1-丁烯催化裂解制丙烯和乙烯反应性能的研究

以MCM-49分子筛为催化剂,纯1-丁烯为原料,考察了反应温度对烯烃催化裂解制丙烯、乙烯反应性能的影响。选择适宜的反应温度条件能够有效地抑制副反应,从而提高丙烯、乙烯的总产率。     

甲醇制烯烃与催化裂解制烯烃的对比分析

现阶段,乙烯、丙烯等基础有机原料仍来源于传统的催化裂解、蒸汽裂解等工艺生产;甲醇制烯烃工艺线路是以煤或天然气为原料制取甲醇进而制取乙烯、丙烯的新兴生产工艺。本文简述了甲醇制烯烃、催化裂化制烯烃的工艺流程,从反应条件、催化剂、原料与产品分布等方面对比分析甲醇制烯烃相对于催化裂解的优点。     

轻烃资源优化及其经济效益分析

通过对炼厂干气、丙烷作乙烯裂解原料及烯烃歧化技术生产丙烯的经济性分析,认为炼厂干气是很好的裂解原料,具有投资低、消耗低的特点,并指出丙烷作乙烯原料合适的价格临界点以及烯烃歧化技术制取丙烯是适应今后丙烯的发展趋势,避免与中东低乙烯成本进行竞争的有效途径.     

轻烃资源优化及其经济效益分析

通过对炼厂干气、丙烷作乙烯裂解原料及烯烃歧化技术生产丙烯的经济性分析，认为炼厂干气是很好的裂解原料，具有投资低、消耗低的特点，并指出丙烷作乙烯原料合适的价格临界点以及烯烃歧化技术制取丙烯是适应今后丙烯的发展趋势，避免与中东低乙烯成本进行竞争的有效途径。     

试论催化热裂解制取乙烯及丙烯的工艺技术

以重油为原料的,在专业催化剂生产乙烯及丙烯的新型工艺技术解决了乙烯原料来源不足的问题。通过试验,对该工艺中催化剂的流化、水热稳定性及输送能力进行考察,注水量、反应温度、剂油比、反应压力等参数对生产效率的影响进行分析。通过研究,该工艺技术的原料广、成本低;催化剂水热性好、流化性能佳、反应温度较低;是较好的乙烯制备工艺。     

增产丙烯的烯烃转化技术

（1）ABBLumus公司的OCT技术。ABBLummus公司的OCT技术将乙烯转化为丙烯的选择性近100％，将丁烯转化为丙烯的选择性为97％，丁烯总转化率为85％～92％（丁烯进料中正丁烯质量分数为50％～95％）。进料中的乙烯和丁烯可来自蒸汽裂解装置和各种炼油厂的生产过程，浓度也可不相同，丁烯也可来自乙烯二聚装置。OCT技术采用固定床反应器，催化剂是载于硅藻土上的W03和MgO。催化剂可连续再生，催化剂结焦采用氮气加空气清焦。原料中的1～丁烯在MgO作用下异构化为2-丁烯，然后与乙烯由W03歧化生成丙烯。在乙烯塔内分离出未反应的乙烯返回反应器循环使用，丙烯可以在丙烯塔内分离得到，因在反应中无丙烷生成，无须进一步提纯即可得到聚合级丙烯。     

HZSM-5催化剂上甲醇制丙烯反应条件的研究

以HZSM-5分子筛为催化剂,在固定床反应器中考察了反应温度和原料空速对甲醇制丙烯性能的影响。结果表明,随着反应温度的升高,乙烯和丙烯选择性均增加,但温度过高容易引起催化剂的失活;而随原料空速的增大,甲醇转化率、乙烯和丙烯的选择性均呈下降趋势。最佳的反应条件为反应温度为460°C,原料液时空速为1.4 kg(Methanol)/kg(cat.).h。对添加粘结剂与未添加粘结剂成型后的催化剂性能比较,表明添加粘结剂成型后,甲醇转化率和丙烯选择性有所下降。     

