Halogenated Organic Compounds Research Articles

Gaschromatographie : V. Die beziehung zwischen den elutionsdaten und dem molvolumen

Gas chromatography. V. The relationship between retention data and molar volume A simple relationship, which could be used for the correlation and identification of organic and organosilicon materials in the analysis of mixtures was derived from the laws for the chromatographic separation of compounds. The logarithm of the retention data for members of a homologous series of organic compounds (those materials which have the same structure but contain different numbers of the same organic groups or halogen atoms, or organic compounds with similar structural properties (halogenorganic compounds)) is linearly proportional to the molar volume ▪ where V g is specific retention volume, V M is molar volume, and k 1 , k 2 are constants. The graphic representation of this relationship is a straight line whose slope is characteristic for each individual organic and organosilicon group of compounds. This relationship was verified with organic and organosilicon compounds. The relationship was applied to the gas chromatoraphic separation of the low-molecular-weight organosilicon compounds, for the purpose of identification.

Iodometric microdetermination of chlorine and bromine in some highly halogenated organic compounds

Highly halogenated organic compounds are combusted in a oxygen flask using water as absorbant in the case of chlorine and 0.05% hydrogen peroxide in the case of bromine. The halogenide ion formed is determined by an iodometric procedure. Results showed an average error of ± 0.1% for Cl and ± 0.2% for Br. They are in close agreement with those obtained by a mercurimetric titration. The iodometric titration is to be preferred because of simplicity and rapidity

The simultaneous microdetermination of carbon, hydrogen and halogen in highly chlorinated or brominated organic compounds

The simultaneous determination of chlorine or bromine together with carbon and hydrogen in highly halogenated organic compounds was achieved by dry-oxidation of the sample with oxygen either in an empty or packed combustion tube. The carbon dioxide and water produced were absorbed in the usual way in soda-asbestos and anhydrone. The halogen was absorbed on a silver gauze roll kept at 550 °C, placed in a specially-designed silica absorption tube, connected externally between the combustion and water absorption tubes, and determined gravimetrically. The method is simple, rapid, and accurate.

On the use of sodium borohydride in the microdetermination of chlorine or bromine in highly halogenated organic compounds

A description is given of a modification of the combustion flask method ofSchoniger which makes possible the microdetermination of chlorine or bromine in highly halogenated organic compounds. Sodium borohydride as a reducing agent is employed in the absorbing solution. For simplicity and rapidity in operation, the proposed method has a decided advantage over more conventional ones. It is also quite reliable.

Further studies on the use of the oxygen flask for the micro-determination of chlorine or bromine in some highly-halogenated organic compounds

The combustion of some highly halogenated organic compounds is discussed, and it is shown that free halogen is formed. A suitable micromethod is described for the determination of chlorine or bromine in these compounds by the oxygen flask method with alkaline bisulphite or aqueous sulphur dioxide as reducing absorbents.

Microdetermination of chlorine or bromine in highly halogenated organic compounds

The microdetermination of chlorine or bromine in highly halogenated com pounds is described. The oxygen flask is used for aromatic, aliphatic and liquid sam ples with high halogen contents. A microfusion method for some of these compounds is also discussed. As many compounds as possible covering different structures were analysed. Satisfactory results were obtained.

Polarography of halogen organic compounds communication 2. determination of reaction stoichiometry by means of latent limiting currents

1. Using the equations for latent limiting currents, given by Kemula and Grabowski, expressions are found for determining the stoichiometric coefficients of a reaction which is capable of reducing a substance with the reduction products of another substance. 2. The correctness of the relations derived is shown with several organic compounds, and the proposal is made to use latent limiting hydrogen currents to identify the products of electroreduction. 3. This method has been used to demostrate the reduction mechanism of 2,3-dibromopropionitrile with formation of acrylonitrile in the first wave.