ISSN print edition: 0366-6352 ISSN electronic edition: 1336-9075 Registr. No.: MK SR 9/7 Published monthly

Improvements to CO2 headspace biodegradability test

Hana Kaňková, Vladimír Sýkora, Hana Kujalová, and Michal Cypris

Institute of Chemical Technology, Faculty of Environmental Technology, Department of Water Technology and Environmental Engineering, Technická 5, 166 28 Prague 6, Czech Republic

E-mail: vladimir.sykora@vscht.cz

Abstract: This study proposes changes to the design and evaluation of the CO₂ headspace test, which is used as a simple method for assessment of the complete biodegradability of surfactants. It presents a modified equation for the calculation of biodegradation. It is proposed that the solution of 7 mol L⁻¹ sodium hydroxide commonly used in the process involving alkalinisation of the vial contents be replaced with 15 mol L⁻¹ sodium hydroxide. The use of the higher hydroxide concentration leads to a significant reduction in the value of the blank CO₂ headspace test.

Keywords: CO2 headspace test – complete biodegradation – determination of carbon dioxide increase – inorganic carbon

Full paper is available at www.springerlink.com.

DOI: 10.1515/chempap-2015-0008

Chemical Papers 69 (2) 376–379 (2015)