Effect of Ozonation and Hydrogen Peroxide Oxidation on the Structure of Humic Acids and their Removal

Abstract:

Using pyrolysis-GC-MS and HPLC techniques, a series of studies were conducted on the effect of pre-oxidation on the structure of natural humic acids (HA) by ozone and hydrogen peroxide (H₂O₂). Both ozone and H₂O₂ could more or less result in direct removal of organic matter, but the removal of UV₂₅₄ was much higher than that of TOC, implying that an important function of the oxidants is to change the structure of the organic molecules rather than to decompose them into inorganic matters. The result of pyrolysis-GC-MS analysis showed that in the process of oxidation, the organic functional groups on the HA molecules underwent a significant change in their structure, mostly from cyclic to chain hydrocarbons and/or from aromatics to aliphatics. This process was also accompanied by a decrease in the molecular weight of the HA. With an apparent change in the structure and molecular weight of the HA molecules after pre-oxidation, a great improvement was seen on the overall removal of TOC as coagulation or GAC adsorption was subsequently applied. Additionally, in the case of H₂O₂, a small dose of O₃ showed much better catalysing effect than Mn²⁺, Cu²⁺ or Fe²⁺ ions.

• Periodical: Advanced Materials Research (Volumes 610-613)
• Pages: 1256-1259
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.610-613.1256
• Online since: December 2012
• Authors: Peng Kang Jin, Xin Jin, Xiao Chang Wang, Fan Bai
• Keywords: Humic Acid (HA), Hydrogen Peroxide, Oxidation, Ozonation

References

[1] J. Lowe, Md.M. Hossain, Application of ultrafiltration membranes for removal of humic acid from drinking water. Desalination 218(1-3): 343-354 (2008)

DOI: 10.1016/j.desal.2007.02.030

[2] V Camel, A Bermond, The use of ozone and associated oxidation processes in drinking water treatment. Water Research 32(11): 3208-3222 (1998)

DOI: 10.1016/s0043-1354(98)00130-4

[3] S. Samios, T. Lekkas, A. Nikolaou, S.Golfnopoulos, Structural investigations of aquatic humicsubstances from different watersheds. Desalination 210(1-3): 125-137 (2005)

DOI: 10.1016/j.desal.2006.05.038

[4] Hyun-Chul Kim, Myong-Jin Yu, Characterization of aquatic humic substances to DBPs formation in advanced treatment processes for conventionally treated water. Journal of Hazadous Materials 143(1-2):486-493 (2007)

DOI: 10.1016/j.jhazmat.2006.09.063

[5] Tambo N, Kamei T. Treatability evaluation of general organic matter: Matrix conception and its application for a regional water and waste water system. Water Research, 12: 931-950 (1978)

DOI: 10.1016/0043-1354(78)90077-5