Silent electric discharge

Ozone is normally produced by the use of a silent electrical discharge and a number of ozonisers have been produced. Brodie s apparatus is shown in outline in Figure 10.2. 

Commercial production and utilization of ozone by silent electric discharge consists of five basic unit operations gas preparation, electrical power supply, ozone generation, contacting (ie, ozone dissolution in water), and destmction of ozone in contactor off-gases (Fig. 1). 

Carbon monosulfide [2944-05-0] CS, is an unstable gas produced by the decomposition of carbon disulfide at low pressure ia a silent electrical discharge or photolyticaHy (1 3) ia the presence or absence of sulfur (3). It decomposes with a half-life of seconds or minutes to a black soHd of uncertain composition (1—3). The monosulfide can be stabilized ia a CS2 matrix at — 196°C, and many stable coordination complexes of CS with metals have been prepared by iadirect means (8). 

C/o50-carboranes are the most numerous and the most stable of the carboranes. They are colourless volatile liquids or solids (depending on mol wt.) and can be prepared from an alkyne and a borane by pyrolysis, or by reaction in a silent electric discharge. This route, which generally gives mixtures, is particularly useful for small c/o50-carboranes (n = 5-7) and for some intermediate c/ow-carboranes (n = 8-11), e.g. 

Pyrolysis of nido- or nrac/ino-carboranes or their reaction in a silent electric discharge also leads to c/o50-species either by loss of Ht or disproportionation ... 

Dioxygen difluoride, O2F2, is best prepared by passing a silent electric discharge through a low-pressure mixture of F2 and O2 the products obtained depend markedly on conditions, and the... 

The reaction of gaseous SO2 or SO3 with O2 in a silent electric discharge gives colourless polymeric condensates of composition S03+ t (0 < jc < 1). These materials are derived from yS-SO3 by random substitution of oxo-bridges by peroxo-bridges ... 

Schoch A process for making acetylene by subjecting aliphatic hydrocarbons to a silent electric discharge. Developed by E. P. Schoch at the University of Texas. 

With Nitrogen.—Donkin has shown that when a mixture of hydrogen and nitrogen is subjected to the silent electric discharge, a partial union of the two gases takes place, with the formation of ammonia —... 

However, this reaction could in no way be regarded as commercial, as the quantity of ammonia produced after the gases have long been subjected to the silent electric discharge is only just sufficient to be identified by the most delicate means. 

Ozonolysis. Ozone was generated from oxygen by silent electric discharge, and bubbled through the reaction mixtures from a capillary tip. The ozone concentration was monitored spectrophotometrically at 350 nm by the KI method as previously described (8). 

Excimer lamps are quasi-monochromatic light sources available in UV wavelengths. The light is produced by silent electrical discharge through gas in the gap between two concentric quartz tubes. Electronically activated molecules are produced in the gas phase and decompose within nanoseconds to produce photons of high selectivity. This process is similar to the process in excimer lasers. 

Preparation of Ozone in a Silent Electric Discharge. Assemble an apparatus as shown in Fig. 41. 

Garboranes. The term carborane is widely used in American literature as a contraction of the IUPAC approved nomenclature carbaborane. The first carboranes, isomers of C2B3H5, C2B4H6, and C2B5H7, were prepared in the mid-1950s at Olin Mathiesen. These carboranes were obtained as a mixture in low yield from the reaction of pentaborane(9) with acetylene in a silent electric discharge. The discovery of the icosahedral... 

The silent electric discharge in the presence of hydrogen causes transformation of thionyl chloride into sulphur monoclxloridc and sulphur dioxide, with hydrogen chloride 10... 

In 1S78, Berthelot, by submitting a mixture of sulphur dioxide or trioxide with excess of oxygen under compression to a silent electric discharge of high potential, obtained a product which he regarded as sulphur heptoxide 1... 

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