Sustainable Remedy Waste to Generate SiO2 Functionalized on Graphene Oxide for Removal of U(VI) Ions

Abstract

The Hummer process is applied to generate graphene oxide from carbon stocks’ discharged Zn-C batteries waste. SiO2 is produced from rice husks through the wet process. Subsequently, SiO2 reacted with graphene oxide to form silica/graphene oxide (SiO2/GO) as a sorbent material. XRD, BET, SEM, EDX, and FTIR were employed to characterize SiO2/GO. Factors affecting U(VI) sorption on SiO2/GO, including pH, sorption time, a dosage of SiO2/GO, U(VI) ions’ concentration, and temperature, were considered. The experimental data consequences indicated that the uptake capacity of SiO2/GO towards U(VI) is 145.0 mg/g at a pH value of 4.0. The kinetic calculations match the pseudo second-order model quite well. Moreover, the sorption isotherm is consistent with the Langmuir model. The sorption procedures occur spontaneously and randomly, as well as exothermically. Moreover, SiO2/GO has essentially regenerated with a 0.8 M H2SO4 and 1:50 S:L phase ratio after 60 min of agitation time. Lastly, the sorption and elution were employed in seven cycles to check the persistent usage of SiO2/GO.

Characteristic Aspects of Uranium(VI) Adsorption Utilizing Nano-Silica/Chitosan from Wastewater Solution

“…Hydrothermal synthesis yielded mesoporous, spherical nano-silica [ 34 , 35 ]. The suspension of cetyltrimethylammonium bromide (CTAB) in deionized water, with the addition of 1 M NaOH (10 mg/mL) and an equal volume of water, was carried out at 80 °C.…”

Recovery of W(VI) from Wolframite Ore Using New Synthetic Schiff Base Derivative

“…The thermodynamic parameters controlling the sorption system (Δ G °, Δ H °, and Δ S °) were mathematically determined from the Van ’t Hoff equations as follows [ 51 , 52 ]: where T is a symbol of the temperature of the system ( K ), and R stands for the gas constant (8.314 J mol −1 K −1 ). Both ∆ H ° and ∆ S ° can be calculated from the slope and the intercept of log K d against the 1/ T plot, as illustrated in Figure 14 .…”

Selective Recovery of Cadmium, Cobalt, and Nickel from Spent Ni–Cd Batteries Using Adogen® 464 and Mesoporous Silica Derivatives

“…The model is usually described by Equation (6): where C e (mg·L −1 ) is the equilibrium concentration, q e (mg·g −1 ) is the equilibrating uptake of adsorbed Co 2+ , q max (mg·g −1 ) is maximal sorption capability, and b (L·mg −1 ) is equilibrating adsorbance constant. Freundlich modeling is presumed such that adsorption performance is carried out with variable binding energies in scenarios with a heterogeneous surface ( Figure 7 d) [ 68 , 69 , 70 , 71 , 72 , 73 ]. The Freundlich modeling is expressed as Equation (7): where k f (mg·g −1 ) is the uptake of the Freundlich continuum and n is the sorption intensity parameter.…”