基于促进传递机理的烯烃/烷烃分离用固体聚合物电解质膜的研究进展

对膜法烯烃/烷烃分离技术的现状进行了总结,论述了膜法促进传递分离烯烃/烷烃的机理、研究进展及存在的问题.分析了固体聚合物电解质膜对烯烃/烷烃分离性能的影响因素,探讨了固体聚合物电解质中高分子材料和烯烃载体对膜性能的影响,阐述了烯烃载体Ag+的中毒及再生过程和烯烃渗透的时间依赖性.     

光还原对固体聚合物电解质膜结构及丙烯/丙烷分离性能的影响

用单侧表面溶液交换法制备PEI/Pebax2533/AgNO3及PEI/Pebax2533/AgBF4复合气体分离膜,研究了光还原对复合膜结构及气体渗透性能的影响.对PEI/Pebax2533/AgBF4 复合膜,光还原使活性载体Ag+浓度降低,对烯烃的促进传递作用减弱,导致丙烯渗透通量以及丙烯/丙烷的选择性明显下降.但光还原对PEI/Pebax2533/AgNO3复合膜的丙烯/丙烷分离性能无显著影响.复合膜中的Ag+被光还原为Ag0,使复合气体分离膜表面变为棕色.还原后的银颗粒含量随着交换溶液银盐浓度的增加而增加,证明交换溶液银盐的浓度明显支配着复合膜中的Ag+负载含量,从而影响膜的分离性能.     

脱卤化氢合成氢氟烯烃催化剂的研究进展

氢氟烯烃具有较低的温室效应潜值,被认为是氢氟烷烃的理想替代品.卤代含氟烷烃气相催化脱卤化氢是目前合成氢氟烯烃较为理想的方法,相应的催化剂技术已成为其核心.综述了用于脱卤化氢反应的各类催化剂,以及影响催化剂性能的因素,并对催化剂的研究前景进行了展望.     

多产异构烷烃的催化裂化工艺技术开发与工业应用

从催化裂化反应机理出发，提出了两个反应区的概念，设计了具有两个反应区的串联提升管反应器并形成相应的工程技术，在此基础上进行了中小型探索试验和工业试验。1.4 Mt/a多产异构烷烃的催化裂化装置试验标定结果表明：与现有的催化裂化工艺相比，该工艺不仅优化了产物分布，干气和油浆产率分别下降了0.41%和0.99%，液体收率增加了1.17%，而且所生产的汽油烯烃含量下降约14.1%，异构烷烃增加约为12.9%，硫的质量分数ω(s)下降26.5%,诱导期增加,汽油的RON下降而MON增加,总的抗爆指数略有下降。     

金属-有机骨架在烷烃／烯烃分离中节约能源

塑料行业需要大量的纯的乙烯和丙烯来生产聚（乙烯）和聚（丙烯）。但这些化合物必须从原油在500—600℃派生出来的烃类混合物中分离。烷烃／烯烃混合物（如丙烷／丙烯）的分离是通过将混合物冷却至-100℃，随后进行低温精馏实现的，此过程需要巨大的能量输入。为了有效节省能源，     

65万吨／年煤基甲醇制烯烃分离工艺选择

论文研究了65万吨／年煤基甲醇制烯烃分离工艺工艺原理，通过AspenPlus流程模拟软件模拟分析UOP精馏分离工艺和PROA吸收分离工艺两种分离工艺的工艺流程，对比评估，结果表明PROA吸收分离工艺为65万吨／年煤基甲醇制烯烃更优工艺。     

ZIF-8膜分离丙烯/丙烷的研究进展

丙烯/丙烷的高效分离是获取高纯度丙烯的关键步骤.膜分离因其效率高、能耗低、操作简便等优势有望取代高能耗的精馏过程.沸石咪唑酯骨架(ZIFs)具有结构规整、孔径可调、热稳定性和化学稳定性高等特征,在膜分离领域具有较大的应用潜力.ZIF-8可以对尺寸极为相近的丙烯和丙烷进行有效筛分,是目前丙烯/丙烷分离膜领域的研究焦点.以ZIF-8膜分离丙烯/丙烷的研究进展为核心,重点阐述了ZIF-8膜的合成方法、分离性能、稳定性及柔韧性等备受关注的问题,为ZIF-8膜在烯烃/烷烃分离领域的工业化应用提供借鉴与指导.     

