Selection of Method of Chemical Analysis in Measuring the Salinity of Mineral Materials

Abstract

The article deals with the issue of salt content in brick buildings, which plays an important role in the assessment of the technical condition, in particular of historic buildings. A question has been asked about the selection of the best research method to determine the salinity of mineral materials. To obtain the answer, the authors conducted some tests on ceramic bricks salted with seven types of salt solutions. Research methods such as: spectrophotometry (UV), ion chromatography (High Performance Liquid Chromatography (HPLC)), X-Ray Fluorescence Spectrometry (XRF) and Energy-Dispersive X-Ray Spectroscopy (EDS) were compared. The above methods belong to two groups: the first is based on aqueous extracts and allows the determination of water-soluble salts, and the second concerns testing directly on the sample so that insoluble salts can also be determined. The results tests indicate that the methods based on solid phases (XRF and EDS) give higher salinity values than those based on aqueous extracts (HPLC and UV). The results were also analysed with regard to the type of salt. Larger differences are observed for sulphate salts while chloride salts are characterised by smaller differences. On this basis, it is concluded that the salt content of the material is best assessed using tests that make it possible to recognise the salt in question and its quantity.

Rehabilitation project of Quang Tri Old Citadel in Vietnam: integrated analytical approach from material characterization to architectural heritage valorization

“…In bricks, the concentration of soluble salts was always lower than 1%. As a comparison, in modern bricks, the concentration of soluble ions is approximately 4% (Stryszewska and Dudek, 2020). Therefore, soluble salts are related only to the composition of raw materials, and the masonry is not affected by chemical attacks such as sulfate attack or acid rains (Tittarelli et al , 2008).…”

Atomic spectrometry update: review of advances in the analysis of metals, chemicals and materials

“…A comparison of the suitability of multiple techniques for the determination of salinity in mineral building materials was reported. 147 The paper investigated both aqueous extractable methods with UV and IC, and direct solid analysis with WDXRF and SEM-EDS. Samples were soaked in 10% solutions of chloride and sulfate salts of Ca, K, Mg and Na, then recovered, dried and powdered for either extraction in water or pelletisation for analysis.…”

Study on Deterioration Law and Mechanism of Gray Brick Due to Salt Crystallization

“…As a porous medium material fired from clay, brick is widely used in various ancient buildings and architectural sites. Therefore, it is very important to study the migration and deterioration mechanism of salt in bricks for the preventive protection of ancient brick buildings [15][16][17][18]. Water absorption and salt crystallization are the most common problems and the most serious phenomena leading to the degradation of ancient masonry buildings.…”