Bast Fibre composition
Cellulose Content
Calculation
Cellulose Content (%) = 100 – (Wax Content + Water Soluble matter + Pectin + Hemicellulose Content + Lignin Content)
Wax Content
Apparatus
• Drying oven – 105° C
• Weighing Balance
• Flat RB flask-250ml
• Soxhlet Extractors- 250 ml
• Desiccators
• Thimbles
Reagent
• Benzene Ethanol (2:1)
Procedure
• Dry the Flat RB flask for half an hour at 105° C. cool for about 20 min in Desiccators and weight. Weight 5 gm of sample. Place the sample in a thimble in a soxhlet extractor with Benzene Ethanol (2:1) solvent. Siphons at least six times per hour for three hours. Evaporate the extract carefully to dryness in the RB flask on a stream bath. Further dry the RB flask in the drying oven at 105° C to constant mass. Cool in a desiccators and weight.
Calculation
Wax content (%) = (c-b)*100/ a
Where
a mass of sample
b Oven dry-mass of Flat RB flask
c Oven dry-mass of Flat RB flask with exact
Lignin Content
Apparatus
• Drying oven – it shall be capable of maintaining a temp of 105° C ± 3° C
• Weighing Balance- Capable of weighing Accuracy of 0.0002 g
• Conical flask-500ml
• Reflux Condenser
• Desiccators
• Sieve
Reagent
• 72 % Sulfuric Acid solution
Procedure
• Take Sample wax-free weighing about 1 g. Dry the sample in oven at 105° C ± 3° C for 30 min. cool in a Desiccators and weight them sample (W). Treat the weighted out sample taken in a conical flask with 30 ml of 72 % sulfuric acid solution waiting for 24h. Add 300 ml distilled water and boil the solution for 1 h using Reflux condenser. Remove Reflux condenser and Cool the solution at Room temperature. Filter the content of the flask through a sieve. Wash the residue on the filter sieve with hot distilled water and finally normal distilled water. Dry the residue in the drying oven at 105° C to constant weight. Cool in desiccators and weight them (W1)
Calculation
Lignin content (%) = W1 * 100 / W
Where
W – Original mass of sample
W1 – Oven dry-mass of residue
Water Soluble Matter
Apparatus
• Drying oven – it shall be capable of maintaining a temp of 105° C ± 3° C
• Weighing Balance- Capable of weighing Accuracy of 0.0002 g
• Conical flask-250ml
• Reflux Condenser
• Desiccators
• Sieve
Reagent
• Water
Procedure
Take wax content residue. Dry the sample in oven at 105° C ± 3° C for 30 min. cool in a Desiccators and weight them sample (W). Treat the weighted out sample taken in a conical flask with 150 ml distilled water and boil the solution for 1 hour, changing water, then boiling for 2 hour using Reflux condenser. Remove Reflux condenser and Cool the solution at Room temperature. Filter the content of the flask through a sieve. Wash the residue on the filter sieve with hot distilled water and finally normal distilled water. Dry the residue in the drying oven at 105° C to constant weight. Cool in desiccators and weight them (W1)
Calculation
Water Soluble matter (%) = (W – W1) * 100 / W
Where
W – Original mass of sample
W1 – Oven dry-mass of residue
Pectin
Apparatus
• Drying oven – it shall be capable of maintaining a temp of 105° C ± 3° C
• Weighing Balance- Capable of weighing Accuracy of 0.0002 g
• Conical flask-250ml
• Reflux Condenser
• Desiccators
• Sieve
Reagent
• Ammonium Oxalate ( 5 g/L ) solution
Procedure
• Take water soluble matter residue. Dry the sample in oven at 105° C ± 3° C for 30 min. cool in a Desiccators and weight them sample (W). Treat the weighted out sample taken in a conical flask with 150 ml Ammonium Oxalate solution and boil the solution for 3 hour using Reflux condenser. Remove Reflux condenser and Cool the solution at Room temperature. Filter the content of the flask through a sieve. Wash the residue on the filter sieve with hot distilled water and finally normal distilled water. Dry the residue in the drying oven at 105° C to constant weight. Cool in desiccators and weight them (W1)
Calculation
Pectin content (%) = (W – W1) * 100 / W
Where
W – Original mass of sample
W1 – Oven dry-mass of residue
Hemicellulose Content
Apparatus
• Drying oven – it shall be capable of maintaining a temp of 105° C ± 3° C
• Weighing Balance- Capable of weighing Accuracy of 0.0002 g
• Conical flask-250ml
• Reflux Condenser
• Desiccators
• Sieve
Reagent
• NaoH ( 20 g/L ) solution
Procedure
• Take Pectin Content residue. Dry the sample in oven at 105° C ± 3° C for 30 min. cool in a Desiccators and weight them sample (W). Treat the weighted out sample taken in a conical flask with 150 ml NaoH (20 g/L ) solution and boil the solution for 3 hour using Reflux condenser. Remove Reflux condenser and Cool the solution at Room temperature. Filter the content of the flask through a sieve. Wash the residue on the filter sieve with hot distilled water and finally normal distilled water. Dry the residue in the drying oven at 105° C to constant weight. Cool in desiccators and weight them (W1)
Calculation
Hemicellulose Content (%) = (W – W1) * 100 / W
Where
W – Original mass of sample
W1 – Oven dry-mass of residue
Reference – GB/T 5889-1986 Method of quantities analysis of ramie chemical Components