Adsorption of Hg2+ on cyclophosphazene and triazine moieties based inorganic-organic hybrid nanoporous materials synthesized by microwave assisted method

[Display omitted] •The synthesized adsorbent CTHM-2 used as an efficient and suitable adsorbent for Hg2+ removal.•The adsorbent (CTHM-2) is suitable for Hg2+ removal from aqueous solution in both high (500 ppm) and low (2 ppm) concentration of Hg2+ solution.•A mixed matrix membrane (MMM) fabricated using CTHM-2 with 29.6 cm2 effective area has efficiently adsorbed Hg2+ via dynamic adsorption process with flux of 16 LMH (L m−2h−1) leaves the concentration up to the permissible limit by WHO.•The MMM can treat 5 L of contaminated Hg2+ solution up to 8 h. The cyclophosphazene and triazine moieties based inorganic–organic hybrid nanoporous materials (CTHMs) have been synthesized. The material CTHM-2 synthesized by microwave-assisted method at 120 °C with microwave power of 400 W for 60 min possess the BET specific surface area of 95 m2/g. The CTHM-2 could reversibly adsorb Hg2+ ions from its aqueous solution of concentration 2 ppm of Hg2+ solution leaving behind a concentration of Hg2+ < 1 ppb (maximum permissible limit of the USEPA, BIS, and WHO in drinking water) in 90 min at pH of 6. A maximum adsorption capacity of 774 mg g−1 was estimated using a solution of 500 ppm. The adsorbent works well both at low (2 ppm) and high (500 ppm) initial Hg2+ concentrations. A mixed matrix membrane (MMM) prepared using CTHM-2 is capable of achieving the acceptable Hg2+ limit (