Validation of a Modified Procedure for the determination of Chemical Oxygen Demand using standard dichromate method in industrial wastewater samples with high calcium chloride content

A Gnanavelu; T S Shanmuganathan; V Deepesh; S Suresh

doi:10.17485/IJST/v14i29.1412

Article

Validation of a Modified Procedure for the determination of Chemical Oxygen Demand using standard dichromate method in industrial wastewater samples with high calcium chloride content

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Indian Journal of Science and Technology

DOI: 10.17485/IJST/v14i29.1412

Year: 2021, Volume: 14, Issue: 29, Pages: 2391-2399

Original Article

Validation of a Modified Procedure for the determination of Chemical Oxygen Demand using standard dichromate method in industrial wastewater samples with high calcium chloride content

A Gnanavelu¹, T S Shanmuganathan², V Deepesh^1*, S Suresh¹

¹Regional Laboratory, Central Pollution Control Board, Regional Directorate, Bengaluru, 560079, Karnataka, India
²QA Laboratory, Manali Petrochemicals Ltd, Chennai, India

*Corresponding Author
Email: [email protected]

Received Date:31 July 2021, Accepted Date:19 August 2021, Published Date:30 August 2021

This work is licensed under a Creative Commons Attribution 4.0 International License.

Abstract

Background/ Objectives: Chemical Oxygen Demand (COD) is a widely used aggregate organic pollutant index in national discharge standards and is one of the critical parameters for water quality assessment. The conventional COD determination by wet oxidative method encounters the problem of chloride interference in water samples with high chloride content. The dichromate reflux method oxidizes 85-95% of organic matter and also 100% of chloride ions in the samples, without an appropriate chloride masking strategy. The standard method cannot measure COD accurately in samples containing more than 2000 mg L-1 chloride. The present study demonstrates and validates a modified procedure for the determination of COD in industrial sample with high calcium chloride content and low organic load. Method: Petrochemical industries manufacturing Propylene Oxide and Propylene Glycol via chlorohydrin route generate wastewater with high calcium chloride content. Due to high chloride content, the standard analysis method could not produce reliable data for COD values with known precision and accuracy. The standard method based on dichromate was modified, with an additional mixing step for a specified time to enhance the chloride masking by mercuric sulphate. Undiluted sample (20 mL) was mixed with the required amount of mercuric sulpahte to maintain 10:1 ratio to chloride content and 10 mL of sulphuric acid at 150-175 RPM for 20 minutes at room temperature to increase the contact time/ chloride masking. Method validation attributes of the modified procedure were assessed and found to be complying with the acceptance criteria. Findings: We developed a modified procedure for the standard dichromate based chemical oxygen demand (COD) determination in industrial wastewater samples rich in calcium chloride. An additional mixing step is introduced in the standard procedure to enhance the chloride masking with mercuric sulphate in samples containing high chloride. The amended procedure resulted in accurate COD values in samples with low organic load, rich in calcium chloride and the modifiedmethod was successfully validated. Novelty: The modified procedure with mixing step to enhance chloride masking was found to be satisfactory for determining COD in calcium chloride-rich industrial effluent.

Keywords: Chemical Oxygen Demand (COD); Chloride interference; Modification of standard method; Wastewater analysis; Calcium chloride; Validation