界面层极化诱导法制备低晶态MOF超薄膜

正烯烃/烷烃分离为石化行业最重要,也是最耗能的分离过程之一,目前主要采用低温精馏进行分离.膜分离作为新型高效节能分离技术,有望在该方面发挥重要作用.金属-有机骨架材料(MOFs)具有优异的孔道结构和化学特性,在膜分离领域展现出巨大的前景.而超薄膜有望克服分离膜的选择性与渗透性的制约难题,获得整体性能优异的分离膜.但是,现有MOF超     

陶瓷膜可望替代蒸汽裂解使乙烷转化为乙烯

美国能源部Argonne国家实验室的研究团队开发了利用膜技术使烷烃生成烯烃的新技术，这种技术可减少被废弃的能源用量及排放的污染物，从而提高了效率和产率。这一技术已申请美国专利U．S．329，791B2。     

超临界烯烃聚合的研究进展——Ⅲ.相行为

以超临界烯烃聚合为背景,在介绍超临界特征的基础上系统阐述了聚烯烃在超临界烷烃流体中的相行为。概括了聚烯烃内部结构包括种类、分子量和支化度,及超临界烷烃流体性质和第三组分的加入等对聚烯烃溶解度的影响。同时,比较了超临界烷烃流体对聚烯烃的溶胀特性及相应的熔点变化。     

Superb storage and energy saving separation of hydrocarbon gases in boron nitride nanosheets via a mechanochemical process

Light hydrocarbon olefin and paraffin gas mixtures are produced during natural gas or petrochemical processing. The petrochemical industry separates hydrocarbon gas mixtures by using an energy-intensive cryogenic distillation process, which accounts for 15% of global energy consumption [1]. The development of a new energy-saving separation process is needed to reduce the energy consumption. In this research, we develop a green and low energy mechanochemical separation process in which boron nitride (BN) powders were ball milled at room temperature in the atmosphere of an alkyne or olefin and paraffin mixture gas. BN selectively adsorbs a much greater quantity of alkyne and olefin gas over paraffin gases, and thus the paraffin gas is purified after the ball milling process. The adsorbed olefin gas can be recovered from the BN via a low-temperature heating process. The mechanochemical process produces extremely high uptake capacities of alkyne and olefin gases in the BN (708 cm³/g for acetylene (C₂H₂) and 1048 cm³/g for ethylene (C₂H₄)) respectively. To the best of our knowledge, assisted by ball milling, BN nanosheets have achieved the highest uptake capacities for alkyne/olefin gases, which are superior to all other materials reported so far. Chemical analysis reveals that large amounts of olefin gases were quasi-chemically adsorbed on the in-situ formed BN nanosheets via C–N bond formation, whereas small amount of paraffin gases was physically adsorbed on BN nanoparticles. This scalable mechanochemical process has great potential as an industrial separation method and can realize substantial energy savings.     

Alternatives to Cryogenic Distillation: Advanced Porous Materials in Adsorptive Light Olefin/Paraffin Separations

As primary feedstocks in the petrochemical industry, light olefins such as ethylene and propylene are mainly obtained from steam cracking of naphtha and short chain alkanes (ethane and propane). Due to their similar physical properties, the separations of olefins and paraffins—pivotal processes to meet the olefin purity requirement of downstream processing—are typically performed by highly energy‐intensive cryogenic distillation at low temperatures and high pressures. To reduce the energy input and save costs, adsorptive olefin/paraffin separations have been proposed as promising techniques to complement or even replace cryogenic distillation, and growing efforts have been devoted to developing advanced adsorbents to fulfill this challenging task. In this Review, a holistic view of olefin/paraffin separations is first provided by summarizing how different processes have been established to leverage the differences between olefins and paraffins for effective separations. Subsequently, recent advances in the development of porous materials for adsorptive olefin/paraffin separations are highlighted with an emphasis on different separation mechanisms. Last, a perspective on possible directions to push the limit of the research in this field is presented.     

Remarkably Selective Propylene–Propane Separation Using a Copper Scorpionate

Propylene is a crucial building block to produce many industrial-scale chemicals including polypropylene. The separation of propylene from propane to reach the high-purity levels needed for downstream applications is a difficult task due to the close similarities in their physical properties. The olefin/paraffin separation including that involving propylene mainly relies on highly energy-intensive distillation processes and accounts for nearly 0.3% of the global energy consumption. The utility of a copper complex supported by a fluorinated bis(pyrazolyl)borate is demonstrated to accomplish the separation of propylene from propane repeatedly, under mild conditions with high selectivity. Complete characterization of a rare, copper(I) propylene complex is also reported including the molecular structure.     

