Working Procedure of a Best Ph Meter in Textile Factory

Best Ph Meter

This test done by Best Ph Meter for checking the effect of garment on skin. Generally PH standard differ from buyer to buyer but acceptable level is 6 to 8. Take 250 ml distal water in beaker and place it on hot plate. When water is fully boiled (approx. 20 min.), put the testing material (10g). Boil the water for another 10 min. When boil water temp. comes as per room temp. (Around 28 C) then takes the PH reading by Digital Ph Tester or PH paper.

PH MEASUREMENT BY DIGITAL PH METER

• Switch ON the instrument , wait till its warm up
• Adjust the temperature to room temperature using temperature setting knob
• Wash the electrode by DM water
• Dip the electrode in 4 pH buffer solution
• Adjust the reading to 4 by using calibration knob
• Wash the electrode by DM water
• Dip the electrode in 9.2 pH buffer solution
• Adjust the reading to 9.2 by using calibration knob
• Wash the electrode by DM water
• Dip the electrode in 7 pH buffer solution
• Cross check the instrument
• If the reading is 7, the instrument is ready for pH measurement
• Then go to check samples
• Shift once calibrate the instrument, before going to check the samples
• Perform 3 point calibration to cover acid – neutral – alkaline range in above mentioned procedure

BUFFER 4.00 SOLUTION

• Transfer the content of one capsule of buffer 4.00 into a 100ml standard flask through a funnel.
• Add little distilled water to dissolve the chemicals.
• Ensure complete dissolution by shaking.
• Make up the volume to 100ml.
• Transfer this solution to a bottle.
• This solution is buffer pH 4.00.

BUFFER 7.00 SOLUTION

• Transfer the content of one capsule of buffer 7.00 into a 100ml standard flask through a funnel.
• Add little distilled water to dissolve the chemicals.
• Ensure complete dissolution by shaking.
• Make up the volume to 100ml.
• Transfer this solution to a bottle.
• This solution is buffer pH 7.00.

BUFFER 9.20 SOLUTION

• Transfer the content of one capsule of buffer 9.2 into a 100ml standard flask through a funnel.
• Add little distilled water to dissolve the chemicals.
• Ensure complete dissolution by shaking.
• Make up the volume to 100ml.
• Transfer this solution to a bottle.
• This solution is buffer pH 9.2

Digital Ph Tester Report on different chemical

g/l	Eulysin S PH	Benlon 2900 PH	Diapol AB PH	Acetic Acid PH	Ultra Mat	Dinasit AT
0.1	6.13	6.44	6.75	5.95	6.40	6.77
0.15	5.78	6.24	6.67	5.45	6.25	6.58
0.2	5.49	6.02	6.62	5.10	6.01	6.32
0.25	5.20	5.81	6.57	4.84	5.75	5.89
0.3	4.96	5.46	6.48	4.65	5.49	5.31
0.35	4.79	4.88	6.42	4.53	5.17	4.84
0.4	4.64	4.41	6.35	4.44	4.85	4.58
0.45	4.55	4.16	6.29	4.36	4.62	4.51
0.5	4.44	3.97	6.23	4.30	4.40	4.45
0.55	4.36	3.89	6.16	4.24	4.29	4.32
0.6	4.31	3.81	6.08	4.19	4.16	4.18
0.65	4.26	3.73	6.01	4.14	4.07	4.04
0.7	4.20	3.69	5.91	4.12	3.98	3.91
0.75	4.15	3.62	5.82	4.08	3.92	3.83
0.8	4.11	3.57	5.68	4.03	3.86	3.78
0.85	4.07	3.53	5.55	4.01	3.82	3.7
0.9	4.03	3.49	5.35	3.99	3.78	3.62
0.95	4.01	3.46	5.14	3.95	3.74	3.56
1.0	3.97	3.43	4.93	3.93	3.70	3.49

Some Chemical Test

Chemical: To assess its quality it is use in sample/bulk production and found the result okay. (not okay)

Dyestuff: For new dyestuff we prepare self-shade and check its fastness (rubbing & washing) properties and the dyestuff meet our minimum quality standard.

Acetic acid, caustic, hydrogen per oxide: After titration we found its strength (45%). It is meet (not) our minimum quality standard (95% ±5).