References

Latif U, Dickert FL. Chemical Oxygen Demand. Nanostructure Science and Technology. 2015;p. 719–728. Available from: https://doi.org/10.1007/978-1-4939-1301-5_1
Kim BR. Effect of Ammonia on COD Analysis. Journal WPCF. 1989;61(5):614–617. Available from: http://www.jstor.org/stable/25043656
Vyrides I, Stuckey D. A modified method for the determination of chemical oxygen demand (COD) for samples with high salinity and low organics. Bioresource Technology. 2009;100(2):979–982. Available from: https://doi.org/10.1016/j.biortech.2008.06.038
Li J, Luo G, He L, Xu J, Lyu J. Analytical Approaches for Determining Chemical Oxygen Demand in Water Bodies: A Review. Critical Reviews in Analytical Chemistry. 2018;48(1):47–65. doi: 10.1080/10408347.2017.1370670
Yao N, Wang J, Zhou Y. Rapid Determination of the Chemical Oxygen Demand of Water Using a Thermal Biosensor. Sensors. 2014;14:9949–9960. doi: 10.3390/s140609949
Aniyikaiye TE, Oluseyi T, Odiyo JO, Edokpayi JN. Physico-Chemical Analysis of Wastewater Discharge from Selected Paint Industries in Lagos, Nigeria . International Journal of Environmental Research and Public Health. 2019;16:1235. Available from: https://doi.org/10.3390/ijerph16071235
Kayaalp N, Ersahin ME, Ozgun H, Ismail K, Kinaci C. A new approach for chemical oxygen demand (COD) measurement at high salinity and low organic matter samples. Environmental Science and Pollution Research. 2010;17:1547–1552. doi: 10.1007/s11356-010-0341-z
ASTM. Standard Test Method for Total Oxygen Demand in Water (D6238-98) 2017. Available from: https://www.astm.org/Standards/D6238.html
Geerdink R, Hurk RSVD, Epema O. Chemical oxygen demand: Historical perspectives and future challenges. Analytica Chimica Acta. 2017;961:1–11. doi: 10.1016/j.aca.2017.01.009
Dedkov Y, Elizarova O. Dichromate method for the determination of chemical oxygen demand. Journal of Analytical Chemistry. 2000;55(8):777–781. doi: 10.1007/BF02757915
Long H, Gu H, Jalalvand A, Zhang S, Liu Y, Chen W. Prediction of chemical oxygen demand (COD) with total organic carbon (TOC) to eliminate the interferences of high concentration of chloride ion in oilfield wastewaters. International Journal of Environmental Analytical Chemistry. 2019;101(9):1209–1219. Available from: https://doi.org/10.1080/03067319.2019.1678604
Kolb M, Bahadir M, Teichgräber B. Determination of chemical oxygen demand (COD) using an alternative wet chemical method free of mercury and dichromate. Water Research. 2017;122:645–654. Available from: https://doi.org/10.1016/j.watres.2017.06.034
Kim H, Lim H, Colosimo M. Determination of chemical oxygen demand (COD) using ultrasound digestion and oxidation-reduction potential-based titration. Journal of Environmental Science and Health, Part A. 2007;42(11):1665–1670. doi: 10.1080/10934520701518190
Baird RB, Eaton AD, Rice EW. Standard methods for the examination of water and wastewater (23). Washington. APHA. 2017.
Shi X, Huang S, Yeap T, Ong S. Ng HA method to eliminate bromide interference on standard COD test for bromide-rich industrial wastewater. Chemosphere. 2020;240:124804. Available from: https://doi.org/10.1016/j.chemosphere.2019.124804
Burns E, Marshall C. Correction for Chloride Interference in the Chemical Oxygen Demand Test. Journal (Water Pollution Control Federation). 1965;37(12):1716–1721.
Baumann F. Dichromate reflux chemical oxygen demand. Proposed method for chloride correction in highly saline wastes. Analytical Chemistry. 1974;46(9):1336–1338. doi: 10.1021/ac60345a039
Drolc A, Cotman M, Roš M. Uncertainty of chemical oxygen demand determination in wastewater samples. Accreditation and Quality Assurance. 2003;8(3-4):138–145. Available from: https://doi.org/10.1007/s00769-002-0565-9
Shabir G, Lough WJ, Arain S, Bradshaw T. Evaluation and Application of Best Practice in Analytical Method Validation. Journal of Liquid Chromatography & Related Technologies. 2007;30(3):311–333. Available from: https://doi.org/10.1080/10826070601084753
Gupta P. Method Validation of Analytical Procedures. PharmaTutor. 2015;3(1):32–39. Available from: https://www.pharmatutor.org/articles/method-validation-analytical-procedures
Indian standard IS 5420 (part 2): Guide on precision of test methods, Part II: inter laboratory testing. Bureau of Indian Standards (BIS). 1973. Available from: https://www.services.bis.gov.in:8071/php/BIS/bisconnect/pow/is_details?IDS=MTk4MTY%3D
Magnusson B, Örnemark U. Eurachem Guide: The Fitness for Purpose of Analytical Methods – A Laboratory Guide to Method Validation and Related Topics. (Vol. 2) 2014.
WHO. Guidelines on Validation-Appendix 4: Analytical method validation. 2018. Available from: https://www.who.int/medicines/areas/quality_safety/quality_assurance/28092018Guideline_Validation_AnalyticalMethodValidation-Appendix4_QAS16-671.pdf
WHO. Expert Committee on Specifications for Pharmaceutical Preparations: Fifty-third report. World Health Organization (WHO) 2019. Available from: https://apps.who.int/iris/rest/bitstreams/1217390/retrieve
Horwitz W, Albert R. The Horwitz Ratio (HorRat): A Useful Index of Method Performance with Respect to Precision. Journal of AOAC INTERNATIONAL. 2006;89(4):1095–1109. Available from: https://doi.org/10.1093/jaoac/89.4.1095
AI. Guidelines for standard method performance requirements - Appendix F. Available from: http://www.eoma.aoac.org/app_f.pdf
Tsonis S. A Modified Method for The Determination of Chemical Oxygen Demand in Sea Water. (pp. 723-729) Southampton. 1993.
Hu Z, Grasso D. Water Analysis - Chemical Oxygen Demand. In: Worsfold P, AT, CP., eds. Encyclopedia of Analytical Science. (pp. 325-330) Elsevier. 2005.
Zhang S, Chen W, Liu Y, Luo P, Gu H. A Modified Method for the Accurate Determination of Chemical Oxygen Demand (COD) in High Chloride Oilfield Wastewater. Open Journal of Yangtze Oil and Gas. 2018;3:263–277. Available from: https://doi.org/10.4236/ojogas.2018.34023
Vaidya B, Watson S, Coldiron S, Porter M. Reduction of chloride ion interference in chemical oxygen demand (COD) determinations using bismuth-based adsorbents. Analytica Chimica Acta. 1997;357(1-2):541–543. Available from: https://doi.org/10.1016/S0003-2670(97)00541-2
Li J, Li L, Zheng L, Xian Y, JL. Rh2O3/Ti electrode preparation using laser anneal and its application to the determination of chemical oxygen demand. Measurement Science and Technology. 2006;17(7):1995–2000. Available from: https://iopscience.iop.org/article/10.1088/0957-0233/17/7/044/meta

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© 2021 Gnanavelu et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. Published By Indian Society for Education and Environment (iSee)