Waste non-burn-free brick derived sulfhydryl functioned magnetic zeolites and their efficient removal of uranium(VI) ions

Abstract Utilising the general waste such as non-burning brick as raw materials to prepare low-cost zeolite is in line with the green chemical industry and can achieve the purpose of treating waste with waste. Here we use the abandoned non-burning brick powder as raw material, the sulfhydryl functionalized magnetic zeolite composites (MZ-SH) were prepared by combining a series of methods such as hydrothermal synthesis, high temperature melting magnetization, and grafting technology. The samples were characterized by SEM, EDS, XRD, XPS, and FT-IR. The adsorption behavior of MZ-SH on uranyl ions was systematically studied. The results show that the equilibrium adsorption capacity of MZ-SH to uranium(VI) ions was 1285.86 mg/g under the optimal adsorption conditions with t of 270 mins, T at 35 ℃, C0 being 35 mg/L, pH at 6.0, and m by 0.025 g/L. Its adsorption isotherm complies with the Langmuir adsorption model, while the adsorption kinetics conforms to the quasi-second-order adsorption kinetic model. The adsorption type is mainly chemical adsorption with type of monolayer distribution on the surface. Adsorption thermodynamics shows that the adsorption process was spontaneous at 25-45 ℃. FT-IR and XPS analysis showed that sulfhydryl, -OH, Al-O and Si-O played an important role in the adsorption process of uranium (VI) ions by MZ-SH. It indicates that the uranium(VI) ions prefer binding with -OH and sulfhydryl groups and there is also showing ion exchange between uranium(VI) ions and Al-O and Si-O groups.