Unwilling to reduce their energy consumption, the United States is seeking technical means to limit the resulting greenhouse gas emissions without significant additional costs, for example by capturing these gases at the source. The country, which has fossil fuel reserves for about a century, prefers to consume "clean" rather than less. At the Goldwater Laboratory of Arizona State University, Andrew Chizmeshya and Michael McKelvy are studying a method to neutralize carbon dioxide (CO2) by combining it at high temperature with two available minerals (olivine and serpentine) in an aqueous solution of sodium bicarbonate and sodium chloride. The reaction produces magnesium carbonate, a stable compound that can be easily stored. At present, the minerals must be pretreated to prevent the formation of a kind of surface crust which considerably slows down the reaction. But these precautions increase the cost of the device, estimated at about 70 dollars per tonne while the target is 10 dollars. The two researchers, working with a dozen scientists from four other laboratories, have thus developed a micro-reactor (for which they have applied for a patent) in order to observe the process of mineral carbonation at the atomic level and to see how to break the incriminated crust as it is formed. This work could also pave the way for the development of a process for the reprocessing of asbestos fibers. Overall, the Department of Energy devotes some 80 million dollars annually to the financing of 65 CO2 capture and storage research projects, to which is added 18 million dollars from the Department of Agriculture - two posts in rise in the Bush Administration's latest budget.
source: www.netl.doe.gov (.pdf)