Copyrolysis of microalga Chlorella sp. and alkali lignin with potassium carbonate impregnation for synergistic Bisphenol A plasticizer adsorption

Composite functional materials offer promising opportunities for the development of tailored adsorbents with enhanced bioremediation potential towards toxic, carcinogenic endocrine disrupters such as Bisphenol A (BPA). Copyrolysis of microalga Chlorella sp. (CH) alkali lignin (L) with K₂CO₃ impregnation yielded a carbon-based composite (CHL-AC) with a micro–mesoporous structure of 0.643 cm³/g, surface area of 1414 m²/g, and BPA adsorption capacity of Q_max 316.858 mg/g. Enhanced BPA removal efficiency indicated a positive synergistic effect upon a combination of L and CH, resulting in a 73.24 % removal efficiency compared with the individual carbon components of 52.33 % for L-AC and 67.35 % for CH-AC. The kinetics and equilibrium results were described well by the pseudo second-order kinetic model and Freundlich isotherm, respectively. This paper elucidates the blending of microalgae and lignin into high-value carbon composite material, CHL-AC, with immense potential for the treatment of BPA-contaminated waters to contribute to Goal 6 (clean water and sanitation).