Removal of Flotation Collector O-Isopropyl-N-ethylthionocarbamate from Wastewater

Abstract

Flotation collector O-isopropyl N-ethylthionocarbamate (IPETC) is widely used for separation of sulfide ores. Its removal from water by several oxidation processes was studied. Photocatalytic oxidation with air in the presence of iron salts, utilizing solar irradiation or artificial UV-A light is very efficient. Oxidation leads through the formation of O-isopropyl N-ethylcarbamate and several other reaction intermediates to total decomposition of organic compound in the final stage in 1 day. Similar results were obtained with a Fenton type oxidation with hydrogen peroxide and iron salts. Treatment with sodium hypochlorite yields mainly O-isopropyl N-ethylcarbamate. The formation of this compound in wastewaters can be of concern, since simple alkyl carbamates are cancer suspect agents.

Thioether-functionalized cellulose for the fabrication of oxidation-responsive biomaterial coatings and films

“…Under the 1% H2O2 oxidation conditions, the FTIR spectra within the thiocarbamoyl region showed a notable increase in the intensity of the 1710 cm -1 stretch and a concurrent reduction in the 1535 cm -1 stretch which is consistent with the sulfur atom in the thiocarbamoyl being substituted by an oxygen atom to form -O-CO-NH-(Fig. 1G) (61). Despite these changes, there was preserved total integration of the two stretches within the thiocarbamoyl region (Fig.…”

“…1F, S2). By FTIR, HECMTP showed emergent -CS-NH-and -O-CS-(thiocarbamoyl) stretches at 1535 cm -1 and 1710 cm -1 respectively following MTP addition (61,62), while oxidation of HECMTP to HECSO showed characteristic emergence of a S=O stretch at 1055 cm -1 (Fig. 1G) (63).…”