Isotherm and thermodynamic studies of Zn (II) adsorption on lignite and coconut shell-based activated carbon fiber

The behaviors and characteristics of a mesoporous activated carbon prepared from Tamarix hispida for Zn(II) adsorption from wastewater

“…The increase in adsorption efficiency of Zn(II) by the ACTH with an increase in the temperature may be due to the development of new adsorption sites on the surface of ACTH or to the increased kinetic energy of the Zn(II) ions [27]. This result is consistent with previous literature [7,[27][28][29] however, the magnitude of temperature-dependence was different, which may be due to differences in nature of the adsorbent and test conditions.…”

Removal of zinc and lead from aqueous solution by nanostructured cedar leaf ash as biosorbent

“…FTIR spectrum after adsorption shows that wave numbers and the intensity of some peaks are shifted or substantially lower than those before adsorption. An absorption band around 3375.64 cm − 1 corresponding to O-H or N-H groups is shifted to 3326.37 cm −1 after adsorption of Pb 2+ and 3232.51 after adsorption of Zn 2+ , which may be ascribed to the complexion of OH and amide groups with metals ions [37][38][39][40]. The peaks at 1615.9 cm − 1 , 1631 cm − 1 and 1649.89 cm − 1 may be attributed to C_O stretching vibration [40][41][42][43][44].…”

Removal of cadmium and lead from aqueous solutions by magnetic acid-treated activated carbon nanocomposite

“…Positive values of ΔH˚indicated that the adsorption processes for both Cd 2+ and Pb 2+ were endothermic [104]. Also, positive values of ΔS˚showed the affinity of the metal ions and increasing randomness at solidsolution interface during the adsorption process [105]. Negative values of ΔG˚indicated spontaneous adsorption in which the degree of spontaneity increased with the increase in the temperature [106].…”