查看更多>>摘要：n-Butanol is an advanced next-generation drop-in biofuel, which can be produced by anaerobic acetone-butanol-ethanol (ABE) fermentation using biomass derived carbohydrates as substate by Clostridia sp. Nevertheless, even though there are plenty of breakthroughs for continuous improving the competitiveness of biological n-butanol production towards the petrol-chemical ones, a series technical barrier still limited the commercialization of ABE industry. As one of the major bottlenecks, the complex constitution of solvent product with extremely low concentrations always resulted in the energy-intensive downstream separation of the ABE production from fermentation broth, which further challenged the economic viability of the whole n-butanol process. To overcome the obstacle, in recent years, great effort has been taken to seek for an energy-saving and cost-effective technique for ABE separation from fermentation broth. This review aims to highlight the mechanisms of the arisen alternative n-butanol separation techniques and covered along with the limitations and advantages of these techniques. A comprehensive discussion of the current emerged trends in multi-stages separation integration processes are also made for the prospective separation techniques involved in n-butanol production.
查看更多>>摘要：To realize the harmless treatment and resource recycling of oily shale cuttings, the most important step is to desorb the oil phase from the pores of the cuttings. The desorption treatment must overcome the capillary force and viscous resistance inside the pores. This paper discusses a cyclone oil desorption technology. The particles of the oily shale cuttings in the swirl field generated by the cyclone will have high-speed self-rotation, thus providing sufficient centrifugal forces that separate the phase oil from the pores. The critical speed of such self-rotation for the desorption of oil phase in pores of particles was analyzed using mechanical formula, and the distribution of particle self-rotation speed in the cyclone was calculated and simulated. We collected shale cutting samples from the Sichuan shale gas field in China. Experiments were conducted to observe the changes in the porosity and oil content of the cuttings before and after cyclone desorption treatment. The results show that the particle self-rotation in the cyclone can effectively achieve the oil phase desorption from the particle pores. For the shale cuttings in the experiments, when the particle self-rotation speed is faster than the critical self-rotation speed of 507rad/s, the oil phase in the particle pores can be desorbed. When the inlet flow rate is between 55m~3/h - 95m~3/h, the particle self-rotation speed is faster than the required critical self-rotation speed. As the inlet flow rate increases, the particle self-rotation speed in the cyclone also increases, which generates better desorption effects.
查看更多>>摘要：The authors regret, Acknowledgements: This study was also supported by the Tamarisk Outstanding Young Talents Program of Lanzhou University of Technology.
查看更多>>摘要：PIM-1 mixed matrix membranes (MMMs) were fabricated with polyhedral oligomeric silsesquioxane (POSS) and graphene oxide (GO) functionalized with POSS (GO-POSS), and tested for CO2/N2 (single gas) and CO2/CH4 (1:1, v:v gas mixture). The CO2 permeability of the best performing fresh MMM (containing 0.05 wt% GO-POSS) was ～ 12000 Barrer, which is 69% higher than that of the neat PIM-l membrane, with about the same selectivity (CO2/CH4 selectivity ～12 and CO2/N2 selectivity ～ 20). In both cases, the gas separation data surpass the 2008 Robeson upper bound. In addition to the initial CO2 permeability enhancement, the use of GO-POSS is an efficient strategy to slow down physical aging. The MMM at a filler loading of 0.75 wt% showed less than half of the reduction in CO2 permeability than the neat PIM-1 membrane 160 days after preparation (26% for the MMM vs 58% for the purely polymeric one).
查看更多>>摘要：Hydrogen sulfide is a highly flammable, acutely toxic, and extremely hazardous gas that must be captured and removed from a number of important gaseous and liquid streams. This long-standing challenge of capturing H2S has seen the rise of different materials used in different types of technologies over the years. Some of the well-known examples are alkanolamines used as absorbents and metal oxides used as adsorbents. This work presents an exhaustive review of the latest developments and emerging materials in this field, including ionic liquids, deep eutectic solvents, zeolites, carbon-based materials, metal organic frameworks, polymeric membranes, biological methods, advanced oxidation processes, etc. In addition to a detailed discussion of the state of the art, this review also provides a general technology map and identifies opportunities and challenges to guide future work.
