A study has been carried out relating to various methods of detinning scrap tinplate. Assessments of chemical and electrochemical techniques have been made with special relevance to recycling of the used can. It has been found that the electrolytic dissolution of both tin and the iron-tin intermetallic compound is Coulombic in alkaline conditions. The addition of oxidising agents does not generally increase the rate of alloy dissolution under alkaline electrochemical conditions, although free tin dissolution is aided. Parameters associated with an industrial electrolytic detinning plant have been studied, and it was found that optimum temperature and current density values exist for the dissolution of alloy in alkali. The effect of thermally treating tinplate has been studied, and some reactions of the intermetallic layer have shown the possible presence of other stoichiometric alloys. Activation energies for one alloy (FeSn2) have been calculated at above and below 232°C. Alkaline attack of the intermetallic layer has been shown to be very similar to that of iron. The presence of lead and calcium has been found in tinplate; the relevance of the apparent lead content is discussed and assessed. Conditions have been established for a viable industrial process for the reclamation of tin and clean scrap steel from urban refuse. Necessary instrumentation for an industrial process is discussed.
| Identifer | oai:union.ndltd.org:bl.uk/oai:ethos.bl.uk:496193 |
| Date | January 1980 |
| Creators | Crichton, Trevor John |
| Publisher | University of Birmingham |
| Source Sets | Ethos UK |
| Detected Language | English |
| Type | Electronic Thesis or Dissertation |
| Source | http://etheses.bham.ac.uk//id/eprint/8694/ |
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