Production of activated carbon from food wastes (chicken bones and rice waste) by microwave assisted ZnCl₂ activation: an optimized process for crystal violet dye removal

Abstract

A major worldwide challenge that presents significant economic, environmental, and social concerns is the rising generation of food waste. The current work used chicken bones (CB) and rice (R) food waste as alternate precursors for the production of activated carbon (CBRAC) by microwave radiation-assisted ZnCl₂ activation. The adsorption characteristics of CBRAC were investigated in depth by removing an organic dye (crystal violet, CV) from an aquatic environment. To establish ideal conditions from the significant adsorption factors (A: CBRAC dosage (0.02–0.12 g/100 mL); B: pH (4–10); and C: duration (30–420), a numerical desirability function of Box-Behnken design (BBD) was utilized. The highest CV decolorization by CBRAC was reported to be 90.06% when the following conditions were met: dose = 0.118 g/100 mL, pH = 9.0, and time = 408 min. Adsorption kinetics revealed that the pseudo-first order (PFO) model best matches the data, whereas the Langmuir model was characterized by equilibrium adsorption, where the adsorption capacity of CBRAC for CV dye was calculated to be 57.9 mg/g. CV adsorption is accomplished by several processes, including electrostatic forces, pore diffusion, π-π stacking, and H-bonding. This study demonstrates the use of CB and R as biomass precursors for the efficient creation of CBRAC and their use in wastewater treatment, resulting in a greener environment.

NOVELTY STATEMENT

The novelty of this research work relates to converting food wastes (mixture of chicken bones and rice waste) into activated carbon via microwave assisted ZnCl₂ activation. Moreover, the produced activated carbon was successfully applied as a potential adsorbent for removal of a toxic cationic dye; namely, crystal violet (CV) from aqueous environment.

Keywords:

• Activated carbon
• adsorption
• cationic dye
• food waste management
• microwave

Acknowledgments

The authors are thankful to the Faculty of Applied Sciences, Universiti Teknologi MARA (UiTM) Shah Alam, Malaysia for the research facilities. The author (Zeid A. AlOthman) would like to extend his appreciation to the Deputyship for Research & Innovation, Ministry of Education in Saudi Arabia for funding this research work through the project no. (IFKSUOR3–338–1).

Disclosure statement

No potential conflict of interest was reported by the author(s).