Natural clay minerals such as sepiolite (Sep) and montmorillonite (Mt) are used as low-cost adsorbents to remove tetracycline (TC) in water, and the spent adsorbents saturated with TC are regenerated under microwave (MW) irradiation. The adsorption and regeneration properties of Sep and Mt are compared. The possible adsorption and MW regeneration mechanisms are proposed. The results show that 11.25 mg.g(-1) and 20.74 mg.g(-1) adsorption capacities of Sep and Mt are obtained, respectively, within 120.0 min at 298 K. Mt has higher adsorption capacity, faster adsorption rate and shorter adsorption time for TC than that of Sep. The adsorption processes using Sep and Mt are well-fitted to pseudo-second-order kinetics and Langmuir models. The two adsorption reactions are spontaneous and endothermic, with increased randomness at solid- liquid interfaces . Moreover, 89.76 % and 114.45 % maximum regeneration ratios are obtained for Sep and Mt, respectively. Mt exhibits superior regeneration performance than Sep. After eight adsorption-regeneration cycles, the two adsorbents can maintain excellent adsorption and regeneration performance. This work provides new perspectives on the adsorption technology using natural clay minerals to remove antibiotics and the MW regeneration technology to regenerate spent natural clay minerals saturated with organic pollutants in organic wastewater treatment.

In this study, novel dual wave-absorbing ZnFe2O4/CNTs nanoparticles were successfully fabricated using a microwave hydrothermal method and applied for enhanced microwave-induced catalytic degradation of bisphenol A (BPA) in aqueous solution. The effects of various process parameters, including Fe3+ concentration (mass ratio of ZnFe2O4 to CNTs), MW irradiation time, MW power, initial BPA concentration, and catalyst dose on the degradation process were thoroughly assessed. The results indicate that ZnFe2O4/CNTs nanoparticles effectively utilize MW energy to generate more hot spots and exhibit superior MW catalytic activity at a 1.0:10.0 mass ratio (ZnFe2O4:CNTs), due to the synergistic effect between ZnFe2O4 nanoparticles and CNTs under MW irradiation. Additionally, hydroxyl radicals (& sdot;OH) play a major role in the degradation process, while superoxide radicals (& sdot;O2- ) and holes (h+) play relatively minor roles. Potential intermediates and degradation pathways in the ZnFe2O4/CNTs/MW system have also been identified. Thus, the integrated ZnFe2O4/CNTs/MW technology shows great promise for treating environmental endocrine disruptors (EEDs) in water and wastewater.

烯烃的烷氧羰基化反应是目前生产酯类化合物最重要的均相催化反应,烷氧羰基化反应催化剂的开发与改性备受关注.此外,均相烷氧羰基化催化剂的回收和无"CO"的羰基化过程也一直是烷氧羰基化反应的研究热点.综述近年来烷氧羰基化反应催化剂的研究进展,归纳双膦配体上不同活性基团对催化剂性能的影响,总结均相烷氧羰基化催化剂的固载化和液-液两相体系两种催化剂的回收方法,介绍甲酸、甲醛和CO2三种羰基源替代物实现烯烃高效羰基化的反应方法.

以开源软件OpenFOAM为平台,开发出适于跨/超临界射流的模型,以研究跨/超临界条件下的喷雾混合特性.模型基于真实流体状态方程和扩展的压力隐式分割算法(PISO),并结合雷诺平均(RANS)湍流模型,对跨/超临界条件下的液氮射流进行模拟,重点分析射流的伪沸腾特性.研究结果表明:在跨临界射流伪沸腾发生之前,射流表面形成显著的密度分层可抑制湍流扩散和混合层发展;在超临界射流下,混合层内的密度梯度较小,这导致射流能够更快地达到自相似状态.

ABSTRACT A laboratory scale biological purification system that removes hydrogen sulfide (H2S) in waste gas at low temperature condition from -1 to 10 °C was investigated for a continuous operation of 82 days. Good performance of the biological purification system was obtained, and the highest elimination capacity was 1214 g·m-3 ·h-1 at the inlet load of 1919 g·m-3 ·h-1. In the experimental period, pH of packing was maintained in the neutral range. The removal efficiency of H2S was not affected by the accumulation of sulfate and the consumption of nitrogen. The performance of the biological purification system was maintained in a high level and exhibited a strong long-term potential H2S removal capability in this 82 day.

