Recycling furnace slag and fly ash from industrial byproducts to produce slag/ash based zeolite as a new adsorbent material

Sci Prog. 2021 Jul;104(3_suppl):368504221086707. doi: 10.1177/00368504221086707.

Abstract

This study recycling the industrial byproducts of furnace slag and fly ash to produce slag/ash based zeolite. A scanning electron microscopic/energy dispersive X-ray spectroscopic (SEM/EDS) analysis of this zeolite indicates a high SiO2 content of 53.94%, an Al2O3 content of 23.20%, a silicon-to-aluminum ratio of 2.049, a density of 2.88 g/cm3, and a water content of 0.13% while the zeolite appears as a porous crystalline structure. Results of weighing experiments revealed effective adsorption of liquid salad oil and highly volatile organic solvents after reusing the zeolite up to 6 times. When an adsorbed liquid pollutant was desorbed and the heating temperature exceeded 170 °C and 350 °C, the samples exhibited two exothermic reactions, respectively, the mean maximum enthalpy were 0.427 and 0.461 mW, and the mean per gram of accumulated heat were 80.92 and 45.64 J/g. For all samples, the mean maximum loss of mass rate was 9.26%. Analogously, for gaseous pollutants, the samples exhibited an exothermic reaction when the heating temperature exceeded 180 °C; the average maximum enthalpy was 0.395 mW, the average per gram of accumulated heat was 119.60 J/g, and the average maximum loss of mass rate was 4.79%. This slag/ash based zeolite has the advantages of low cost, high thermal stability, reusability, etc., and can be used as a new adsorbent material for indoor ventilation equipment.

Keywords: Recycling; adsorbent material; byproducts; slag/ash based zeolite; thermal analysis experiments.