Determination of Attenuation Properties of Some Petroleum Products in Ghana by Gamma Ray Absorption Technique

Abstract

The mass attenuation coefficient 𝜇𝜌 and the mass energy absorption coefficient 𝜇𝑒𝑛𝜌 are important parameters to characterise the penetration and the interaction of gamma rays in chemical materials such as hydrocarbons. Accurate determination of values of 𝜇𝜌 and 𝜇𝑒𝑛𝜌 are relevant in estimating certain important physical properties of petroleum products. In this study, gamma – ray absorption technique has been used to determine mass attenuation coefficients and mass energy absorption coefficients of the following petroleum products; Kerosene, Aviation Turbine Kerosene, Gasoline (Petrol) and Gasoil (Diesel). Gamma photon energy of 662 keV from a 30 mCi (137Cs) source was utilised together with NaI (Tl) Scintillation detector and Ludlum ratemeter (Gamma Counter). The Theoretical values of mass attenuation coefficient and the mass energy absorption coefficient of each petroleum products was calculated. Experimental results were compared with theoretical ones showing a good correlation between methods. These attenuation properties can be used to determine some physical parameters of petroleum products such as density and hence check adulterations in petroleum products. The experimental values of 𝜇𝜌 of the petroleum samples range from 0. 0855 to 0.0911 (cm2/g), the theoretical values of 𝜇𝜌 were between 0.0916 and 0.0932(cm2/g) with error deviation from 3% to 7%. The experimental and theoretical mass energy absorption coefficients 𝜇𝑒𝑛𝜌 recorded were in the range of 0.0330 to 0.0352(cm2/g) and 0.0336 to 0.0342 (cm2/g) respectively, having an error deviation between 1% and 3%.