2.3. Cadmium reductor
The reductor column is constructed of Pyrex glass of
10.0 cm length and 1.5 cm diameter, sealed at its upper
end to 5 cm long and 3 cm bore tubing. At its lower
end the column is fused into a tube of 0.4 cm internal
diameter ending with a tap. Cadmium filings (200 g)
prepared by filing cadmium sticks with a second-cut
hand file, were amalgamated by stirring with 100 ml
of 1% (w/v) mercury(II) chloride solution for 10 min.
After settling, the supernatant liquid was decanted and
the amalgamated filings were washed several times
with water until the supernatant became clear. The
filings were stored under water.