Separation of Ni2+ and Co2+ Using Sorbitol–Stearic Acid-Derived Bio-Based Solvent: A Sustainable Solvent Extraction Approach

Bekir Özkan

doi:10.18596/jotcsa.1734826

Separation of Ni2+ and Co2+ Using Sorbitol–Stearic Acid-Derived Bio-Based Solvent: A Sustainable Solvent Extraction Approach

Abstract

The separation of Ni²⁺ and Co²⁺ is challenging due to their similar physicochemical properties. In industrial processes, solvent extraction is widely used for their refinement; however, the excessive use of petroleum-derived solvents poses significant environmental concerns. To address this, a greener approach was explored in this study by utilizing a bio-based solvent synthesized from sorbitol and stearic acid. The resulting solvent, SSA2, was prepared via Fischer esterification and employed as the organic phase in solvent extraction experiments. After 5 hours of reaction, the acid value (AV) of SSA2 decreased roughly 87%, indicated ester bond formation and the reduction of carboxylic acid groups, confirming successful synthesis. FTIR analysis confirmed the presence of ester bonds in SSA2, which are absent in the starting materials, sorbitol and stearic acid. The separation performance of SSA2 for Ni²⁺ and Co²⁺ was assessed by measuring the distribution coefficient (KD) and separation factor (SF) values as functions of contact time and aqueous phase pH. SSA2 demonstrated higher selectivity towards Co²⁺, achieving a maximum SFCo2+/Ni2+ of 6.20 at pH 5. The highest KD values recorded were 75.6 and 12.2 for Co²⁺ and Ni²⁺ respectively.

Keywords

Supporting Institution

TUBİTAK

Project Number

TÜBİTAK 123C318

Ethical Statement

The authors declare no competing financial interests.

Thanks

I would like to thank TÜBİTAK for their financial support on this research with Project Number 123C318

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Details

Primary Language

English

Subjects

Separation Science, Chemical Engineering (Other)

Journal Section

Research Article

Authors

Bekir Özkan ^*
0000-0003-4307-5806
Türkiye

Publication Date

December 1, 2025

Submission Date

July 5, 2025

Acceptance Date

October 28, 2025

Published in Issue

Year 2025 Volume: 12 Number: 4

DOI

https://doi.org/10.18596/jotcsa.1734826

IZ

https://izlik.org/JA46BN68UU

Cite

RIS / Bibtex

APA

Özkan, B. (2025). Separation of Ni2+ and Co2+ Using Sorbitol–Stearic Acid-Derived Bio-Based Solvent: A Sustainable Solvent Extraction Approach. Journal of the Turkish Chemical Society Section A: Chemistry, 12(4), 241-248. https://doi.org/10.18596/jotcsa.1734826

AMA

1.Özkan B. Separation of Ni2+ and Co2+ Using Sorbitol–Stearic Acid-Derived Bio-Based Solvent: A Sustainable Solvent Extraction Approach. JOTCSA. 2025;12(4):241-248. doi:10.18596/jotcsa.1734826

Chicago

Özkan, Bekir. 2025. “Separation of Ni2+ and Co2+ Using Sorbitol–Stearic Acid-Derived Bio-Based Solvent: A Sustainable Solvent Extraction Approach”. Journal of the Turkish Chemical Society Section A: Chemistry 12 (4): 241-48. https://doi.org/10.18596/jotcsa.1734826.

EndNote

Özkan B (December 1, 2025) Separation of Ni2+ and Co2+ Using Sorbitol–Stearic Acid-Derived Bio-Based Solvent: A Sustainable Solvent Extraction Approach. Journal of the Turkish Chemical Society Section A: Chemistry 12 4 241–248.

IEEE

[1]B. Özkan, “Separation of Ni2+ and Co2+ Using Sorbitol–Stearic Acid-Derived Bio-Based Solvent: A Sustainable Solvent Extraction Approach”, JOTCSA, vol. 12, no. 4, pp. 241–248, Dec. 2025, doi: 10.18596/jotcsa.1734826.

ISNAD

Özkan, Bekir. “Separation of Ni2+ and Co2+ Using Sorbitol–Stearic Acid-Derived Bio-Based Solvent: A Sustainable Solvent Extraction Approach”. Journal of the Turkish Chemical Society Section A: Chemistry 12/4 (December 1, 2025): 241-248. https://doi.org/10.18596/jotcsa.1734826.

JAMA

1.Özkan B. Separation of Ni2+ and Co2+ Using Sorbitol–Stearic Acid-Derived Bio-Based Solvent: A Sustainable Solvent Extraction Approach. JOTCSA. 2025;12:241–248.

MLA

Özkan, Bekir. “Separation of Ni2+ and Co2+ Using Sorbitol–Stearic Acid-Derived Bio-Based Solvent: A Sustainable Solvent Extraction Approach”. Journal of the Turkish Chemical Society Section A: Chemistry, vol. 12, no. 4, Dec. 2025, pp. 241-8, doi:10.18596/jotcsa.1734826.

Vancouver

1.Bekir Özkan. Separation of Ni2+ and Co2+ Using Sorbitol–Stearic Acid-Derived Bio-Based Solvent: A Sustainable Solvent Extraction Approach. JOTCSA. 2025 Dec. 1;12(4):241-8. doi:10.18596/jotcsa.1734826