Dataset Information

A clean and membrane-free chlor-alkali process with decoupled Cl2 and H2/NaOH production.

ABSTRACT: Existing chlor-alkali processes generally use asbestos, mercury or fluorine-containing ion-exchange membranes to separate the simultaneous chlorine production on the anode and hydrogen production on the cathode, and form sodium hydroxide in the electrolyte. Here, using the Na+ de-intercalation/intercalation of a Na0.44MnO2 electrode as a redox mediator, we decouple the chlor-alkali process into two independent steps: a H2 production step with the NaOH formation in the electrolyte and a Cl2 production step. The first step involves a cathodic H2 evolution reaction (H2O???H2) and an anodic Na+ de-intercalation reaction (Na0.44MnO2???Na0.44-xMnO2), during which NaOH is produced in the electrolyte solution. The second step depends on a cathodic Na+ intercalation reaction (Na0.44-xMnO2???Na0.44MnO2) and an anodic Cl2 production (Cl???Cl2). The cycle of the two steps provides a membrane-free process, which is potentially a promising direction for developing clean chlor-alkali technology.

SUBMITTER: Hou M

PROVIDER: S-EPMC5789859 | biostudies-other | 2018 Jan

REPOSITORIES: biostudies-other

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A clean and membrane-free chlor-alkali process with decoupled Cl2 and H2/NaOH production.

Hou Mengyan M Chen Long L Guo Zhaowei Z Dong Xiaoli X Wang Yonggang Y Xia Yongyao Y

Nature communications 20180130 1

Existing chlor-alkali processes generally use asbestos, mercury or fluorine-containing ion-exchange membranes to separate the simultaneous chlorine production on the anode and hydrogen production on the cathode, and form sodium hydroxide in the electrolyte. Here, using the Na+ de-intercalation/intercalation of a Na0.44MnO2 electrode as a redox mediator, we decouple the chlor-alkali process into two independent steps: a H2 production step with the NaOH ...[more]

PMID: 29382835

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Dataset Information

A clean and membrane-free chlor-alkali process with decoupled Cl2 and H2/NaOH production.

Publications

A clean and membrane-free chlor-alkali process with decoupled Cl<sub>2</sub> and H<sub>2</sub>/NaOH production.

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