热致相分离法制备防水透气膜

使用大豆油和液体石蜡作为混合稀释剂,通过热致相分离法(TIPS)制备了聚丙烯(PP)防水透气微孔膜。采用扫描电子显微镜(SEM)、水通量测试、气体通量测试等手段对膜的形貌和性能进行了表征。研究结果表明,向豆油里添加液体石蜡,能有效增大膜孔隙率,同时膜的防水透气性能也有很大提高。     

Membrane reactor microstructure for polymer grade olefin production and hydrogen cogeneration

The current communication describes research work on effective membrane reactor nanostructures and nanoreaction-nanoseparation technology for polymer grade olefin production via catalytic paraffin dehydrogenation reactions. Emphasis is given in systems of permreactors and permeators to perform the described reactive and separative operations. We elaborate on new membrane microstructure designs for paraffin dehydrogenations including the design of experiments, operation, and best parameter selection and optimization of such systems. The described processes are of current significance in the area of new microreactor design and operation including hydrocarbon processing and conversion to valuable fuels and chemicals such as hydrogen, olefins, and polyolefins. These improved results are because of the unique design characteristics of the examined microreactor systems to perform accurate multiphase and heterogeneous functions into one unit operation. A number of membrane reactor configurations were made and tested on stream for the catalytic propane dehydrogenation reaction to propylene with successful results. Some of the results are discussed below which show the better performance of nanostructured membrane reactors for the specific dehydrogenation.     

Exploiting charge-transfer complexation for selective measurement of gas-phase olefins with nanoparticle-coated chemiresistors

Charge-transfer-mediated olefin-selective sensing by use of chemiresistors (CR) coated with composite films of n-octanethiolate-monolayer-protected gold nanoparticles (C8-MPN) and each of several square-planar PtCl2(olefin)(pyridine) coordination complexes is described. Where the gas-phase olefin analyte differs from that initially coordinated to Pt, olefin substitution occurs and is accompanied by a persistent shift in the composite film resistance. Commensurate changes in film mass are also observed with a similarly coated thickness shear mode resonator. Regeneration is possible by exposure to the initially complexed olefin gas or vapor. If the olefin analyte is the same as that initially coordinated to Pt, then a reversible charge-transfer interaction occurs that is accompanied by a decrease in film resistance (increase in film mass), which recovers spontaneously after removal of the olefin from the atmosphere above the sensor. This behavior differs from that of MPN-coated CRs lacking such Pt complexes, which invariably yield resistance increases upon exposure to nonpolar vapors. Red shifts in the UV-vis absorbance spectra of the PtCl2(olefin)(pyridine) complexes in solution upon addition of free olefin support the hypothesis that Pt-olefin coordination in the composite films creates temporary low-resistance pathways that compete effectively with the concurrent increase in tunneling resistance associated with swelling-induced separation of C8-MPN cores. Structurally analogous non-olefins produce only increases in film resistance. Selective measurement of styrene, ethylene, 1-octene, and 1,3-butadiene is illustrated. Olefin detection limits are reduced as much as 23 000-fold by inclusion of the corresponding Pt complex in the CR interface film. Composite films suffer a gradual loss of selectivity from decomposition of the Pt-olefin complex, apparently facilitated by a Au-Pt charge transfer.     

新型无机二维材料在气体分离膜领域的研究进展

气体膜分离技术是过滤与分离工业的重要技术之一, 相比于传统分离技术更加高效、节能、环保。新型无机二维材料在分离膜领域的应用, 有望同时实现高选择性和高渗透率, 突破商业聚合物膜渗透率和选择性相互制约的瓶颈, 极大地促进高性能分离膜的发展。本文简述了膜的气体分离机制, 综述了石墨烯基、过渡金属硫族化物(TMDs)和二维过渡金属碳化物/氮化物(MXene)等新型无机二维材料近年来在气体分离膜领域的研究进展, 包括其设计、制造和应用, 探讨了不同材料分离膜的特点、面临的挑战和发展前景。此外, 本文对其他新兴二维材料——层状双氢氧化物(LDHs)、六方氮化硼(h-BN)、云母纳米片等的分离膜研究也进行了概述。最后, 对新型无机二维材料在气体分离膜领域的研究方向及面临的挑战作出了评价。     

新型多孔材料在惰性气体Xe/Kr分离中的应用

惰性气体氙与氪的分离在大气放射性核素监测、惰性气体工业制备和乏燃料处理等领域中均有重要应用。常规的方法是利用低温精馏将氙与氪从大气中分离,需要耗费大量能源,成本高。因此,作为替代方法在常温下通过多孔材料高效吸附分离氙与氪具有重要意义。近年来发展的以金属有机框架材料、多孔有机分子笼材料等为代表的新型多孔材料在惰性气体氙与氪的分离中展现出了优异的性能与良好的应用前景。系统地综述了新型多孔材料在Xe/Kr分离中的研究进展,从计算模拟在Xe/Kr分离研究中的应用、高浓度氙/氪分离研究与极低浓度Xe/Kr分离研究3个方面进行论述与总结,最后对未来研究趋势进行了总结与展望。