Oxidation of odorous and nonodorous algal metabolites by permanganate, chlorine, and chlorine dioxide

Abstract

The six algal metabolites, at concentrations of 20-225 μg/l, were oxidized with potassium permanganate, chlorine, or chlorine dioxide at doses of 0.25-3 mg/l. Flavor profile analysis (FPA) was used to determine the odors of the solutions before and after oxidation. Linoleic and palmitic acids, which are odorless compounds, were oxidized to odorous products by all three oxidants. The odor intensity of β-cyclocitral (grape, sweet tobacco) and phenethyl alcohol (rose, floral) was only slightly decreased by any of the oxidants. Oxidation by permanganate or chlorine either eliminated or greatly reduced the odors associated with linolenic acid (watermelon) and 2t,6c-nonadienal (cucumber); chlorine dioxide was ineffective at reducing the cucumber odor of 2t,6c-nonadienal. Oxidation, at doses typically applied for drinking water treatment, can result in the destruction of certain algae-related odors but in the formation of other odors.

Catalyzing the oxidation of sulfamethoxazole by permanganate using molecular sieves supported ruthenium nanoparticles

“…Permanganate oxidation has been already widely used in water utilities over the past decades for control of dissolved Mn(II), taste and odor compounds, and cyanotoxins, due to its comparative stability, ease of handling, and relatively low cost (Vanbenschoten et al, 1992;Dietrich et al, 1995;Rodriguez et al, 2007). In recent years, the potential application of permanganate for oxidative removal of emerging pollutants during water and wastewater treatment has received great attention (Jiang et al, 2009Jiang et al, 2012;Zhang et al, 2013a).…”

Chemical species

“…Olfactory GC and GCIMS were applied to characterize . Changes in odor types and intensities can be used as indicators of water treatment practices (Dietrich et al 1995); odors were demonstrated to appear, disappear or change when oxidants were added to water samples. A procedure for developing odor standards, based on extraction and analysis of odorous materials, was demonstrated for identifying grassy odors in fresh grass; cis-3-hexenylacetate was demonstrated to be a key odor compound (Khiari et aI., 1995).…”

Les goûts et les odeurs dans l’eau potable : revue des composés responsables et des techniques de mesure

“…Les composés produits par les algues à l'origine des goûts et des odeurs dans l'eau potable comprennent des aldéhydes, des alcanes, des alcènes, des alcools et des esters (DIETRICH et al, 1995 (BÜDEL et al, 2005;WEHR et SHEATH 2003).…”