Chemical oxygen demand analysis of wastewater using trivalent manganese oxidant with chloride removal by sodium bismuthate pretreatment
Current chemical oxygen demand (COD) analyses generate wastes containing hexavalent and trivalent chromium, mercury, and silver. Waste disposal is difficult, expensive, and poses environmental hazards. A new COD test is proposed that eliminates these metals and shortens analysis time, where trivalen...
Veröffentlicht in: | Water environment research : a research publication of the Water Environment Federation. - 1998. - 73(2001), 1 vom: 03. Jan., Seite 63-71 |
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1. Verfasser: | |
Weitere Verfasser: | , |
Format: | Aufsatz |
Sprache: | English |
Veröffentlicht: |
2001
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Zugriff auf das übergeordnete Werk: | Water environment research : a research publication of the Water Environment Federation |
Schlagworte: | Journal Article Carcinogens, Environmental Chromium 0R0008Q3JB chromium hexavalent ion 18540-29-9 Silver 3M4G523W1G Manganese 42Z2K6ZL8P mehr... |
Zusammenfassung: | Current chemical oxygen demand (COD) analyses generate wastes containing hexavalent and trivalent chromium, mercury, and silver. Waste disposal is difficult, expensive, and poses environmental hazards. A new COD test is proposed that eliminates these metals and shortens analysis time, where trivalent manganese oxidant replaces hexavalent chromium (dichromate). A silver catalyst is not required. Optional pretreatment removes chloride via oxidation to chlorine using sodium bismuthate, eliminating the need for mercury. Sample aqueous and solid components are separated for chloride removal, then recombined for total COD measurement. Soluble and nonsoluble COD can be determined separately. Digestion at 150 degrees C is complete in 1 hour. Results are determined by titration or by spectrophotometric reading. Test wastes contain none of the metals regulated for disposal under the Resource Conservation and Recovery Act. Results are shown for selected organic compounds and various wastewaters. Statistical comparisons are made with dichromate COD and biochemical oxygen demand (BOD5) test values |
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Beschreibung: | Date Completed 25.10.2001 Date Revised 21.09.2019 published: Print Citation Status MEDLINE |
ISSN: | 1554-7531 |