Environmental implications

The rate at which the catalyst is lost or degrades has a major influence on the design. If degradation is rapid, the catalyst needs to be regenerated or replaced on a continuous basis. In addition to the cost implications, there are also environmental implications, since the lost or degraded catalyst represents waste. While it is often possible to recover useful materials from degraded catalyst and to recycle those materials in the manufacture of new catalyst, this still inevitably creates waste, since the recovery of material can never be complete. 

We could argue that protecting the environment must take priority over financial savings. After all, investments into clean technologies, such as a gas-fired plant, have global environmental implications, so why shouldn t a utility owner/operator take a little less profit ... 

In many cases, this wastewater has environmental implications and incurs treatment costs. In addition, wastewater may wash out valuable unused raw materials from the process areas. It is very important to know how much wastewater is going down the drain, and what that wastewater contains. The wastewater-flows from each imit operation, as well as from the process as a whole, need to be quantified, sampled, and analyzed. 

THE ENVIRONMENTAL IMPLICATIONS OF ECONOMIC GROWTH AND INCREASING ENERGY CONSUMPTION... 

The 12 principles won t all be met in most real-world applications, but they provide a worthy goal to aim for and they can make chemists think more carefully about the environmental implications of their work. Success stories are already occurring, and more are in progress. Approximately 7 million pounds per year of ibuprofen (6 billion tablets ) is now made by a "green" process that produces approximately 99% less waste than the process it replaces. Only three steps are needed, the anhydrous HF solvent used in the first step is recovered and reused, and the second and third steps are catalytic. 

Sabater S, Armengol J, Sabater F et al (2000) Algal biomass in a disturbed Atlantic river water quality relationships and environmental implications. Sci Total environ 263 185-195... 

The environmental implications of rubber usage are very easily understood by considering NR, a versatile industrial material obtained from the Hevea trees as outlined in the tabular format below [4] ... 

Fox BG, Bomeman JG, Wackett LP, et al. 1990. Haloalkane oxidation by the soluble methane monooxygenase irom Methylosinus trichosporium OB3b Mechanistic and environmental implications. Biochemistry 29 6419-6427. 

Renshaw JC, LJC Butchins, FR Livens, I May, JR Lloyd (2005) Bioreduction of uranium environmental implications of a pentavalent intermediate. Environ Sci Technol 39 5657-5660. 

Moody CA, JA Field (2000) Perfinorinated snrfactants and environmental implications of their nse in firefighting foams. Environ Sci Technol 34 3864-3870. 

Hanshaw, B.B., Natural-membrane phenomena and subsurface waste emplacement, in Symposium on Underground Waste Management and Environmental Implications, Houston, Texas, Cook, T.D., Ed., Am. Assn. Petr. Geol. Mem., 1972, pp. 308-315. 

Despite much effort, antibiotic resistance continues to increase [61]. Looking back, it is clear that this was an inevitable consequence of antibiotic use [62], Antibiotic resistance, which has been recognized to be an important clinical problem, varies in prevalence from one country to another and among the pathogens themselves. This has great clinical, economic, political and environmental implications worldwide [63]. Strict adherence to the ongoing measures of infection control, education and antibiotic policy should minimize antibiotic resistance [64],... 

Mallon, B.J., Harris, F. (1984) Octanol-water partition coefficient of benzo[a]pyrene, measurement, calculation and environmental implication. Bull. Environ. Contam. Toxicol. 32, 316-323. 

Low concentrations of VOCs in ambient ah of 1 to 1,000 ppmv (parts per million based on volume) are often harmful to human health. VOCs also promote the photochemical formation of ozone and other contaminants, and in high concentrations are a fire hazard. These severe environmental implications have resulted in increasingly stringent legislation in the U.S.A. and elsewhere to limit release of VOCs into the atmosphere. Control technologies for VOCs release include combustion and vapor recovery. Vapor recovery is preferred as combustion may result in the production of other air pollutants, and destroy valuable VOCs. 

Metal ions play an important role as catalysts in many autoxidation reactions and have been considered instrumental in regulating natural as well as industrial processes. In these reactive systems, in particular when the reactions occur under environmental or in vivo biochemical conditions, the metal ions are involved in complicated interactions with the substrate(s) and dioxygen, and the properties of the actual matrix as well as the transport processes also have a pronounced impact on the overall reactions. In most cases, handling and analyzing such a complexity is beyond the capacity of currently available experimental, computational and theoretical methods, and researchers in this field are obliged to use simplified sub-systems to mimic the complex phenomena. When the simplified conditions are properly chosen, these studies provide surprisingly accurate predictions for the real systems. In this paper we review the results obtained in kinetic and mechanistic studies on the model systems, but we do not discuss their broad biological or environmental implications. 

E. Hietanen, M. Laitinen, and O. Hanninen, eds., Cytochrome P-450 Biochemistry, Biophysics, and Environmental Implications. Elsevier North-Holland, New York, 1982. 

Sewage sludge contains trace amounts of PCDD/Fs and PCBs and it is therefore important that the environmental implications of this disposal method are fully understood. Concerns center on the possible transfer of these compounds from sludge into the human food chains, mainly via grazing livestock 6. Attempts have been made to identify and quantify sources of PCDD/Fs in sewage sludge 7. 

Woynillowicz, D., Severson-Baker, C. and Raynolds, M. (2005). Oil Sands Fever -The Environmental Implications of Canada s Oil Sands Rush. The Pembina Institute www.pembina.org/pubs. 

Consider the environmental implications when choosing materials for hard landscaping, soil improving, and so forth. 

By using renewable carbon from biomass, an improvement in the CO2 balance can be achieved. However, significant effects beyond the impacts on greenhouse gas emissions are possible, e.g., soil modification, eutrophication, impact on biodiversity, land requirements and water consumption. These aspects depend on different factors like feedstock type, scale of production, cultivation and land-management practices, location and downstream processing routes. The environmental implications of agriculture are sometimes difficult to assess by the LCA methodology and require further research. 

Stable oxo-Cr(V) complexes were found to be formed with D-galactose (12) and D-fructose ligands, with EPR signals detectable even after 1 month.31>50>70 it was therefore concluded that periods of weeks are necessary to convert the Cr(VI) to Cr(III) complexes having saccharides as ligands, and this poses many environmental implications. In the studies of Cr(VI) oxidation of sugars conducted by Sala et al., the existence of intermediate Cr(V) complexes has indeed been firmly established.71... 

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