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Author Mohandas, K. S. ♦ Sanil, N. ♦ Noel, M. ♦ Rodriguez, P.
Source CSIR-Central Electrochemical Research Institute
Content type Text
Publisher Springer Verlag
File Format PDF
Copyright Year ©2001
Language English
Subject Domain (in DDC) Natural sciences & mathematics ♦ Chemistry & allied sciences
Subject Keyword Electroorganic
Abstract The anodic behaviour of compacted graphite, graphite powder, glassy carbon and reticulated vitreous carbon electrodes in basic sodium chloroaluminate melt in the temperature range 428-573 K was studied using cyclic voltammetry. Chlorine evolution (+2.1 V vs Al) alone was the predominant reaction on the compact glassy carbon and fresh RVC electrodes. On compacted graphite, chlorine-assisted chloroaluminate intercalation was found to be a competitive process to the chlorine evolution. At high sweep rates, intercalation deintercalation near the graphite lattice edges occur faster than chlorine evolution. Subsequent intercalation, however, is a slow process. Chlorine evolution predominate at higher temperatures and at higher anodic potentials. On graphite powders, a more reversible free radical chlorine absorption desorption process also occurs in the potential region below chlorine evolution. The process occurs at the grain boundaries, edges and defects of the graphite powder material. Intercalation deintercalation processes are mainly responsible for the disintegration of graphitic materials in low-temperature chloroaluminate melts. Repeated intercalation deintercalation cycles result in the irreversible transformation of the electrode surface and electrode characteristics. The surface area of the electrode is increased Substantially on cycling. Electrode materials and operating conditions suitable for chlorine generation, intercalation deintercalation and chlorine absorption desorption and powder sources based on these processes are identified in this work.
Educational Use Research
Education Level UG and PG
Learning Resource Type Article
Publisher Date 2001-01-01
Journal PeerReviewed