Utilization of metallurgical slag with presence of novel CaO-MgO-SiO2-Al2O3 as a composite sorbent for wastewater treatment contaminated by cerium

The cations of metals are the major pollutants of the lithosphere. Accumulation of cerium in natural water resources might cause serious environmental issue. Another aspect is accumulation of metallurgical slag waste. The metallurgical slag located near Chelyabinsk city in Russia was studied as a potential raw material for preparation of powder and granular calcium magnesium aluminum silicate (CaO-MgO-SiO2-Al2O3) composite sorbents capable to immobilize cerium (Ce3+) ions. Aqueous solutions with a high concentration of Ce3+ ions (1000 mg/L) were applied in sorption experiments. The migration characteristics were studied for calcium (Ca2+), magnesium (Mg2+), silicon (Si4+) and aluminum (Al3+) ions. The degree of Ce3+ ions removal for 24 h reached 93.36% for powdered and 99.98% for granular sorbents. The interaction of sorbents with sorbate was followed by the opposite transition of Ca2+ and Mg2+ ions from sorbent matrix into aqueous solution. The desorption process was investigated in distilled water. The results of study indicated a high degree of irreversible sorption of Ce3+ ions from aqueous solution observed for both powder and granular sorbents. The low price for crumbling metallurgical slag, environmental aspects of storage and high sorption capability enable recycling and use of this material as a sorbent with subsequent purification of large natural objects from Ce3+ ions. (C) 2020 Elsevier Ltd. All rights reserved.