Processing kodak motion picture films, module 3 analytical procedures

REAGENTS
Use ACS Reagent Grade reagents unless specified
otherwise.
Polystyrene Sulfonate, (0.1%)
Butyl Acetate
Ferroin Indicator
Sulfuric Acid, H 2 SO 4 , (1.0 N)
Sulfato Cerate, (NH 4 ) 2 Ce(NO 3 ) 6 , (0.05N) standardized to
4 places past the decimal point
Sodium Chloride, NaCl
PROCEDURE
Extraction of the Developing Agent, CD-2, with
Butyl Acetate
1. Pipette 25.0 mL (potentiometric titration) or 50.0 mL
(visual titration) of sample into a 250-mL separatory
funnel (No. 1).
2. Add 5.0 g NaCl to the separatory funnel.
3. Add 2 mL of 0.1% polystyrene sulfonate solution.
Stopper the funnel and mix, by gently swirling or
shaking, until all the salt completely dissolves.
4. Add 50 mL of butyl acetate. Swirl the funnel for 30
seconds. Stopper the funnel, invert and vent through
the stopcock. Shake separatory funnel No. 1,
horizontally, for a few seconds; invert and vent the
funnel through the stopcock. Continue to shake
vigorously for 30 seconds. The funnel should be
vented at least 2 times.
5. Allow the layers to separate. Gently swirling the
funnel will aid breaking up any emulsion at the
aqueous-nonaqueous interface.
6. After separation of the layers occurs, transfer the lower
(aqueous) layer, as completely as possible, including
any emulsion that fails to separate, into another
250-mL separatory funnel (No. 2).
7. Swirl separatory funnel No. 1 and drain any additional
lower (aqueous) layer that separates into separatory
funnel No. 2. Save the top (butyl acetate) layer in
separatory funnel No. 1.
8. Add 50 mL of butyl acetate to separatory funnel No. 2.
Swirl the funnel for 30 seconds. Stopper the funnel;
invert and vent through the stopcock. Shake the funnel
horizontally for a few seconds; invert and vent through
the stopcock. Continue to shake the funnel vigorously
for 30 seconds, venting at least 2 times.
9. After the layers separate, discard the lower (aqueous)
layer as completely as possible. Swirl the funnel and
discard any additional aqueous layer that separates,
taking care not to lose any of the butyl acetate layer.
Discard any emulsion layer that fails to separate.
Note: Additional separation time may be needed for
highly seasoned samples.
10. Transfer the contents of separatory funnel No. 2 (butyl
acetate layer) into funnel No. 1 (which contains the
first butyl acetate layer).
Back-Extraction of the Developing Agent
1. Add 100 mL of 1.0 N sulfuric acid to separatory funnel
No. 2 and swirl, rinsing the inside walls of the funnel.
Save the funnel contents for step 3.
2. Gently swirl separatory funnel No. 1 and discard, as
completely as possible, any lower (aqueous) layer that
separates, taking care not to lose any of the butyl
acetate layer.
3. Transfer the contents of separatory funnel No. 2 into
funnel No. 1.
4. Swirl the funnel for 30 seconds. Stopper the funnel;
invert and vent through the stopcock. Shake the
separatory funnel horizontally for a few seconds;
invert and vent through the stopcock. Continue to
shake vigorously for 30 seconds, venting 2 times.
5. Allow enough time for complete separation of the
phases.
Note: It may take longer for complete separation of the
phases in highly seasoned samples.
6. Transfer the lower (acid) layer from separatory funnel
No. 1 to a 250-mL beaker without losing any of the top
layer.
7. Swirl separatory funnel No. 1 and transfer any
additional lower (acid) layer that separates, as
completely as possible, into the beaker.
4 Processing KODAK Motion Picture Films, Module 3, Analytical Procedures H24.03