An on-line potentiometric sequential injection titration process analyser for the determination of acetic acid.
An on-line potentiometric sequential injection titration process analyser for the determination of acetic acid is proposed. A solution of 0.1 mol L(-1) sodium chloride is used as carrier. Titration is achieved by aspirating acetic acid samples between two strong base-zone volumes into a holding coil and by channelling the stack of well-defined zones with flow reversal through a reaction coil to a potentiometric sensor where the peak widths were measured. A linear relationship between peak width and logarithm of the acid concentration was obtained in the range 1-9 g/100 mL. Vinegar samples were analysed without any sample pre-treatment. The method has a relative standard deviation of 0.4% with a sample frequency of 28 samples per hour. The results revealed good agreement between the proposed sequential injection and an automated batch titration method.
Department of Chemistry, University of Pretoria, South Africa. Koos.vanStaden@chem.up.ac.za
J F
JF
van Staden
Mulalo G
MG
Mashamba
Raluca I
RI
Stefan
D019342:Acetic Acid / Q000032:analysis* / Q000737:chemistry*; D017022:Flow Injection Analysis / Q000379:methods*; D011199:Potentiometry / Q000379:methods*; D015203:Reproducibility of Results; D012972:Sodium Hydroxide; D017186:Titrimetry / Q000379:methods*
D012972:Sodium Hydroxide; D019342:Acetic Acid