查看更多>>摘要：The surface pore size and structure, as well as the hydrophilicity/hydrophobicity characterization of support layer are vital factors that affect the formation process of polyamide selective layer via interfacial polymerization. In this research, polysulfone support layers with similar pore structures but different hydrophilicity were prepared. Interfacial polymerization was conducted on the resulting support layers subsequently. As a single variable, how the support layer hydrophilicity affects morphology and performances of polyamide composite membrane were investigated. The results showed that: (1) if the surface pore sizes of support layers are similar, hydrophilic one could boost the diffusion rate of aqueous monomer into organic phase, and further affect the interfacial polymerization process; (2) hydrophilic support layer is not in favor of manufacturing polyamide composite membrane with good filtration performances and adhesion property; (3) hydrophilic support layer could not induce the poly amide formed within the support layer pore while the key factor is the interfacial position of aqueous phase and organic phase.
查看更多>>摘要：In this study, a novel poly (arylene ether ketone) with carboxyl groups (C-PAEK) was synthesized by adjusting the ratio of 4-carboxylphenyl hydmquinone (4C-PH) with bisphenol A (BPA). Fourier transform infrared spectroscopy (FTIR) and H-1 Proton Nuclear Magnetic Resonance (H-1 NMR) spectra demonstrated that C-PAEK polymer was successfully synthesized by the nucleophilic polycondensation reaction. A series of C-PAEK ultrafiltration membranes were prepared by nonsolvent-induced phase separation (NIPS) method. The effect of carboxyl content on the structure and properties of C-PAEK ultrafiltration membranes was studied by scanning electron microscope (SEM), thermogravimetric analysis, porosity, water contact angle (WCA), molecular weight cut-off (MWCO), ultrafiltration and antifouling experiments. C-PAEK membranes showed the typical asymmetric structure and finger-like channels. With the increase of carboxyl content in PAEK, the WCA of membranes decreased from 76.9 +/- 1.8 degrees (MO) to 57.3 +/- 1.6 degrees (M4). In addition, the weight loss temperature of 5% and the maximum weight loss rate temperature of C-PAEK are about 432 degrees C and 502 degrees C, respectively. Among the prepared membranes, the porosity (epsilon) of M2 with 10 wt% carboxyl groups content increased from 82.3 +/- 3.6% to 91.2 +/- 1.2%, but the average pore sizes (r(m)) of the membranes were similar. M2 showed the highest pure water flux (511.5 L/(m(2)h)), which was 1.7 times of M0. Rejection and flux recovery rate (FRR) of were 96.4 +/- 2.5% and 63.4%, respectively. Meanwhile, in the cyclic filtration experiment of C-PAEK membrane, with the increase of carboxyl groups, the FRR of both cycles was higher than that of the PAEK membrane. All results indicated that the membrane had high permeability, anti-fouling stability and durability. In short, the novel C-PAEK ultrafiltration membrane functionalized with 4C-PH demonstrated great potential for pollutant removal in the fields of pharmaceutical industry, food industry and bioengineering.
查看更多>>摘要：Peroxymonosulfate (PMS) based advanced oxidation process has been proved to be an efficient method for Antibiotic treatment. B, N co-doped carbon porous material was derived from metal-organic frameworks. B-NC catalysts showed excellent efficiency for removal of tetracycline hydrochloride. Nitrogen doping essentially changed the degradation pathway of tetracycline hydrochloride, while boron doping provided more active sites. through more defect sites, which is closely related to the adsorption and catalytic performance of the catalyst. The major active species of B-NC/PMS system was singlet oxygen (O-1(2)) through quenching experiments and electron paramagnetic resonance (EPR) studies. Electron transfer was another non-radical oxidation pathway of B-NC/PMS system. This provides a new idea for the selective oxidation of antibiotics by metal-free activated PMS.
