Release Time:2019-03-12  Hits:

Indexed by: Journal Article

Date of Publication: 2018-03-06

Journal: ENVIRONMENTAL SCIENCE & TECHNOLOGY

Included Journals: PubMed、EI、SCIE

Volume: 52

Issue: 5

Page Number: 2790-2799

ISSN: 0013-936X

Abstract: Aqueous center dot OH reaction rate constants (k(OH)) for organophosphate esters (OPEs) are essential for assessing their environmental fate and removal potential in advanced oxidation processes (AOPs). Herein experimental and in silico approaches were adopted to obtain k(OH) values for a variety of OPEs. The determined k(OH) for 18 OPEs varies from 4.0 X 10(8) M-1 s(-1) to 1.6 X 10(10) s(-1). Based on the experimental k(OH) values, a quantitative structure-activity relationship model that involves molecular structural information on the number of heavy atoms, content index, and the most negative charge of C atoms was developed for predicting k(OH) of other OPEs. Furthermore, appropriate density functional theory (DFT) and solvation models were selected, which together with transition state theory were employed to predict k(OH) of three representative OPEs. The deviation between the DFT calculated and the experimental k(OH) values (k(cal)/k(exp)) is within 2. Half-lives of the OPEs were estimated to be 0.5-22791.3 days in natural waters and 0.044-19.7 s in AOPs, indicating the OPEs are potentially persistent in natural waters and can be quickly eliminated by AOPs. The determined k(OH) values and the in silico methods offer a scientific base for assessing OPEs fate in aquatic environments.