Sustainable carbon capture using porous geopolymer-derived zeolite 4 a monoliths: Low-cost, high-performance composite sorbent

A GD-Z4 A (geopolymer-derived Zeolite 4 A monolith) was synthesized via a one-pot, low-temperature method as a sustainable sorbent for CO₂ capture. Canola oil and hydrogen peroxide were employed as dual porogens to create hierarchical porosity without requiring hydrothermal treatment. X-ray diffraction and electron microscopy confirmed zeolite crystallization and well-distributed pore networks. The composite achieved a CO₂ uptake of 2.43 mmol g −1 by dynamic vapor sorption (DVS), comparable to activated carbon (2.59 mmol g −1 ) and SAPO-34-geopolymer composites (2.41 mmol g −1 ). Thermogravimetric analysis indicated thermal stability up to 300 °C, with reversible adsorption-desorption under mild regeneration conditions. Mechanical testing showed a compressive strength of 32.0 ± 1.6 MPa, confirming that the porous monolith retained structural integrity suitable for handling and shaped-adsorbent development. Compared to conventional adsorbents, the composite combines scalable synthesis, robust mechanical properties, and environmentally benign processing. This work establishes a cost-effective route to hierarchically porous zeolite-based materials for industrial carbon capture and storage applications. • One-pot low-temperature route crystallizes zeolite 4 A without hydrothermal steps. • Canola oil and H₂O₂ create hierarchical pores using benign, available porogens. • Monolithic composite balances CO₂ uptake and strength for shaping and handling. • Regeneration assessed at defined CO₂ partial pressures and temperatures.