N-杂环的催化氧化脱氢的研究进展

由于氢气高质量能量密度(120MJ·kg^(-1))和无碳燃烧产物,其生产正越来越多地与过剩的可再生电力相结合。但是以氢作为储能介质仍然无法大规模利用,主要障碍在于氢不利的元素特性。N-杂环或其他能与氢气结合并在环境条件下储存的化合物,为克服经典的氢气储存加氢和脱氢释放有关的问题提出了一个替代方案。探索一种简单、高效、稳定和绿色的催化体系是实现这一典型转化的关键。总结了过去5年来开发Ru、Ni、Co、Fe和Mn催化剂与n杂环化合物催化氧化脱氢反应所取得的显著进展,期望这一领域的研究结果能够启发其他人进一步制备新型高效、可控和绿色的催化剂,用于氢的借用或氢气转移的应用,从而能够促进在不久的将来建立适合燃料电池的供氢体系。

用于二乙醇胺催化氧化脱氢的Cu-ZrO_2催化剂的制备与表征

采用共沉淀法制备了二乙醇胺催化氧化脱氢生产亚氨基二乙酸二钠盐用的Cu -ZrO2 催化剂。考察了不同制备条件对催化剂催化氧化反应性能和催化剂结构的影响。实验结果表明 ,催化剂中和终止 pH值、Cu与Zr原子的量比以及焙烧温度是影响催化剂性能的主要因素。经TG、XRD和外观分析 ,优质催化剂其中间体铜锆氢氧化物外观呈现亮而脆的绿色、密度大于1 72g/cm3 、热失重温度范围为 15 0～ 5 30℃ 。

反式-4-乙酰氨基环己醇催化氧化脱氢生成4-乙酰氨基环已酮反应的研究

为解决4-乙酰氨基环己酮传统合成工艺大量铬废渣及酸性废液排放的问题,研究了反-4-乙酰氨基环己醇催化氧化脱氢制备4-乙酰氨基环己酮的绿色化新工艺。探讨了反-4-乙酰氨基环己醇在液-固相反应体系中以30%H2O2(质量分数)为氧化剂,催化氧化脱氢生成4-乙酰氨基环己酮的反应规律。实验结果表明,WO3是实现这一反应的主要催化活性组分,二氧化硅是较好的载体;以25%WO3/Si O2(质量分数)为催化剂,氧化剂和原料物质的量之比为5.1,90℃反应4 h时,目标产物4-乙酰氨基环己酮的得率可达96%左右。此工艺过程较传统的铬酸氧化法对环境友好,但实验过程发现活性组分WO3在催化剂重复使用过程中易于流失,催化剂重复使用性能尚有待于改进。

改性铁酸锌催化剂的合成及其丁烯氧化脱氢活性

采用共沉淀法制备铁酸锌催化剂,考察改性元素Mg、B、Zr、Ce、La对铁酸锌催化剂结构和丁烯氧化脱氢性能的影响。采用XRD、TEM和N2吸附-脱附对镧改性铁酸盐催化剂进行金属元素组成的优化研究,确认镧元素在催化剂中存在的形态和作用。结果表明,La改性铁酸锌催化剂晶粒粒径(20~50) nm,具有较大的比表面,主要活性组分是α-Fe2O3和ZnFe2O4,催化剂的活性随着Fe含量的升高而升高,n(Fe)∶n(Zn)∶n(La)=4∶1∶1催化剂具有最高的催化活性,反应温度380℃时,其TOF值2.1×10^-3 molbutene·molsurface-Fe·s^-1。

高氮馏分油加氢精制催化剂的研制

以含SiO2和/或TiO2的γ-Al2O3为复合载体、以W-Mo-Ni为活性金属组分,采用分步等体积浸渍法制备了一系列三叶草形加氢精制催化剂。采用X荧光射线、N2吸附比表面积、X射线衍射、扫描电镜等对催化剂结构进行了表征。在反应压力8.0MPa、反应温度340℃、氢油体积比600∶1、体积空速1.5h-1条件下,测定了催化剂的机械强度和表面酸性,采用100mL固定床加氢反应装置进行了催化剂性能评价。结果表明,所研制的催化剂对高氮劣质馏分油具有优异的加氢脱硫、脱氮及烯烃饱和性能,其中催化剂W-Mo-Ni/SiO2-TiO2-Al2O3的脱硫率可达到98%,脱氮率可达到97%和烯烃饱和率98%。

乙烷氧化脱氢与乙酸乙烯酯的联合生产

本发明涉及生产乙烯和醋酸乙烯(VAM)的集成方法,包括在第一反应区中在氧化脱氢催化剂存在下使包括乙烷和任选乙烯的气流与含氧气流接触。活性脱氢条件,以产生包括乙烷、乙烯、乙酸和水以及任选的其他化合物的第一产品流.