Hydrogen Peroxide (H₂O₂) MW 34.02

Purpose of The test: Determine of the strength of the Hydrogen Peroxide

Method: 1. Titration with standard Permanganate

Reagents: A. Potassium Permanganate 0.1 N. B. Sulfuric Acid 1:4

Procedure: Take a weighed sample such that there are no more than 0.06 gm of H₂O₂  present. Dilute with 50 ml of distilled water and 10 ml of 1:4 Sulfuric Acid. Titrate to the permanent pink coloration with 0.1 KMnO_4. Calculate as H₂O₂

Chemical Reaction: 5H₂O₂ + 2KMnO₄ + 4H₂SO₄ = 2KHSO₄ +5O₂ +8H₂O

Solution Preparation:

1. 25cc H2SO4 + 75 cc Water = 1:4 Sulfuric Acid

N.B: When we determine the strength the Hydroge Peroxide 50%, result should be within 45 to 50%.

Sodium Hydroxide (NaOH)

Purpose: Determine the strength of Sodium Hydroxide.

Reagents: Phenolphthalein indicator 0.1% alcohol, Methyl Orange indicator 0.1% in alcohol. Hydrochloric Acid 1.0N.

Procedure: A sample liquid or flakes of approximately 10 grams in accurately weighed and made up to 1 litre with carbonate free distilled water. Fifty ml. aliquots of this solution to which are added 2 drops of phenolphthalein are titrated first to the phenolphthalein end point. Two drops of methyl orange indicator are added and the titration is carried on the methyl orange end point.

The acid consumed to the phenolphthalein end point neutralizes all of the Hydroxyl and half of the carbonates. The acid added from the phenolphthalein to the methyl orange end points neutralizes the remaining half of the carbonates.

Report as % NaOH and Na₂CO₃ 

1. A = Vol. from to phenolphthalein end point
2. B= Vol. from phenolphthalein to the methyl orange end point

Calculation:

N.B= Result, within 90% To 100 %  is normally required.

Concentration Hydrochloric Acid

Apparatus or Equipment Used:

1. Burette
2. Pipette
3. Beaker
4. Balance

Frequency:                                 Every New lot as and when required

Method:                                      Titration with standard base (Sodium Hydroxide)

Reagent:                                                 Sodium Hydroxide 0.1 (N), Phenolphthalein indicator.

Procedure:

1. Take 10ml Hcl and weigh it in gm (Usually it is 10.96gm). Make 1 litre solution in a volumetric flask.
2. Take 25ml solution, add Phenolphthalein indicator.
3. Titrate by 0.1 (N) caustic soda. ( Usually It requires 26-29 Cc to be titrated)

Result :

Performance Standard: 37% or as required.

Formic acid Test ( Bcl2.2H2O test for the presence of H2SO4 as impurities

Apparatus or Equipment:

1. Burette
2. Pipette
3. Beaker
4. Balance

Frequency: Every new lot and also as and when required.

Method: Titration with standard base (Sodium Hydroxide)

Reagent :  Sodium Hydroxide 1 (N), Phenolphthalein Indicator.

Procedure:

1. 6 gm formic acid is added in 100ml water
2. Take 10ml solution in a conical flask. Add 2-3 drops of Phenolphthalein indicator.
3. Titrate by 1(N) caustic Soda
4. Burette Reading × 10

Performance Standard: 80 to 100% or as required.

5. Glauber’s Salt ( Silver Nitrate Test for the presence of — as impurities.

Apparatus of Equipment:

1. Burette
2. Pipette
3. Beaker
4. Balance

Frequency : Every new lot and also as and when required.

Method: Na

Reagent: Na

Procedure:

1. Take the beaker, dry it and take the weight. (Example:X)
2. Take 10gm G.Salt in 50 ml Distilled Water and make the solution.
3. Filter the solution
4. Take the solution in the beaker and evaporate it.
5. Take the weight of the beaker (Example-Y)

Result:

{(y-x)-10}×10

Performance Standard : 90-100%

Dr. Pertus, Chemist, Sent josef laboratory ltd. Srilanka

Conclusion

End of Best Ph Meter artivcle