Degradation of biotansformation products of nonylphenol ethoxylates by ozonation and UV/TiO2 treatment

Abstract

The degradation kinetics of biotransformation products of nonylphenol polyethoxylates (NPEOs), nonylphenol (NP), nonylphenol monoethoxylate (NP1EO) and nonylphenoxy carboxylic acid (NP1EC), by ozonation and UV/TiO2 (ultraviolet photocatalytic degradation in the presence of titanium dioxide suspension as a catalyst) were investigated using lab-scale reactors. The degradation rate of NP by UV/TiO2 was the highest among the tested NPEOs metabolites, while NP1EC showed the lowest degradation rate. In contrast, ozonation was especially effective for the breakdown of NP1EC. NP could be also degrade efficiently by ozonation, however, it was much less effective for NP1EO decomposition. Degradation of NP by both chemical oxidation processes followed first-order kinetics. The degradation curves of NP1EO and NP1EC could be approximately described by first-order kinetics also, although the degradation of NP1EC by ozonation seemed to follow a second-order kinetic.

Synthetic endocrine disruptors in the environment and water remediation by advanced oxidation processes

“…They proposed that the reaction was initiated by dOH attack on the benzene ring resulting in the production of low molecular weight intermediates and CO 2 . Ike et al (2002) compared heterogeneous and homogeneous degradation of NP by photocatalysis in TiO 2 suspension and ozonation, and reported 90% and 75-80% degradation in 30 and 6 min, respectively. Kohtani et al (2003) modified the TiO 2 process by using a solar simulator and replacing the catalyst with BiVO 4 (capable of splitting water to H 2 and O 2 ) to study the degradation of 4-n-NP.…”

Fenton Oxidation Kinetics and Intermediates of Nonylphenol Ethoxylates

“…Their experimental results showed an NP decomposition rate of 55%, 74%, and 83% using membrane bioreactor, nanofiltration, and reverse osmosis methods, respectively. Ike et al (2002) applied ozone treatment to degrade NPEOs, resulting in a reduction of NP concentration by 70-80% in 6 min. There are disadvantages and advantages in removing NPEOs for each of the mentioned treatment process.…”

Modeling of nonylphenol degradation by photo-nanocatalytic process via multivariate approach

“…Recently, removal of aqueous NPs by electrochemical [8], ozonation [8][9][10][11][12], photolysis with UV [13], Photocatalysis with UV/TiO 2 and UV/BiVO 4 [12,[14][15][16], and Sonolysis with Fe(II) and Fe(III) [17] has been reported.…”