Have you ever made lemonade? Well, making acetone-butanol-ethanol is kind of like making lemonade.
You start with some lemons (or in this case, a type of corn or cassava), which are sliced up into little pieces. Then you add some sugar and water and stir it all up. After that, you let it sit for a while to allow the flavors to meld together.
With acetone-butanol-ethanol fermentation, scientists take the sliced-up corn or cassava and put it into a container. They add different kinds of bacteria and yeast, which you can think of like the sugar and water in lemonade. These little bacteria and yeast guys eat the corn or cassava and produce different kinds of liquids, just like the lemon juice in lemonade.
One of the liquids they produce is acetone, which is kind of like the sour taste in lemonade. Another liquid is butanol, which is kind of like the sweet taste in lemonade. And finally, there's ethanol, which is kind of like the water in lemonade that makes it less strong.
Scientists use these liquids to make things like fuel or medicines. Just like you can drink lemonade to quench your thirst, these liquids can be used in lots of ways to help people or machines do what they need to do.
So, acetone-butanol-ethanol fermentation is like making lemonade, but instead of lemons, you use corn or cassava and different little bacteria and yeast to create useful liquids that can help humans and machines.