查看更多>>摘要：Activated carbon clothes (ACCs) were modified by in situ deposition of silica nanoparticles (SiO2 NPs) to enhance the dielectric property of ACC surface and used as electrodes in the capacitive deionization (CDI) system. Four different concentrations of tetraethyl orthosilicate precursors were used as silica source and the effect of con-centration on the CDI performance was investigated. X-ray photoelectron spectroscopy (XPS) and Fourier transform infrared spectroscopy (FTIR) analysis revealed the presence of Si-O bonds on the ACC surface and Raman analysis confirmed the graphitic structure of the ACC was intact after grafting with SiO2 NPs. SiO2 NPs coated ACC electrodes revealed better desalination efficiency and average salt removal rate (ASRR) than pristine ACC. Specifically, ACC electrodes coated with 45 mM silica (SiO2-III) exhibited the highest specific capacitance of 97.4 +/- 0.1F/g, average desalination efficiency of 70 % with ASRR of 0.075 +/- 0.008 mg/cm(2)/min using 200 ppm NaCl. Moreover, CDI Ragone's plot verified the highest desalination rate was achieved with 45 mM SiO2 coated ACC electrodes. Furthermore, different salt concentrations and applied potentials upon desalination performances were also investigated. Moreover, post characterization of used pristine ACC and SiO2-III elec-trodes exhibited the sign of substantial electrode oxidation for pristine ACC but less on SiO2 NPs coated ACC electrodes. SiO2 NPs decorated ACC electrodes were not only enhanced localized electric field around dielectric coating of SiO2 NPs but also prevented the surface oxidation of the electrodes.
查看更多>>摘要：Herein, the development of a basic extractive distillation process for the separation of an ester/alcohol/water system, e.g., N-propyl acetate (PAC)/isopropanol (IPA)/H2O, is reported. To reduce the energy consumption of the process, mechanical vapor recompression technology was added to the basic extractive distillation process, and the heat exchange network was redesigned to further develop an enhanced distillation process. A hybrid pervaporation-distillation process was also developed to improve the high energy consumption of the solvent recovery tower used in the traditional extractive distillation process. Compared with the basic process, the total annual cost of the enhanced distillation process is 36.03% lower; thus, it is more economical. The global warming potential and acid potential of the hybrid pervaporation-distillation process are 500 kg CO2-ep and 0.75 kg SO2-ep, respectively, which indicates an improved environmental performance compared with that achieved by the traditional process. Although the economic advantage of the hybrid process compared with the enhanced distillation process is not clear when taking into account the high equipment cost, the hybrid process exhibits clear environmental performance advantages.
Peralta, DavidLavergne-Bril, Anna -CarolineBilly, EmmanuelColin, Jean-Francois...
6页
查看更多>>摘要：Owing to its specific properties, cobalt is a critical material for catalysis, stainless steel, and of course for Li-Ion batteries. Due to the intensive development of Li-ion batteries for transport applications (All-Electric and Plug-in Hybrid Electric Vehicles), the need for cobalt will dramatically increase. Unfortunately, resource is scarce and more than half of the cobalt production is presently concentrated in only one country (Democratic Republic of the Congo). Recycling and reusing cobalt from used batteries in a closed-loop process in order to limit cobalt imports becomes mandatory. In this paper, we propose a disruptive and very efficient route to selectively precipitate cobalt from a spent batteries solution, which consists in using imidazole linkers. The resulting hybrid material can be directly used as a precursor to produce a new cobalt-cathode based material.
查看更多>>摘要：The mass transfer performance of CO2 is an index for the design of CO2 capture equipment. In this study, the mass transfer characteristics of CO2 in the blade unit of a tridimensional rotational flow sieve tray (TRST) were investigated using a CO2-NaOH system. The rotational and perforated flow modes were separated experimentally, and the rotational flow ratio of the gas phase at the outlets was controlled such that the flow characteristics of the blade unit were similar to those of the TRST. The effects of the gas-phase artificial rotational flow ratio (R-ctrl), gas-phase F-factor (F-s), and liquid spray density (L-w) on the overall volumetric mass transfer coefficients of the rotational and perforated flows ([K(G)a(v)](rot), [K(G)a(v)](per)), as well as the overall volumetric mass transfer coefficient of the total process [K(G)a(v)](tot)), were investigated. The results showed that under the experimental conditions, [K(G)a(v)](rot) increased with R-ctrl and L-w. F-s did not significantly affect [K(G)a(v)](per), whereas [K(G)a(v)](per) increased with L-w, reaching a maximum value of 0.00194 kmol/(m(3)center dot s center dot kPa). The mass transfer processes of the two flow modes are complementary. When R-ctrl is 0.5, [K(G)a(v)](tot) is optimal at 0.0023 kmol/(m(3)center dot s center dot kPa). This study lays a theoretical foundation for the optimal design of TRSTs.
