Effect of Chloride Ion on Free Nitrite Ion in Cement

• Published in: International Journal of Corrosion Vol. 2018; no. 2018; pp. 1 - 6
• Main Authors: Yang, Mengna, Dai, Yanhua, Liu, Junzhe, Xing, Xiangwei, Li, Yushun
• Format: Journal Article
• Language: English
• Published: Cairo, Egypt Hindawi Publishing Corporation 01.01.2018; Hindawi; John Wiley & Sons, Inc; Hindawi Limited; Wiley
• Subjects: Adsorption; Analysis; Atomic force microscopy; Cathodic protection; Cement; Cement hydration; Cements; Chloride; Chloride ions; Concrete; Concrete research; Corrosion; Corrosion inhibitors; Curing; Diffraction; Electron microscopy; Erosion; Nitrogen dioxide; Organic chemistry; Quantitative analysis; Ratios; Reinforced concrete; Scanning electron microscopy; X-ray diffraction; X-rays; China
• ISSN: 1687-9325; 1687-9333
• DOI: 10.1155/2018/2940953

This was an experiment in which chloride was externally permeated into cement paste. The influence of Cl- on the content and distribution of free-form NO2- in the cement paste was researched using the chemical quantitative analysis method. The action mechanism was investigated by the micro-means of X-ray diffraction (XRD) and scanning electron microscopy (SEM). The results show that the physical competitive adsorption of Cl- with NO2- on C-S-H and the chemical substitution of Cl- to NO2-AFm caused more free-form NO2- in the cement paste. In the cement paste with chloride salt erosion, the NO2- concentration in the erosion surface was the lowest, and the NO2- concentration reached the highest value at 10mm from the erosion surface. The concentration decreased gradually with the depth from the erosion surface.