4.7 Article

The impact of recycling alum-humic-floc (AHF) on the removal of natural organic materials (NOM): Behavior of coagulation and adsorption

Journal

CHEMICAL ENGINEERING JOURNAL
Volume 284, Issue -, Pages 1049-1057

Publisher

ELSEVIER SCIENCE SA
DOI: 10.1016/j.cej.2015.09.069

Keywords

Humic acid (HA); Alum-humic-floc (AHF); Adsorption capacity; Coagulation kinetic; Hydrogen bond

Funding

  1. Funds for Major Science and Technology Program for Water Pollution Control and Treatment [2012ZX07408001, 2014ZX07405002]
  2. State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology [ES201511]

Ask authors/readers for more resources

Recycling alum flocs may promote the removal of NOM during the coagulation process. The performance of alum-humic-floc (AHF), poly aluminum chloride (PACl) and AHF and PACl mixtures (AHF+PACl) in the removal of humic acid (HA) were comparatively evaluated in regards to their coagulation behaviors and floc structure characteristics. Jar tests were conducted at neutral pH and in a dosage range from 6.11 to 26.49 mg Al/L. The dual coagulant, AHF with additional PACl, could significantly improve the removal efficiency of organic matter and residual turbidity, which probably depended on the physical adsorption and the charge neutralization mechanism. The experimental data using AHF fit with BET and Freundlich models, which indicated that the adsorption of HA onto AHF was a multilayer adsorption. Floc characterization was also performed to investigate the relationship between floc structure and organic matter removal. The highest removal efficiency of organic matter and residual turbidity occurred when using the combination of AHF with additional PACl as the coagulant, which suggested that fractal dimension of the flocs was the most significant factor in determining the removal of pollutants from the water solution. HA was released again into solution during floc breakage. The combination of AHF and PACl demonstrated a lower release of organic matter after breakage and the stronger dissolved organic carbon (DOC) removal capacity during re-growth process. The functional group on the AHF was the main factor in site-specific hydrogen bonding, which is the main mechanism for removal of HA. (C) 2015 Elsevier B.V. All rights reserved.

Authors

I am an author on this paper
Click your name to claim this paper and add it to your profile.

Reviews

Primary Rating

4.7
Not enough ratings

Secondary Ratings

Novelty
-
Significance
-
Scientific rigor
-
Rate this paper

Recommended

No Data Available
No Data Available