Lignocellulosic fraction of the pericarps of the acorns of Quercus suber and Quercus ilex : isolation, characterization, and biosorption studies in the removal of copper from aqueous solutions

Abstract Pericarps of Algerian Quercus ilex ( Q. ilex ) and Quercus suber ( Q. suber ) were used as copper adsorbents in artificially contaminated solutions. Exposing accessible lignocellulosic binding sites enhanced adsorption. The lignocellulosic fractions of Q. suber and Q. ilex (36.47±9.1 and 47.66±9.3, respectively) were characterized by FTIR before and after adsorption. The aim was to identify the functional groups adsorbing Cu(II). SEM/EDX determined lignocellulose surface morphology and composition. The amount of adsorbent-bound Cu(II) increased with initial [Cu(II)]. Cu(II) adsorption range was 23.59–48.06 mg.g −1 for Q. Suber and 22.56–38.19 mg.g −1 for Q. ilex when [Cu(II)] was 100–500 mg.L −1 . Adsorption isotherms and Langmuir and Freundlich models of the Q. suber and Q. ilex lignocellulosic fractions indicated natural Cu(II)adsorption capacities (Q max ) of 53.76 mg.g −1 and 36.06 mg.g −1 and KF of 5.9 mg.g −1 and 7.43 mg.g −1 , respectively.