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Thermal Behavior of Iron Arsenides Under Non-Oxidizing Conditions.

ABSTRACT: Fe2As has been studied in situ by synchrotron powder X-ray diffraction (PXRD) over the range of temperatures 25-850 °C and under a neutral atmosphere to understand its thermal behavior, which is potentially important for gold extraction. For the first time, incongruent high-temperature reactions of Fe2As are observed as it breaks down and the existence of a previously undiscovered high-temperature FeAs phase with an NiAs-type structure has been determined experimentally. No evidence has been found for the existence of the high-temperature Fe3As2 phase. Hence, the previously published phase diagram for the Fe-As system has to be modified accordingly.

SUBMITTER: Seitkan A

PROVIDER: S-EPMC7114163 | biostudies-literature | 2020 Mar

REPOSITORIES: biostudies-literature

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Thermal Behavior of Iron Arsenides Under Non-Oxidizing Conditions.

Seitkan Ainur A Lampronti Giulio I GI Widmer Remo N RN Casati Nicola P M NPM Redfern Simon A T SAT

ACS omega 20200320 12

Fe2As has been studied in situ by synchrotron powder X-ray diffraction (PXRD) over the range of temperatures 25-850 °C and under a neutral atmosphere to understand its thermal behavior, which is potentially important for gold extraction. For the first time, incongruent high-temperature reactions of Fe2As are observed as it breaks down and the existence of a previously undiscovered high-temperature FeAs phase with an NiAs-type structure has been determined experimenta ...[more]

PMID: 32258877

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