Synthesis of zeolite NaX based on fly ash: Mechanism of metal impurity retention and utilisation to promote CO(2) capture efficiency.

Fly ash-derived zeolite NaX with retained metal impurities achieves a 4.63 mmol/g CO2 adsorption capacity, significantly enhancing carbon capture efficiency in steel industry gases.

• Why it matters: Efficient, low-cost adsorbents are urgently needed for capturing CO2 from blast furnace gases to reduce industrial emissions and promote sustainable steel production.
• What they did: The study synthesized zeolite NaX from fly ash by retaining metal impurities (Fe, Ca, Ti) through an impurity retention strategy, analyzing its structure and adsorption performance.
• The result: The resulting ZZ-NaX zeolite exhibits increased surface area, micropore content, and alkaline sites, achieving high CO2 selectivity (103.82 for CO2/CO) and no N2 adsorption, enabling effective carbon capture.