Hydrogen peroxide, nitric acid, catalytic

In neutral solution hydrogen peroxide is decomposed catalytically by lead elioxielc, but in aciel solution the action is different and quantitative-.5 Thus, in the presence of nitric acid,... 

Our approach utilized the metals gold, platinum, then later gold, platinum, and nickel electroplated in succession because the catalytic decomposition of hydrogen peroxide reaction we tested was most efficiently catalyzed with platinum.After fabrication of the nanowires they were freed by removing the conductive silver backing with nitric acid and the sacrificial template with a strong base, sodium hydroxide. Then nanorods were washed with deionized water and ultracentrifuged to achieve a neutral pH. 

Initial halogenation of the oxime can use chlorine, hypobromite, bromine, or A-bromoacetamide. " Oxidation of the a-halonitrosoalkane can be achieved with nitric acid, nitric acid-hydrogen peroxide, " atmospheric oxygen, ozone, or a peroxyacid. Reduction of thea-halonitroalkaneis achieved with sodium borohydride or by catalytic hydrogenation, although potassium hydroxide in ethanol has been used for the conversion. 

Several kinetic spectrophotometric methods have been developed for selenium determination. The catalytic effect of Se(IV) on the reduction of thionine by sulfide ions has been explored. The reaction is monitored spectrophotometrically by following the decrease in absorbance at 598 nm, and the method has an LOD of 5ngml . Another method is based on the catalytic effect of selenium on the oxidation of methyl yellow by hydrogen peroxide in a nitric acid medium. It is monitored by the loss of the red color of methyl yellow. The method is extremely sensitive, with the possibility of measuring concentrations of 0.2ngml . Selenium can be also determined based on its effect on the oxidation reaction of methyl orange with bromate in acidic media. 

Santiago et al. (2(X)5) studied the oxidation of phenols in aqueous solution, by oxygen at 140 °C and 0.2 MPa pressure, over the surface of two AC, one (Cl) was prepared as a charcoal (Merck 2514), the other (CII) was prepared from coconut shell. Both carbons were initially oxidized with nitric acid, hydrogen peroxide and (NH4)2S20g. Two other carbons were prepared by acid extraction (HCl) of the parent material. It was unexpectedly observed that the various oxidation treatments only marginally affected the rates of phenol depletion, with small decreases being attributed to loss of basic surface groups. But, there were major differences in the behavior of the two carbons. Carbon Cl was much more effective than CII. The formation of stable phenolic polymers appears to block access to the catalytic sites of the carbon. 

Method (a) uses nitric acid for the oxidation of the mixture of cyclohexanol/cyclohexanon available by the hydrogenation of phenol process (b) is based on hydroxycarbonylation of 1,3-butadien and process (c) on a catalytic green chemistry reaction with water as the only side product. In this process, cyclohexene is oxidized hy hydrogen peroxide in the presence of tungsten-hased catalyst under phase-transfer catalysis (PTC). 

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