Ion chromatography of soluble salts

The determination of the penetration profile of chloride ions is carried out following an alternative method to UNI 9944:1992, i.e. ion chromatography. The method is based on the simultaneous determination of anionic species by ion chromatography. This technique is based on the separation of analytes using an anion exchange column based on their affinity for the stationary phase. The eluent, containing the separated analytes, passes then through a post-column chemical derivatization device called a suppressor which, by exchanging protons with the mobile phase, has the aim of lowering the background conductivity of the eluent, by forming the weak acid conjugated, and to enhance the analyte signal, which is detected using an in-line conductivity meter. The recognition of the analytes is carried out by comparing the retention time of the sample peaks with the retention time of reference solutions. The concentration is determined by comparing the area of ​​the peak with the calibration curve of the analyte constructed using a series of reference solutions at different concentrations. Such analyses return a percentage value of the presence of chlorides with reference to the assumed weight of the concrete.
Reference standards: UNI EN 206:2021; UNI 11104:2016; UNI EN 1504.