In the last decade, the scientific community has witnessed explosive growth in research on the direct carbamoylation of C–H and X–H (X = N, O) bonds with formamides via cross-dehydrogenative coupling reactions. This novel approach is an effective means of preparing a variety of carboxamide, carbamate as well as urea derivatives, which are prevalent in medicinal chemistry and natural product synthesis. This review elaborates the most important advances and developments in the field, with an emphasis on the reaction patterns and mechanisms.

The paper describes a new kind of ionogel with both good mechanical strength and high conductivity synthesized by confining the ionic liquid (IL) 1-butyl-3-methylimidazolium bis(trifluoromethane sulfonyl)imide ([Bmim][NTf2]) within an organic–inorganic hybrid host. The organic–inorganic host network was synthesized by the reaction of methyltrimethoxysilane (MTMS), tetraethoxysilane (TEOS), and methyl methacrylate (MMA) in the presence of a coupling agent, offering the good mechanical strength and rapid shape recovery of the final products. The silane coupling agent 3-methacryloxypropyltrimethoxysilane (KH-570) plays an important role in improving the mechanical strength of the inorganic–organic hybrid, because it covalently connected the organic component MMA and the inorganic component SiO2. Both the thermal stability and mechanical strength of the ionogel significantly increased by the addition of IL. The immobilization of [Bmim][NTf2] within the ionogel provided the final ionogel with an ionic conductivity as high as ca. 0.04 S cm−1 at 50 °C. Moreover, the hybrid ionogel can be modified with organosilica-modified carbon dots within the network to yield a transparent and flexible ionogel with strong excitation-dependent emission between 400 and 800 nm. The approach is, therefore, a blueprint for the construction of next-generation multifunctional ionogels.

Several Cu/ZnO/Al2O3 catalysts with high Cu and ZnO contents were used to study the influence of solvent polarity on the dehydrogenation and dehydration of isoborneol. The employment of a polar solvent enhanced the activity for the main dehydrogenation reaction, while the use of a non-polar solvent favored the dehydration side-reaction. Different techniques were employed to characterize the fresh, treated, and spent catalysts. X-ray powder diffraction (XRD) showed that the copper was in metallic form and zinc in oxide form, transmission electron microscope (TEM) showed differences in catalyst morphology that depended on the polarity of the solvent used, N2O titration gave the Cu active site density, and temperature-programmed desorption of NH3 (NH3-TPD) provided the acidity of the materials. The characterization results indicated that in non-polar solvents the copper nanoparticles were sintered and this may have been due to the enhanced activity of adventitious water in those solvents or simply because of interactions between the solvents and the copper and zinc oxide components. The sintering resulted in a decrease in the number of active sites and an increase in acidic sites, which enhanced the undesired dehydration reaction. Based on the results of inductively coupled plasma (ICP) and TEM, a model of the catalyst was proposed to illustrate the effect of solvent polarity on the dehydrogenation of isoborneol.

In this study, a series of strongly luminescent organosilica-modified carbon dots were successfully synthesized in a scalable manner via hydrothermal treatment of citric acid and glucose in the presence of a silane coupling agent. Organosilica as a stable component coupled with the surface of carbons leads to the formation of gel-like materials. The obtained carbon dots can be homogeneously dispersed in various polar solvents such as water or ethanol to produce an optical solution. Importantly, the abundance of organosilica groups on the surface makes carbon dots ideally suited for use as fantastic carbon precursors for the construction of porous carbon materials. The carbons resulting from the pyrolysis of carbon dots consist of interconnected carbon nanoparticles with surface areas of up to 725 m(2) g(-1) and nitrogen content of 4.84%. Such carbons show potential application as supercapacitor electrodes with high specific capacitance of 185.4 F g(-1) at 0.5 A g(-1) and 176.3 F g(-1) at 1 A g(-1) in 6 mol L-1 KOH. Considered a relatively green and simplistic process, this current synthetic protocol would be a promising avenue to access functional carbon materials with tunable porosity, heteroatom doping and specific morphology.

