Only 1% of post-consumer polystyrene waste was recycled in the US in 2000. Thus, an efficient method of recycling styrofoam is needed.
Research problems and goals
Researchers in Dublin have implemented a recycling pathway that involves first, burning polystyrene to styrene oil at 520 degrees Celsius, and then using a special bacterial strain to convert styrene oil to a biodegradable plastic (polyhydroxyalkanoate, or PHA).
Their method is the most efficient so far, but a drawback is that the first step, pyrolysis of polystyrene, creates byproducts such as toluene, though in trace amounts. Toluene is a chemical that, if inhaled in large doses, leads to irreversible brain damage. If we were to use the described process on a large scale -- the recycle the 3 million tons of polystyrene produced in the US, or even the 14 million tons produced annually worldwide -- this process would be too dangerous. The trace amounts of toluene would indeed turn out to be large doses.
We propose a process that degrades polystyrene into an intermediate that does not create such dangerous toxins as byproducts.
Project details and methods
Perhaps a process that could degrade toluene to a harmless substance?
If everything goes to plan, this process could be implemented on a grand scale worldwide and environmental concerns about styrofoam and plastics in landfills would be alleviated.
If nothing goes to plan, we can degrade styrofoam on a small scale in a contained laboratory environment. There should be more focus towards more judicious use of styrofoam and creation of a market for recycled styrofoam.
organic chemists to think of ways to detoxify toluene?