When I was working, there was interest in "biopolyethylene", PE is the most common form of plastic. The deal was to make cellulosic ethanol and then ethyene and then PE. It would have the same properties as PE, but not come from petroleum sources. OK, fine. But cellulosic ethanol has flopped, I THOUGHT it might work in Brazil from bagasse as that already gets collected, but that largely flopped as well.
This was to be part of our program to source PE from something other than petroleum and be "green". Flop flop flop.
And it was largely predictable. It's akin to making fuel from algae, it has a number of very obvious major issues. But it makes nice PR.
