CO2在低碳烷烃催化转化中的综合利用

对近年来CO2用于甲烷重整,甲烷氧化偶联,低碳烷烃脱氢制烯烃,脱氢芳构化等方面的工作进行了评述.指出开发高活性催化剂,有效活化碳氢键与碳氧键,增加催化剂的稳定性是未来工业应用中的核心问题.     

长链正构烷烃催化脱氢制取直链单烯烃的研究进展

较为详细的综述了长链正构烷烃催化脱氢制取长链烯烃的基本原理（包括热力学和动力学）和该反应中催化剂的研究进展，据此提出了改进此反应的两种工艺方法。     

碳五烷烃裂解制低碳烯烃反应性能的分析

考察了碳五烷烃的热裂解和催化裂解反应性能,发现正戊烷和异戊烷的裂解反应产物存在差异;进一步分析了正戊烷和异戊烷的裂解反应机理,以及裂解生成低碳烯烃和甲烷的区别。结果表明,在热裂解条件下,正戊烷的（乙烯+丙烯）选择性高于异戊烷,异戊烷的丁烯和甲烷选择性高于正戊烷;650℃时,正戊烷和异戊烷的热裂解产品中（乙烯+丙烯）、丁烯、甲烷的选择性分别为37.48%、7.23%、6.75%和19.57%、25.16%、9.36%。而在催化裂解条件下,异戊烷的（乙烯+丙烯）、丁烯、甲烷选择性均高于正戊烷;650℃时,正戊烷和异戊烷的催化裂解产品中（乙烯+丙烯）、丁烯、甲烷的选择性分别为37.16%、9.11%、7.80%和47.70%、14.45%、13.79%。此外,发现在高温裂解条件下异构烷烃比正构烷烃容易裂解生成丁烯和甲烷。     

重油催化裂解制低碳烯烃工艺的研究进展

近年来,随着石油工业的快速发展,对低碳烯烃,尤其是丙烯、乙烯的需求越来越大。开发以石油为原料,通过催化裂解的工艺,生产低碳烯烃逐渐成为当今社会生产的趋势。本文结合重油催化裂解制低碳烯烃工艺,对催化裂解催化剂以及我国的重油催化裂解制低碳烯烃技术进行了简要的探究和阐述。     

C4烷烃裂解制低碳烯烃应用研究进展

本文详细介绍了C4烷烃蒸汽裂解和催化裂解技术;与蒸汽裂解技术相比,催化裂解具备降耗增产的同时降低对原料油的苛刻、减少对设备的腐蚀等优点,C4烷烃催化裂解技术在国内外已取得了一些实验室的研究成果,并出现以KBR公司的ACO技术为例的成熟的催化剂体系和催化裂解工艺。     

碳四烷烃催化裂解制低碳烯烃的研究进展

论述了碳四烷烃催化裂解制低碳烯烃的催化剂体系、影响因素及催化裂解方式。该催化剂体系包括硅铝酸盐及锆硫酸盐,氧化铝与碱金属或碱土金属的混合物,负载型催化剂等3种类型。其中分子筛(晶体硅铝酸盐)及其改性催化剂是研究开发的主要方向。除操作条件外,稀释剂、引发和抑制剂和裂解反应方式对催化裂解反应均有影响。催化裂解反应机理与催化剂的种类和反应条件相关。对于酸性分子筛催化剂有2种比较公认的机理:正碳离子机理,自由基与正碳离子机理两种形式。研究表明碳四烷烃,特别是正丁烷催化裂解制低碳烯烃具有良好的低碳烯烃收率,收率可达50%以上。     

硼基材料催化低碳烷烃氧化脱氢制烯烃研究进展

以氮化硼为代表的硼基材料在低碳烷烃氧化脱氢反应中显示出高的催化活性和优异的烯烃选择性,已在国际上形成新的研究热点。本文主要综述了近年来硼基材料催化低碳烷烃氧化脱氢的研究进展,阐述了不同硼基催化剂（h-BN、SiB₆、BC₄、硼单质等）对氧化脱氢烯烃选择性的影响,结合多种谱学（IR、XPS、NMR、SVUV-PIMS等）、动力学（分压、同位素效应、同位素标记等）证据和理论计算,探讨了硼基催化剂表面三配位的硼氧物种（B—OH/B—O）是引发烷烃氧化脱氢生成烯烃的活性位,主要遵循表面和气相自由基反应机理。总结了硼基催化材料氧化脱氢中存在的机遇和挑战,提升烯烃选择性是材料设计合成的主要方向,并提出后续硼基催化材料理性设计和实际应用的一些参考建议。     

