raw · papers · ingested 2026-06-19
Composites 'salt inside porous matrix' for adsorption heat transformation: state-of-the-art and new trends
Source: https://academic.oup.com/ijlct/article/7/4/288/653282
Aristov group, Int. J. Low-Carbon Technologies; foundational CSPM review.
Key findings
- Defines CSPM (salt in porous matrix); uptake up to 4x bare silica gel via chemical adsorption.
- Binary LiCl+CaCl2 on zeolite 13X / SAPO-34 reach 5.3x and 4x the bare-matrix uptake.
- CaCl2/LiBr on silica absorb up to 0.75 g/g; adding LiBr to LiCl/silica raises capacity ~5.5%.
- FAILURE MODES: salt solution leaks from pores when operating relative pressure exceeds the impregnating-solution equilibrium pressure -> corrosion of metal parts + non-condensable gas emission.
- Deliquescence: saturated CaCl2 at 20-30 C has relative pressure 0.22 (adsorption must stay below).
- Leakage prevention: choose impregnating concentration below critical C_imp by factor 1.5-2x.
- Pore-blockage ceiling is salt-specific: ZnCl2/AC plateaus at 32 wt% (aggregates block pores) vs CaCl2/AC improving to 70 wt%.
- Cycling: silica composites “slight destruction” to 100 cycles, but long-cycle hydrothermal stability must be verified.
- Mitigations: expanded-graphite consolidation (anti-agglomeration), binary-salt tuning, hydrophobic breathable coatings, cation anchoring.