ARBON DIOXIDE

The following is a graphical display of an actual analysis comparing a deionized water system with a supercritical c arbon dioxide stem for a cleaning application. 

A simpler non-phosgene process for the manufacture of isocyanates involves the reaction of amines with carbon dioxide (CO2) in the presence of an aprotic organic solvent and a nitrogenous base. The corresponding ammonium carbamate is treated with an electrophilic dehydrating agent [198, 282, 283]. This concept has been applied to the synthesis of several aromatic and ahphatic isocyanates. The process relies on the facile formation of amineusing acid halides such as phosphoryl chloride and thionyl chloride [284, 285]. 

Berger, T.A. Deye, JL. Separation of benzene poly-carboxylic acids by packed column supercritical fluid chromatography using methane arbon dioxide mixtures with very polar additives. J. Chromatogr. Sci. 1991, 29, 141 146. 

Amlnocorbonylomlnostfccinyl Dioxide or Amlnocorbonyllmlnotoccinyl Dioxide (Am-idoc arbon-iminobem stein s aure- di azi d in Ger),... 

At a one-to-one pressure ratio of ethylene to<arbon monoxide of around 1000 psig, the major product is succinate this is in contrast to the production of acrylic acid, where succinic add was not isolated. If the olefin is left out of the reaction mix, then oxalates are produced and this is a practical route to oxalates, particularly at carbon monoxide pressures above 500 psig. The formation of water is a severe problem for the stability and activity of the catalytic system, since in the presence of water there is a parallel reaction which produces considerable amounts of carbon dioxide. 

Sodium periodate, used ong with catalytic amounts of osmium tetroxide, ruthenium dioxide or potassium permanganate, can also be employed to cleave carbon-double bonds. When used with osmium tetroxide, carbonyls are produced however, the presence of permanganate results in the formation of more highly oxidized products (carboxylic acids) from secondary carbons. 

Nakajima, T., Oda, H., Kusumoto, S., and Nogami, H. (1980). Biological effects of nitrogen dioxide and nitric oxide. In Nitrogen Oxides and Their Effects on Health (S. D. Lee, ed.), pp. 121-141. Ann Arbor Science, Ann Arbon, Michigan. 

From rhe periodic table we see that a carbon atom has a mass of about 12 ainu. The carixtn dioxide molecule, COj, consists of one c-arbon atom bonded to two oxygen atoms for a total ma.ss of about 44 amu. 

Y. Tsuji, T. Fujihara, Carbon dioxide as a carbon source in organic transformation carbon-bond forming reactions by transition-metal catalysts, Chem. Commun. 48 (2012) 9956-9964. 

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