无定形硅铝载体的酸性对费托蜡加氢裂化反应中柴油选择性的影响

利用逐梯度铵交换处理的方法合成了三个织构性质相似、酸性不同的无定形硅铝载体,并通过XRD、N₂吸附-脱附、NH₃-TPD、Py-FTIR和NMR等手段对载体的物化性质进行了研究。经等体积浸渍负载贵金属Pt,制成加氢裂化催化剂,以费托蜡加氢裂化生产柴油为探针反应,研究了无定形硅铝载体的酸性与柴油选择性之间的构效关系。结果表明,柴油选择性主要与载体的B酸性质有关,受L酸的影响很小;催化剂载体的强B酸含量与柴油选择性成相反关系,载体强B酸的含量越低,柴油选择性越高;催化剂Pt/B-1具有相对最高的柴油选择性,在反应压力7.0 MPa,H₂/wax（volume ratio）=1 000：1,LHSV=1.0 h^-1,温度为370℃的条件下,C₂₂₊转化率为62.52%时,对柴油的选择性达87.12%,具有比文献报道及商业化无定形硅铝载体ASA制备的催化剂Pt/ASA相对更高的活性和柴油选择性。     

热处理及反应介质对Cu-Zn-Al催化剂的结构及CO加氢催化性能的影响

催化剂的形成和使用环境对催化剂的结构和性能会产生重要的影响。本文采用完全液相法,以PEG-400和液体石蜡分别作为热处理介质制备Cu-Zn-Al催化剂,用X射线粉末衍射、H2程序升温还原、N2吸附、X射线光电子能谱对其进行表征,考察热处理介质对催化剂结构的影响;以相应的热处理介质作为浆态床反应介质,考察介质对CO加氢催化反应性能的影响。结果表明,PEG-400作为热处理介质有助于提高催化剂的比表面积、ZnO的分散度和表面铜含量,催化剂中存在难还原的Cu ,有利于形成Cu -Cu0之间的协同作用;在反应过程中,PEG-400作为反应介质可以抑制铜晶粒的长大,有利于乙醇的生成及C5烃选择性的提高,但催化剂的结构和表面组成会发生较大的变化。     

The study of compatibility of polyethylene and polypropylene by using irradiated polyethylene wax

The modification of the compatibility between polyethylene (PE) and polypropylene (PP) by using irradiated PE wax (PE wax) is the purpose of this study. In this part, polymer blends based on various ratios of PE and PP were blended with 2.5% PE wax in all the blend ratios to determine the optimum ratio of the blend to be compatabilized. The influence of PE wax as a compatibilizing agent for PE and PP blend was investigated through the measurements of thermal, mechanical and morphological properties. The PP/PE blends modified by this method showed higher mechanical properties than those of the unmodified blends. Also, stress and strain of the modified blend having ratio (60/40) PP/PE blend recorded the maximum mechanical behavior. Scanning electron microscopy (SEM) micrographs of modified blends showed an indication of strong interfacial adhesion and a smooth continuous surface in which giving a support to the effect of irradiated PE wax as a tool for improving the compatibility.     

Wax formation in oil pipelines: A critical review

The gelling of waxy crudes and the deposition of wax on the inner walls of subsea crude oil pipelines present a costly problem in the production and transportation of oil. The timely removal of deposited wax is required to address the reduction in flow rate that it causes, as well as to avoid the eventual loss of a pipeline in the event that it becomes completely clogged. In order to understand this problem and address it, significant research has been done on the mechanisms governing wax deposition in pipelines in order to model the process. Furthermore, methods of inhibiting the formation of wax on pipeline walls and of removing accumulated wax have been studied to find the most efficient and cost-effective means of maintaining pipelines prone to wax deposition. This paper seeks to review the current state of research into these areas, highlighting what is so far understood about the mechanisms guiding this wax deposition, and how this knowledge can be applied to modelling and providing solutions to this problem.     

