Resistance to Chemical Attack of Hydrochloric Acid (HCl)

Three cubes with side of 50 mm were used for each mix in performing the test for resistance to chemical attack of hydrochloric acid. The cubes were first dried in an oven at 90 ◦C until constant mass was reached, and then they were weighed. Afterwards, they were introduced in a HCl solution of 18% concentration (Figure 2a) for 10 days. This concentration level has been chosen in order to perform the test in a shorten period and to subject the mixes to an aggressive action of this acid. After a period of 10 days, the cubes were washed with clean water and brushed for the removal all loose particles (Figure 2b) and dried out in the oven at 90 ◦C till the constant mass was attained. Finally, the specimens were weighed. The resistance evaluation was performed by determining the average relative mass loss.
