Effectiveness and mechanism of cyanide remediation from contaminated soils using thermally activated persulfate

Antibiotic residues and antibiotic resistance genes (ARGs) pose a great threat to public health and food security via the horizontal transfer in the food production chain. Oxidative degradation of amoxicillin (AMO) in aqueous solution by thermally activated persulfate (TAP) was investigated. The AMO degradation followed a pseudo-first-order kinetic model at all tested conditions. The pseudo-first-order rate constants of AMO degradation well-fitted the Arrhenius equation when the reaction temperature ranged from 35°C to 60°C, with the apparent activate energy of 126.9 kJ·mol−1. High reaction temperature, high initial persulfate concentration, low pH, high Cl− concentration, and humic acid (HA) concentration increased the AMO degradation efficiency. The EPR test demonstrated that both ·OH and SO4·− were generated in the TAP system, and the radical scavenging test identified that the predominant reactive radical species were SO4·− in aqueous solution without adjusting the solution pH. In groundwater and drinking water, AMO degradation suggested that TAP could be a reliable technology for water remediation contaminated by AMO in practice.

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Degradation of Triclosan in soils by thermally activated persulfate under conditions representative of in situ chemical oxidation (ISCO)

Chemical Engineering Journal ◽

10.1016/j.cej.2019.03.084 ◽

2019 ◽

Vol 369 ◽

pp. 344-352 ◽

Cited By ~ 14

Author(s):

Liwei Chen ◽

Xiaoxin Hu ◽

Tianming Cai ◽

Ying Yang ◽

Rudong Zhao ◽

...

Keyword(s):

Chemical Oxidation ◽

In Situ Chemical Oxidation ◽

Thermally Activated ◽

Activated Persulfate

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Thermally activated persulfate oxidation of NAPL chlorinated organic compounds: effect of soil composition on oxidant demand in different soil-persulfate systems

Water Science & Technology ◽

10.2166/wst.2017.052 ◽

2017 ◽

Vol 75 (8) ◽

pp. 1794-1803 ◽

Cited By ~ 1

Author(s):

Jialu Liu ◽

Zhehua Liu ◽

Fengjun Zhang ◽

Xiaosi Su ◽

Cong Lyu

Keyword(s):

Organic Compounds ◽

Mineral Content ◽

Removal Rate ◽

Soil Types ◽

Soil Composition ◽

Persulfate Oxidation ◽

Chlorinated Volatile Organic Compounds ◽

Thermally Activated ◽

Soil Components ◽

Activated Persulfate

This study investigates the interaction of persulfate with soil components and chlorinated volatile organic compounds (CVOCs), using thermally activated persulfate oxidation in three soil types: high sand content; high clay content; and paddy field soil. The effect of soil composition on the available oxidant demand and CVOC removal rate was evaluated. Results suggest that the treatment efficiency of CVOCs in soil can be ranked as follows: cis-1,2-dichloroethene > trichloroethylene > 1,2-dichloroethane > 1,1,1-trichloroethane. The reactions of soil components with persulfate, shown by the reduction in soil phase natural organics and mineral content, occurred in parallel with persulfate oxidation of CVOCs. Natural oxidant demand from the reaction of soil components with persulfate exerted a large relative contribution to the total oxidant demand. The main influencing factor in oxidant demand in paddy-soil-persulfate systems was natural organics, rather than mineral content as seen with sand and clay soil types exposed to the persulfate system. The competition between CVOCs and soil components for oxidation by persulfate indicates that soil composition exhibits a considerable influence on the available oxidant demand and CVOC removal efficiency. Therefore, soil composition of natural organics and mineral content is a critical factor in estimating the oxidation efficiency of in-situ remediation systems.

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