Operando Studies of Iodine Species in an Advanced Oxidative Water Treatment Reactor

We present an electrochemical advanced oxidation process (eAOP) reactor employing expanded graphite, potassium iodide (KI), and electrical current, which demonstrates an exceptionally high rate of inactivation of E. coli (6log reduction in viable cells) at low current density 0.6 mA/cm^2), with low contact time (5 minutes) and low concentration of KI (10 ppm). Operando X-ray fluorescence mapping is used to show the distribution of iodine species in the reactor, and operando X-ray absorption spectroscopy in the anodic chamber reveals iodine species with higher effective oxidation state than periodate. Operando electrochemical measurements confirm the conditions in the anodic chambers are favourable for the creation of highly oxidized iodine products. The killing efficiency of this new eAOP reactor far exceeds that expected from either traditional iodine-based electrochemical water treatment or advanced oxidation systems alone, a phenomenon that may be associated with the production of highly oxidized iodine species reported here.

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Operando Studies of Iodine Species in an Advanced Oxidative Water Treatment Reactor

10.26434/chemrxiv.13611347.v1 ◽

2021 ◽

Author(s):

Ahmed Moustafa ◽

Alex Evans ◽

Simmon Hofstetter ◽

Jenny Boutros ◽

Parastoo Pourrezaei ◽

...

Keyword(s):

Water Treatment ◽

Advanced Oxidation Process ◽

Expanded Graphite ◽

Advanced Oxidation ◽

Electrical Current ◽

High Rate ◽

X Ray ◽

E Coli ◽

Iodine Species ◽

Anodic Chamber

We present an electrochemical advanced oxidation process (eAOP) reactor employing expanded graphite, potassium iodide (KI), and electrical current, which demonstrates an exceptionally high rate of inactivation of E. coli (6log reduction in viable cells) at low current density 0.6 mA/cm^2), with low contact time (5 minutes) and low concentration of KI (10 ppm). Operando X-ray fluorescence mapping is used to show the distribution of iodine species in the reactor, and operando X-ray absorption spectroscopy in the anodic chamber reveals iodine species with higher effective oxidation state than periodate. Operando electrochemical measurements confirm the conditions in the anodic chambers are favourable for the creation of highly oxidized iodine products. The killing efficiency of this new eAOP reactor far exceeds that expected from either traditional iodine-based electrochemical water treatment or advanced oxidation systems alone, a phenomenon that may be associated with the production of highly oxidized iodine species reported here.

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Monitoring of iodine species during water purification at a public water treatment plant in Japan

Water Science & Technology Water Supply ◽

10.2166/ws.2018.104 ◽

2018 ◽

Vol 19 (2) ◽

pp. 580-587

Author(s):

Sho Nishida ◽

Maki Asami ◽

Naoya Ohata ◽

Jun Horigome ◽

Naoki Furuta

Keyword(s):

Water Treatment ◽

Humic Substances ◽

Treatment Process ◽

Treatment Plant ◽

Water Treatment Plant ◽

Size Exclusion ◽

Ozone Treatment ◽

Raw Water ◽

Iodine Species ◽

Water Treatment Process

Abstract Iodine is an essential element for humans; however, it can be toxic depending on its chemical form. A variety of toxic and non-toxic iodine species have been identified in environmental water and in the drinking water produced by public water treatment plants. Here, we examined the change of iodine species during the water treatment process at a public water treatment plant in Japan. Samples of raw water and of treated water immediately after each of eight treatment stages comprising the treatment process were collected, and a speciation analysis was conducted by means of ion chromatography– and size-exclusion chromatography–inductively coupled plasma mass spectrometry. In the raw water, iodine was found mainly as iodide or iodinated humic substances that were ultimately oxidized and transformed into iodate, a form non-toxic to humans, by two independent oxidation stages in the water treatment process – ozone treatment and chlorine treatment. No disinfection byproducts were detected at any stage of the treatment process. Fluorescence spectrometry with multivariate analysis revealed that humic substances were markedly decreased by ozone treatment, but not by chlorine treatment. The present results show that, at the plant-scale, ozone treatment is an effective means of removing toxic iodine species from raw water.

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Interface Science in Drinking Water Treatment - Theory and Application

10.1016/s1573-4285(06)x8069-9 ◽

2006 ◽

Keyword(s):

Drinking Water ◽

Water Treatment ◽

Drinking Water Treatment ◽

Interface Science ◽

Treatment Theory

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Modeling and Control of a Chemical Waste Water Treatment Plant

Computers & Chemical Engineering ◽

10.1016/s0098-1354(97)00171-3 ◽

1997 ◽

Vol 21 (1-2) ◽

pp. S947-S952 ◽

Cited By ~ 2

Author(s):

R Miller

Keyword(s):

Waste Water ◽

Water Treatment ◽

Waste Water Treatment ◽

Treatment Plant ◽

Water Treatment Plant ◽

Waste Water Treatment Plant ◽

Chemical Waste ◽

Modeling And Control ◽

And Control

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Optimization of Residence Time Distribution in Small Water Treatment Systems

Computational Fluid Dynamics ◽

10.1061/9780784415313.ch15 ◽

2019 ◽

pp. 123-130

Keyword(s):

Water Treatment ◽

Residence Time ◽

Time Distribution ◽

Residence Time Distribution ◽

Small Water

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To the issue of water treatment by hydrocyclone on the systems of the combined irrigation

Melioration and Water Management ◽

10.32962/0235-2524-2019-2-21-25 ◽

2020 ◽

Vol 0 (2) ◽

pp. 21-25

Author(s):

Nikolay Dubenok ◽

Andrey Novikov ◽

Sergei Borodychev ◽

Maria Lamskova

Keyword(s):

Water Treatment ◽

Organic Compounds ◽

Irrigation Water ◽

Irrigation System ◽

Petroleum Products ◽

Cylindrical Part ◽

Agricultural Landscapes ◽

Treatment Unit ◽

Drain Pipe ◽

Irrigation Network

At the stage of water treatment for irrigation systems, the efficiency capture coarse and fine mechanical impurities, as well as oil products and organic compounds affects the reliability of the equipment of the irrigation network and the safety of energy exchange processes in irrigated agricultural landscapes. The violation of work irrigation system can cause disruptions in irrigation schedules of agricultural crops, crop shortages, degradation phenomena on the soil and ecological tension. For the combined irrigation system, a water treatment unit has been developed, representing a hydrocyclone apparatus with a pipe filter in the case. For the capacity of 250 m3/h the main geometrical dimensions of hydrocyclone have been calculated. To organize the capture petroleum products and organic compounds, it has been proposed a modernization of a hydrocyclone unit, consisting in dividing the cylindrical part of the apparatus into two section. The first is section is for input irrigation water, the second one is for additional drainage of clarified irrigation water after sorption purification by the filter, placed on the disk and installed coaxially with the drain pipe and the pipe filter.

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