Emerging Science Journal
|
Vol. 3, No. 2
Page | 103
neck by using pipettes.
Then the system was operated, while the stirrer was adjusted to
appropriate speed and the
temperature was raised, which was maintained between 100-120
o
C for two hours. After that the system was stopped
and
cooled slowly,
then placed in ice path, 0.12 moles of Formaldehyde
was added by using pipettes, a fizzing and
bubbling were occurred, the temperature was cooled to 35
o
C then below 22
o
C by stirring with glass rod. Stirring was
continued until a viscose solid mass was obtained. The product was left overnight. pH was examined by using indicator
paper and NaOH solution drops were added until over saturation was reached to high pH, a few drops of H
2
SO
4
was
added for equilibrium reach until pH=7.
2-5-1- Preparation of Sawdust for Extraction
Sawdust was obtained from the local timber mill and shifted through the sieve having mesh size of 1mm and dried
in an oven at temperature of 105
o
C during 1-2 days until obtained constant weight. Saw dust sample was boiled with
hot water during 4 hrs. and filtered to remove the water soluble matters such as tannins, gums, sugars and colorants.
Solid residue was dried in oven at 105
o
C during 1-2 days until achieved constant weight.
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