Water From Wood

Water, water everywhere and not a drop to drink…

This is Sandra Tsing Loh with the Loh Down on Science, saying, I’m parched!

Sailors everywhere wish ocean water was drinkable. What if there was a cheap way to REMOVE the salt?

Professor Liangbing Hu from the University of Maryland might have the recipe! His team started with a slice of wood as thin as a fingernail. They dissolved parts of the plank membrane to make it more flexible and porous. Then, Hu’s team coated the remaining wood with a thin, glass-like material. This made the membrane less sticky for water molecules.

When the top of the plank is heated, only the water touching it vaporizes. Water vapor flows down through the slippery, porous wood–MINUS the salt! When the water vapor reaches the cold bottom, it condenses–et voila! Drinkable fresh water!

This method saves a TON of energy. With the membrane, you only heat the water touching the surface. That means you don’t have to boil all the water to get the salt out! Plus, wood is a renewable resource. It literally grows on trees!

Desalination at night, sailor’s delight! Hmmm….slogan needs work.