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Open manganese dioxide

Each still consists of an iron pot covered with a leaden lid to which are luted, say, two earthenware arms each of which is connected with a train of about five stoneware aludels or udells supported on a wooden framework as illustrated in Fig. 13. Each udell has a stoneware stopper below so as to permit condensed water (with the 3 halogens in solution) to be drained off as required. Manganese dioxide is added to the liquid. The still is heated by an open Are, and iodine and steam are evolved. The liquor from the still is a troublesome waste product. The udells are emptied when required. The bromine is in too small a quantity to pay to collect. The iodine from the udells requires further purification. [Pg.43]

Attempts to prepare 7-keto-compounds from the bases (138) and (139) by the action of manganese dioxide and titanium chloride gave the ring-opened compounds (140) and (141).167... [Pg.105]

Peroxybenzoic acid converts A -methylindoline into o-dimethylami-nobenzaldehyde (equation 522) [311], and manganese dioxide opens the ring in dibenzylpiperazine to give A, N -dibenzyl-yV,yV -diformylethylene-diamine (equation 523) [818]. [Pg.244]

There are few data on the oxidation of noncondensed A-aminoazoles. Manganese dioxide converts 1,2-diamino-4-arylimidazoles into complex mixtures of the corresponding 3-amino-1,2,4-triazines (320), 2-aminoimid-azoles (321), 1,2,3-triazoles (322), and some open-chain compounds (76TL903 78JOC2693). The yield of 1,2,4-triazines 320 is usually less than 25%, but on oxidation of l,2-diamino-4,5-diphenylimidazole, it increases to 62%. It is assumed that triazines 320 are formed via a nitrene mechanism, whereas for 1,2,3-triazoles 322, the diazene mechanism is postulated. However, the latter may also apply to compounds 320. [Pg.175]

The zinc-air treatment is somewhat simpler because the absence of manganese dioxide means that the acid treatment is not necessary. After the batteries have been opened, they are immersed in sodium hydroxide within a trummel. The fines, containing zinc powder, zinc oxide, carbon and lime are suspended in solution and undergo the same zinc treatment as described above. After washing, the large fraction consisting of polypropylene pieces, steel and carbon are sorted and recycled within specialist industries. [Pg.193]


See other pages where Open manganese dioxide is mentioned: [Pg.521]    [Pg.525]    [Pg.95]    [Pg.63]    [Pg.603]    [Pg.613]    [Pg.391]    [Pg.140]    [Pg.34]    [Pg.791]    [Pg.791]    [Pg.137]    [Pg.902]    [Pg.52]    [Pg.294]    [Pg.229]    [Pg.902]    [Pg.421]    [Pg.137]    [Pg.739]    [Pg.739]    [Pg.3816]    [Pg.52]    [Pg.179]    [Pg.447]    [Pg.521]    [Pg.525]    [Pg.350]    [Pg.360]    [Pg.533]    [Pg.45]    [Pg.618]    [Pg.271]    [Pg.170]    [Pg.414]    [Pg.62]    [Pg.313]    [Pg.113]    [Pg.78]    [Pg.27]    [Pg.78]    [Pg.739]    [Pg.20]    [Pg.150]    [Pg.63]   
See also in sourсe #XX -- [ Pg.119 ]




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