国外瞭望

低压炼厂干气回收和蒸汽裂解相结合技术 据报道,鲁姆斯公司开发出低压炼厂干气回收与蒸汽裂解相结合的技术,该技术实际上是一种用丙烷作吸收剂的油吸收工艺。

技术需求

二乙醇胺脱氢氧化产物及机理的分析研究联系方式：在IDA草甘膦生产过程中，二乙醇胺脱氢（氧化）制备亚氨基二乙酸是非常关键的一步。二乙醇胺生产亚氨基二乙酸是一个催化氧化脱氢过程，该反应的机理在各类文献中有多种不同解释，还未清楚其中间产物和控制步骤，因此实际生产中对于反应终点的控制尚不完善，有待进一步地研究和改进。

Electrospinning synthesis of porous boron-doped silica nanofibers for oxidative dehydrogenation of light alkanes

The discovery of the high activity and selectivity of boron-based catalysts for oxidative dehydrogenation(ODH)of alkanes to olefins has attracted significant attention in the exploration of a new method for the synthesis of highly active and selective catalysts.Herein,we describe the synthesis of porous boron-doped silica nanofibers(PBSNs)100-150 nm in diameter by electrospinning and the study of their catalytic performance.The electrospinning synthesis of the catalyst ensures the uniform dispersion and stability of the boron species on the open silica fiber framework.The one-dimensional nanofibers with open pore structures not only prevented diffusion limitation but also guaranteed high catalytic activity at high weight hourly space velocity(WHSV)in the ODH of alkanes.Compared to other supported boron oxide catalysts,PBSN catalysts showed higher olefin selectivity and stability.The presence of Si-OH groups in silica-supported boron catalysts may cause low propylene selectivity during the ODH of propane.When the ODH conversion of ethane reached 44.3%,the selectivity and productivity of ethylene were 84%and 44.2%g_(cat)^(-1)s^(-1),respectively.In the case of propane ODH,the conversion,selectivity of olefins,and productivity of propylene are 19.2%,90%,and 76.6 jimol g_(cat)^(-1)s^(-1),respectively.No significant variations in the conversion and product selectivity occurred during 20 h of operation at a high WHSV of 84.6 h^(-1).Transient analysis and kinetic experiments indicated that the activation of O2 was influenced by alkanes during the ODH reaction.

Ordered macroporous boron phosphate crystals as metal-free catalysts for the oxidative dehydrogenation of propane

Ordered macroporous materials with rapid mass transport and enhanced active site accessibility are essential for achieving improved catalytic activity.In this study,boron phosphate crystals with a three-dimensionally interconnected ordered macroporous structure and a robust framework were fabricated and used as stable and selective catalysts in the oxidative dehydrogenation(ODH)of propane.Due to the improved mass diffusion and higher number of exposed active sites in the ordered macroporous structure,the catalyst exhibited a remarkable olefin productivity of^16 golefin gcat^-1 h^-1,which is up to 2–100 times higher than that of ODH catalysts reported to date.The selectivity for olefins was 91.5%(propene:82.5%,ethene:9.0%)at 515℃,with a propane conversion of 14.3%.At the same time,the selectivity for the unwanted deep-oxidized CO2 product remained less than 1.0%.The tri-coordinated surface boron species were identified as the active catalytic sites for the ODH of propane.This study provides a route for preparing a new type of metal-free catalyst with stable structure against oxidation and remarkable catalytic activity,which may represent a potential candidate to promote the industrialization of the ODH process.

Influence of Alumina Content on Catalytic Performance of PtSn/Al_2O_3/SBA-15 Catalysts for Propane Dehydrogenation

The alumina-modified SBA-15 （A12OJSBA-15） zeolite was prepared in a non-aqueous system by using toluene as the solvent, and was used to support the PtSn-based catalyst for propane dehydrogenation. The BET surface area mea- surements, hydrogen chemisorption, FT-IR spectroscopy, NH3-TPD, XPS and TPO techniques were used to characterize the catalysts. Test results showed that the addition of alumina not only could modify the acid function of the support but also the structure of the metallic phase, thus affecting their catalytic properties. Among these catalysts studied, the PtSn/AI203 （5%）/ SBA-15 catalyst exhibited a best catalytic performance in terms of propane conversion and selectivity to propene. The high catalytic performance might be attributed to the relatively good Pt metal dispersion and/or the strong interaction between Pt and Sn species.

