Carbamides oxidation

Based upon the concepts of the adsorption of the anode reaction product, the share of the anodic curve, on which the carbamide oxidation processes is reflected as a wave, can be explained. It may be assumed that the adsorption of the reaction product inhibits the direct oxidation of carbamide. To verify this conclusion, the anode was polarized to the electrolysis product formation potential, and the reverse sweep was stopped before the electrolysis product was reduced at the electrode. Then the carbamide oxidation process was completely inhibited on the subsequent forward sweep, and the curve exhibited only a current increase at the chlorine ion oxidation potential. 

Another indirect electrochemical heahng method involves the artificial kidney machine, with electrochemical regeneration of the dialysis solution. The common kidney machine is a dialyzer in which blood of the patient (who suffers from kiduey insufficiency) and a dialysis solution are pumped arouud iu two differeut loops, aud carbamide (urea), creatinine, and other metabolites are transferred by dialysis into the dialysis solution. For complete extraction of the metabolites, each hemodialysis session requires almost 200 L of this solution to be pumped through, so hemodialysis cau only be performed in a hospital setting. In machines equipped with electrochemical regeueratiou, the dialysis solutiou is ruu iu a closed loop, iucludiug au electrolyzer in which the carbamide is oxidized to nitrogen and carbon dioxide. The solution volume needed in this loop is rather small, so that portable kidney machines could become a reality. 

Our investigations showed that in mixed melts of eutectic composition carbamide-NH4(K)Cl, the oxidation and reduction of melt constituents take place mainly independently of each other. The anodic process at platinum electrodes in the range of potentials below 0.9V is associated with the direct oxidation of carbamide to secondary and tertiary amide compounds, accumulation of ammonium ions in the melt, and evolution of the same gaseous products as in carbamide electrolysis [8], The cathodic process is accompanied by the formation of ammonia, CO, and C02, i.e. of the same products as in pure- carbamide electrolysis. In contrast to carbamide melt, a large amount of hydrogen appears in the cathode gases of the mixed melt, and in the anode gases of the carbamide-KCl melt, the presence of chlorine has been established at potentials above 0.9V. In the... 

In an individual molten carbamide, the electrode processes are feebly marked at melt decomposition potentials because of its low electrical conductivity. Both electrode processes are accompanied by gas evolution (NH3, CO, C02, N2) and NH2CN (approximately) is formed in melt. In eutectic carbamide-chloride melts electrode processes take place mainly independently of each other. The chlorine must evolve at the anode during the electrolysis of carbamide - alkali metal and ammonium chloride melts, which were revealed in the electrolysis of the carbamide-KCl melt. But in the case of simultaneous oxidation of carbamide and NH4CI, however, a new compound containing N-Cl bond has been found in anode gases instead of chlorine. It is difficult to fully identify this compound by the experimental methods employed in the present work, but it can be definitely stated that... 

Cannizzaro reaction An internal oxidation-reduction reaction of aldehydes, carbamide Urea, carcinogenic Cancer causing. 

In 1998, Strukul and coworkers presented a diphosphine-palladium complex, with which the Baeyer-Villiger oxidation of cyclic and for the first time also acyclic ketones could be catalyzed in the presence of various peroxidic oxidants (H2O2, TBHP, KHSO5, carbamide peroxide) (Scheme 158)4 . pj-om these oxidants H2O2 turned out to be the most efficient one, whereas almost no conversion was obtained (<1% after several days) with TBHP. The authors could show that an increase in the bite angle of the diphosphine caused... 

Es ist denkbar, daB die Bildung von 5-Methoxy-benzofurazan aus 2-Acetamino-5-methoxy-l-nitro-benzol und Carbamidsaure-ethylester mit Phosphor(V)-oxid in siedendem Xylol ebenfalls uber einc Carbamid-saure-ester-Zwischenstufe verliiufi48 ... 

If the polarity of the current is not allowed to change too rapidly, it is possible, since oxidation and reduction occur successively at each pole, to accomplish electrolyses with alternating currents. Experiments with this end in view have been made b Drechsel.1 Dehydration is a case of simultaneous reduction and oxidation. The supposition that in living organisms carbamide is produced from ammonium carbamate by the splitting off of water prompted Drechsel to make experiments in this direction. When an aqueous solution of ammonium carbamate is electrolyzed with a current from a battery of 4-6 Grove cells, and platinum electrodes used, carbamide is obtained independently of the electrode material when alternating currents are employed. The reactions are supposed to be either... 

SYNS CARBAMIDE PEROXIDE GLY-OXIDE HYDROGEN PEROXIDE CARBAMIDE HYDROPERIT HYPEROL ORTIZON PERCARBAMIDE PERHYDRIT PERHYDROL-UREA THENARDOL UREA DIOXIDE UREA HYDROGEN PEROXIDE pOT) UREA HYDROGEN PEROXIDE SALT UREA HYDROPEROXIDE UREA PEROXIDE pOT)... 

Although CeO, is a good support and Ru seems to be the best active component among precious metals, there is work which shows that CeO, and/or Ru is not necessarily the best choice as catalyst components. Dobrynkin et al. carried out the wet-oxidation of N-containing compounds such as acetonitrile, carbamide. 

Sinensky MC, Leiser AL Babich H (1995) Oxidative stress aspects of the cytotoxicity of carbamide peroxide in vitro studies. Toxicology Letters 15 101-109. 

The active ingredients are diphosphonic acids - dicarboxypropane diphosphonic acid (DPD), hydroxymethylene diphosphonic acid (HDP or HMDP), hydroxyethylidene diphosphonic acid (EHDP), methylene diphosphonic acid (MDP) - or their sodium salts. As stabilizers are used N-(4-aminobenzoyl)-L-glutaminic acid, gentisic acid (2,5-dihydroxybenzoic acid), ascorbic acid, or carbamide. For reduction of Tc-pertechne-tate to lower oxidation states, tin(II) chloride and tin(II) fluoride are employed. 

CARBAMIDE, CARBAMIDE ACID or CARBAMIDE RESIN (57-13-6) Heat or contact with hot surfaces forms anhydrous ammonia and nitrous vapors. Violent reaction with strong oxidizers, chlorine, inorganic chlorides, chlorites, chromyl chloride, dichromates. 

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