Ceramics-Silikáty 45, (3) 81 - 88 (2001)

Corrosion of hardened paste of geopolymeric cements in solutions of nitric acid starts by a leaching process in which the soluble contents of the material (i.e. sodium and calcium) are depleted and replaced by H⁺ or H₃O⁺ ions from solution along with an attack by acidic protons on polymeric Si-O-Al bonds (to be discussed in Part 2) resulting in the formation of a partially dealkalized and decalcified Si-, Al-rich residue.