Acidic Montmorillonite/Cordierite Monolithic Catalysts for Cleavage of Cumene Hydroperoxide

In this work,a series of acidic montmorillonite/cordierite monolithic catalysts were prepared by a coating method using silica sol as the binder.The morphology and structure of the acidic montmorillonite/cordierite samples were characterized by means of X-ray diffraction(XRD),N_2 adsorption/desorption isotherms,and scanning electron microscope(SEM).The cleavage of cumene hydroperoxide(CHP) in a conventional fixed-bed reactor was chosen as a model reaction to evaluate the catalytic activity of the monolithic catalysts.The influences of acidic montmorillonite loading,reaction temperature.CHP concentration,and weight hourly space velocity(WHSV) on the catalytic activity and selectivity of phenol were studied.The results indicated that the obtained acidic montmorillonite/cordierite monolithic catalysts were firm and compact,and the loading of acidic montmorillonite was found to reach 40%(by mass) after three coating operations.The surface area of acidic montmorillonite/cordierite catalysts increases greatly as acidic montmorillonite loading increases due to higher surface area of acidic montmorillonite.Under the optimal reaction conditions(acidic montmorillonite loading of 32.5%(by mass),temperature of 80 ℃,a mass ratio of CHP to acetone of 1:3,and WHSV of CHP of 90 h^(-1)),the conversion of CHP can reach 100%,and the selectivity of phenol is up to 99.8%.

Cu-catalyzed deoxygenative gem-hydroborylation of aromatic aldehydes and ketones to access benzylboronic esters

Organoboron compounds are widely used in synthetic chemistry,pharmaceutical chemistry and material chemistry.Among various organoboron compounds,benzylboronic esters are unique and highly reactive,making them suitable benzylation reagents.At present,the synthetic methods for the syntheses of benzylboronic esters are still insufficient to meet their demands.It is necessary to develop novel and practical methods for their preparation.In this work,a novel copper‐catalyzed deoxygenative gem‐hydroborylation of aromatic aldehydes and ketones has been developed.This direct and operationally simple protocol provides an effective approach for the synthesis of a variety of primary and secondary benzylboronates,in which broad functional group tolerance was presented.Widely available B2pin2(pin=pinacol)was used as the boron source and alcoholic proton was applied as the hydride source.

Progress in the Technology for Desulfurization of Crude Oil

The poor quality of crude oil obviously leads to high sulfur contents of oil products, and the technology for desulfurization of crude oil is urgently needed so that the sulfur contents in petroleum product could be reduced from the root. This paper describes the progress in technology for desulfurization of crude oil. The present technologies for desulfurization of crude oil include caustic washing, dry gas desulfurization, hydrodesulfurization （HDS）, etc. The new combined technologies for desulfurization of crude oil being studied are： biodesulfurization （BDS）, hydrogenationbacterial catalysis, the microwave-catalytic hydrogenation, the BDS-OD-RA desulfurization and oxidative desulfurization in electrostatic fields, and the ultrasonic/microwave-catalytic oxidation applied in our lab, with their development trends being also discussed.

Preparation of Alumina Binder-Added PtSnNa/AlSBA-15 Catalyst for Propane Dehydrogenation

Abstract： The present article compares the propane dehydrogenation performance of alumina binder-added PtSnNa/ A1SBA-15 catalysts prepared via three different procedures in comparison with the performance of a binder-free PtSnNa/ AISBA-15 catalyst. All these catalysts have been investigated by reaction tests and some physico-chemical characterizations such as BET, H2 chemisorption, catalytic grain crushing strength, NHa-TPD and TPO analyses. Test results showed that the addition of alumina binder could enhance the mechanical strength of catalyst evidently. Moreover, the different preparation procedures not only modified the characteristics of both acid and metal functions but also affected the coke deposition on the catalysts. Among these catalysts studied, the catalyst prepared by impregnation followed by the agglomeration of alumi- na binder had exhibited the highest catalytic activity and stability compared with other catalyst samples undergoing different preparation procedures. The possible reason may be attributed to the highest metallic dispersion and the strong interactions among Pt, Sn and the support.