以多孔酚醛树脂XAD761为载体,采用表面官能团修饰的方法制备了固载铑膦配合物的催化剂XAD761/P/Rh,实现了均相氢甲酰化反应催化剂的固载化.采用红外光谱、等温氮气吸附和X射线光电子能谱等方法对所制得的催化剂进行表征,证实了二苯基氧磷结构配位中心的存在及铑膦配合物催化中心在酚醛树脂载体表面的形成.经过电感耦合等离子-原子发射光谱测得磷和铑的负载量分别为1.39％和0.40％,催化剂中磷铑比为11.分别以1-辛烯和苯乙烯为底物考察了催化剂的催化性能,结果表明,在一定条件下XAD761/P/Rh在催化活性方面和三苯基膦作配体时的均相催化剂效果相当,1-辛烯和苯乙烯的成醛收率分别可以达到77.9％和99.6％.所制备的催化剂经过简单的过滤分离即可实现循环使用.

Anodic electro-catalysis oxidation is a highly effective way to solve the pollution problem of antibiotics in wastewater and receiving water bodies. In this study, for the first time, molybdenum trioxide/Nano-graphite (MoO3/Nano-G) composites are synthesized as anodic catalysts by a surfactant-assisted solvothermal method followed by low-temperature calcination. The effects of the proportion of MoO3 to Nano-G (10, 30 and 50%) on the properties of composites are investigated through structural characterizations and electrochemical measurements. Results indicate that MoO3(30)/Nano-G electrode displays the electro-catalysis degradation efficiency of 99.9% towards ceftazidime, which is much higher than those of Nano-G (46.7%) and dimensionally stable anode (69.2%). The degradation mechanism for ceftazidime is studied by investigating the yields and kinds of active species. Results show that all of the OH, O2− and H2O2 are responsible for the electro-catalytic degradation process, and the produced OH radicals are the major active species for ceftazidime degradation. The synergistic effects between MoO3 and Nano-G greatly contribute to the activation of H2O molecules to produce OH, meanwhile the special sesame cake-like structure facilitates to the exposure of contaminants to OH on active sites to enhance the degradation efficiency. These results suggest that MoO3/Nano-G electrodes can be considered as the promising catalysts for treating bio-refractory organic wastewater.

Hybrid organic-inorganic (HOI) based on f-PMMA-SiO2 materials were synthesized by in situ polymerization of methyl methacrylate (MMA) monomer and tetraethoxysilane (TEOS) precursor with the assistance of 3-trimethoxysilyi-propyl-methacrylate (KH-570) as coupling agent. Dye-ionic liquids and the ionic liquid 1-butyl-3-methylimidazolium bis(trifluoromethane sulfonyl)imide [Bmim][NTf2] and 1-butyl-3-methylimidazolium methyl orange [Bmiml[MO] were used as guests for the synthesis of pH-responsive functional poly(methylmethacrylate) (f-PMMA-SiO2) ionogels. The pendent groups of KH-570 allow its linkage to both the silica and MMA, leading to a uniform composite. Optical inspection of the ionogels suggests that the materials are transparent and homogeneous without macroscopic defects. The hybrid ionogels possess a high ionic conductivity of 10(-4) S cm(-1) at 373 K. The bulky gel shows tunable mechanical stability with compressive strength up to 4 MPa that is markedly dependent on the f-PMMA and the ionic liquids incorporation. In particular, color change is clearly observed when the ionogels exposed to proton-containing solution. Moreover, HOI ionogels exhibit significantly enhanced structural integrity in both proton-containing aqueous and organic solution. The resulting material is thus an interesting prototype of flexible, stable and transparent ionogels combining the mechanical properties of the hybrid with the functionality of the ionic liquids. (C) 2017 Elsevier B.V. All rights reserved.