石蜡微胶囊的制备

针对太阳能利用以及一些蓄热场合,通过示差扫描量热法（DSC）选取了合适的石蜡,以脲醛树脂为囊壁,采用原位聚合法制备了石蜡一脲醛树脂微胶囊,拟将此微胶囊添加到上述应用场合的传热流体中,提高传热流体的热容。实验结果表明,乳化剂OP更适合于熔点60℃石蜡微胶囊的制备。     

蛋白质的反射散射光度研究

研究了微晶石蜡吸萃蛋白质-偶氮胂Ⅲ-镝(Ⅲ)复合物的条件,并设计了固相反射散射分光光度直接测定石蜡相中蛋白质的方法。所拟定的方法有较好的选择性,可以用于实际生物样品中蛋白质含量的测定。     

Determination of the upper limits, benchmarks, and critical properties for gas separations using stabilized room temperature ionic liquid membranes (SILMs) for the purpose of guiding future research

The literature reports that supported ionic liquid membranes (SILMs) outperform standard polymers for the separations of CO₂/N₂ and CO₂/CH₄, even under continuous flow mixed gas conditions. Before the expenditure of more resources to develop new room temperature ionic liquids (RTILs) and SILMs, it is time to consider what benchmarks for SILM performance exist and if upper limits could be projected based on the physical chemistry of RTILs. At this juncture, we should ask if the current research efforts are properly focused based on the successes and failures in the literature. We summarize literature data, along with adding new data, on the SILM permeabilities and selectivities for the following gas pairs: CO₂/N₂, CO₂/CH₄, O₂/N₂, ethylene/ethane, propylene/propane, 1-butene/butane, and 1,3-butadiene/butane. The analysis predicts a maximum CO₂-permeability for SILMs and an upper bound for permeability selectivity vs. CO₂-permeability with respect to the CO₂/N₂ and CO₂/CH₄ separations. Also summarized are the representative successes and failures for improving the separation performance of SILMs via functionalization and facilitated transport in the context of the CO₂/N₂, CO₂/CH₄, and olefin/paraffin separations. In the context of the CO₂-separations, the analysis recommends a number of future research foci including research into SILMs cast from RTILs with smaller molar volumes. In the context of olefin/paraffin separations, the preliminary data is encouraging when considering the use of facilitated transport via silver carriers. Since RTIL-solvent/solvent interactions dominate in terminating the overall SILM performance, past attempts at enhancing solute/solvent interactions via the addition of functional groups to the RTILs have not produced SILMs with better separation performance compared to the unfunctionalized RTILs. Future research into functionalized RTILs needs to consider the changes to the dominant solvent/solvent interactions and not just the solute/solvent interactions.     

高温气相色谱和高温气相色谱-质谱法对费托合成蜡的分离和鉴定

费托合成蜡是费托合成反应中的重要产物之一。采用高温气相色谱与冷柱头进样相结合的方式,建立了一种分离分析费托合成蜡的气相色谱方法。该方法无需对费托合成蜡进行预处理,使用氦气为载气,选用更长的高温色谱柱,具有平稳的色谱基线,对费托合成蜡中正构烷烃和其他未知组分有很好的分离效果,能够洗脱费托合成蜡中碳数大于C₉₀的重组分。用高温气相色谱-质谱法对费托合成蜡馏分进行定性分析,其组分有烷烃、烯烃和含氧化合物。该方法对了解费托合成蜡组分的详细信息和费托合成工艺的开发有重要意义。     

Influence of chlorinated paraffin/titanium additives on burning and radiance performances of Magnesium/Teflon/Viton(MTV) foil-type composition

The influence of chlorinated paraffin/titanium (C₂₄H₂₉Cl₂₁/Ti) additives on burning and radiance performances of Magnesium/Teflon/Viton™ (MTV) foil-type was investigated via a high-speed camera, high-temperature differential thermobalance, far-infrared thermal imager and Fourier Transform Infrared (FTIR) remote-sensing spectrometer. We found that the burning temperature, radiance brightness, radiance area and radiance intensity after addition of C₂₄H₂₉Cl₂₁/Ti are improved by 124–196 °C (8–13%), 300–475 W·m⁻²·sr⁻¹ (12–19%), 943–1422 mm² (67–101%) and 3.17–4.99 W·sr⁻¹ (88–138%), respectively, and are maximized at the addition ratio of 10%. The substances formed by adding C₂₄H₂₉Cl₂₁/Ti could improve the middle and far infrared radiation.