Dataset Information

Comparative Analysis of Photocatalytic and Electrochemical Degradation of 4-Ethylphenol in Saline Conditions.

ABSTRACT: We evaluated electrochemical degradation (ECD) and photocatalytic degradation (PCD) technologies for saline water purification, with a focus on rate comparison and formation and degradation of chlorinated aromatic intermediates using the same non-chlorinated parent compound, 4-ethylphenol (4EP). At 15 mA·cm-2, and in the absence of chloride (0.6 mol·L-1 NaNO3 was used as supporting electrolyte), ECD resulted in an apparent zero-order rate of 30 ?mol L-1·h-1, whereas rates of ?300 ?mol L-1·h-1 and ?3750 ?mol L-1·h-1 were computed for low (0.03 mol·L-1) and high (0.6 mol·L-1) NaCl concentration, respectively. For PCD, initial rates of ?330 ?mol L-1·h-1 and 205 ?mol L-1·h-1 were found for low and high NaCl concentrations, at a photocatalyst (TiO2) concentration of 0.5 g·L-1, and illumination at ?max ? 375 nm, with an intensity ?0.32 mW·cm-2. In the chlorine mediated ECD approach, significant quantities of free chlorine (hypochlorite, Cl2) and chlorinated hydrocarbons were formed in solution, while photocatalytic degradation did not show the formation of free chlorine, nor chlorine-containing intermediates, and resulted in better removal of non-purgeable hydrocarbons than ECD. The origin of the minimal formation of free chlorine and chlorinated compounds in photocatalytic degradation is discussed based on photoelectrochemical results and existing literature, and explained by a chloride-mediated surface-charge recombination mechanism.

SUBMITTER: Bruninghoff R

PROVIDER: S-EPMC6686150 | biostudies-literature | 2019 Aug

REPOSITORIES: biostudies-literature

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Comparative Analysis of Photocatalytic and Electrochemical Degradation of 4-Ethylphenol in Saline Conditions.

Brüninghoff Robert R van Duijne Alyssa K AK Braakhuis Lucas L Saha Pradip P Jeremiasse Adriaan W AW Mei Bastian B Mul Guido G

Environmental science & technology 20190722 15

We evaluated electrochemical degradation (ECD) and photocatalytic degradation (PCD) technologies for saline water purification, with a focus on rate comparison and formation and degradation of chlorinated aromatic intermediates using the same non-chlorinated parent compound, 4-ethylphenol (4EP). At 15 mA·cm-2, and in the absence of chloride (0.6 mol·L-1 NaNO3 was used as supporting electrolyte), ECD resulted in an apparent zero-order rate of 30 μmol L-1</sup ...[more]

PMID: 31282148

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Dataset Information

Comparative Analysis of Photocatalytic and Electrochemical Degradation of 4-Ethylphenol in Saline Conditions.

Publications

Comparative Analysis of Photocatalytic and Electrochemical Degradation of 4-Ethylphenol in Saline Conditions.

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