Reaction/extraction technology

T0736 SOUND/epic, Dispersion by Chemical Reaction (DCR) Technology T0745 State University of New York, Oswego, Electrochemical Peroxidation (ECP) T0747 SteamTech Environmental Services and Integrated Water Resources, Inc., Steam-Enhanced Extraction (SEE)... 

T0736 SOUND/epic, Dispersion by Chemical Reaction (DCR) Technology T0755 Supercritical Carbon Dioxide Extraction—General T0794 Thermal Desorption—General... 

The reactor is an aerobic, plug flow, packed-bed biofihn reactor. Reticulated polyurethane (PUR), a foam with large surface area, is used as the substrate for microorganisms. The substantial area available on the PUR for contact results in a high biomass concentration and thus high reaction rates at short retention times. Biopur can be used in conjunction with soil vapor extraction technology. 

Supercritical fluids (scf) are highly compressed liquids or gases. The latter already have an established role in "clean extraction (substitution of chlorinated/organic solvents) on an industrial scale (e. g. decaffeination of coffee and tea, extraction of hops, spices, etc.). The specific physical and chemical properties of scf make them particularly suitable for a variety of other applications, e. g. reactions, powder technology and impregnation. 

This is an extraction technology that produces metal by reaction of one of its compounds with a metallic reducing agent through thermal methods. 

Extraction is often used in the fine-chemicals and biotechnology industry. Extraction technology has a number of distinct advantages (selectivity, capacity, robustness and good scalability), but an even longer list of disadvantages expensive solvent recovery, many practical problems such as emulsification and the mutual miscibility of solvent and water, solvent aging by oxidation and other chemical reactions, environmental and safety aspects because of toxicity, explo-sivity and flammability. 

The two fluids most often studied in supercritical fluid technology, carbon dioxide and water, are the two least expensive of all solvents. Carbon dioxide is nontoxic, nonflammable, and has a near-ambient critical temperature of 31.1°C. CO9 is an environmentally friendly substitute for organic solvents including chlorocarbons and chloroflu-orocarbons. Supercritical water (T = 374°C) is of interest as a substitute for organic solvents to minimize waste in extraction and reaction processes. Additionally, it is used for hydrothermal oxidation of hazardous organic wastes (also called supercritical water oxidation) and hydrothermal synthesis. 

When the products are partially or totally miscible in the ionic phase, separation is much more complicated (Table 5.3-2, cases c-e). One advantageous option can be to perform the reaction in one single phase, thus avoiding diffusional limitation, and to separate the products in a further step by extraction. Such technology has already been demonstrated for aqueous biphasic systems. This is the case for the palladium-catalyzed telomerization of butadiene with water, developed by Kuraray, which uses a sulfolane/water mixture as the solvent [17]. The products are soluble in water, which is also the nucleophile. The high-boiling by-products are extracted with a solvent (such as hexane) that is immiscible in the polar phase. This method... 

Microwave and fluorous technologies have been combined in the solution phase parallel synthesis of 3-aminoimidazo[l,2-a]pyridines and -pyrazines [63]. The three-component condensation of a perfluorooctane-sulfonyl (Rfs = CgFiy) substituted benzaldehyde by microwave irradiation in a single-mode instrument at 150 °C for 10 min in CH2CI2 - MeOH in the presence of Sc(OTf)3 gave the imidazo-annulated heterocycles that could be purified by fluorous solid phase extraction (Scheme 9). Subsequent Pd-catalyzed cross-coupling reactions of the fluorous sulfonates with arylboronic acids or thiols gave biaryls or aryl sulfides, respectively, albeit it in relatively low yields. 

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