Eco-friendly synthesis from industrial wastewater of Fe and Cu nanoparticles over NaX zeolite and activity in 4-nitrophenol reduction

We deposited Fe and Cu over zeolite NaX (Fe/NaX and Cu/NaX) by adsorption from effluent industrial wastewater. We synthesized the zeolite NaX by the hydrothermal method. 5g of NaX completely adsorbed 350 and 380mg of Fe and Cu from the industrial wastewater, respectively, in 6h. The distribution of Fe and Cu over the NaX was uniform and amounted at 14 and 18mass%, respectively. Fe and Cu modify the morphology of the NaX zeolite: the particle size increased from 9\uce\ubcm to 10\uce\ubcm for the former and decreased to 3\uce\ubcm for the latter. Fe/NaX and Cu/NaX are less crystalline than NaX. BET analysis showed that the specific surface area decreased by 30% and 50% compared to NaX for Fe/NaX and Cu/NaX, but the ratio between meso- and micropores increased by 7 and 13 times, respectively. Fe/NaX and Cu/NaX synthesized by adsorption from industrial wastewater reduced +99% of 4-p-nitrophenol to 4-aminophenol in less than 100s, which is comparable to noble metal