A process used reactive distillation with isophorone as a cosolvent to produce cyclohexanol was proposed. Feeding the reactants cyclohexene and water with the cosolvent isophorone into the reac-tive distillation column(RDC), then using two rectifying columns(PDC1 and PDC2) to purify and separate the bottom product, a high-purity product of cyclohexanol can be obtained and the purity of isophorone can be recycle back to the RDC. The whole process was simulated with the NRTL thermo-dynamic equation, then it was simulated and calculated by the Aspen Plus software, a high-purity cy-clohexanol (99.9%, mole fraction) and a recyclable isophorone can be obtained finally, the heat du-ties of the system were 0.9823 kW. On the basis of the calculation, we discussed the operating condi-tions including the molar ratio of isophorone and cyclohexene, the molar ratio of water and cyclohex-ene, the pressure of column, which have effects on the cyclohexene conversion and heat duty of the system to optimize the process, and the cyclohexene conversion of the proposed process is compared with other process.

The performance of carbon rod (CR), titanium sheet (TS), stainless steel woven mesh (SSM) and copper sheet (CS) cathode materials are investigated in microbial fuel cells (MFCs) for simultaneous electricity generation and Cu(II) reduction, in multiple batch cycle operations. After 12 cycles, the MFC with CR exhibits 55% reduction in the maximum power density and 76% increase in Cu(II) removal. In contrast, the TS and SSM cathodes at cycle 12 show maximum power densities of 1.7 (TS) and 3.4 (SSM) times, and Cu(II) removal of 1.2 (TS) and 1.3 (SSM) times higher than those observed during the first cycle. Diffusional resistance in the TS and SSM cathodes is found to appreciably decrease over time due to the copper deposition. In contrast to CR, TS and SSM, the cathode made with CS is heavily corroded in the first cycle, exhibiting significant reduction in both the maximum power density and Cu(II) removal at cycle 2, after which the performance stabilizes. These results demonstrate that the initial deposition of copper on the cathodes of MFCs is crucial for efficient and continuous Cu(II) reduction and electricity generation over prolonged time. This effect is closely associated with the nature of the cathode material. Among the materials examined, the SSM is the most effective and inexpensive cathode for practical use in MFCs.

A packed-bed reactive and extractive distillation column was proposed to recover polyvinyl alcohol by-product methyl acetate. The azeotrope of methyl acetate and methanol from a polyvinyl alcohol plant was used as experimental material. In the reactive and extractive distillation column, methanol was transformed to methyl acetate over a cation-exchange resin. The simulation for this process was carried out by means of the RADFRAC equilibrium stage model in Aspen Plus. The equilibrium-stage model can describe the reactive and extractive distillation column, but heat loss of the laboratory-scale distillation column should be taken into account in the simulation at a low reflux ratio. The effects of several operation parameters, such as the stage number of reaction section, and stage number of non-reaction section, the reflux ratio, the volume ratio of the extractive solvent to the feed mixture, and the feed location on the performance of the reactive and extractive distillation column were investigated. According to the simulation results, a novel process for methyl acetate recovery was developed, and the methyl acetate purity in the distillate and the methanol conversion can reach higher than 99% and 94%, respectively. (C) 2015 Elsevier B.V. All rights reserved.

A mini trapezoidal solar pond with surface 2.4 m x 2.4 m and bottom 1.0 m x 1.0 m is constructed. Thermal performance of the trapezoidal solar pond is numerically simulated by a one-dimension model base on the experimental data. The simulation builds a thermal and salt diffusion model, a modified bottom reflection and radiation transmission model, and a detailed heat dissipation model considering the heat loss from the surface, the wall and the soil layer. It shows a good agreement between the experimental data and the simulation. In the simulation the temperature of the trapezoidal pool is overall higher than that in the rectangular pool, the maximum difference is about 5 degrees C, and the trapezoidal structure contributes to reduce the heat loss of heat storage layer. It has great significance for the thermal performance of the solar pond to reduce the turbidity of upper convective zone and non-convective zone. The stability of the interface between non-convective zone and lower convective zone is better than that between upper convective zone and non-convective zone. (C) 2015 Elsevier Ltd. All rights reserved.

