Limonene‐derived hollow polymer particles: Preparation and application for the removal of dyes and heavy metal ions

Abstract Herein, a unique kind of sustainable limonene‐derived hollow polymeric particles (LHPPs) were synthesized based on a widely available biomass monocyclic terpene limonene, which could act as efficient adsorption material to remove cationic dyes (methylene blue, MB) and heavy metal ions (Ni 2+ ). Benefiting from the hollow structure/porous shell layer and abundant carboxylic groups, LHPPs exhibit outstanding sorption ability, quick sorption velocity, and excellent regeneration. The adsorption results of MB and Ni 2+ onto LHPPs were analyzed by utilizing two most common models, and the adsorption isotherms were better simulated by Langmuir equation, showing maximum sorption capacities of 909 and 75.8 mg/g. Furthermore, the sorption processes were better described with pseudo‐second order equation. Besides, the LHPPs exhibit a remarkable pH‐sensitive adsorption property because of the existence of carboxylic groups. When the pH value changed from 2 to 10, the sorption capacity for MB increased sharply from 226 to 829 mg/g, and the sorption capacity for Ni 2+ enhanced remarkably from 6 to 74.9 mg/g with pH value increased in the range of 2–6. Moreover, these biobased adsorbents show high reusability over five adsorption/desorption cycles, making LHPPs promising sustainable absorbents for practical application in water treatment.