Dynamic adsorption of Cd²⁺ from aqueous solution using biochar of pine-fruit residue

ABSTRACT

The present investigation describes the applicability of biochar of pine-fruit residue (PFR) as a novel adsorbent for Cd²⁺ adsorption in the packed-bed system. Biochar was characterised for surface properties using BET surface area, Boehm titration, FT-IR and a scanning electron microscopy (SEM). Experiments were performed to investigate the influence of operational parameters such as bed height (Z = 5, 10 and 20 cm), metal-ion concentration (C_o= 25, 50 and 100 mg · L⁻¹) and flow-rate (Q = 2, 5 and 10 mL · min⁻¹) on Cd²⁺ uptake capacity (q_exp). Maximum q_exp of 17.93 mg · g⁻¹ corresponding to 51.90% of Cd²⁺ removal was obtained for Z = 5 cm, C_o= 50 mg · L⁻¹, Q = 2 mL · min⁻¹ at pH 6.9 and 303 K. Established Thomas and Yoon-Nelson models were used to analyse experimental data and the model parameters were evaluated. The comparative study of error functions of Cd²⁺ adsorption capacity predicted by model showed that Thomas model is the best fit. The sorption efficiency of regenerated biochar in successive sorption–desorption cycles was 38.96% at the end of the third cycle.

KEYWORDS:

• Biochar
• adsorption
• cadmium
• column study
• modelling

Disclosure statement

No potential conflict of interest was reported by the authors.

ORCID

Pawan D. Meshram http://orcid.org/0000-0002-3146-9843