Back in Black: Using Hydrothermal Carbonization to Clean Emissions
Good news for people who like "clean coal": a team of scientists from the Department of Colloid Chemistry at the Max Planck Institute of Colloids and Interfaces has discovered a novel "low-tech" way of using biomass to clean up carbon dioxide emissions.They suggest using a cost-efficient process known as hydrothermal carbonization (HTC) to turn fast-growing energy crops into a form of "bio-coal" that would be stored into "carbon landfills" that could act as effective carbon sinks.
Unlike other carbonization techniques, HTC is a "wet" process that eschews complex drying procedures and costly isolation schemes. Carbon structures produced through this process tend to retain most of the reactant's original carbon and are therefore the most carbon dioxide-efficient. Perhaps most significantly, the only by-product of the reaction is water.
The process is itself fairly simple: biomass is placed into an autoclave (anything from leaves, organic waste to pine cones) with water and a citric acid catalyst, and the entire mixture is heated for approximately 12 hours at 180°C.Markus Antonietti, one of the lead scientists in the study, was initially surprised by the amount of energy released by the reaction (up to a third of the combustion energy stored in the carbohydrate throughout dehydration), saying, "We underestimated this when we started. We could calculate how much energy was stored in the sugar - in the leaf material. But the first time - as you see - we had a runaway reaction, which is obviously dangerous, so we need to carry it out under safe conditions." This energy could potentially be harvested to power other reactions or processes.
Besides for its immediate use as a soil enhancing agent (by making the soil more carbonaceous and conducive to plant growth), Markus Antonietti sees in "bio-coal" the potential for a future fuel cell technology. "We are dreaming of a carbon fuel cell. That would be direct electrochemical conversion of the coal, without the actual burning process. Other applications are in chemistry, for example, directly making gasoline out of the coal."
::Back in the black: hydrothermal carbonization of plant material as an efficient chemical process to treat the carbon dioxide problem, ::Back to black: hydrothermal carbonisation of biomass to clean up carbon dioxide emissions from the past, ::A Stroke of Genius? A New Recipe for Goal
See also: ::A New Twist on Using Wood for Fuel, ::Amazon Carbon Trick Comes to Light, ::Using Woody Biomass To Extract Hydrogen From Water & Carbon From The Atmosphere, ::Montana Governor Promes Coal to Gasoline Conversion, ::Who Are The Coal-To-Liquid Players?, ::Report Re-characterizes "Clean Coal" Program: Black As Ever, ::What Did We Do to Deserve Coal for Decades?