Master of Science (MSc)
Faculty of Science
Dr. Scott D. Smith
Dr. Vladimir Kitaev
Numerous studies have been conducted on the removal of inorganic phosphorus (P) from wastewater, but a push towards lower effluent targets necessitates the additional removal of organic phosphorus as well. This study tested the ability of manganese oxide nanoparticles and iron oxide as potential catalysts for conversion of organic P into more readily removable inorganic forms, as well as the role of iron(III) chloride as coagulant to subsequently allow P to be removed by solids/liquid separation. Removals of 99-101% were obtained for model compounds at pH 5-7, 0.05-0.5 M H2O2, and Fe:P molar ratio of 5:1. Presence of H2O2 was found necessary to remove phosphonates in particular, increasing removal from 17 to 101%. Tests in real wastewaters containing organic P also showed higher removal with peroxide addition. Due to interference from H2O2, the standard method for P analysis in wastewater, colorimetry, could not be used as the primary analytical tool. An accurate and sensitive protocol using Inductively Coupled Plasma-Optical Emission Spectroscopy (ICP-OES) capable of low-level P detection was developed instead and compared to colorimetry using model organic P compounds and real wastewater samples. Detection limits for colorimetry and ICP-OES were 0.002 and 0.09 mg P/L respectively. ICP-OES gave analytical recoveries closest to 100% for model organic P compounds, but both methods gave highly variable data at concentrations below 0.15 mg P/L. ICP-OES seems promising for TP measurements given its high recoveries for model compounds, but more work is needed to improve its detection limit and sensitivity.
Ateeq, Farah, "Chemical Removal of Total Phosphorus from Wastewater to Low Levels and Its Analysis" (2016). Theses and Dissertations (Comprehensive). 1889.