Solid Sampling Line

DOE-HDBK-3010-94

Appendix B; Production Support Lab

Several types of counting devices are available in the liquid sample line rooms. The most

significant are the simple alpha and gamma scintillation detectors used for measuring

plutonium and americium respectively, and the x-ray fluorescence unit. This unit is

contained in a shielded enclosure in the corner of the room. The unit is constructed so that it

is not physically possible for an operator to get his hands into the path of the primary or

secondary beams, and warning lights are activated in the room and the outside corridor when

the unit is activated. The unit is operated in accordance with ANSI standards in the NBS

111 publication.

3.2.3 S olid S am p lin g L in e

The solid sampling line contains one rack that can hold up to 10 sample vials awaiting

analysis, and 1 metal storage container that can hold up to 5 sample vials awaiting return to

H-1 for recycle into the main process. The glovebox consists of five major stations: (1) the

densitometer station, (2) the preparation/dissolution station, (3) the aliquotting station, (4) the

extraction and drying station, and (5) the titration station.

The densitometer station and the aliquotting station are essentially the same as their

counterparts in the liquid lines. The preparation/dissolution station is the first unique feature

of the solid sampling box. It is necessary because all solids must pass through a liquid phase

before final analysis. Small metal samples are easily dissolved in hydrochloric or nitric

acids. Plutonium fluoride is dissolved in nitric acid with an aluminum complexing agent,

and plutonium peroxide is dissolved in acid containing an oxidizing or reducing agent (i.e.,

permanganate or iodide). Plutonium oxide is normally mixed with potassium pyrosulfate and

fused in a small muffle furnace provided at the station. The resulting solid is easily

dissolved in nitric acid.

The extraction and drying station performs the same operations as the same section does in

the liquid lines as well as one additional major operation. This operation is the extraction of

neptunium from the aqueous americium layer by use of small ion exchange columns made of

laboratory glassware. This operation is conducted on solutions obtained from product metal

samples, with the neptunium obtained being plated out on a stainless steel disc in the same

manner as plutonium.

The titration station is used to dissolve small metal samples of plutonium in hydrochloric

acid. The resulting solution is reduced by the addition of titanium chloride and titrated to an

endpoint with cerric ammonium nitrate solution. This operation is used to determine the

relative purity of the original sample.

Page B-94