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Updated: Jul 3, 2026

Quantification of Humic and Fulvic Acids in Humate Ores, DOC, Humified Materials and Humic Substance-Containing Commercial Products
Published on: March 18, 2022
[Adsorption of humic acid onto aminated HMS]
Qi Tao1, Zhao-Yi Xu, Shou-Rong Zheng
1State Key Laboratory of Pollution Control and Resource Reuse, School of Environment, Nanjing University, Nanjing 210093, China. breeze3509@sina.com
Abstract:
The adsorption of humic acid onto hexagonal mesoporous silica(HMS) and surface aminated HMS was investigated. The simulation results using Freundlich model indicated that the surface amination of HMS led to an increase of adsorption constant from 0.56 to 105, reflecting markedly enhanced adsorption of humic acid upon surface amination. In addition, humic acid adsorption under acidic conditions was favored. Adsorbed humic acid molecules were found to be located in the mesopores of aminated HMS and the mesopores with relatively larger pore diameters were preferentially occupied. The kinetics of humic acid adsorption onto the aminated HMS could be well described by second order kinetics and the adsorption rate was mainly dominated by intrapore diffusion process.
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