Hydrogen sulfide removal by catalytic oxidative absorption method using rotating packed bed reactor

Using catalytic oxidative absorption for H_2S removal is of great interest due to its distinct advantages. However,traditional scrubbing process faces a great limitation in the confined space. Therefore, there is an urgent demand to develop high-efficiency process intensification technology for such a system. In this article, H_2S absorption experimental research was conducted in a rotating packed bed(RPB) reactor with ferric chelate absorbent and a mixture of N_2 and H_2S, which was used to simulate natural gas. The effects of absorbent p H value, gas–liquid ratio, gravity level of RPB, absorption temperature and character of the packing on the desulfurization efficiency were investigated. The results showed that H_2S removal efficiency could reach above 99.6% under the most of the experimental condition and above 99.9% under the optimal condition. A long-time continuous experiment was conducted to investigate the stability of the whole process combining absorption and regeneration. The result showed that the process could well realize simultaneous desulfurization and absorbent regeneration, and the H_2S removal efficiency kept relatively stable in the whole duration of 72 h. It can be clearly seen that high gravity technology desulfurization process, which is simple, high-efficiency, and space intensive, has a good prospect for industrial application of H_2S removal in confined space.

Dynamics of liquid-phase catalytic oxidation of hydrogen sulfide removal in rural biogas

Hydrogen sulfide in rural biogas was removed with liquid-phase catalytic oxidation.By using rare earth as catalyst,and sulfosalicylic acid as stabilizer,H2S purification efficiency could increase as high as 96%,and sulfur capacity of the composite solution was about 3 g/L.The results show that purification efficiency was affected by catalyst addition,pH,experimental temperature,and sulfur capacity.The parameters effects on catalytic oxidation were studied,and the optimized conditions were that Fe3+ concentration 0.08 mg/L,reaction temperature 70°C,pH 9.0,with a absorption solution volume of 50 mL,a gas flow rate 200 mL/min,and H2S mass concentration of 1.58-2.02 mg/m3.

Oxidative Dehydrogenation of Isobutane to Isobutene on FSM-16 Doped with Cr and Related Catalysts

The oxidative dehydrogenation of isobutane to isobutene was examined for the use in the preparation of FSM-16 and related compounds doped by chromium with expectations that a yield of isobutene of greater than 8% could be achieved. The activity depended on the molding procedure of the catalyst and the doping method of the chromium species. In the present study, 8.8% and 8.3% of the yield of isobutene were obtained at 0.75 h and 6 h on-stream for the catalyst （Cr-loading; 6.2 wt.%） molded using wet treatment hut not pressurization treatment, in which the chromium species were directly added into the aqueous solution containing raw FSM-16 （hydrated sodium silicate powder） at an initial stage of the catalyst preparation. The structure information was based on XRD （X-ray diffraction）, the specific surface area was determined using a conventional BET （Brunauer-Emmett-Teller） nitrogen adsorption and the loading of chromium was estimated using ICP （inductively coupled plasma）. All those parameters combined with the molding method indicated that the catalytic activity was more influenced by the loading of chromium into bulk but not on surface of the catalyst rather than by the hexagonal structure of FSM-16 and the surface area.

Synthesis of Silica-Dispersed NiMo Hydrodesulfurization Catalysts

Silica-dispersed NiMo hydrodesulfurization catalysts were synthesized by the deposition-precipitation method. For comparative purposes, bulk NiMo catalysts were obtained by co-precipitation. The silica-dispersed NiMo catalyst had highly active metals content. Silica was employed to disperse active metals for full utilization of active components. The BET analysis showed that the silica-dispersed NiMo catalysts had a high surface area （147.0 m2/g） and pore volume （0.27 mL/g）, whereas the bulk NiMo catalysts exhibited a very low surface area （87.5 m2/g）. Transmission electron microscopy results proved that the active components were dispersed on the SiO2 substrate. X-ray diffraction patterns of the silicadispersed NiMo catalyst and the bulk NiMo catalyst were indexed to NiMoO4. The hydrodesulfurization activity of silicadispersed NiMo catalysts was much higher than that of reference catalysts and could be up to twice greater than those of commercial NiMo alumina-supported systems per gram of catalyst. The activity testing results also demonstrated that the silica-dispersed NiMo catalyst was an effective hydrodesulflarization catalyst.