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Hi8201en_r0.4, Moisture determination in shampoo, Method id: hi8201en – Hanna Instruments HI 903 User Manual

Page 187

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Method ID: HI8201EN

Moisture Determination in Shampoo

Titrator Application Methods: General Methods - r. 0.4

Description:

Method for the determination of water in Shampoo.
The results are expressed in % mass and should be
between 70 and 90 %.

Electrode:

HI 76320 Double Platinum Pin Electrode


Reagents:

5 mg/mL One-Component KF Volumetric Titrant

Dry Methanol


Other Accessories:

A clean, dry 1-mL syringe

A clean, dry 18-gauge

, 6” non-coring septum

penetration needle

GL 45-Thread Solvent Bottle

Procedure:

Setup titrator according to the instruction manual.

Press “Select Method” from the main screen. Use
the arrow keys to highlight ‘HI8201EN Moisture in
Shampoo’ and press “Select”.

Install a 5-mL burette filled with 5 mg/mL One-

Component KF Volumetric Titrant and verify that
no air bubbles are present in the burette or tubing.
If necessary prime until all air has been removed
completely.
For the determination of the exact concentration of
the titrant follow HI8001EN 5.0 mg/mL Titrant
Standardization using Liquid Water Standard.

Connect the solvent bottle top assembly to the

bottle of methanol according to the manual.

Prepare the titration vessel according to the

manual. Dispense enough solvent from the solvent
bottle to fill the vessel to the “min” line (about 50
mL).

Press “Start/Stop” to pre-titrate the solvent and the
titration vessel moisture. Allow the background
drift rate to stabilize before proceeding to the next
step.

Fill the syringe and needle with the sample.

Weigh the syringe, needle and shampoo.

Press “Start Analysis”. You will be prompted to
enter the sample size.

Dispense 0.0150 g to 0.0200 g of shampoo into

the titration vessel through the septum using the
needle. Pay attention not to get any sample on
the electrode or beaker walls. If necessary swirl
the titration vessel by hand.

Clear the needle of residual sample by intaking a

small volume of air from the titration vessel. If a
“hanging drop” of sample is seen on the end of the
needle, dip the end of the needle briefly in the
solvent.

Remove the needle from the titration vessel and

weigh the syringe again in order to determine the

added sample mass (by difference of the two
measurements.)

Use the numeric keypad to enter the exact weight

and press “Enter” to start the analysis.

At the end of the titration the “Sample Analysis
Result

” screen is displayed. The results are

expressed in % mass of water.


Method Parameters:

Name:

Moisture in Shampoo

Method Revision:

1.0

Type:

Sample Analysis

Predispensing Amount:

40 %

Pre-Analysis Stir Time:

15 Sec

Stirring Speed:

900 RPM

Stirbar Type:

Medium

Drift Entry:

Automatic

Solvent:

Methanol

Sample Parameters:

Sample Determ.:

Normal

Sample Name:

Shampoo

Sample Type:

Mass

Sample Size:

0.0200 g

Titrant:

Composite 5

Titrant Type:

One Component

Nominal Titrant Conc.:

5.0000 mg/mL

Std. Titrant Conc.:

5.0000 mg/mL

Date/Time:

Jan 1, 2011 12:00

Titrant Age Reminder:

2d:00h:00m

Control Parameters:

Start Mode:

Normal

Standby Mode:

Enabled

Standby Duration:

720 minutes

Imposed Current:

20 uA

Minimum Dose:

0.5000 uL

Maximum Dose:

20.0000 uL

Timed Increment:

1 second

End Point Value:

180.0 mV

Signal Averaging:

3 Readings

Flow Rate:

10.0 mL/min

Termination Parameters:

Maximum Duration:

600 sec

Maximum Titrant Volume:

10.0000 mL

Term. Criterion:

Relative Drift

Relative Drift:

10.0 ug/min

Result Unit:

%

Calculations:

Titrant units:

mg/mL

Titrant volume consumed:

V (mL)

Final results units:

% Mass

Titrant concentration:

5.0000 mg/mL

Sample mass:

0.0200 g