Velp Scientifica
– UDK139 Operating Manual
10004762/B5
119
4) Titration:
after the addition of phenolphthalein indicator (10 drops) titrate by
sodium hydroxide 0,04 N, until pink colour persists.
5) Computation:
the result is obtained by the formula:
mg/l volatile acids (as acetic acid) =
F
x
sample
used
of
ml
6005x1000
x
N
x
NaOH
ml
used
F represents a recovery factor of the distillator used, which is obtained by distilling
known volumes (eg. 10 ml) of acetic acid solution 2000 mg/l and computing:
l
theoretica
NaOH
ml
100
x
used
NaOH
ml
factor
References:
- Lombardo, J.B. (1973).
Improved distillation method for volatile acid analysis
.
Journal Water Pollution Control Federation. 45:1046-1051.
- Buswell, A.M. (1945
). A note on the determination of volatile acids in digester
sludge
. Sewage Works Journal. 20: 845-850.
306