Abstract
A new variant of the method for chemical oxygen demand (COD; 20–1100 mg O 2 l −1) determination in environmental waters is described. The method is based on determination of excess Cr(VI) in a mixed-acid (H 3PO 4–H 2SO 4) digestion solution by single sweep polarography instead of titrimetry; COD is measured indirectly. The reflux time is shortened to 15 min by mixed-acid digestion. The effects of mixed-acid concentration, reflux time, amounts of dichromate, supporting electrolyte, and interfering substances on COD determination are discussed. Preliminary application are made to waste waters and sewage. The results obtained are in good agreement with those given by the standard reflux method with a relative error<1.5%.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.