Read the full post at Smart Planet.
Lignin is a naturally-occurring polymer commonly found in wood. Housed in the cell walls, it keeps plants upright, but it makes wood hard to break down for a number of industrial processes — including biofuel production, pulping, and papermaking. Making lignin that’s easier to degrade means those huge, worldwide processes would generate less waste and require less energy, lower temperatures, and fewer chemicals.
Now, researchers say they’ve designed plant cell walls that fall apart, self-destructing under mild processing conditions. The work could slash the cost and energy needed to turn biomass into fuel.
To get rid of lignin, engineers typically heat biomass to 170 degrees Celsius (that’s over 500 degrees Fahrenheit) for several hours in the presence of alkaline compounds, Science reports
. Its structure contains ether bonds that are difficult to degrade chemically; researchers have hoped to introduce weaker ester bonds into the lignin backbone. Previous work has suggested that the key may lie in the natural process of lignin assembly: from a pool of single molecules called monomers into a more complex polymer chain. The process could be engineered to incorporate new monomers that aren’t native to lignin — something new that could increase its degradability.