Peroxide extraction

Organic material was extracted from a sample with methanol, and after evaporation the small residue was refluxed with aqueous peroxide. Extraction with ethyl acetate, separation and evaporation gave a residue which was scarcely visible but which exploded violently when the flask was moved. Several peroxidic species, including methyl hydroperoxide, peroxyacetic acid or its ethyl ester, may have been involved. See Ethyl acetate... 

The contactor finds extensive use where high performance phase separation and countercurrent extraction or washing in the one unit are required. Particularly important applications are the removal of acid sludges from hydrocarbons, shown in Figure 13.40, hydrogen peroxide extraction, sulphonate soap and antibiotics extraction, the extraction of rare earths such as uranium and vanadium from leach liquors, and the washing of refined edible oils. 

Hydrogen peroxide is extracted with water from the reaction liquor the final product so obtained contains some 20 per cent of hydrogen peroxide. Extraction is carried out in a tower in which the water flows in a downward direction over trays while the solution of quinone passes countercurrently upwards. The small amount of water remaining in the quinone phase is removed in another tower by extraction with a concentrated solution of potassium carbonate (33 to 50 per cent) finally all traces of hydrogen peroxide are eliminated by allowing the liquor to pass over a porous material on the surface of which metallic nickel and silver were deposited following this the liquor is filtered and regenerated. 

Figure 3-7 Comparison of Zinc-"Pools" in A Sample of Heat Processing Residues Before and After Treatment with pH 5/400 mV Solutions (AC = Ammonium Acetate OX = Oxalate Buffer Solution HP = Peroxide-Extraction NA = Residual Fraction)...

Capillary i.d. (mm) 0.21 Stationary phase 48 nm PDMS (1% vinyl groups), 0.3% (w/w) crossUnked with dicumyl peroxide Extraction temperature 20-23°C Extraction time —... 

There are various alternative chemical pulping methods, some of them are alkali extraction [43], alkaline and sodium chlorite treatment [30], alkaline and peroxide extraction [44], organic solvent extraction [45], acidic method [46], liquid-phase oxidation or a combination of these treatments [42,47]. 

A mixture of benzoyl peroxide (0.5 g) with poly(vinyl ethyl ether) (PVEE 100 g) is heated to 175°C. Assuming that all the peroxide decomposes and that each molecule of peroxide extracts two hydrogen atoms to produce a single cross-link, calculate the following ... 

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