催化裂解多产低碳烯烃工艺技术进展

介绍了不同原料、不同催化剂的各类催化裂解工艺的技术特点和工业应用情况,提出了催化裂解工艺应关注的问题及发展建议。     

反应温度对汽油催化裂解多产低碳烯烃的影响

利用自制的多产低碳烯烃催化剂在小型固定流化床装置上对催化裂化汽油、焦化汽油和直馏汽油的催化裂解性能进行了实验研究,考察了反应温度对催化裂解产物分布和低碳烃收率的影响.实验结果表明焦化汽油、催化汽油和直馏汽油最佳的催化裂解反应温度分别为580、600℃和680℃,随着反应物活性的降低而显著增加.乙烯的收率随着反应温度的升高呈抛物线增长;烯烃与正构烷烃有协同反应作用,烯烃能够加速正构链烷烃的反应速率;在烯烃存在下,芳烃会生成大量的焦炭;烯烃和链烷烃是生成低碳烯烃的主要来源,是催化裂解的理想组分;最佳催化裂解的反应物为催化汽油或者焦化汽油的轻馏分与直馏汽油的轻馏分的混合物.     

催化裂解多产低碳烯烃研究进展

本文从市场需求、催化裂解工艺、反应机理及裂解催化剂等几个方面综述了催化裂解多产低碳烯烃的研究进展,指出深入研究催化剂孔性质及酸性质与催化裂解性能之间的关系,设计具有梯级孔道分布,活性中心高度可接近性的新型催化剂,将会对低碳烯烃生产发挥重要的作用。     

Solubility of light alkanes and alkenes in ionic liquids

The solubility of light hydrocarbons in a variety of ionic liquids was studied, and it was found that ionic liquids containing Cu(Ⅰ) had higher solubility for hydrocarbons and alkene/alkane solubility selectivity, and Et₃NHCl-2.1CuCl ionic liquid was preferred. The effects of temperature and pressure on the solubility of light hydrocarbons were investigated for the selected ionic liquid. It was found that low temperature and high pressure were favorable for the dissolution of light hydrocarbons, and the alkene/alkane solubility selectivity decreased with the increase of temperature and pressure. The alkene/alkane solubility selectivity was above 8.3 at the temperature of 30℃ and the pressure of 0.2 MPa. The initial dissolution rate of hydrocarbons in ionic liquid was large, but it decreased rapidly with prolonging time, and the dissolution rate of alkenes was higher than that of alkanes at the same conditions. The alkene/alkane separation selectivity increased with decreasing content of alkenes in the mixture of alkenes and alkanes. Light hydrocarbons dissolved in ionic liquids could be desorbed by means of increasing temperature, restoring the dissolution capability of ionic liquids to hydrocarbons. Alkanes were easier to be desorbed than alkenes, and small-molecule hydrocarbons were easier to be desorbed than large-molecule hydrocarbons. The desorption percentage exceeded 92% under optimal conditions. Ionic liquid had a good reusable performance in the absorption and separation of light alkanes and alkenes. The solubility only decreased by less than 5% when it was reused five times, and the alkane/alkane solubility selectivity was basically not affected by reusing times. Software Gaussian 09 was used to study the interaction between anions of ionic liquids and light alkanes and alkanes, and the solubility difference of light alkenes and alkanes in different ionic liquids was well explained.     

