The chemical composition of pectin production wastewater and its toxicity during biological treatment were investigated. Samples of wastewater from different steps of a pectin production wastewater biological treatmen...The chemical composition of pectin production wastewater and its toxicity during biological treatment were investigated. Samples of wastewater from different steps of a pectin production wastewater biological treatment plant were investigated including the influent of the treatment （1）, after denitrification tank （2）, after anaerobic treatment （3） and final effuent （4）. The conventional physicochemical characteristics of samples did not indicate wastewater toxicity. However, toxicity assessments carried out on Vibrio fischeri and Scenedesmus subspicatus indicated low EC50 values. The fractionation of the samples using an XAD resin showed that the toxicity was associated with the organic matter. Wastewater apparent molecular mass distributions were 14.3, 25.0, 24.4 and 29.6 kDa for samples 1-4, respectively. Finally, characteristics of the sample by pyrolisis-gas chromatography-mass spectrometry （Py-CG-MS） demonstrated its polyphenolic nature and a 23% increase in the levels of such compounds after the first biological treatment step.展开更多
基金supported by a grant from the National Council for Development and Research (CN-Pq/Brazil)
文摘The chemical composition of pectin production wastewater and its toxicity during biological treatment were investigated. Samples of wastewater from different steps of a pectin production wastewater biological treatment plant were investigated including the influent of the treatment （1）, after denitrification tank （2）, after anaerobic treatment （3） and final effuent （4）. The conventional physicochemical characteristics of samples did not indicate wastewater toxicity. However, toxicity assessments carried out on Vibrio fischeri and Scenedesmus subspicatus indicated low EC50 values. The fractionation of the samples using an XAD resin showed that the toxicity was associated with the organic matter. Wastewater apparent molecular mass distributions were 14.3, 25.0, 24.4 and 29.6 kDa for samples 1-4, respectively. Finally, characteristics of the sample by pyrolisis-gas chromatography-mass spectrometry （Py-CG-MS） demonstrated its polyphenolic nature and a 23% increase in the levels of such compounds after the first biological treatment step.
