ISO 13163:2013 pdf free

ISO 13163:2013 pdf free.Water quality一Lead-210一Test method using liquid scintillation counting
The preparation of the sample is to be adapted according to the detection limit required. Usually, the sample volume ranges from 0,51to 1,51.
If necessary, perform filtration before acidification using a filtering membrane of mesh size 0,45 μm.It is recommended that a single-use filtration device be used.
Acidify the filtrate with concentrated nitric acid and ensure that the pH of the sample filtrate is less than or equal to 2.
Acidification of the water sample minimizes the loss of radioactive material from the solution by adsorption. If filtration of the sample is required, acidification is performed afterwards; otherwise, radioactive material already adsorbed on to the particulate material can be desorbed.
NOTE For raw water, the percolation of such water sample through the resin can be reduced depending on its suspended material and salinity content.
It is recommended that all operations be performed under a ventilated hood.
Add a known quantity of lead standard solution (e.g. corresponding to approximately 1 mg to 10 mg of Pb) to the sample for the determination of the chemical yield and mix well.
The concentrations of Ca, Ba, K, Na, and Sr in the sample can impact the chemical yield (see Clause 8)
An Fe(III) co-precipitation allows the greater part of alkaline and alkaline-earth elements to be eliminated. Add 10 mg to 20 mg of the FeC(II) solution to the sample. Mix to homogenize and warm the solution to approximately 50 °C to 60°C.
Add concentrated ammonia to pH about 9: Fe(OH)3 precipitates.
Allow the solution to settle and cool for at least 2 h, and then separate both phases by filtration or by centrifugation.
The Fe(OH)3 precipitate is isolated and dissolved in a minimum volume of 2 mol-1 HCI (for method 1) or 1 mol-l-1 HNO3 (for method 2). A small amount of acid (about 5 ml to 10 ml) should be used.
The preconcentration can be also performed with a sulfonic-type cation exchange resin (References [17] [25]). An example of a preconcentration procedure is described hereafter.
If suspended material is present, filter the sample (approximately 0,2 kg) under vacuum (0,45 μm). Acidify with nitric acid, approximately to a concentration of 0,01 mol:I-1 (0,2 ml of concentrated nitric acid in 0,2 kg sample).ISO 13163 pdf download.