小分子烷烃与烯烃在离子液体中的溶解性能

研究了多种离子液体对小分子烃类的溶解性能,发现含有Cu(Ⅰ)的离子液体对烃类具有较高的溶解度和烯烃/烷烃溶解选择性,优选出了Et3NHCl-2.1CuCl离子液体。考察了温度和压力对小分子烃类溶解性能的影响规律,发现低温和高压有利烃类的溶解,烯烃/烷烃溶解选择性随温度和压力的升高而减小;在30℃和0.2 MPa的条件下,烯烃/烷烃溶解选择性均在8.3以上。烃类在离子液体中的初始溶解速率较大,但随时间的延长快速降低,相同条件下烯烃的溶解速率高于烷烃的溶解速率。烯烃/烷烃分离选择性随混合气中烯烃含量的减小而增大。升温可以解吸出离子液体中的烃类,烷烃比烯烃容易解吸,优化条件下的解吸率可达92%以上。离子液体对小分子烷烃和烯烃的吸收分离具有良好的重复使用性能。利用Gaussian 09软件对离子液体的阴离子与烯烃、烷烃的作用进行了计算分析,解释了烯烃和烷烃在不同离子液体中溶解性能差异的原因。     

低碳烷烃催化脱氢与逆水煤气变换偶合转化的研究进展

本文综述了近年来国内外有关利用CO2为氧化剂经由逆水煤气变换与低碳烷烃脱氢进行偶合转化反应的研究状况。对几种CO2选择氧化低碳烷烃的反应研究进行了归纳总结。分析讨论了低碳烷烃催化反应与CO2偶合转化的作用机制,并提出了研究展望。     

Use of radiation-induced alkanes and alkenes to detect irradiated food containing lipids

To detect irradiated foodstuffs, we used the Nawar relation between lipid structure and radiolysis compounds, such as alkanes and alkenes. We first applied this method to sunflower, olive and peanut oils. Alkanes and alkenes were analyzed by gas chromatography with a head-space system for desorption and concentration of the volatile compounds. The detection limit, obtained both by estimation of the chromatogram area and by a blind trial, is better than 0.15 kGy. The continuity of detection with storage time was also studied. We have compared these results with those obtained by thermolysis: the same method can be used to detect ionized vegetable oils, even if they have been heated. In a second step, we studied three possible commercial situations—the irradiation of avocado-pears, fresh pilchards and poultry meat. Although we can use this lipid method to identify irradiated avocado-pears (for doses above 0.5 kGy) and poultry meat, it is impossible to apply it to fresh pilchards because numerous volatile compounds are already present before irradiation.     

Mechanism of first hydrogen abstraction from light alkanes on oxide catalysts

The activation mechanism of light alkanes is discussed in view of the catalytic properties, and both, bulk and surface properties of active phases. Among the most efficient catalytic systems, four are examined: VPO, Ti(Zr)PO, VSbO and MoVTeNbO. Different activation processes are proposed depending upon the catalyst used but all have the same H abstracting sites corresponding to O⁻. The formation of these relatively strong bound species may be related to structure defects (cationic vacancies, excess oxygen) or they might be created through thermally activated electron transfer. Particular emphasis is given to electrical conductivity measurements to evidence the presence of these active oxygen species. Member of the European CONCORDE Coordination Action     

Relative reactivities of alkanes in multi-component catalytic cracking reactions

An experimental technique is discussed for measuring relative reactivities of alkanes in the catalytic cracking of multi-component hydrocarbon mixtures over a heterogeneous, Y-zeolitebased catalyst at 250–350 °C. With the technique, ca. 0.1 l of an alkane mixture is evaporated and contacted with a catalyst, after which the mixture of reaction products and the unreacted feed enters the chromatographic column and is immediately analyzed. The technique is used to measure relative reactivities of 21 alkanes in a single experiment. The principal results of these experiments are similar to the results of single-component cracking: alkane reactivity rapidly increases with the increase of the carbon number, and methyl-branched alkanes are more reactive than linear alkanes. However, the variations in alkane reactivities as a function of their molecular weight and skeleton structure differ very significantly between single- and multicomponent experiments.     

重苯轻质化的初步探讨

对重苯和重芳烃的主要组分进行了比较,分析了从技术、政策、经济效益等方面利用重芳烃轻质化技术对重苯进行轻质化加工的可行性,并提出了重苯轻质化过程中需要注意的问题。     

重芳烃轻质化技术进展

重芳烃是生产轻芳烃的重要资源,重芳烃轻质化涉及加氢脱烷基、歧化和烷基转移等反应。TAC-9、ATA-11、Transplus等有代表性的国内外重芳烃轻质化反应工艺具有各自的优势与不足,未来重芳烃轻质化工艺技术发展应针对重芳烃轻质化反应的特点,开发以小颗粒、大孔径的分子筛作催化剂活性组元,增产附加值高的二甲苯。