Insoluble humic substances

3.4× higher Cu adsorption

Rapidly adsorbs and long-term stabilizes Cu in sediments via complexation and bridging, promoting transformation to stable fractions and inhibiting release.

Huang, Weifang · Luming, Dou · Chen, Meng · Yi-yi, Chen · Li, Longguo · Li, Jun · Li, Naiwen · Liu, Chao · Lai, Bo

Water Research 2026

Specifications

Cu adsorption capacity

{'zh': '16.129', 'en': '16.129'} mg/g

Desorption rate

{'zh': '3.25', 'en': '3.25'} %

Overlying water Cu concentration

{'zh': '0.022-0.043', 'en': '0.022-0.043'} mg/L

Proportion of oxidizable and residual fractions

{'zh': '81.49', 'en': '81.49'} %

Advantages

Higher adsorption

Increasing IHS content enhanced Cu adsorption 3.4-fold via functional group chelation and ternary bridging complexes.

Less release

Desorption decreased from 8.74% to 3.25%, indicating that adsorbed Cu is less prone to release.

Long-term stabilization

Promotes transformation of Cu from exchangeable to oxidizable and residual fractions, reaching 81.49% stable fractions with 20% IHS.

Reduces water contamination

Overlying water Cu concentrations were reduced to 0.022-0.043 mg/L, up to 7.3-fold lower than control.

Applications

• Agricultural heavy metal remediation：Remediate Cu-contaminated farmland soils, reducing crop uptake risk.
• Water environment remediation：Reduce Cu concentration in overlying water, improving water quality.
• In-situ sediment stabilization：In-situ stabilize Cu in sediments, preventing re-release.
• Soil amendment：Serve as soil amendment to enhance heavy metal immobilization.