Comparative study of natural and modified Abies bornmulleriana cones in the removal of copper (II) ions

Abies bornmulleriana cones and their modified forms were used to uptake the Cu (II) ions and compare biosorption efficiency and biosorbent capacity. The effect of various experimental conditions on the uptake of the Cu (II) ions was researched. Additionally, Cu (II) ion removal efficiency and capacity were investigated in the presence of Pb (II) ions. Besides, the Cu (II) ions' removal mechanism was illustrated in terms of FTIR results. Electrophoretic mobilities of the normal and modified cones were determined to get information about the biosorption. The Brunauer, Emmett, and Teller surface area and pore volume per gram of cones before and after biosorption were identified as (5.05 m(2) and 0.0018 cm(3)) and (0.97 m(2) and 0.00032 cm(3)), respectively. The average pore width of the biosorbent before and after the biosorption was calculated as 9.34 and 13.04 A, respectively. The pseudo-second-order kinetic gave the best fit to the biosorption data (R-2 0.99, 0.99). The biosorption data for the normal and modified biosorbent fitted well to Dubinin-Radushkevitch (D-R) isotherm due to the high R-2 values (0.99, 0.98), and the maximum biosorption capacities were determined as 16.58 and 25.35 mg g(-1), respectively. Delta H degrees, Delta S degrees, and Delta G degrees parameters were estimated from the linear plot of lnKd vs. (1/T). The normal and modified biosorbent regeneration with 0.5 N HNO3 showed that the biosorption and desorption processes were reversible.

Automated summary

This study investigated the uptake of Cu(II) ions using Abies bornmulleriana cones and their modified forms, as well as the effects of various experimental conditions on the uptake. The results showed that the biosorption efficiency and capacity of Cu(II) ions varied under different conditions. Additionally, the removal mechanism of Cu(II) ions was illustrated based on FTIR results, and the biosorption data fit well to the pseudo-second-order kinetic and Dubinin-Radushkevitch isotherm models.