Feb. 4, page 18: A story on coping with the helium shortage erroneously referred to helium as a molecule. Under normal conditions, helium is a monoatomic gas.
“Treating Water from Hydraulic Fracturing” left an incorrect perception that the use of CO2 to carry proppant into the fracture is “new technology” and that Linde is “testing a fracking process” using foamed CO2 (C&EN, Oct. 15, 2012, page 13).
In fact, Linde has been providing CO2 and N2 as fracturing alternatives to water for decades. Fracturing liquids that are energized with CO2 or N2 can significantly reduce the volume of water required in hydraulic fracturing of unconventional sources and improve overall well performance.
Thank you for this opportunity to clear this up.
Corporate Communications, Linde North America
Murray Hill, N.J.