Automated continuous-flow titration

An automated continuous titration method is described in which the use of a piston burette as a variable-volume injection device in a flow system allows a continuous-flow titration of a sample solution to be performed similarly to classical batch titrimetric procedures. It is found that by plotting the peak height for each injection versus the titrant volume injected, a titration curve very similar to a batch titrimetric curve can be obtained, and an equivalence volume can be precisely determined. A linear relationship between the logarithm of the equivalence volume and the logarithm of the carrier concentration has been observed over a wide concentration range. The use of reagent is kept to a minimum because titrations are performed by adding only microlitres of reagent. The time required for the titration is comparable to the time consumed by a process titration system. © 1992.