Three dimensional calcite consolidation network from calcium ethylene glycol complex solution for stone heritage conservation

Calcium hydroxide-based conservation materials including limewater and nanolime have drawn great attention for calcium carbonate-containing stone heritage conservation, while suffer from low calcium solid content and poor penetrability. Herein, a novel calcium ethylene glycol complex solution (CEGC) is developed by one anti-solvent assisted thermal induced gelation and the following gel-solution conversion strategy. The obtained CEGC solution features high calcium element content (100 mg mL–1) and excellent penetrability (10 mm in Leshan stone), which can invade into the interior of porous weathered Leshan stone heritage and then be carbonatized into stable calcite phase within 72 h at ambient environment. A breathable three-dimensional continuous calcite network attached on the internal surface is formed through the intergrowth of produced calcite particles, producing excellent consolidation performance and improved resistance to freeze–thaw damages. Our work presents a promising calcium hydroxide-based conservation material and contributes to calcium carbonate-containing stone heritage conservation.