In this paper, green and facile synthesis of sulfur-and nitrogen-codoped carbon nanospheres (CNs) was prepared from the extract of Hibiscus sabdariffa L by a direct hydrothermal method. Finally, sulfur-carbon nanospheres (CNs) were used as the adsorbent to remove Pb +2 ions from aqueous solutions because of the high surface area of S-CNs from CNs and N-CNs. e synthesized nanospheres were examined by Fourier transform infrared (FTIR) spectroscopy, X-ray diffraction (XRD), field emission scanning electron microscopy, transmission electron microscopy (TEM), and nitrogen adsorption-desorption isotherms. e results show spherical shapes have a particle size of up to 65 nm with a high surface area capable of absorbing lead ions efficiently. Additionally, the factors affecting the process of adsorption that include equilibrium time, temperature, pH solution, ionic intensity, and adsorbent dose were studied. e equilibrium removal efficiency was studied employing Langmuir, Freundlich, and Temkin isotherm forms. e kinetic data were analyzed with two different kinetic models, and both apply to the adsorption process depending on the values of correlation coefficients. e thermodynamic parameters including Gibbs free energy (ΔG°), standard enthalpy change (ΔH°), and standard entropy change (ΔS°) were calculated for the adsorption process.
SYNOPSISHydroxy-terminated polybutadiene (HTPB ) liquid prepolymers (I-IX ), with closely similar OH values, M,,, viscosity, and microstructure, were synthesized by Hz02-initiated freeradical polymerization of butadiene in an isopropanol-water solvent system. However, binders obtained by curing HTPB polymers showed wide variations in their sol content, cross-link density, and mechanical properties. These variations were attributed to the differences in functionality-type distribution (FTD ) and molecular weight distribution
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.