查看更多>>摘要：Anthracene (ANT) and carbazole (CAR) are highly value-added compounds in chemical industry. They are always mixed in preliminary processing products of high temperature coal tar and need to be separated and purified. In this study, ionic liquids (ILs) were used to separate ANT and CAR. [C3PY], [PM2IM] and [PMPIP] cations along with 7 classes of anions were screened by the conductor-like screening model for real solvents (COSMO-RS). [PMPIP][TFAc] (ILa) and [PMPIP][Ac] (ILb) were selected and synthesized. The structures of ILs were studied by sigma-profile at the micro-level to analysis the hydrogen bonds formed between anion of ILs and H-N of CAR. The ternary phase diagrams of ANT-CAR-ILs were plotted to analysis the separation efficiency. Two ILs were used as extractant to separate ANT and CAR. The separation results showed that the synthesized ILs were the highly efficient solvents. The purity of refined ANT separated by ILb was improved to 97.87 wt%, with a yield of 80.04 wt%. The separation mechanism of ANT and CAR was further discussed.
查看更多>>摘要：Of large amounts of catalysts that have been developed to date for high catalytic activity and durability, perovskite oxides have appealed the attention due to their inherent performance as well as structural flexibility. Especially, the aurivillius perovskites could be a fantastic "pollutants oxidizer". Therefore, we designed a novel catalyst, LCBT-2 (LaCoO3:Bi4Ti3O12 = 1:2, mole ratio), composed by ultrathin aurivillius perovskite Bi(4)Ti(3)O(12 )nanosheets and typical perovskite LaCoO3 particles. This new type of composite catalyst appeared exceptional catalytic activity and high stability for tetracycline (TC) degradation. The activity of TC degradation by LCBT-2 reached 87.8% and the activity could maintain 78.4% after 4 cycles, proving the high durability of LCBT-2. A proposed mechanism for the synergistic effects between Bi4Ti3O12 and LaCoO3 was analyzed by active species trapping experiment and electron paramagnetic resonance (EPR). Moreover, the possible pathways of TC degradation were proposed according to the results of high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS). This study aims at the application of coupled perovskite oxides as photocatalysts for TC degradation and reveals the reason of synergistic effects between the two part of perovskite oxides (Z-scheme heterojunction interface) by experiments and in-depth mechanistic analysis.
查看更多>>摘要：Ultrafiltration was demonstrated to be an effective and efficient method to treat algae-laden water. However, the presence of compounds such as surfactants can act as a stimulus for algae outbreak and change the characteristics of algae cells and derived organics. Therefore, it is necessary to investigate the filtration and separation performance of ultrafiltration during the treatment of algae-laden water in the presence of anionic surfactants (the most widely used surfactant type). In this study, sodium dodecyl sulfate (SDS) and sodium dodecyl benzene sulfonate (LAS) were employed respectively to simulate the presence of a low concentration of an anionic surfactant in eutrophicated water. It was found that surfactants present in natural waters could enhance the hydrophilicity of the algae interface and the stability of the algae-laden water system with mitigated algae aggregation. During the initial filtration process, membrane fouling was aggravated related to the more serious pore blocking induced by the present SDS or LAS; however, during the next stage, membrane fouling was alleviated due to the formation of a looser cake layer in the presence of SDS or LAS. The pore blocking at the earlier stage contributes more to the decrease of total flux when surfactants are involved. Furthermore, the disinfection byproduct formation potential was reduced with SDS or LAS mainly due to the degradation of free available chlorine by the surfactants. While the concentration of algal toxins was ascended in the ultrafiltration effluent, which indicates that the separation performance was highly impacted by the presence of anionic surfactant.
NSTL
Elsevier