COMMENT pubs.acs.org/est
Mopping Up emediative technologies are a mainstay in Environmental Science & Technology. Methods can be as “simple” as roping off the affected area and removing it for cleaning/disposal. However, as contaminants can furtively migrate through myriad environmental matrices, many researchers and innovators are pursuing more thorough solutions that impart confidence of a completed cleanup. One of the most active regions of remediation research is exploiting the cardinal rule of (wet) chemistry: like dissolves like. That is, introducing a molecule of physicochemical properties similar to those of the contaminant in an affected site should produce a good chance of the added species acting as a reactive mop or even a proactive sponge. As an example of the former case, van Leerdam et al. show how biogenic sulfur particles can be used to scrub sulfur out of hydrocarbon waste streams (Environ. Sci. Technol. DOI 10.1021/es102987p). Another illustration of like dissolving like is Kempka et al.’s reported use of residues created during coal gasification that sorb the very CO2 that might be liberated from this petrochemical fuel’s subsequent combustion (Environ. Sci. Technol. DOI 10.1021/es102839x). The fluid nature of volatiles means that they can spread afar and settle into media like soils and sediments that forbid elegant stream-fed chemical scrubbing. The lessons gleaned from using scrubbers however have permitted development of in situ methods of remediation to attenuate if not avoid sometimes laborious and expensive digging, dredging, and surfaceconducted treatment. Via chemistry, environmental engineers can thus make a janitor out of molecules to effectively clean up spills. For example, Ashworth et al. present research suggesting that organic matter introduced to soils containing fumigants like methyl iodide (CH3I) can keep such a potential toxicant at bay (Environ. Sci. Technol. DOI 10.1021/es1032822). Extending the use of OM to its superlative, Ghosh et al.’s cover Feature discusses pilot projects involving activated carbon as an in situ sorbent (Environ. Sci. Technol. DOI 10.1021/ es102694h). Their hope is that this relatively inexpensive chemical sponge can more passively treat remediation sites without disrupting the natural biogeochemical processes vital to recovery. While organic matter and activated carbon act like supersponges, other researchers are looking to reactive species that could chronically render contaminants less harmful. Shi et al. discuss one such substance of increasing popularity: zerovalent iron nanoparticles, in this case applied to groundwater treatment efforts (Environ. Sci. Technol. DOI 10.1021/es103185t). When a spill occurs, a well-stocked tool box is highly necessary for both first and ongoing responders. Unfortunately 2010 reminded how vital this is, between the Deepwater oil spill and the “red mud” in Ajka, Hungary reported on herein by Ruyter et al. (Environ. Sci. Technol. DOI 10.1021/es104000m). ES&T thus continues to welcome your reports on innovation and optimization of remediation technologies.
R
r 2011 American Chemical Society
Correction Note: The Viewpoint by Wu and Janssen (DOI 10.1021/es104032a) published in the print version of the January 15, 2011 issue should have affiliated the authors with the “Natural Resources Defense Council”, not the “National Resources Defense Council”. The online version is correct, and ES&T regrets the error. Darcy J. Gentleman Managing Editor
’ AUTHOR INFORMATION Corresponding Author
[email protected].
Published: February 11, 2011 1161
dx.doi.org/10.1021/es2001425 | Environ. Sci. Technol. 2011, 45, 1161–1161
