0
Article ? AI-assigned paper type based on the abstract. Classification may not be perfect — flag errors using the feedback button. Tier 2 ? Original research — experimental, observational, or case-control study. Direct primary evidence. Remediation Sign in to save

Effect of Microplastics on Cu2+ Adsorption by β-cyclodextrin Modified Biochar

Water Air & Soil Pollution 2025
Hua Tong, Xiangyi Gong, Fengying Wu, Hao Li, Dajun Ren

Summary

This study found that both polypropylene and polystyrene microplastics significantly inhibited copper ion adsorption by a novel beta-cyclodextrin modified biochar in water remediation tests, reducing maximum copper uptake by up to 24% through surface blocking and pore occlusion. The results reveal that co-occurring microplastics can undermine the effectiveness of engineered adsorbents for heavy metal removal, complicating real-world water treatment in contaminated environments where multiple pollutants coexist.

Polymers

The pervasive co-existence of microplastics with other pollutants complicates the efficacy of adsorbents in water remediation. This study, therefore, investigates the under-explored impact of polypropylene (PP) and polystyrene (PS) microplastics on the adsorption of Cu2+ by a novel β-cyclodextrin modified biochar (β-BC). Results revealed a significant inhibition of Cu2+ removal in the presence of both microplastics, with the Langmuir maximum adsorption capacity decreasing from 38.12 mg/g for β-BC alone to 33.03 mg/g with PP and 29.07 mg/g with PS. The stronger inhibition by PS is attributed to surface site coverage via π-π stacking interactions, whereas PP's interference stems primarily from physical pore blockage. Furthermore, the inhibitory effect was pH-dependent, while high salinity or humic acid concentrations unexpectedly promoted the overall Cu2+ uptake, highlighting the complex role of environmental factors. This work underscores the critical need to consider microplastic interference when evaluating adsorbents for real-world environmental applications.

Share this paper