This study focuses on determining the toxicological risks of urban waste from the city of Uvira, discharged into Lake Tanganyika, on the surrounding population. Volatile organic compounds were measured in a variety of...This study focuses on determining the toxicological risks of urban waste from the city of Uvira, discharged into Lake Tanganyika, on the surrounding population. Volatile organic compounds were measured in a variety of solid waste matrices, including inorganic micropollutants in wastewater and fish. The concentrations of Hg and Pb in the lake were found to be 1.21 and 1.42 μg/L respectively and between 0.83 to 18.36 μg/L of Hg and 8.25 to 670 μg/L of Pb, at the collector outlet. The presence of trace metallic elements, such as Cr, Co, Ni, Cu, Zn, As, Sb, Hg and Pb, were detected at high concentrations compared to the WHO standard. An ecotoxicology experiment herein on wastewater samples showed lethal pollutant concentrations of the order of 0.0055 mL/mL which killed at least 50% of fish (LC50), confirming the toxicity of the wastewater. These potentially harmful effluents also contain volatile organic compounds originating in high concentration from the pharmaceutical discharges of the general Uvira hospital, in particular: toluene, ethylbenzene, m-xylene/p-xylene, o-xylene and chloroform in higher concentrations compared to the norm. Other components such as benzene, bromodichloroethane and 1,1-dichloroethane were found to be present, but at a concentration below 0.05 ppb. A variety of trace organics can be suspected to be present as well.展开更多
Aromatic amines are crucial in pharmaceuticals,but their synthesis is challenging due to unfavorable reaction equilibria and the use of costly,environmentally unfriendly methods.This study presents a membrane extracti...Aromatic amines are crucial in pharmaceuticals,but their synthesis is challenging due to unfavorable reaction equilibria and the use of costly,environmentally unfriendly methods.This study presents a membrane extraction(ME)process for in situ product removal(ISPR)of aromatic amines.Using a supported liquid membrane(SLM),α-methylbenzylamine(MBA)and 1-methyl-3-phenylpropylamine(MPPA)were separated from isopropyl amine(IPA).Conductor-like Screening Model for Real Solvents(COSMO-RS)was employed to screen over 200 organic mixtures,identifying twelve mixtures based on trioctylphosphine oxide(TOPO),lidocaine,and menthol as solvent candidates,due to their hydrophobicity.These mixtures were analysed for critical solvent properties including density,viscosity,hydrophobicity,and H-bonding interactions.ME tests showed TOPO-thymol had the highest solvent residual and selectivity.Moreover,TOPO-thymol demonstrated solute fluxes of 9.0±3.0 g/(m^(2)h)for MBA,16.5±5.4 g/(m^(2)h)for MPPA,and 0.7±0.3 g/(m^(2)h)for IPA,with selectivity values of 12.4±0.8 for MBA/IPA and 22.8±1.4 for MPPA/IPA.Compared to undecane,which had lower selectivity values of 6.9±0.8 for MBA/IPA and 10.1±1.3 for MPPA/IPA,TOPO-thymol showed superior selectivity,indicating its promise as an extractant for ME applications.展开更多
文摘This study focuses on determining the toxicological risks of urban waste from the city of Uvira, discharged into Lake Tanganyika, on the surrounding population. Volatile organic compounds were measured in a variety of solid waste matrices, including inorganic micropollutants in wastewater and fish. The concentrations of Hg and Pb in the lake were found to be 1.21 and 1.42 μg/L respectively and between 0.83 to 18.36 μg/L of Hg and 8.25 to 670 μg/L of Pb, at the collector outlet. The presence of trace metallic elements, such as Cr, Co, Ni, Cu, Zn, As, Sb, Hg and Pb, were detected at high concentrations compared to the WHO standard. An ecotoxicology experiment herein on wastewater samples showed lethal pollutant concentrations of the order of 0.0055 mL/mL which killed at least 50% of fish (LC50), confirming the toxicity of the wastewater. These potentially harmful effluents also contain volatile organic compounds originating in high concentration from the pharmaceutical discharges of the general Uvira hospital, in particular: toluene, ethylbenzene, m-xylene/p-xylene, o-xylene and chloroform in higher concentrations compared to the norm. Other components such as benzene, bromodichloroethane and 1,1-dichloroethane were found to be present, but at a concentration below 0.05 ppb. A variety of trace organics can be suspected to be present as well.
基金the support provided by the Flemish Strategic Basic Research Program under the Catalisti clusterFlanders Innovation & Entrepreneurship, through the EASiCHEM project (contracts HBC.2018.0484 and K200522 N)+1 种基金partially conducted within the framework of the CICECO-Aveiro Institute of Materials project (UIDB/50011/ 2020, UIDP/50011/2020, and LA/P/0006/2020)funding from national sources through FCT/MEC (PIDDAC)
文摘Aromatic amines are crucial in pharmaceuticals,but their synthesis is challenging due to unfavorable reaction equilibria and the use of costly,environmentally unfriendly methods.This study presents a membrane extraction(ME)process for in situ product removal(ISPR)of aromatic amines.Using a supported liquid membrane(SLM),α-methylbenzylamine(MBA)and 1-methyl-3-phenylpropylamine(MPPA)were separated from isopropyl amine(IPA).Conductor-like Screening Model for Real Solvents(COSMO-RS)was employed to screen over 200 organic mixtures,identifying twelve mixtures based on trioctylphosphine oxide(TOPO),lidocaine,and menthol as solvent candidates,due to their hydrophobicity.These mixtures were analysed for critical solvent properties including density,viscosity,hydrophobicity,and H-bonding interactions.ME tests showed TOPO-thymol had the highest solvent residual and selectivity.Moreover,TOPO-thymol demonstrated solute fluxes of 9.0±3.0 g/(m^(2)h)for MBA,16.5±5.4 g/(m^(2)h)for MPPA,and 0.7±0.3 g/(m^(2)h)for IPA,with selectivity values of 12.4±0.8 for MBA/IPA and 22.8±1.4 for MPPA/IPA.Compared to undecane,which had lower selectivity values of 6.9±0.8 for MBA/IPA and 10.1±1.3 for MPPA/IPA,TOPO-thymol showed superior selectivity,indicating its promise as an extractant for ME applications.
