Conditioning of disused Ra-226 radioactive sealed sources in Egypt

The present work describes the technical information on issues associated with the management of disused Ra-226 radioactive sources. The different settings needed to condition these sources in stainless steel capsules, working area setup, packaging preparation, Ra-226 source characterization, capsule welding, leakage test and data information are completely described. The radium sources addressed in the present work are mainly those which have been used in medicine and for industrial applications, in the form of sealed radiation sources. In Egypt hospitals are among the largest users of sealed radium radioactive sources which are mostly used for brachytherapy. The inventory of radium sources in large hospitals could be in the hundreds. There is a real risk that sources may be lost or mishandled, if very restricted procedures are not followed. An additional problem with these sources is that they are often leaking, due to internal overpressure. The small size of the sources, portability and high apparent value (due to the materials of encapsulation) increase the risk of theft

Removal of Cobalt-60 and Caesium-134 Ions from Contaminated Solutions by Sorption Using Activated Carbon

Date pits (DP) and sawdust (SD) were used as precursors for activated carbons which were prepared by steam pyrolysis of DP and chemical activation of SD, respectively. Surface characterization of both activated carbons was undertaken using the BET method. Adsorption of the radionuclides onto the activated carbon was studied as a function of shaking time, adsorbent mass and pH employing the batch technique. Such adsorption was strongly dependent on the pH of the aqueous medium in contact with the adsorbent, with the removal efficiency attaining a maximum at pH 6. The process was very fast initially, with maximum adsorption being attained within 180 min of initial contact. The adsorption rate could be best fitted by the pseudo-second-order kinetic model. The equilibrium data were analyzed using the Freundlich, Langmuir, Langmuir–Freundlich, Dubinin– Radushkevich, Temkin and Frumkin isotherms. The Langmuir–Freundlich and Frumkin equations were found to best represent the equilibrium data for both radionuclides. The isotherm model constants were determined and used to characterize the distribution of 60 Co and 134 Cs ions onto the adsorbent surfaces and to provide an insight into the affinity of the adsorbents towards these ions

Direct gamma-ray measurement of different radionuclides in the surface water of Suez Canal

The radioactivity levels of naturally-occurring 238U, 232Th, 226Ra and 40K and anthropogenic 137Cs in surface water from eight locations in the Suez Canal have been assessed by gamma-ray spectrometry. The samples were further characterized by determination of the common cations and anions using ion chromatography. A comparison of 137Cs radioactivity levels in surface water from the Suez Canal with those of other sea waters is presented. The radioactivity levels of 238U, 232Th, 226Ra and 40K from sea water are also reported. The effect of total dissolved solids (TDS), chloride, sulphate ion concentrations on the radioactivity levels of 238U, 232Th and 226Ra is discussed

Uses of instrumental neutron activation analysis for elemental investigation of some domestic fertilizers

The neutron irradiation facilities offered by the ET-RR-2 and the HPGe-detection system are used for elemental investigation of three samples of domestic fertilizers. A total of 31 elements have been identified as major and minor concentration values. The Pneumatic Irradiation Transfer Systems (PITS) and the core of the reactor are used for short and long time irradiation. The data obtained for some of the identified elements are compared with the corresponding values obtained by the XRF and the ICP-MS techniques for the same samples. The range of the concentration values of these elements was in between several parts per million (ppm) up to 45 %. A discussion on the elemental concentration values and their biological effect are given