查看更多>>摘要：Based on two topologicals distinct MOFs, the core-shell bimetallic MIL-101/ZIF-67x (M/Zx) were successfully prepared to activate the self-decomposition of peroxymonosulfate (PMS) for 2-chlorophenol (2-cp) degradation. The M/Zx not only inherited the merits of single-metal MOFs such as high surface area and pore volume, but also exhibited superior catalytic performance. In the M/Zx/PMS system, 90% of the 2-cp (100 mg/L) was removed within 10 min with a reaction rate of 0.241 min~(-1). This observation was attributed to the synergistic catalysis of cobalt and iron active sites in M/Zx, which greatly promoted the Co~(2+)/Co~(3+) redox cycle, thereby enhancing the catalytic performance. Further investigation found that both radical and non-radical pathway jointly promote the degradation of 2-cp, and the singlet oxygen (~1O2) mediated non-radical pathway serve a predominant role. Meanwhile, SO4~(·-) and ·OH also accelerated this process. The possible degradation pathway was proposed by identifying the intermediates of 2-cp degradation. This work provides some new ideas for the design of multi-metal MOFs for environmental remediation.
查看更多>>摘要：Polymer-based hemodialyzers have been widely used to treat patients suffered from end stage renal disease clinically. Polyethersulfone (PES) is seen as one of the most important hemodialysis membrane materials. Numerous strategies have been done to increase the hemocompatibility of PES, but molecular chain modification of PES has been seldomly reported. In this work, a hydrophilic ionic liquid (IL) grafted PES (PES-g-IL) was used to prepare the hollow fiber membranes (HFMs). The structure and properties, including hemocompatibility, hemodialysis performance as well as the cytotoxicity of PES-g-IL HFMs were investigated systematically. It was found that PES-g-IL HFMs had higher porosity, lower protein adsorption, less platelet adhesion and longer clotting time than PES HFMs, indicating the enhanced hemocompatibility. Besides, both the toxins removal and BSA rejection of PES-g-IL HFMs were significantly higher than those of PES HFMs. Particularly, the middle molecule uremic toxin (lysozyme) clearance of PES-g-IL HFMs was twice higher than that of PES HFMs. At the same time, the BSA rejection of PES-g-IL HFMs achieved as high as 98%. Moreover, PES-g-IL showed negligible cytotoxicity. It is considered that the grafting of IL changed the microstructure and improved the hydrophilicity of PES-g-IL membranes, leading to the enhanced hemocompatibility, hemodialysis performance and cytocompatibility.
查看更多>>摘要：Ion imprinting is an extension of molecular imprinting in which target ions are used as templates to prepare ion-imprinted polymers (IIPs) with specific ion recognition. IIPs have applications in electrochemical sensors, solid-phase extraction, preconcentration, membrane separation, and water treatment due to their advantages of simple preparation, fixed hole size, stable structure, good environmental stability, strong regeneration ability, and selectivity to template ions. Here, based on the latest progress of this new technology, we have carried out a systematic review, summarized 1) the principle, basic components and polymerization methods of metal ion imprinted polymers; 2) the cross-application status of metal ion imprinting technology and other technologies; 3) influence of experimental parameters on properties of metal ion-imprinted polymers; 4) development prospects of metal ion imprinted polymers; 5) recent progress in the synthesis and application of major group metal elements, transition metal elements and rare earth metal elements. Finally, prospects and future research are discussed to address the urgent need to develop metal imprinted polymers for metal ion recovery.
查看更多>>摘要：Solid oxide electrolysis cell(SOEC) can efficiently convert CO2 to CO using renewable energy sources, which can alleviate the threatening impact of excessive CO2 emissions on the human life and environment. Moreover, it also realizes chemical storage of available electricity to ease the energy consumption crisis. Designing cathode materials with abundant active sites and high-efficiency electrochemical catalytic activity toward CO2 reduction is crucial for realizing practical applications of SOEC. Herein, construction of a composite heterostructure of alkaline-earth metal compounds and Sr2Fe_(1.5)Mo_(0.5)O_(6-δ) (SFM) double perovskite oxides by alkaline-earth metal infiltration was proposed. This strategy enriched the reactive sites and led to the expansion of the triple-phase boundary, thereby effectively improving the electrochemical performance of SOEC. The experimental results show that the infiltration of alkaline-earth metal led to significant increase in the surface active sites, improvement in the adsorption and activation process of CO2, and promotion of the formation of activated carbonate intermediates. The current density on the CaC03-infiltrated SFM cathode reached 1.723 A cm~(-2), while the current density on the SFM cathode could only reach 1.117 A cm~(-2) at 1.8 V and 800 °C. The alkaline-earth metal infiltration strategy not only improves the electrochemical performance, but also maintains excellent stability after 100 h of operation at high temperature and 12 redox cycles. All these results indicate that the construction of heterostructure through alkaline-earth metal infiltration provides an effectual strategy for improving the electrochemical performance of SOEC.
查看更多>>摘要：The authors regret <the changes to the affiliation for the authors to read: School of Chemistry and Chemical Engineering, Guangdong Engineering Technology Research Center of Advanced Insulating Coating, South China University of Technology, Guangzhou 510640, P.R. China>.
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