Removal of cyanide using surface-modified Linde Type-A zeolite nanoparticles as an efficient and eco-friendly material

Linde Type-A (LTA) zeolite nanoparticles were synthesized, modified with hexadecyltrimethylammonium bromide, and then used for removal of cyanide from synthetic solution. The synthesized adsorbent was characterized by means of XRD, SEM, FTIR, and BET techniques. Results well revealed that the cyanide adsorption rate increased with increase in solution temperature, and the pseudo second-order model best describe the cyanide adsorption kinetics. The changes in enthalpy (ΔH°) and entropy (ΔS°) were −434 kJ/mol and 5.32 kJ/mol K, respectively, which substantiates the spontaneous and exothermic behaviour of the cyanide uptake by modified LTA zeolite nanoparticles. The experimental isotherm results were best fitted onto the Langmuir monolayer model with a maximum adsorption capacity of 24.09 mg/g; this value is higher than the previously reported values for other adsorbents, and thereby demonstrates that modified LTA zeolite is an efficient adsorbent material for cyanide removal.