Active carbon, hydrogen peroxide

Active carbon, hydrogen peroxide determination, 638 Active oxygen see Peroxide value ACV see Acidity value... 

Water from the wastewater treatment plants of paper mills, power plants, etc., contains high chlorine residues in aqueous media, which causes environmental concern. Several methods have been used for dechlorination, including granular activated carbon, hydrogen peroxide, sodium thiosulfate, ammonia, sodium sulfite, and metabisulfite. In addition, ferrous sulfate hep-tahydrate has also been proposed for the removal of chlorine residues. 

An ammoniacal solution is added just before use to activate the hydrogen peroxide. Ammonia is preferred over sodium carbonate (40) or ethanolamines for maximum bleaching. The alkaline solution can be formulated iato a shampoo vehicle with oleate soaps or ethoxylated fatty alcohols. When the bleach is appHed to areas such as new hair growth, a viscous cream or paste may be preferred, formulated with fatty alcohols, alkanolamides, or other thickeners. 

In fact, carbon and graphite exhibit good electrochemical activities for oxygen reduction, high overpotential for hydrogen evolution, and low catalytic activity for hydrogen peroxide decomposition (Do and Chen 1994a, b Ponce-de-Leon and Pletcher 1995). 

From a practical point of view, the performance of 02 cathode materials that display poor or no activity for hydrogen peroxide reduction, such as carbon in alkaline... 

Tung, H.-C., Kang, C., and Sawyer, D.T. (1992) Nature of the Reactive Intermediates from the Iron-Induced Activation of Hydrogen Peroxide Agents for the Ketonization of Methylenic Carbons, tlie Monooxygenation of Hydrocarbons, and the Dioxygenation of Arylolefins, J. Am. Chem. Soc. 114, 3445-3455. 

Huang JS, Wang DW, Hou HQ, You TY (2008) Electrospun palladium nanoparticle-loaded carbon nanofibers and their electrocatalytic activities towards hydrogen peroxide and NADH. Adv Fund Mater 18(3) 441 48. doi 10.1002/adfm.200700729... 

In this work, catalysts containing iron supported on activated carbon were prepared and investigated for their catalytic performance in the direct production of phenol fiom benzene with hydrogen peroxide and the effect of Sn addition to iron loaded on activated carbon catalyst were also studied. 

Catalysts were prepared with 0.5, 1.0, 2.0 and 5.0 wt% of iron loaded on activated carbon. Benzene hydroxylation with hydrogen peroxide as oxidant was carried out. The conversion of benzene, selectivity and yield of phenol for these catalysts are shown in Fig. 4. As the weight of loaded metal increased the benzene conversion increased by about 33% but the selectivity to phenol decreased. The yield of phenol that was obtained with S.OFe/AC was about 16%. 

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