Cottonseed oleic acid were taken as raw materials , bentonite and lithium carbonate as the catalyst and cocatalyst , reaction at 240℃for 4 h .The influence of the structure and composite of dif-ferent bentonites on the catalytic performance was investigated in the dimerization of the cottonseed oil acid.The results showed that the difference of the specific surface area and the porosity of different bentonites were comparatively large .But they were not the leading factor that influenced their catalytic properties.The layer spacing of the bentonite crystal and its surfacial acidity had an important effect on its yield .In the experiment , the maximum yield of the dimer acid is 70 .26%, the minimum is 43.58%.The reason may be larger interlayer spacing can provide more adequate reaction space which is conducive to the generation of large volumes of dimeric molecules and help the product spread from the layered structure .In addition the catalytic properties was increased with the high molar ratio of the Lewis acid to the Br?nsted acid .The reason may be the L acid site plays a key role in the unsaturated fatty acid polymerization.The Al /Si molar ratio of three kinds of bentonite range from 0.216 to 0.239, so the difference is small .It has a small effect on the reaction .

The solubility of d-camphor-10-sulfonic acid (D-CSA, CAS No. 3144-16-9) in seven solvents (ethyl acetate, methyl acetate, n-butyl acetate, isopropyl acetate, glacial acetic acid, acetic anhydride and propionic acid) was measured under atmospheric pressure. The solubility data were correlated by the modified Apelblat equation, the λh equation, the Wilson model and the UNIQUAC model, respectively. And the thermodynamic parameters of D-CSA, molar dissolution enthalpy and entropy, were determined by the Van’t Hoff equation to explain its dissolving behavior in each solvent.

Microbial fuel cells (MFCs) using either Cr(VI) (MFCsCr) or Cu(II) (MFCsCu) as a final electron acceptor, are stacked to self-drive microbial electrolysis cells (MECs) using Cd(II) (MECsCd) as an electron acceptor for simultaneous reduction of Cr(VI) in MFCsCr, Cu(II) in MFCsCu and Cd(II) in MECsCd with no external energy consumption. Titanium sheet (TS) and carbon rod (CR) as the cathodes of MECsCd are assessed for efficient system performance. MFCsCr and MFCsCu in series is superior to the parallel configuration, and higher Cd(II) reduction along with simultaneous Cr(VI) and Cu(II) reduction supports TS function as a good cathode material. Conversely, CR can not entirely proceed Cd(II) reduction in MECsCd despite of more Cr(VI) and Cu(II) reduction in the same serial configuration than either system alone. While a decrease in cathode volume in both MFCsCr and MFCsCu with serial connection benefits to reduction of Cr(VI) in MFCsCr and Cu(II) in MFCsCu, Cd(II) reduction in MECsCd is substantially enhanced under a decrease in cathode volume in individual MFCsCr and serially connected with volume-unchanged MFCsCu. This study demonstrates simultaneous Cr(VI), Cu(II) and Cd(II) recovery from MFCsCr-MFCsCu-MECsCd self-driven system is feasible, and TS as the cathodes of MECsCd is critical for efficient system performance.

The free subsidence features of turbidity brine under different salinities,working mediums and temperatures were discussed by laboratory experiments.A new physical treatment method of turbidity reduction was applied to solar pond by introducing porous adsorbent,and the turbidity restraint effects of four types of porous mediums were investigated.Two mini-solar ponds with area of 2.4 m×2.4 m and depth of 1.2 m were built,and one of them was filled with porous medium at the bottom.A mixed regression model of solar radiation transmittance was put forward based on the nonlinear fitting of the experimental data.The experimental results show that the turbidity removal ratio of salt water is about 10% higher than that of brine.When the salinity increases from 0.2% to 20%,the turbidity removal ratio of salt water is reduced by 8%.The free subsidence speed of dust particles is enhanced and the turbidity removal ratio can be increased by 3%-1 3% after different porous mediums are filled in salt-gradient solar pond.Porous mediums can effectively reduce the water turbidity and increase the solar radiation transmittance in the solar pond.