Low-cost and efficient adsorbent derived from pyrolysis of Jatropha curcas seeds for the removal of Cu²⁺ from aqueous solutions

ABSTRACT

Biochar, is a low-cost material that can be used as an alternative adsorbent for the removal of heavy metals. In this study, a low-cost and efficient adsorbent synthesised from Jatropha curcas seeds was used for the uptake of Cu²⁺ from aqueous solutions. The as-prepared adsorbent was characterised by scanning electron microscopy and Brunauer–Emmett–Teller analysis post calcination at 500 °C, its BET surface area and total pore volume were 39.62 m² g⁻¹ and 0.049 m³ g⁻¹, respectively. Subsequently, the effects of initial pH of the solution, contact time, and adsorbent material dosage on the adsorption of Cu²⁺ by the prepared adsorbent were investigated. The as-prepared adsorbent exhibited a high performance, with a maximum adsorption amount of 32.895 mg g⁻¹ for Cu²⁺ at pH 5.0 and 25 °C, owing to the presence of −OH, C=O, C–O, Si-O-Si, and O-Si-O on its surface. The predominant Cu²⁺ adsorption mechanism was assumed to be ion exchange. Notably, the Cu²⁺ adsorption could attain equilibrium within 90 min. In addition, the fact that the Langmuir model was a better fit than the Freundlich model for the isotherm data of Cu²⁺ adsorption by the as-prepared adsorbent suggested that the adsorption of Cu²⁺ was a monolayer adsorption process.

KEYWORDS:

• Biochar
• removal of Cu²⁺
• Jatropha curcas seeds
• adsorption kinetics

Disclosure statement

No potential conflict of interest was reported by the authors.

Notes on contributors

Weiyuan Zuo is a Master at Key Laboratory of Regional Ecological Environment Analysis and Pollution Control of West Guangxi, College of Chemistry and Environmental Engineering, Baise University.

Bingfang Shi is a Professor at Key Laboratory of Regional Ecological Environment Analysis and Pollution Control of West Guangxi, College of Chemistry and Environmental Engineering, Baise University.

Shengyu Chen is a Master at Key Laboratory of Regional Ecological Environment Analysis and Pollution Control of West Guangxi, College of Chemistry and Environmental Engineering, Baise University.

Xiaoli Zhou is a Master at Key Laboratory of Regional Ecological Environment Analysis and Pollution Control of West Guangxi, College of Chemistry and Environmental Engineering, Baise University.

Yan Duan is a Doctor at Key Laboratory of Regional Ecological Environment Analysis and Pollution Control of West Guangxi, College of Chemistry and Environmental Engineering, Baise University.

Anping Liao is a Professor at Key laboratory of chemical and biological transformation process of Guangxi Higher Education Institutes, School of Chemistry and Chemical Engineering of Guangxi University for Nationalities.

Additional information

Funding

This work was supported by the National Natural Science Foundations of China [grant number 21665001; 41163007]; the Natural Science Foundations of Guangxi Province [grant number 2012GXNSFAA053036] and 2017 Young teacher basic ability enhancement project of Colleges and universities in Guang xi [grant number 2017KY0728].