Effect of operational parameters on photocatalytic degradation of ethylparaben using rGO/TiO2 composite under UV radiation

The objective of this study was to analyze the influence of different operational variables (catalyst loading, initial EtP concentration, medium pH, the presence of anions and radical scavengers) on the performance of ethylparaben (EtP) photodegradation catalyzed with an rGO/TiO2 composite. EtP was...

Full description

Saved in:
Bibliographic Details
Published in:Environmental research 2021-09, Vol.200, p.111750-111750, Article 111750
Main Authors: Álvarez, Miguel A., Ruidíaz-Martínez, M., Rivera-Utrilla, José, Sánchez-Polo, Manuel, López-Ramón, M. Victoria
Format: Article
Language:English
Subjects:
Parabens
Photocatalysis
rGO/TiO2 composite
UV radiation
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:The objective of this study was to analyze the influence of different operational variables (catalyst loading, initial EtP concentration, medium pH, the presence of anions and radical scavengers) on the performance of ethylparaben (EtP) photodegradation catalyzed with an rGO/TiO2 composite. EtP was selected for study after analyzing the effect of paraben chain length on its catalytic photodegradation, finding that the photodegradation rate constant values of methyl-, ethyl-, and butyl-paraben are 0.050, 0.096, and 0.136 min−1, respectively. This indicates that the photodegradation rate constant of parabens is higher with longer alkyl chain, which augments its oxidation capacity. The percentage removal of EtP at 40 min increases from 66.3 to 98.6 % when the composite dose rises from 100 to 700 mg/L; however, an additional increase in the composite dose to 1000 mg/L does not substantively improve the photodegradation rate or percentage EtP removal (98.9 %). A rise in the initial EtP concentration from 15 to 100 mg/L reduces the percentage of degradation from 100 to 76.4 %. The percentage EtP degradation is lower with higher solution pH. The presence of HCO3− or Cl− anions in the medium reduces the degradation performance. Results obtained using positive hole and hydroxyl radical scavengers demonstrate that positive holes play an important role in EtP degradation. No degradation product evidences toxicity against the cultured human embryonic kidney cell line HEK-293. •The removal of parabens by UV-rGO/TiO2 system increased in the order MetP 
ISSN:0013-9351
1096-0953
DOI:10.1016/j.envres.2021.111750