Nanjing Tech University

About: Nanjing Tech University is a education organization based out in Nanjing, China. It is known for research contribution in the topics: Catalysis & Membrane. The organization has 21827 authors who have published 21794 publications receiving 364050 citations. The organization is also known as: Nangongda & Nánjīng Gōngyè Dàxúe.

Biodiesel Production by Esterification of Oleic Acid over Brønsted Acidic Ionic Liquid Supported onto Fe-Incorporated SBA-15

Abstract: The esterification of oleic acid with short-chain alcohols using Bronsted acidic ionic liquid supported onto Fe-incorporated SBA-15 (Fe-SBA-15) was studied to develop a green method for biodiesel production. This catalyst was prepared by immobilization of Bronsted acidic ionic liquid 1-(propyl-3-sulfonate)-3-(3-trimethoxysilylpropyl) imidazolium hydrogen sulfate ([SO3H-PIm-CPMS][HSO4]) onto Fe-SBA-15 (IL/Fe-SBA-15). The structure of the catalyst was characterized by XRD, N2 adsorption–desorption measurement, FT-IR and TEM. The results demonstrated that Fe was incorporated into the framework of SBA-15, bringing Lewis acidic site. After the ionic liquid was successfully immobilized onto the surface of Fe-SBA-15, the structure of the catalyst remained intact. This catalyst displayed relatively high catalytic activity in esterification of oleic acid with short-chain alcohols because of the synergistic effect of Lewis and Bronsted acidic sites. Under the optimum reaction conditions (reaction temperature 363 K,...

Pd nanoparticles encapsulated into mesoporous ionic copolymer: Efficient and recyclable catalyst for the oxidation of benzyl alcohol with O2 balloon in water

Abstract: A series of functional cross-linked mesoporous poly(ionic liquid)s (MPILs) were prepared through the free radical copolymerization of divinylbenzene (DVB) and imidazolium salts based ionic liquids tethered with different groups (−COOH, C 4 H 9 , −CN and −NH 2 ). These MPILs were applied as supports to prepare immobilized palladium (Pd) nanoparticles (NPs) through ion exchanging with sodium tetrachloropalladate(II) (Na 2 PdCl 4 ) and successive reduction by sodium borohydride (NaBH 4 ). Highly uniform and narrow dispersed Pd NPs attained on the carboxyl modified MPIL with large surface area and high ionic density. The obtained materials acted as an efficient and stable recycling heterogeneous catalyst for the atmospheric pressure oxidation of benzyl alcohol to benzaldehyde by using O 2 as the oxidant and water as the sole solvent at low temperature (90 °C). The special ionic framework with −COOH group plays a major role in the formation and stabilization of ultrafine Pd NPs. This work indicates that controlling the textural properties of ionic copolymers serves as a facile and efficient way to fabricate immobilized stable metal NPs.

Swelling-induced mesoporous block copolymer membranes with intrinsically active surfaces for size-selective separation

Abstract: Block copolymers (BCPs) are receiving growing interest in the preparation of advanced membranes with regular pores due to their capability to form highly ordered, mesoscopic structures via microphase separation. We report on the fabrication of composite membranes with mesoporous amphiphilic BCPs as the size-selective layer and a macroporous membrane as the supporting layer by coating BCPs onto the supporting membrane. Mesopores were generated in the BCP layer by a selective swelling-induced pore-formation process. The composite membranes showed high pore regularity, strong mechanical robustness, and a separating property that can be tuned simply by changing the swelling time. Furthermore, the polyelectrolyte-natured blocks were exclusively relocated on the pore surface of the BCP layer during the swelling process, rendering an intrinsically active surface on the membrane. As a result, the hydrophilicity and fouling resistance of the membranes were significantly enhanced, and the membranes possessed a reversible pH-sensitive water flux. The membranes were used to separate nanoparticles of similar sizes and it was observed that the membrane subjected to 24 h of swelling was able to discriminate 10 nm gold particles from a mixture containing 2 nm gold particles with ∼100% yield, demonstrating its superior size selectivity.