Penentuan angka saponifikasi (Saponification Number) dg alat titrino/titroprocessor

Peralatan
Potentiometer = 751 GPD Titrino / Titroprocessor
Electrodes = 6.0232.100 combined pH glass electrode; input 1

Pereaksi
c(HCl) = 1 mol/L; D0

Sample
app. 2 g sunflower oil
25 mL c(KOH) = 0.5 mol/L in ethanol
app. 10-20 mL dist. water

Remarks
· Calculations:

Sapon.No=(C01-EP1)*C02/C00;1;mg/g

Sapon.No = saponification number in mg KOH per g of sample
C01 = consumption of blank sample (12.199 mL)
C02 = mg KOH / 1 mL titrating agent (56.1)

. Answer

Sapon.No = (12.199-5.271) x 56.1 / 2.0224 = 192.2 mg/g

EP1 = 5.271 mL
C00 = 2.0224 g

· Sample preparation:
Weigh out approx. 2 g sample in a round-bottomed flask. Add 25 mL alcoholic KOH solution plus a few boiling beads and allow to boil lightly for at least 30 min. Shake from time to time. Finally rinse the content of the round-bottomed flask into a beaker with a small quantity of dist. water and back titrate the excess of potassium hydroxide with HCl. A blank control sample should be prepared and
treated identically. Enter the blank value as C01.

Literature
· Metrohm Application Bulletin No. 141: Analysis of edible oils and fats.