Journal Article

Degradation and dechlorination of pentachlorophenol by microwave-activated persulfate

Zhao, Wei, Shi, Wenxiao, Xiao, Hao, Lin, Chunye, Liu, Xitao, Ma, Jun, Sun, Qu, Qi, Chengdu

2015

Overview

The degradation performance of pentachlorophenol (PCP) by the microwave-activated persulfate (MW/PS) process was investigated in this study. The results indicated that degradation efficiency of PCP in the MW/PS process followed pseudo-first-order kinetics, and compared with conventional heating, microwave heating has a special effect of increasing the reaction rate and reducing the process time. A higher persulfate concentration and reaction temperature accelerated the PCP degradation rate. Meanwhile, increasing the pH value and ionic strength of the phosphate buffer slowed down the degradation rate. The addition of ethanol and tert-butyl alcohol as hydroxyl radical and sulfate radical scavengers proved that the sulfate radicals were the dominant active species in the MW/PS process. Gas chromatography-mass spectrometry (GC-MS) was employed to identify the intermediate products, and then a plausible degradation pathway involving dechlorination, hydrolysis, and mineralization was proposed. The acute toxicity of PCP, as tested with Photobacterium phosphoreum , Vibrio fischeri , and Vibrio qinghaiensis , was negated quickly during the MW/PS process, which was in agreement with the nearly complete mineralization of PCP. These results showed that the MW/PS process could achieve a high mineralization level in a short time, which provided an efficient way for PCP elimination from wastewater.

• Publisher: Springer Berlin Heidelberg,Springer Nature B.V
• Subject: Acute toxicity / Aquatic Pollution / Aqueous solutions / Atmospheric Protection/Air Quality Control/Air Pollution / Biodegradation / Biofilms / Butanol / Chromatography / Dechlorination / Degradation / Earth and Environmental Science / Ecotoxicology / Environment / Environmental Chemistry / Environmental degradation / Environmental Health / Ethanol / Ethyl alcohol / free radical scavengers / Free radicals / Freshwater environments / Gas chromatography / Gas Chromatography-Mass Spectrometry / Halogenation / heat / Heating / hydrolysis / Hydroxyl Radical / Hydroxyl radicals / Ionic strength / Kinetics / Mass spectrometry / Mass spectroscopy / Microwave heating / Microwave radiation / microwave treatment / Microwaves / Mineralization / Osmolar Concentration / Oxidation / Oxidation-Reduction / Pentachlorophenol / Pentachlorophenol - chemistry / Pentachlorophenol - toxicity / Pesticide toxicity / Pesticides / Photobacterium - drug effects / Photobacterium phosphoreum / Pollutants / Radicals / Research Article / Scientific imaging / Sulfates / Sulfates - chemistry / temperature / tert-Butanol / Toxicity / Vibrio / Vibrio - drug effects / Vibrio fischeri / Vibrio qinghaiensis / Waste Water Technology / wastewater / Water Management / Water Pollutants, Chemical - chemistry / Water Pollutants, Chemical - toxicity / Water Pollution Control