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The modified membrane GO-Ag/PVDF was fabricated using co-polymer F127 and nanocomposite GO-Ag as functional additives via non-solvent induced phase separation (NIPS) method for natural organic matter (NOM) resistance. Due to the introduction of co-polymer F127 and nanocomposite GO-Ag, resultant membranes exhibited excellent hydrophilicity and permeability. Meanwhile, the modified membrane surface showed better fouling resistance to natural organic matter (NOM) and bacteria compared with pristine membrane. In summary, the membrane MF1825 under the optional additive combination possessed the better performance with pure water flux of 82 L·m −2 ·h −1 and the contact angle of 62° comparing the membrane MF1800 with pure water flux of 14 L·m −2 ·h −1 and the contact angle of 80°. In addition, the membrane MF1825 had the improved fouling resistance order to NOM models: BSA > SA > HA, which indicated a potential application in natural organic water treatment. [ABSTRACT FROM AUTHOR]

In this study, highly dispersed spherical lead (Pb) nanoparticles were prepared from Pb contained solders of waste printed circuit boards (WPCBs) by combining vacuum evaporation and forced flow inert gas condensation. With a relatively high vapor pressure, Pb could be easily separated from waste Pb/Sn solders by vacuum evaporation, while Sn still remained in the residues. Simultaneously, Pb nanoparticles were prepared by the dynamic inert gas condensation. Agglomeration and size inhomogeneity phenomena were eliminated to the maximum extent by sharp quenching using forced flow inert gas and optimizing operation parameters like dynamic nitrogen gas pressure, heating and condensation temperature and condensation distance away from the heater. Highly dispersed spherical Pb nanoparticles were prepared under the optimized conditions of 1223 K heating temperature, 1000 Pa dynamic nitrogen gas pressure, 413 K condensation temperature and 60 cm condensation distance away from the heater. The separation efficiency of Pb from waste solders could reach to higher than 98.2 wt% with the product purity of more than 98 wt% and the size distribution ranging from 20 to 100 nm. This work provides the theoretic foundation for recycling Pb with high added values from waste Pb/Sn solders or other Pb contained solid wastes. [ABSTRACT FROM AUTHOR]