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Updated: Nov 12, 2025
09:39
Physical, Chemical and Biological Characterization of Six Biochars Produced for the Remediation of Contaminated Sites
Published on: November 28, 2014
35.4K
Soil colloids affect the aggregation and stability of biochar colloids.
Xiangyang Gui1, Bingqing Song2, Ming Chen3
1China-UK Low Carbon College, Shanghai Jiao Tong University, Shanghai 201306, China.
The Science of the Total Environment
|March 19, 2021
Summary
Soil colloids like kaolin, goethite, and humic acid significantly impact biochar colloid stability and aggregation. Understanding these interactions is crucial for predicting biochar
Area of Science:
- Environmental Science
- Soil Science
- Colloid Chemistry
Background:
- Biochar colloid stability is vital for soil contaminant and nutrient transport.
- Soil components influence the behavior of biochar colloids in terrestrial ecosystems.
Purpose of the Study:
- To investigate the effects of kaolin, goethite, and humic acid on biochar colloid aggregation kinetics.
- To determine how different biochar types (dairy manure, sewage sludge, wheat straw) interact with soil colloids.
Main Methods:
- Assessed aggregation kinetics of biochar colloids (dairy manure, sewage sludge, wheat straw).
- Examined the influence of kaolin, goethite, and humic acid on biochar colloid stability.
- Measured critical coagulation concentration (CCC) to quantify stability.
Main Results:
- Wheat straw biochar exhibited the highest stability (CCC 624 mM) due to abundant functional groups.
- Kaolin enhanced dairy manure and sewage sludge biochar stability but aggregated wheat straw biochar.
- Goethite induced aggregation in sewage sludge and wheat straw biochars, but inhibited dairy manure biochar aggregation.
- Humic acid consistently increased the stability of all biochar colloids, raising CCC to 827-1012 mM.
Conclusions:
- Soil kaolin, goethite, and humic acid colloids significantly alter biochar colloid stability and aggregation.
- These interactions are critical for understanding the environmental fate and behavior of biochar in soils.
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