Decomposition of organic compounds

In electrocatalysis, the activated carbons, glassy carbon, and carbon black are the transitional forms used. Carbon black is the product of incomplete combustion or decomposition of organic compounds. The shape of its particles is close to spherical. They contain several carbon atom lattice fragments arranged without order. Various types of carbon black serve as substrates for metal catalysts, the properties of the carbon blacks themselves having a strong elfect on the catalytic activity of the combined catalysts thus obtained. 

However, the decomposition of organic compounds does not always lead to nontoxic solutions. Mineralization of melamine (2,4,6-triamino-l,3,5-triazine) and other chemicals was accomplished on Ti02 Degussa P-25. The formation of cyanuric acid prevents the complete mineralization of melamine as observed for atrazine and other. v-tria/incs on Ti02 photocatalysts, and the toxicity of the photocatalyzed solutions was higher than initially found for melamine [199],... 

Fermentation is the anaerobic decomposition of organic compounds, basically carbohydrate, into alcohols by the action of bacterial enzymes. Ethanol is the desired product of carbohydrate fermentation, but other alcohols, acids, ketones, and aldehydes can form as by-products. One common example of ethanol production from biomass is the fermentation of com. For illustration, this process will be summarized. 

Sanjay Amin, a student of Michael Modell at Massachusetts Institute of Technology, first discovered in the mid-1970s the effect of supercritical water for decomposition of organic compounds without forming tar [19]. 

Jin, S. and Shiraishi, F. (2004). Photocatalytic activities enhanced for decompositions of organic compounds over metal-photodepositing titanium dioxide. Chem. Eng. J. 97(2-3), 203-211. 

Hustert K, Mansour H, Korte F. 1981. A method to determine the photochemical decomposition of organic compounds in aquatic systems. 

Contamination of urban soils by POPs such as PCBs is of concern for human and ecological health. Soil contamination by metals and persistent organics disrupts nutrient cycling and is associated with declines in density of sod microfauna and lower rates of decomposition of organic compounds (Carreiro et al., 1999 Pouyat et al., 1994), an important process for the removal of organic contaminants from the environment. Ironically, urban warming may counteract this effect in some locations (McDonnell et al., 1997). 

Nanostructured Ti02 particles (particle size 5-50 nm) are used as sunscreens in the cosmetic industry. Nanosized Ti02 is an effective absorber of UV-B (280-320 nm) and UV-A radiation (320-400 nm). Because ofits small particle size, itappears transparent [2.70]. Intensive research work is in progress worldwide aimed at utilizing the photoactivity of Ti02. Titanium dioxide catalyzes the decomposition of organic compounds in wastewater [2.71]. 

Carbon nanotubes can be prepared using solvothermal reactions, - however, inherent decomposition of organic compounds into carbon and hydrogen is not yet utilized in the solvothermal synthesis of nanotubes, but hexachlorobenzene was reduced by alkali metal according to the following reaction ... 

The potential of electrosorption of various ions and anodic decomposition of organic compounds is evident from the results of the case studies in Sections 40.4 and 40.5, respectively. 

An important early method (1929) for the detection of gaseous free radicals was the metallic mirror technique of Paneth. Since then, many compounds have been used to determine the presence and extent of free radical reactions in the gas phase decomposition of organic compounds. The subject of inhibition in gas-phase reactions has been reviewed by Ashmore and by Gowenlock . 

Volume 5 The Homogeneous Decomposition of Organic Compounds Section 3. inorganic reactions... 

Carius (wet combustion) method. Decomposition of organic compounds containing halogen or sulfur in a sealed tube in the presence of red, fuming nitric acid at 250-300C in such a manner that halogen is converted to ionic halide and sulfur to sulfate. 

Many substances catalyze the decomposition of organic compounds by sulfuric acid. Mercury, copper, and selenium, either combined or in the elemental state, are effective. Mercury(II), if present, must be precipitated with hydrogen sulfide prior to distillation to prevent retention of ammonia as a mercury(II) ammine complex. 

The decreasing redox potential favors the reduction of iron-3-phosphate to iron-2-phosphate, which is dissolved from the sediments causing a strong increase of phosphate in the anoxic deepwater. Nitrate and nitrite are unstable under these conditions. Ammonium resulting from the microbial decomposition of organic compounds is the only stable nitrogen compound in the presence of hydrogen sulfide. Microbial processes also seem to be responsible for the accumulation of silicate in anoxic deep waters. 

The thermal decomposition of organic compounds can also be employed to generate small carbon clusters or atoms. The borderline with chemical vapor deposition (CVD) as presented in the next section is not really fix. In both cases, the method is based on the thermal decomposition of organic precursors. Processes both with and without catalyst have been reported. Contrary to the chemical vapor deposition, however, the catalyst (if applied) is not coated onto a substrate, but the substance or a precursor is added directly to the starting material ( floating catalyst ). The resulting mixture is then introduced into the reactor either in solid or in liquid state by a gas stream. From this point of view the HiPCo-process could also be considered a pyrolytic preparation of SWNT, but due to its importance it is usually regarded as autonomous method. 

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