Remediation, environmental

Halogenated hydrocarbon compounds are prevalent pollutants in the environment, and consequently several methods have been examined to identify reliable and effective ways of removing such toxic materials from the environment. Hence, Pd nanoparticles, with their excellent reducing capabihties, may represent possible candidates for this role. 

Calo and coworkers reported that Pd nanoparticles catalyzed the hydrodehaloge-nation reactions of aryl cMorides in ionic Uquids [107]. Here, molten tetrabutylam-monium bromide was used as the solvent, and tetrabutylammonium acetate as the base. The results showed the Pd nanoparticles to be capable of the hydrode-halogenation of various aryl chlorides under hydrogen, at atmospheric pressure. These authors also noted that the catalyst showed only a small decrease in catalytic activity with recycling experiments, due mainly to a minor leaching of palladium from the ionic Uquid phase. 

In further studies, Roberts et al. [108] showed that 2.4nm polysugar-stabilized-Pd nanoparticles catalyzed the hydrodechlorination of trichloroethylene, an extremely difficult pollutant to remove from the environment. Mertens and coworkers recently reported a new approach for degradation of the toxic pesticide Undane (y-hexachlorocydohexane y-HCH) through a dechlorination process catalyzed by Pd nanoparticles [109]. A heterogeneous catalyst was used in which colloidal Pd nanoparticles were immobilized onto the biomass of ShewaneUa onddensis. The results showed that, upon interaction with the Pd nanoparticles, the dechlorination of lindane in water in a membrane reactor was highly effective. Indeed, when compared to a commercially available, powdered Pd(0) material, the immobilized Pd nanoparticles showed a high catalytic activity in the dechlorination of y-HCH. 

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This chapter addresses the potential for hazardous air emissions from environmental remediation sites. These emissions can occur at hazardous spill locations, at undisturbed remediation sites, and during cleanup of remediation sites under the Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA) or the Superfund Amendments and Reauthorization Act (SARA). Air emissions may pose a potential health risk at these sites. 

Apply all elements of HAZWOPER to environmental remediation involving radioaetive wastes and materials. (Note OSHA treats radiologieal and nonradiologieal environmental remediation aetivities similarly.)... 

Case 4 Environmental Remediation Planned at an NPL-Listed Site... 

Let s discuss an example For time and material, or not to exceed jobs, some clients prefer to hire a general or main contractor for environmental remediation projects, and allow the contractors freedom in the performance of the work. In this case, the main environmental remediation contractor might hire subcontractors such as earth movers, haulers, reclaimers, drillers, or construction companies to perform different phases of a job. The main contractor organizes the work. Most of the work is performed by subcontractors. Once the job is completed, the client will get one invoice. 

Sciubba (2003) proposed an approach called the extended exergy accounting (EEA), which calculates the real, resource-based value of a commodity product. The time span of EEA is the whole life of a plant. The EEA includes the exergetics flow sheets for non-energetic costs of labor and environmental remediation expenditures, and hence uses extended exergetic content. It also defines the criterion for an optimum process or operation (Sciubba, 2003). 

Lehr, J.H., Hyman, M., Gass, T., and Seevers, W.J., Handbook of Complex Environmental Remediation Problems. McGraw-Hill Professional, New York, 2001, p. 800. 

Remediation optimization uses defined approaches to improve the effectiveness and efficiency with which an environmental remedy reaches its stated goals. Optimization approaches might include third-party site-wide optimization evaluations conducted by expert teams, the use of mathematical tools to determine optimal operating parameters or monitoring networks, or the consideration of emerging technologies. Since 1999, U.S. EPA has promoted remediation optimization in the following manner ... 

Environmental Cost Handling Options and Solutions (ECHOS), RS Means Environmental Remediation Cost Data—Unit Price, 8th Annual Edition, 2002. 

One of the major breakthroughs in nanotechnology is the use of nanomaterials as catalysts for environmental applications [149]. Nanomaterials have been developed to improve the properties of catalysts, enhance reactivity towards pollutants, and improve their mobility in various environmental media [150]. Nanomaterials offer applications to pollution prevention through improved catalytic processes that reduce the use of toxic chemicals and eliminate wastes. Nanomaterials also offer applications in environmental remediation and, in the near future, opportunities to create better sensors for process controls. 

Brady, P. V., M. V. Brady and D. J. Borns, 1998, Natural Attenuation, CERCLA, RBCA s, and the Future of Environmental Remediation. CRC Press, Boca Raton. 

METLCAP A process for encapsulating hazardous heavy metal wastes in a proprietary type of cement. Developed and offered by Environmental Remediation Technology, Cleveland, OH. 

The current oil bonanza has focused more attention on the plight of the Caspian environment, highlighting the need to take action. However, environmental remediation of existing hotspots has not been a priority for the region s governments, and their desire to develop the Caspian s oil and gas resources as a driver for economic development means that environmental protection measures are likely to take a back seat in the near-term. 

L. Mercier and T. J. Pinnavaia, Access in mesoporous materials Advantages of a uniform pore structure in the design of a heavy metal ion adsorbent for environmental remediation, Adv. Mater., 1997, 9, 500. 

Environmental laws/legislation/ regulations Environmental policy Environmental remediation, using microwaves, 16 555 Environmental resistance coatings, 13 507-508 of polyimides, 20 211 of high temperature alloys, 13 504-508 Environmental risk assessment, 12 813-814... 

Ania CO, Bandosz TJ. Surface Chemistry of Activated Carbons and its Characterization In Activated Carbon Surfaces in Environmental Remediation, Bandosz, T J, Ed. Elsevier, Oxford, 2006.159-230. 

Mine clearance, security services environmental remediation, and postconflict clearance operations. 

Dakins ME, Toll JE, Small MJ, Brand K. 1996. Risk-based environmental remediation Bayesian Monte Carlo analysis and the expected value of sample information. Risk Anal 16 67-69. 

T0276 Environmental Recycling, L.L.C., Asphalt Stabilized Base/Engineered Backfill T0277 Environmental Remediation Consultants, Inc., Biointegration... 

T0278 Environmental Remediation International (EnRem), Ltd., Soil Remediation System (SRS)... 

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