2025

Marković, Marina
Gorgievski, Milan 
Marković, Miljan 
Grekulović, Vesna 
Štrbac, Nada 
Zdravković, Milica 
Božinović, Kristina 

University of Zenica, Faculty of Metallurgy and Technology

Journal of Sustainable Technologies and Materials

5

8

1

4

English

The changes in pH and conductivity during the rinsing of the pumpkin peel, and the biosorption of Cu2+ ions, were the subject of this work. The obtained data showed that the pH value of the solutions increased during the rinsing of the biosorbent, as a result of the transfer of H+ ions from the aqueous phase into the structure of the pumpkin peel. An increase in the conductivity value was observed in the initial period of rinsing the pumpkin peel, followed by a decrease. The increase in conductivity in the initial phase contributed to the self-leaching of the alkali and alkaline earth metal ions from the structure of the pumpkin peel, which were transferred into the aqueous phase. The further decrease in conductivity is a result of the dilution of the aqueous phase. The pH value decreased during the biosorption of Cu2+ ions, as hydrogen ions were transferred from the pumpkin peel structure into the solution, and then exchanged with Cu2+ ions. The conductivity value increased during the biosorption process, with a rapid increase in the initial period of 5 minutes, due to the transfer of alkali and alkaline earth metal ions into the solution.

biosorption, pumpkin peel, pH, conductivity

DOI

10.57131/jstm.2025.8.1

ISSN

2744-2659
2744-2640

URI

https://repozitorijum.tfbor.bg.ac.rs/handle/...