The effect of mineralogy of calcined shales on the alkali activation and geopolymerization reactions: A case study from Abu-Tartur plateau, Western Desert, Egypt

Enhancement of Uranium Recycling from Tailings Caused by the Microwave Irradiation-Induced Composite Oxidation of the Fe–Mn Binary System

“…The peak at 779 cm –1 was directly attributed to the existence of (UO 2 ) 2+ stretching vibration in the mineral constitution, ,, which was further proved by the XRD pattern of the raw uranium tailing sample (Figure S2, SI). The bands at 470, 1304, 1626, 3622, and 3697 cm –1 had barely changed after different leaching experiments, which were directly assigned to the gangue or inert constituents contained in the mineral, such as Si–O–Si bending vibration and Si–O and P–O symmetric and asymmetric stretching. − The band at 1083 cm –1 in the spectrum of the mixture specimen was ascribed to SO 2 asymmetric and symmetric stretching, which verified the addition of ferric sulfate to the tailing particles. − After MW irradiation, the raw band at 537 cm –1 was shifted left to the band at 516 cm –1 , which reflected the transformation of crystalline silicate to the partial amorphous phase. − The emergence of the peak at 516 cm –1 for the specimen obtained from the sulfuric leaching revealed the substitution of Al 3+ in the octahedral lattice by H + ions. The result demonstrated the dissolution of some minerals from the specimen by the sulfuric solution.…”

“… 69 − 71 The band at 1083 cm –1 in the spectrum of the mixture specimen was ascribed to SO 2 asymmetric and symmetric stretching, which verified the addition of ferric sulfate to the tailing particles. 72 − 74 After MW irradiation, the raw band at 537 cm –1 was shifted left to the band at 516 cm –1 , which reflected the transformation of crystalline silicate to the partial amorphous phase. 70 − 72 The emergence of the peak at 516 cm –1 for the specimen obtained from the sulfuric leaching revealed the substitution of Al 3+ in the octahedral lattice by H + ions.…”