Surface passivation method of geopolymers and alkali activated materials

摘要

In the present invention, there is described a method of surface passivation of geopolymeric and alkali activated materials prepared with the use of sodium, potassium, lithium or mixed hydroxide or water glass by their submerging into a solution and exposing to the action of hydrogen fluoride or vapors of a salt thereof or hexafluorosilicic acid or salts thereof. An insoluble layer being formed on the material surface increases resistance to water, reduces tendency to the formation of efflorescence and hygroscopicity, reduces strong alkaline pH value as well as extractability of matters integrated in material structure.