埃克森美孚改善乙烯和丙烯选择性的新型催化剂

美国埃克森美孚化学公司开发出新型磷酸硅铝分子筛甲醇制丙烯催化剂。该催化剂催化活性显著提高，可改善乙烯和丙烯选择性。由于石脑油、乙烷及丙烷等乙烯裂解原料价格上涨导致乙烯和丙烯等原料价格的大幅上扬，正开发多种烯烃原料替代生产方法，如甲烷为原料的甲醇制丙烯MTO工艺技术。该技术可以使不便利用天然气的企业通过生产甲醇然后制成高价值的乙烯和丙烯。MTO工艺技术商业化存在的主要问题是催化剂的过快结焦，埃克森美孚化学公司开发的新型催化剂解决了这一难题。     

炼油产乙烯裂解原料的优化利用及经济分析

炼油厂的一次、二次加工油品及副产气体是乙烯裂解炉的主要原料来源。主要对炼油产乙烯裂解原料进行优化利用,分析不同优质裂解原料对三烯收率影响及其经济性,为乙烯装置原料选择,优化降本,根据市场需求生产乙烯、丙烯或丁二烯产品,提高经济效益提供参考。     

阿尔科和壳牌公司开发交互置换化学

<正> 由菲利浦斯石油公司开发的烯烃转化技术工艺过程已首次应用在得克萨斯州切内维尤、新建13.6万吨/年工业化的丙烯装置。这套由阿尔科的子公司里昂德尔石油化学公司操作的装置,可从裂解装置得到的原料乙烯生产聚合级丙烯。先利用菲利浦斯二聚工艺,使乙烯反应生成丁烯-2,丁烯-2再通过菲利浦斯三烯工艺,与乙烯生成丙烯。阿尔科公     

Effects of Addition of Na and S to Alumina Catalyst for the Selective Reduction of Nitrogen Monoxide with Ethene in Excess Oxygen

The addition of Na and S into alumina catalysts brought about a decrease in the catalytic activity for the reduction of NO with ethane in excess oxygen. Aluminas containing Na or S in different amounts were subjected to activity tests for the related reactions to elucidate the causes of the suppressive effects of the addition of Na and S on the reduction of NO. The reactions taken as test reactions were the oxidation of NO with oxygen, the reaction of NO₂ with ethene in the absence of oxygen, and the reaction of ethene with oxygen. The addition of Na suppressed the oxidation of NO, and the reaction of NO₂ with ethene to form N₂, but promoted the reaction of ethene with oxygen to a great extent. The addition of Na also caused the formation of NO in the reaction of NO₂ with ethene. The changes which the addition of Na brought about are all unfavorable directions for the reduction of NO. The most important effect of the addition of Na on the decrease in the reduction of NO is suggested to be due to the enhancement of the reaction of ethene with oxygen. The addition of S suppressed the oxidation of NO to a great extent, but did not affect much the reaction of ethene with oxygen. Like the case of the Na addition, the addition of S caused the formation of NO in the reaction of NO₂ with ethene.     

A reactive oxygen state at a barium promoted Au (100) surface: the oxidation of ethene at cryogenic temperatures

Although Au (100) does not adsorb oxygen at either 295 K or 80 K, a barium modified Au(100) surface is active in oxygen dissociation resulting, through surface diffusion of oxygen adatoms, in the formation of a chemisorbed oxygen adlayer. This oxygen species is inactive for ethene oxidation, as is the oxygen species pre-adsorbed at an Au(100)–Ba surface at 80 K, and the clean Au(100)–Ba surface. However, when molecularly adsorbed ethene present at a Au(100)–Ba surface at 80 K is exposed to dioxygen and warmed to 140 K, surface carbonate is observed. We conclude that a transient oxygen species is the oxidant.     

The synthesis of ethene during the oxidative coupling of methane

The effect of residence time on the selectivity of a MgO catalyst for the formation of ethene in the methane coupling reaction has been studied. It is found that the variation in ethene selectivity with this time follows opposite trends depending on the experimental conditions. In both cases the results show a positive intercept at zero residence time which may indicate that ethene is a primary product. However, calculations show that gas phase radical reactions just above the catalyst surface could account for the ethene observed even at very short residence times. It is concluded that experiments such as these cannot reliably distinguish between primary and secondary product formation. A SmOCl catalyst was studied and it was found that HCl was released when wet gases were passed over the catalyst at relatively low temperatures. It is concluded that much of the ethene produced over oxychloride catalysts may be produced by gas phase reactions involving chlorine radicals.Based in part on a paper given at the Royal Society-U.S.S.R. Academy Workshop on Catalysis and Surfaces, Oxford, April 8–10, 1989.     

