Comparison of spectrophotometric and digital photometric methods for determining chemical oxygen demand

Abstract

© 2018, University of the Philippines Los Banos. All rights reserved. Visible spectrophotometry (VS) and digital photometry (DP) for determining chemical oxygen demand (COD) were compared; the latter method involved image processing of digital photographs of analyte solutions using RGB-AIC software. Statistical analysis showed that COD values of untreated and treated (trickling filter) wastewater samples from a hog slaughterhouse were not significantly different using VS and DP methods. The COD values were not significantly different among the treated samples as well using a* and L* plots. Tests for accuracy and repeatability of the DP method showed acceptable results. The calculated limit of detection (LOD) for DP was 0.73 mg L-1 while the LOD for VS was 0.33 mg L-1. The accuracy of the DP method was validated using glucose solutions of known COD values; t-tests performed at 95% confidence level showed no significant differences in COD values between (1) theory and experiment, (2) VS and DP and (3) a* and L* plots. These findings suggest that digital photometry is accurate and can be used as an equally accurate alternative to conventional spectrophotometry.

Source or Periodical Title

Journal of Environmental Science and Management

ISSN

1191144

Page

16-22

Document Type

Article

Subject

Chemical oxygen demand, Digital photometry, Image processing, Slaughterhouse wastewater, Visible spectrophotometry

This document is currently not available here.

Share

COinS