Benzoic Acid Raw Material Standard Analytical Procedure is an organic aromatic monocarboxylic acid. It can be synthesized by the cobalt or manganese catalyzed atmospheric oxidation of toluene.
Benzoic Acid Raw Material Standard Analytical Procedure reacts with hydrogenating reagents to afford hexahydrobenzoic acid. The thermal decomposition of the product in the presence of lime or alkali produces benzene and carbon dioxide.
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Analyst |
Quality Control Manager |
Quality Assurance Manager |
General Manager Plant |
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1.0 Purpose
1.1 To ensure the quality of incoming raw material of Benzoic Acid.
2.0 Scope
2.1 It is applicable for the analysis of Benzoic Acid in the quality control department.
3.0 Responsibility
3.1 Quality Control Manager
3.2 Assist. Q.C. Manager
3.3 Q.C Analyst
4.0 Abbreviations
4.1 SAP: Standard Analytical Procedure
4.2 QC: Quality control
5.0 Procedure
5.1 Equipment/Apparatus
a) Analytical balance
b) Nessler Cylinder
c) Melting point apparatus
d) Glass Tests Tubes
e) Silica Crucible
f) Glass beakers
g) Burette 50 ml
h) Titration Flask
5.2 Chemicals/Reagents
Chemicals
- Distilled water
- Ethanol (96%)
- Chloroform
- Sulphuric Acid
- Acetone
- Hydrochloric Acid
Reagents
- Acetate buffer pH 3.5
- Thioacetamide reagent
- Sulphuric Acid 1M
- Potassium permanganate 0.02M
- Sodium hydroxide 0.1M solution
- 0.1N Sodium Hydroxide solution
- Phenol red solution
- Ferric Chloride Solution R1
5.3 Physical Analysis
a) Test of Physical Form:
Check the sample and confirm its physical form; it should be crystalline powder or crystals.
b) Test of Colour:
Confirm the colour of the material; it should be white, almost white or colorless.
c) Test of solubility:
- Water: Slightly soluble
- Boiling Water: Soluble
- Ethanol (96%): freely soluble
- Fatty oils: freely soluble
e) Appearance of solution:
a) Weigh accurately 5 gm of sample, dissolve in ethanol (96%) and make the volume upto 100 ml with same solvent.
b) Fill Nessler cylinder of 15 – 20 mm in internal diameter to the depth of 40 mm.
c) Take the same type of Nessler’s cylinder and fill the ethanol (96%) upto 40 mm depth this cylinder is taken as blank. Observe both cylinders against black background by viewing in diffused daylight down the nautical axes of cylinders.
It should be clear and colourless.
f) Test of Melting Point:
a) Dry the finely powdered substance at 105oC for 1 hour.
b) Transfer a sufficient portion to a dry capillary tube to form a compact column of 4 – 6 mm in height.
c) Note the melting point by observing the temperature at which last solid particle passes into liquid phase.
It should be 121oC – 124oC.
g) Carbonisable substances:
Dissolve 0.5 gm, with shaking, in 5 ml of sulphuric acid and allow standing 5 minutes. Any colour produced in the solution is not more intense than that of reference solution Y5.
i) Oxidizable substance:
Dissolve 0.2 g in 10 ml of boiling water, cool, shake and filter. To the filtrate add 1 ml of 1M sulphuric acid and 0.2 ml of 0.02M potassium permanganate and allow standing for 5 minutes. The solution remains pink.
Limit Tests:
a) Heavy Metals
Sample Preparation
a) Take 12 ml of sample 5.0 % w/v solution in ethanol in a test tube.
b) Add 2 ml of acetate buffer pH 3.5 and mix.
c) Add 1.2 ml of thioacetamide reagent mix immediately and allow to stand for two minutes.
Standard Preparation
a) Take mixture of 5 ml of lead standard solution (1 ppm) and 5 ml of ethanol (96%) that will be (10 ppm Pb), is a test tube.
b) Follow as in (b) and (c)
Blank
10 ml of ethanol add 2ml of acetate buffer pH 3.5. Add 1.2 ml of thioacetamide reagent mix immediately and allow to stand for two minutes.
Observations
a) Any brown colour produced in sample is not more intense than standard.
b) The standard solution exhibits slightly brown colour when compared to blank.
5.4 Chemical Analysis:
Identification Test of Benzoic Acid:
A) Melting point
a) Dry the finely powdered substance at 105oC for 1 hour.
b) Transfer a sufficient portion to a dry capillary tube to form a compact column of 4 – 6 mm in height.
c) Note the melting point by observing the temperature at which last solid particle passes into liquid phase.
That should be between 121oC to 124oC
B) Reaction of benzoates
a) To 1 ml of a 10% w/v neutral solution of the substance being examined or to 1 ml of the prescribed solution add 0.5 ml of iron (III) chloride solution R1. A dull yellow precipitate is produced which is soluble in ether.
b) Moisten 0.2 g of the substance being examined, treated as prescribed if necessary, with 0.2 to 0.3 ml of sulphuric acid and gently warm the bottom of the tube. A white sublimate is deposited on the inner wall of the tube.
c) To 0.5 g of the substance being examined dissolved in 10 ml of water or to 10 ml of the prescribed solution add 0.5 ml of hydrochloric acid. The melting point of the precipitate, after recrystallisation from water and drying at a pressure of 2 kPa, is 120° to 124°.
Contents of Benzoic Acid:
Analysis Procedure:
a) Dissolve 0.2 gm in 20 ml of ethanol (96%) in a titration flask.
b) Titrate with 0.1 M sodium Hydroxide VS using phenol red solution as indicator.
c) End point will be violet red.
Observation:
a) Volume of 0.1M NaOH VS consumed = P
b) Record the reading
Calculations:
Calculate the contents of Benzoic Acid as follows:
Factor: Each ml of 0.1M NaOH VS is equivalent to 0.01221 g of Benzoic Acid.
0.01221 x P / 0.1 x 100 = S
Limit: The contents of Benzoic Acid should be 99.0% to 100.5%.
6.0 Quality Record(s)/Form(s):
6.1 The following Quality Records shall be generated and managed in accordance with the Procedure for Control of Company Quality Records.
7.0 Reference:
BP 2015