Oxygen bomb calorimetry

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. 

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. 

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... 

Oxygen Bomb Calorimetry and Combustion Methods, Tech, manual 130, Parr Instrument Co., Moline, IL. 

The enthalpy of formation is calculated from A H (298.15 K) = -591.5 kcal mol" for SiC(B)+4F2(g)+SiF (g)+CF (g), based on the tentative value of AjH (CF, g, 298.15 K) = -223+1 kcal raol". Greenberg ( ) determined the enthalpy of reaction by fluorine bomb calorimetry. Data of Humphrey ( ) obtained by oxygen bomb calorimetry yield a which is over 3 kcal more... 

We dismiss two calorimetric values due to probable bias. These include AjH (t) -112 kcal mol from oxygen-bomb calorimetry (2) and A.H (g) -117.4 1.7 kcal raol from solution calorimetry (4) in dilute aqueous NaOH. Revised auxiliary 1 —1 data (1, 5) change these values to A H (g) -115 (,3) and -124 kcal mol . Wagman et al. (5) adopted -122.6 kcal mol, ... 

Several methods of sulfur determination are used for carbon black. They include oxygen bomb calorimetry, high-temperature combustion with an iodometric detection procedure and an infrared detection procedure. The results are given as percentage of sulfur. 

The heat of combustion (AcH) of dinitrobiuret (DNB) was determined experimentally using oxygen bomb calorimetry AcH(DNB) = 5195 200kjkg The standard heat of formation (AfH°) of DNB was obtained on the basis of quantum chemical computations at the electron-correlated ab initio MP2 (second order Moller-Plesset perturbation theory) level of theory using a correlation consistent double-zeta basis set (cc-pV-DZ) AfPf°(DNB) =- 353 kj mol - 1829 kj kg (Fig. 34). The detonation velocity (D) and detonation pressure (P) of DNB was calculated using the empirical equations by Kamlet and Jacobs D(DNB) = 8.66 mm xs P(DNB) = 33.9 GPa. 

Bostic et al. (113) reported on a series of PCT fabrics treated with selected phosphorus- and halogen-containing flame retardants which were studied by static oxygen bomb calorimetry. The amount of heat evolved when these fabrics were burned in the open atmosphere was determined indirectly using calculations based on Hess law of summation. The heat evolution, when corrected for contributions due to burning of the flame retardant, appeared to correlate with the efficiency of the flame retardant treatment and was interpretable in terms of mechanisms of flame retardant action. 

---