Recovery/reuse

The economic balance must be considered between recovery, reuse, and modification of a waste material or by-product and its disposal. The future is expected to bring iacreases ia the practice of recycle, recovery, modification, and upgrading of wastes of all sorts, and a reduction ia disposal by iaciaeration (qv), biochemical oxidation, or discharge to the environment (see Recycling). 

Recovery Reuse Metals Sometimes energy prohibitive... 

P31 Reverse Osmosis (other than for recovery/reuse) ... 

P31 Reverse Osmosis (other than for recovery/reuse) per million if in milllgrams/cubic meters, multiply by 0.773 to ... 

Process material conservation is practiced by the recovery, reuse, or purification of the materials used in the processes. In the nickel deposition process the nickel solution is filtered to reduce its iron content, giving a longer life to the solution. Because the bath is dumped less often, the pollutant load is reduced. 

In this chapter, the recent advances in amidocarbonylations, cyclohydrocarbonylations, aminocarbonylations, cascade carbonylative cyclizations, carbonylative ring-expansion reactions, thiocarbonylations, and related reactions are reviewed and the scope and mechanisms of these reactions are discussed. It is clear that these carbonylation reactions play important roles in synthetic organic chemistry as well as organometallic chemistry. Some of the reactions have already been used in industrial processes and many others have high potential to become commercial processes in the future. The use of microwave irradiation and substitutes of carbon monoxide has made carbonylation processes suitable for combinatorial chemistry and laboratory syntheses without using carbon monoxide gas. The use of non-conventional reaction media such as SCCO2 and ionic liquids makes product separation and catalyst recovery/reuse easier. Thus, these processes can be operated in an environmentally friendly manner. Judging from the innovative developments in various carbonylations in the last decade, it is easy to anticipate that newer and creative advances will be made in the next decade in carbonylation reactions and processes. 

Figure 12. Relation of glucose selling price to delivered cellulose substrate costs for enzymatic hydrolysis process. Data for 250,000 t/yr plant 90% overall process efficiency, 50% enzyme recovery (reuse).

The main driving force towards recycling has been national and international plastic waste management policy. Within the EU, the policy is based on waste hierarchy, meaning that the first choice is waste prevention and then waste recovery (reuse, recycling and energy recovery), with preference to material recovery. Thus the type of legislation found is ... 

With increasing production volumes of chemicals predicted for the next 20 years [242], the economic advantages of the costly application of recovery, reuse and recycling may prove limited unless regulatory controls are put in place. Chemical bans are now being enforced to ensure that material recovery and recycling targets are technically and economically achievable [243, 244]. 

RING-CLOSING METATHESIS OF AN ACYCLIC DIENE AND SUBSEQUENT CATALYST RECOVERY/REUSE... 

Since these examples are for research-laboratory work, economic concerns such as solvent recovery, reuse, or cost are not considered. Solvents such as acetonitrile or tetrahydrofuran have some immiscibility properties that are quite useful in laboratory work. However, economic costs would likely prevent their use in a commercial process. The goal in each example is to end up with a solvent extract that can easily be vacuum-concentrated and used in final purification steps (i.e., crystallization, precipitation, chromatography). 

Waste Management, Control, Recovery Reuse Kirov 1975 Analysis of Organic Pollutants in Water Leithe 1973 Extraction of Minerals and Energy Deju 1974... 

Garrison, M.M. 1994. Conventional weapons utilization in Ukraine and Belarus Recovery-reuse and conversion. Proceedings of the 2nd Demilitarization Symposium, Arlington, Va., May 23-25. Arlington, Va. National Defense Industrial Association. 

In the year 2000, the EU also instituted a broader approach of requiring that packaging adhere to what are referred to as essential requirements related to source reduction, minimal presence of hazardous substances, and the design and production to facilitate recovery, reuse, and recycling. Adoption of standards necessary to enforce the requirements is up to individual member states. Some countries have issued detailed standards (UK, Erance, Czech Republic) but the others have only much more general language [7]. In much of the developing world, open dumps are still a common method of waste disposal, even in major urban areas. The appreciable... 

On-Site Recovery/ Reuse reuse of waste materials or energy streams in the same process or for another useful application within the company... 

Stricter regulations regarding air pollution control, water pollution control and waste management have forced companies to remove volatile organics from atmospheric emissions and workplace environments. But apart from compliance with these requirements, economic factors are decisive in solvent recovery. Reuse of solvent in production not only reduces operating cost drastically but may even allow profitable operation of a recovery system. 

Nevertheless, alternative or nontraditional methods are interesting fields for new applications, due to the need for more selective synthetic and environmentally friendly methods, including the aspect of reaction media (solvent) and energy transfer into a reaction system. The use of supercritical fluids (SCFs) or ionic liquids (IL) as process solvents is well established. From the view point of green chemistry or sustainable chemisfiy, it is SCFs, especially supercritical carbon dioxide (SCCO2), that are the main focus [2, 3]. It is currently under discussion whether ioiuc liquids as alternative process solvents are beneficial. In general, more fundamental problems, like recovery, reuse, purification and ecology (eco-toxicity), have to be solved. 

DaimlerChrysler Corporation Winking with Recyclo s to Increase Recovery, Reuse of Plastics from Automobiles, Environment News Service, Sept. 19,2000. 

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