Oxygen combustion "bomb" calorimeter

Parr adiabatic calorimeter containing a Parr double-valve oxygen combustion bomb. The water equivalent of the calorimeter was determined from the combustion of a weighed sample of benzoic acid standardized by the National Bureau of Standards (NBS). The agreement between results of any two acceptable runs was better than 0.10%. 

Measuring the gross heating value (mass) is done in the laboratory using the ASTM D 240 procedure by combustion of the fuel sample under an oxygen atmosphere, in a bomb calorimeter surrounded by water. The thermal effects are calculated from the rise in temperature of the surrounding medium and the thermal characteristics of the apparatus. 

Aniline, C6H5NH2(1), is a derivative of benzene in which a hydrogen atom has been replaced by an NH2 group, (a) Write the balanced equation for the combustion of aniline, (b) What is the mass of each product when 0.1754 g of aniline is burned in excess oxygen (c) If the bomb calorimeter in which this reaction was carried out had a volume of 355 mL, what minimum pressure of oxygen at 23°C must have been used to ensure complete combustion Assume that the volume of the aniline is negligible. 

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... 

A 4.9 g sample of the liquid siloxane in a glass dish was put into a bomb calorimeter (on an open bench) containing 5 ml of sodium hydroxide solution to absorb combustion gases. The electric igniter system consisted of a metal wire in contact with a cotton-wool wick which dipped into the siloxane sample. The bomb was sealed, pressured up to 39-44 bar with oxygen, and the igniter was fired. A violent explosion blew the lid off the bomb (rated at 190 bar working, 250 bar test), and examination of the deformed bomb indicated that a maximum detonation pressure of around 900 bar had been attained. 

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... 

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,... 

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... 

The American Society for Testing and Materials (ASTM) has developed a series or standard test methods for both solid and liquid fuels in oxygen bomb calorimeters. Advanced combustion calorimeters are capable of performing 8 to 10 tests per hour with a precision of 0.1%. 

The calorific value is the heat produced by the combustion of a unit quantity of coal in a bomb calorimeter with oxygen and under a specified set of conditions (ASTM D-121 ASTM D-2015 ASTM D-3286 ISO 1928). For the analysis of coal, the calorific value is determined in a bomb calorimeter either by a static (isothermal) method or by an adiabatic method, with a correction made if net calorific value is of interest. The unit is calories per gram, which may be converted to the alternate units (1.0 kcal/kg = 1.8 Btu/lb = 4.187 kJ/kg). 

The bomb calorimeter provides the most suitable and accurate apparatus for determination of the calorific values of solid and liquid fuels. Since the combustion takes place in a closed system, heat transfer from the calorimeter to the water is complete, and since the reaction is one between the fuel and gaseous oxygen, no corrections are necessary for the heat absorbed during the reduction of the oxidizing agent. In addition, the losses due to radiation can be reduced to comparatively small quantities, and more important, can be determined with a considerable degree of accuracy. Corrections due to the heat evolved in the formation of nitric and sulfuric acids under the conditions existing in the bomb can be determined accurately. 

Gross calorific value (gross heat of combustion at constant volume) heat produced by combustion of a unit quantity of a solid or liquid fuel when burned at constant volume in an oxygen bomb calorimeter under specified conditions, with the resulting water condensed to a liquid not applied to gaseous fuels and applies to a volatile liquid fuel only if it is suitably contained during the measurement closely related to the internal energy of combustion for the same reaction at constant standard temperature and pressure. 

For the experimental determination, we use a bomb calorimeter and assume that the process takes place at constant volume, so that the volume of the chemical system remains constant. An excess of oxygen must be used to ensure complete combustion. The initial state of the chemical system is then a mixture of CH4 and 02 with known mole numbers of CH4 and 02 at a temperature equal or close to 298 K and at a measured total pressure. The individual gases as well as the gas mixture are not ideal gases. The final state is a two-phase system at a known temperature and measured (or calculated)... 

The thermal combustion properties measured in the test are related to the flammability characteristics of the material.5155 For example, the heat release temperature from method A approximates the surface temperature at ignition (Section 14.3.2.1). The net calorific value from method B approximates the net heat of combustion measured in an oxygen bomb calorimeter. 

A light fuel oil with an average chemical composition of C<,H15 is burned with oxygen in a bomb calorimeter. The heat evolved is measured as 47,730 J g-1 for the reaction at 25°C. Calculate the standard heat of combustion of the fuel oil at 25°C with H20(s) and C02(fl) as products. Note that the reaction in the bomb occurs at constant volume, produces liquid water as a product, and goes to completion. 

The heat of combustion is the amount of heat released when a compound is burned with an excess of oxygen in a sealed container called a bomb calorimeter. If the compound has extra energy as a result of ring strain, that extra energy is released in the combustion. The heat of combustion is usually measured by the temperature rise in the water bath surrounding the bomb. ... 

The standard calorimeter system for this series of experiments was specified as the NBS calorimeter containing the Parr fluorine combustion bomb plus sample ampoule. The standard bomb was defined as the Parr fluorine combustion bomb plus sample ampoule minus the water, the benzoic acid pellet, the Hastelloy cup containing the pellet, the oxygen, and the nitrogen used to pressurize the ampoule. 

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