Abstract
Research and routine analysis laboratories produce sizeable amounts of residues as a result of experiments and by-products of chemical reactions. An example of that is soil analysis, in which a sulfochromic solution is used for the determination of organic matter content. This solution contains sodium dichromate and sulfuric acid, reagents that oxidize the soil’s organic fractions and contribute to the presence of chromium in laboratory residues discharged into the environment. In an attempt to find solutions to environmental problems, the aim of the present study was to quantitatively and qualitatively characterize chromium-contaminated residues generated during soil analysis. Therefore, management methods were proposed in order to recover chromium in its trivalent form (Cr3+) by precipitation. The use of biochemical oxygen demand, chemical oxygen demand, nitrogen, phosphorus, and metals to characterize the samples revealed the presence of 16.76 g L−1 of total chromium, with 4.19 g L−1 of Cr(VI). By means of ozonation, 68 % of the chromium was converted to liquid form and, after being reduced with bisulfite, it was turned into chromium sulfate (III). The remainder, 32 %, was kept with the other metals present in the solid form (sludge).
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: 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.
