Preparation and characterization of a novel functionalized agricultural waste-based adsorbent for Cu2+ removal: Evaluation of adsorption performance using response surface methodology


CERRAHOĞLU KAÇAKGİL E. , Cetintas S.

SUSTAINABLE CHEMISTRY AND PHARMACY, vol.22, 2021 (Journal Indexed in SCI) identifier identifier

  • Publication Type: Article / Article
  • Volume: 22
  • Publication Date: 2021
  • Doi Number: 10.1016/j.scp.2021.100468
  • Title of Journal : SUSTAINABLE CHEMISTRY AND PHARMACY
  • Keywords: Agricultural waste, Cu2+ adsorption, Modified adsorbent, Optimization, HEAVY-METALS CU2+, IRON-OXIDE, ACTIVATED CARBON, EFFICIENT REMOVAL, ION-EXCHANGE, COPPER IONS, DYE REMOVAL, DATE PALM, ISOTHERM, EQUILIBRIUM

Abstract

In this study, it was aimed to the improvement of adsorption capability with a novel modification method based on increasing surface activity of flaxseed waste (FW), an agricultural waste product, and the investigation of its usability as an effective adsorbent for Cu2+ removal. The modification method involves functionalization of FW with iron by adding FeCl3 to medium in presence of N, N-Dimethyl-formamide, poly (N-vinyl-pyrrolidone), and hexamethylenetetramine. The effect of parameters was investigated by conventional univariate analysis. In addition, Response Surface Methodology (RSM) based on multivariate analysis was used to improve the performance of Cu2+ adsorption onto iron-modified flaxseed waste (M - FW). Cu2+ removal efficiency was achieved as 91.46% +/- 2.34 (N = 2) at an equilibrium time of only 15 min under determined optimum conditions as Co: 75 ppm, pH: 4.7, and m: 0.23 g. RSM was successfully applied for the prediction of adsorption. Adsorption nature was as a single-layer adsorption with a maximum adsorption capacity (Q(max)) of 7.64 mg/g. The adsorption mechanism, determined to be chemically controlled, an exothermic and non-spontaneous process. Furthermore, pH-dependent adsorption showed that electrostatic interactions between M - FW and Cu2+ ions play an important role in adsorption mechanism. The results of characterization studies showed that a large surface area was provided with increased porosity of structure and desired changes occurred in target functional structures with modification. Moreover, modification and reusability of M - FW were evaluated in terms of overall sustainability and waste management. The results indicated that M - FW has potential for usability to remove heavy metals like Cu2+ in environmental remediation applications.