The importance of heterogeneous and homogeneous reactions in oxidative coupling of methane over chloride promoted oxide catalysts

The formation of ethene from ethane and methane in a silica reactor has been studied both in the presence and in the absence of chloride-containing catalysts. Some homogeneous conversion of ethane to ethene occurs in the gas phase through direct dehydrogenation, oxidative dehydrogenation, and, when HCl is present, chlorine radical induced reactions. Methyl chloride is detected in the gas phase but has no influence on the conversion of ethane to ethene. It is shown that under typical catalytic conditions, when a chloride-modified catalyst is used, ethane is mostly produced in the catalyst bed.     

V–BaCO3 catalysts for the oxidative dehydrogenation of ethane

A new type of supported vanadium oxide catalyst V–BaCO₃, which consists of barium orthovanadate Ba₃(VO₄)₂ and BaCO₃ phases, has been used in the oxidative dehydrogenation of ethane. The catalyst with the ratio of V/Ba from 0.1 to 0.3 exhibited high catalytic activity for oxidative dehydrogenation of ethane, with particularly high activity for ethene production.     

Metathesis of 1-butene and ethene to propene over mesoporous W-KIT-6 catalysts: the influence of Si/W ratio

Journal of Porous Materials - Mesoporous W-KIT-6 catalysts with various Si/W ratios were prepared by one-pot direct hydrothermal reactions and were studied in metathesis of 1-butene and ethene to...     

Phosphorus esters of 1-dopyl-1,2-(4-hydroxyphenyl)ethene as effective flame retardants for polymeric materials

1-Dopyl-1,2-(4-hydroxyphenyl)ethene has been converted to phosphorus diesters, 1-dopyl-1,2-(4-diphenylphosphatophenyl)ethene (BDE-DPP), and 1-dopyl-1,2-(4-dopyloxyphenyl)ethene (BDE-DOPO) which have been fully characterized using spectroscopic and thermal methods and assessed as flame retardants in DGEBA epoxy (diglycidyl ether of bisphenol A). Both are effective flame retardants. The ester containing diphenylphosphato groups (BDE-DPP) acts primarily in the condensed phase while that containing only dopyl units acts predominately in the gas phase. DGEBA epoxy containing sufficient 1-dopyl-1,2-(4-dopyloxyphenyl)ethene to provide 2% phosphorus displays a limiting oxygen index of 28, a peak heat release rate of 506 W/g, and a total heat release of 24 kJ/g.     

1-丁烯催化裂解制丙烯和乙烯反应性能的研究

以MCM-49分子筛为催化剂,纯1-丁烯为原料,考察了反应压力和空速对烯烃催化裂解制丙烯,乙烯反应性能的影响.选择适宜的反应压力和空速条件能够有效地抑制副反应,从而提高丙烯,乙烯的总产率。     

Catalytic cracking of 1-butene to propene and ethene on MCM-22 zeolite

Catalytic cracking of butene to propene and ethene was investigated over HMCM-22 zeolite. The performance of HMCM-22 zeolite was markedly influenced by time-on-stream (TOS) and reaction conditions. A rapid deactivation during the first 1 h reaction, followed by a quasi-plateau in activity, was observed in the process along with significant changes in product distributions, which can be attributed to the fast coking process occurring in the large supercages of MCM-22.

Properly selected reaction conditions can suppress the secondary reactions and enhance the production of propene and ethene. According to the product distribution under different butene conversion, we propose a simple reaction pathway for forming the propene, ethene and by-products from butene cracking.

HMCM-22 exhibited similar product distribution with the mostly used high silica ZSM-5 zeolite under the same conversion levels. High selectivities of propene and ethene were obtained, indicating that the 10-member ring of MCM-22 zeolite played the dominant role after 1 h of TOS. However, MCM-22 exhibited lower activity and stability than that on high silica ZSM-5 zeolite with longer time-on-stream.