Institutional Repository of Institute of Process Engineering, CAS (IPE-IR）
Not a member yet
40778 research outputs found
Sort by
Construction of Gemini composite based on TiO2 pillared montmorillonite for efficient oil-water separation
No full textOwing to the changeable components of oil-water system and the inflexible limitation of available materials during oil-water separation, the treatment of oily wastewater with wide pH, large discharge and high COD value remains a great challenge. In this study, a simple strategy was used to construct Gemini composite based on TiO2 pillared montmorillonite. The resultant montmorillonite-based Gemini composite (QATMt-x) exhibited high surface area (116.54 m2 g-1), surface potential (18.8 mV at pH2), good acid and alkali resistance, amphiphilicmultifunctional surface, and defective layered structure and, as a result, delivered high capability (ED >= 96 %) and long cyclic life for oil-water separation. More significantly, detailed mechanism studies reveal that the crucial reasons of oil-water separation on microemulsion and aqueous containing organic contaminant are demulsification through electron capture of the grafted chitosan, and adsorption by lipophilic saturated alkanes, titanium hydrates, (metal) hydroxyl and amine group, respectively. Hence, QATMt-x is particularly suitable for efficient demulsification in acidic media (pH 2) and for the adsorption of ecotoxic organic substances (e.g., perfluorooctanoic acid, methyl blue). In short, construction of Gemini surfactants based on low-cost inorganic carriers would offer new strategies in exploring amphipathic dual-functional layered structures for simultaneously efficient separation of multisystem oil-water scenarios
Refractory organics removal in PMS and H2O2/PMS oxidation system activated by biochar/nZVI/MoS2 composite: Synthesis, performance, mechanism and dosing methods
No full textA biochar composite loaded with nZVI particles and MoS2 nanosheets (nZVI/MoS2-BC) was prepared by calci-nation and hydrothermal methods, and could activate peroxymonosulfate (PMS) more efficiently to produce reactive oxygen species (ROSs) for refractory organics degradation. Due to the interaction between nZVI and MoS2, the reaction sites increased with nZVI dispersing more evenly and multitudinous MoS2 growing on the surface of biochar. PMS activated by nZVI/MoS2-BC produced SO4.-, .OH, O2.- and 1O2 to degrade pollutants. In addition, the increase of specific surface area and electrical conductivity accelerated the electron transfer from pollutions to metastable PMS to achieve pollutant degradation. The effects of catalyst dosage, PMS dosage, pH, inorganic anions and humic acid, and Cl- concentration in catalytic oxidation system were investigated. nZVI/ MoS2-BC was regenerated by calcination at 300 celcius after four cycles, and could still keep higher rhodamine B (Rh -B) removal (90.88%). Various pollutants removal efficiency could reach greater than 80% in nZVI/MoS2-BC catalytic oxidation system, such as Rh-B, methylene blue, chloramphenicol, tetracycline and bisphenol A. The combination of H2O2 and PMS could greatly reduce the cost, improve the pollutant removal and shorten the reaction time by changing the interval time and content ratio of oxidants addition. nZVI/MoS2-BC applied to the H2O2/PMS double oxidation system exhibited excellent removal capability of pollutants. The intermediates of Rh-B were analyzed and the degradation pathways were proposed in nZVI/MoS2-BC and H2O2/PMS double oxidation system
Rubber-Composite-Nanoparticle-Modified Epoxy Powder Coatings with Low Curing Temperature and High Toughness
No full textIn this study, a rubber-composite-nanoparticle-modified epoxy powder composite coating with low curing temperature and high toughness was successfully fabricated. The effects of N,N-dimethylhexadecylamine (DMA) carboxy-terminated nitrile rubber (CNBR) composite nanoparticles on the microstructure, curing behavior, and mechanical properties of epoxy-powder coating were systematically investigated. SEM and TEM analysis revealed a uniform dispersion of DMA-CNBR in the epoxy-powder coating, with average diameter of 100 nm. The curing temperature of the epoxy-composite coatings had reduced almost 19.1% with the addition of 1phr DMA-4CNBR into the coating. Impact strength tests confirmed that DMA-CNBR-modified epoxy-composite coatings showed significant improvements compared with the neat EP coating, which was potentially attributed to the nanoscale dispersion of DMA-CNBR particles in epoxy coatings and their role in triggering microcracks. Other mechanical properties, including adhesion and cupping values, were improved in the same manner. In addition, thermal and surface properties were also studied. The prepared epoxy composite powder coating with the combination of low curing temperature and high toughness broadened the application range of the epoxy coatings
Tailoring the Electronic Structure of Single Ag Atoms in Ag/WO3 for Efficient NO Reduction by CO in the Presence of O2
No full textDeveloping efficient catalysts for the selective catalytic reduction of NOx by CO (CO-SCR) is the key challenge for commercializing this technology. Ag-based catalysts with relatively low costs are promising but widely believed to be not efficient enough for this reaction. Here, we demonstrate that atomically dispersed Ag supported on ordered mesoporous WO3 (mWO3) can serve as a highly active catalyst for CO-SCR under O2-containing conditions. By altering the amount of the Ag precursor, the local environment of the Ag atom coordinated with the O atom can be tailored. Furthermore, at 250 degrees C and an O2/CO ratio of 2.5:1, 0.3Ag/m-WO3 (0.3 wt % Ag) with six-coordinated Ag-O exhibited much better catalytic performance than 5 Ag/m-WO3 (5 wt % Ag) with two coordinated Ag-O (e.g., 0.43 vs 0.02 molNO gAg -1 h-1 in the reaction rate) and previously reported Ag-based catalysts in the literature. The theoretical calculations confirm that the six-coordinated Ag atoms in 0.3Ag/m-WO3 possess a more positive oxidation state and a higher d-band center than the two-coordinated Ag atoms in 5Ag/m-WO3, promoting its bonding strength with co adsorption of the critical intermediates of N2O* and CO*. This work provides a feasible route for regulating the local environment of a Ag single atomic catalyst to enhance its catalytic property for CO-SCR
