Oxygen bomb

Other Elements. To determine chlorine, the sample is mixed with Eschka s mixture and burned to convert the chlorine to chloride or decomposed in an oxygen bomb (18). Chloride is determined by titration (D2361) or using a chloride selective electrode (D4208) (18) (see... 

A PET oligomer isolation method has utilised chloroform extraction in a Parr bomb lined with a Teflon-TFE fluoro-carbon resin [40]. The analytics of fluoropolymer processing aids (combustion analysis, XRF, EUR, 19F NMR, OM) have recently been described [29]. Combustion analysis (Parr Oxygen Bomb Calorimeter) can be used for quantitative analysis... 

The heat of combustion of solids or liquids is usually measured in a device known as an oxygen bomb calorimeter. Such a device operates at a constant volume between states 1 and 2, and its heat loss is measured by means of the temperature rise to a surrounding water-bath. This is schematically shown in Figure 2.2. The combustion volume is charged with oxygen and a special fuel is added to ensure complete combustion of the fuel to be measured. Since the process is at constant volume (V), we have... 

Although most of the fluorine calorimetry has been done with the elements, it has been used to burn oxides, carbides, nitrides, and chal-cogenides and hence determine their heats of formation. In some instances it has proved superior to oxygen bomb calorimetry. Thus the oxidation of boron tends to be incomplete because of oxide coating, whereas fluorination produces gaseous boron trifluoride without surface inhibition. A summary of modem fluorine calorimetry results is assembled in Table III. 

Alternatively, the combustion of a certified reference material can be used. Since 1934, benzoic acid has been the internationally accepted primary standard material for determination of the energy equivalent of oxygen-bomb calorimeters [39,40]. In this case,... 

Fluorine bomb calorimetry is in many aspects similar to oxygen bomb calorimetry. The experiments are carried out in isoperibol instruments, which, except for the bomb, are basically identical to those described in sections 7.1 and 7.2. The procedure used to calculate Acf/°(298.15 K) from the experimental results is also analogous to that discussed for oxygen bomb calorimetry in section 7.1. Thus, a temperature-time curve, such as the one in figure 7.2, is first acquired, and the corresponding adiabatic temperature rise, A Tad, is derived. 

M. E. Minas da Piedade. Oxygen Bomb Combustion Calorimetry Principles and Applications to Organic and Organometallic Compounds. In Energetics of Stable Molecules and Reactive Intermediates, M. E. Minas da Piedade, Ed. NATO ASI Series C, Kluwer Dordrecht, 1999. 

HEAT FLOW CALORIMETRY OXYGEN BOMB CALORIMETRY REACTION SAFETY CALORIMETRY... 

Plewinsky, B. et al., Thermochim. Acta, 1985, 94, 33-43 Safety aspects of the combustion of various materials in an amosphere of pine oxygen under the conditions prevailing in oxygen bomb calorimetry were investigated experimentally. The combustion of a stable substance (benzoic acid, used to calibrate bomb calorimeters) in oxygen gives a relatively slow combustion, with a low rate of pressure increase of 17 bar/s to a maximum of 64 bar in 2.3 s, for... 

Total decomposition of the sample, the purpose of which is to release fluorine from inorganic or organic matrixes and convert it to fluoride ions, is usually a prerequisite for determining the amount of total fluorine. Commonly used procedures involve oxygen bomb combustion in a closed bomb [176,180], open ashing [181,182], alkali hydroxide or alkali carbonate fusion [151,183-187], pyrohydroly-sis [187-191], acid extraction [192,193] and microwave acid digestion [194-196]. 

P. Venkateswarlu, Determination of total fluorine in serum and other biological materials by oxygen bomb and reverse extraction techniques. Anal. Biochem. 68 (1975) 512-521. 

D.A. Levaggi, W. Oyung, M. Feldstein, Microdetermination of fluoride in vegetation by oxygen bomb combustion and fluoride ion electrode analysis, J. Air Pollut. Control... 

In addition to the analysis of the thermal stability of the perchloric acid organic reaction media mixtures, a procedure was worked out to determine the fate of the perchloric acid by chlorine analysis of the batch, effluent streams, etc. Preliminary analyses on selected process samples showed no tendency for perchloric acid to concentrate in recycle material and therefore build up in the reactor. A total of less than 1% of the initial charge of perchloric acid (total chlorides calculated as perchloric acid) was found in the combined recovered acid-ester and olefin fractions. Less than 1 % of the initial charge of perchloric acid was found in the finished ester. The analytical method used was an oxygen bomb decomposition, followed by titration of chlorides with 0.0liV silver nitrate, using a recording automatic titrator. The eventual fate of the perchloric acid catalyst was... 

Formation and Preparation.—(1) Sulphur trioxide is formed to a small extent together with sulphur dioxide when sulphur 1 or compounds of sulphur 2 are burned in oxygen or air (see p. 103). In an oxygen bomb, in the presence of a compound which on combustion yields water vapour and oxides of nitrogen, for example ammonium nitrate, the combustion goes completely to sulphur trioxide (see p. 45 ).3... 

The Determination of Selenium. The most difficult trace element to determine in coal by wet chemical methods is selenium. Two alternative dissolution techniques can be used—H. L. Rooks combustion method (7) and the oxygen bomb combustion method (4). Also, two alternative analytical methods can be used—the hydride evolution method (5) and the graphite furnace method. 

Any oxygen bomb calorimeter consists of four essential parts (I) a bomb or vessel in which the sample is burned (2) a bucket or container which holds the bomb as well as a precisely measured quantity of water to absorb the heat released from the bomb and a stirring device to aid in achieving rapid thermal equilibrium (3) a jacket for protecting the bucket from transient thermal stresses and (4) a thermometer for measuring temperature changes within the bucket The cross section of a simple calorimeter is shown in Fig. I. 

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