Preliminary Investigation of Pretreatment Methods for Liquid Scintillation Measurements of Environmental Water Samples Using Ion Exchange Resins

This paper presents an evaluation of a rapid pretreatment method for tritium analysis, that uses ion exchange resins (the batch method). The standard water samples were prepared with river water collected in Okinawa, Japan. Powdex resin was used in this study, which is an ion exchange resins in the form of powder beads. First, 100 mL of the standard sample was stirred with the cation exchange (PCH) and anion exchange (PAO) resins, as well as with activated carbon. To determine the optimal stirring time, we tested stirring times of 5, 10, 20 and 30 min. Additionally, to determine a suitable amount of ion exchange resin for environmental water samples, variations in the amount of resin and activated carbon were tested. Under the conditions of Experiment-3 (0.3 g, 0.3 g and 0.6 g of PCH, PAO and activated carbon, respectively) and with a stirring time of 5 min, electrical conductivity values of less than 1 mSm^ were achieved. These results demonstrate the effectiveness of the removal of impurities in the sample water by ion exchange resins and confirm that such an effect can be achieved during a short period of time (i.e., in 5 min)

Preliminary Investigation of Pretreatment Methods for Liquid Scintillation Measurements of Environmental Water Samples Using Ion Exchange Resins

This paper presents an evaluation of a rapid pretreatment method for tritium analysis, that uses ion exchange resins (the batch method). The standard water samples were prepared with river water collected in Okinawa, Japan. Powdex resin was used in this study, which is an ion exchange resins in the form of powder beads. First, 100 mL of the standard sample was stirred with the cation exchange (PCH) and anion exchange (PAO) resins, as well as with activated carbon. To determine the optimal stirring time, we tested stirring times of 5, 10, 20 and 30 min. Additionally, to determine a suitable amount of ion exchange resin for environmental water samples, variations in the amount of resin and activated carbon were tested. Under the conditions of Experiment-3 (0.3 g, 0.3 g and 0.6 g of PCH, PAO and activated carbon, respectively) and with a stirring time of 5 min, electrical conductivity values of less than 1 mSm−1 were achieved. These results demonstrate the effectiveness of the removal of impurities in the sample water by ion exchange resins and confirm that such an effect can be achieved during a short period of time (i.e., in 5 min)

Simple Pretreatment Method for Tritium Measurement in Environmental Water Samples using a Liquid Scintillation Counter

The aim of this study is to evaluate quantitatively the effectiveness of the ion exchange resins and activated carbon in tritium measurement. A standard water sample was adjusted to a tritium concentration of 5 Bq L−1. This sample was stirred with the cation exchange (PCH) and anion exchange (PAO) resins and activated carbon. After stirring the samples, the supernatant in each sample was filtered through 0.45 μm membrane filters. The electrical conductivity in an experimental condition, where the amounts of PCH, PAO, and activated carbon were 0.3 g, 0.3 g, and 0.6 g, respectively, was lower than that of the sample treated by the distillation method. The distillation method requires approximately 12 h to process; however, the same level of results was achieved in 5 min. The tritium concentration in each experiment was within the standard deviation. These results suggested that proposed batch method involving ion exchange resins and activated carbon had negligible effect on tritium measurement. The ion concentration and the total organic carbon for the samples were decreased in 5 min. These results demonstrate the effectiveness of the impurity removal from the sample water by ion exchange resins