Hydroformylation of Alkenes with Rhodium Catalyst in Supercritical Carbon Dioxide

1-Octene, 1-decene and styrene have been hydroformylated using a CO₂-philic fluorous ligand associated with a rhodium catalyst. The effect of P/Rh molar ratio, partial pressure of CO/H₂ and total pressure of carbon dioxide were studied. When 1-octene was used as the substrate, high conversion and selectivity in aldehydes were observed using low rhodium concentration and low P/Rh ratios.     

负载型钌炭加氢催化剂的工艺研究

通过对负载型钌炭催化剂的制备工艺的研究,分析讨论了载体种类、制备工艺中的负载和还原操作对钌炭催化剂性能的影响。研究结果表明:在催化剂的制备过程中,活性炭载体、负载方式和还原操作对表面活性金属的分散度有影响,从而造成催化剂的性能差异。选择椰壳炭为载体、沉淀法进行活性金属的负载,经过液相法硼氢化钠还原得到的催化剂表面活性金属的分散度高,催化剂在苯部分加氢反应中具有高活性和高选择性,环己烯的收率达到55%。     

用于甲烷二氧化碳重整反应的Ni基催化剂的研究进展

对用于甲烷二氧化碳重整反应的Ni基催化剂的研究进展进行了概述,详细分析了Ni金属结构形态、载体、助剂及制备方法等方面对Ni基催化剂活性、稳定性及抗积碳性能的影响。     

脱碳工艺对制氢成本的影响分析

介绍了轻烃水蒸气转化制氢装置中中变气脱碳工艺,分析了制氢流程中脱碳工序的利弊。通过对10000Nm3／h天然气制氢装置投资和能耗计算,分析了不同脱碳工艺流程对制氢成本的影响,结果表明：根据市场情况确定脱碳工艺,可以实现经济效益的最大化。     

新型DMC催化剂催化二氧化碳与环氧丙烷共聚动力学探究

关于二氧化碳聚合催化剂的研究是一个新兴的并具有长远意义的热门课题,但是目前有关双金属氰化物催化剂(DMC)催化二氧化碳与环氧化物聚合的催化机理至今在学术界尚无定论。因此,文章探讨在一种新型高效的双金属催化剂(DMC)催化下,二氧化碳与环氧丙烷的共聚机理,推导出其动力学方程,并对新的反应动力学原理进行推导及验证。     

相转移催化H2O2环氧化环己烯合成环氧环己烷

对反应控制相转移催化剂制备方法进行了改进,催化剂产率可达94%,并用红外光谱(IR)和元素分析对催化剂进行了表征;将催化剂用于以w(H2O2)=34.5%为氧化剂,以质量分数76.7%的工业粗环己烯为原料合成环氧环己烷;探讨了反应时间、反应温度、环己烯与H2O2的摩尔比、催化剂用量、溶剂用量等因素对反应的影响。获得的较佳合成条件(以0.08 mol H2O2计)为:反应温度40℃,反应时间90 m in,催化剂用量0.6 g,n(C6H10)∶n(H2O2)=2.5∶1,溶剂1,2-二氯乙烷70 mL。该条件下环氧环己烷平均选择性为96.1%,环氧环己烷的平均收率达91.7%。将回收的催化剂用于反应,环氧环己烷的平均选择性和平均收率分别为95.3%和90.9%。     

二氧化碳和环氧化合物共聚反应的研究进展

综述了二氧化碳与环氧化合物在不同催化体系下反应形成高分子化合物的反应机理、反应实例及研究进展。     

二氧化碳催化合成低碳烯烃的催化剂研究进展

二氧化碳催化合成低碳烯烃是二氧化碳固定最有前景的方法之一.本文根据国内外学者对二氧化碳催化合成低碳烯烃的2条路线进行了综述,并对其在未来的发展进行展望.     

Chemical Fixation of Carbon Dioxide to Propylene Carbonate Using Smectite Catalysts with High Activity and Selectivity

The reaction of propylene oxide and carbon dioxide to propylene carbonate was carried out using Mg-, Ni- and Mg-Ni-containing smectite catalysts which contain different amounts of alkali atoms such as sodium, potassium and lithium. These catalysts are highly active and selective for this reaction. The catalytic activity strongly depends on the elemental composition of the catalyst used. Particularly the amount of alkali atoms incorporated in the catalyst is the most important factor governing the catalytic performance. The most active catalyst among those prepared in the present study shows a turnover number of 105 mmol/g for the propylene carbonate formation, which is the highest turnover number compared with those reported so far (10 mmol/g) for the title reaction.     

Mechanistic Aspects of Formation of Chiral Ruthenium Hydride Complexes from 16‐Electron Ruthenium Amide Complexes and Formic Acid: Facile Reversible Decarboxylation and Carboxylation

The 16‐electron amide complex, Ru[(R,R)‐TsNCHPhCHPhNH](η⁶‐p‐cymene) (Ts=p‐toluenesulfonyl, Ph=C₆H₅) readily reacts with formic acid to give the corresponding formate complex, which subsequently undergoes decarboxylation leading to the hydride complex with release of CO₂. The reaction of this hydride complex with CO₂ under mild reaction conditions, a pressure of 10 atm and even at −78 °C, proceeds rapidly to give the corresponding formate complex almost quantitatively. Thus, the reversible decarboxylation and carboxylation takes place with or without the aid of a metal‐NH bifunctional effect of the Ru complexes.     

沉淀温度对CO2加氢合成二甲醚催化剂的影响

考察了沉淀温度对二氧化碳加氢合成二甲醚催化剂CuO-ZnO-Al2O3/HZSM-5的影响,研究结果表明,沉淀温度为343 K时,所制备的催化剂前驱体的晶形完整且晶相组成均一,焙烧后的催化剂中CuO和ZnO的相互分散程度较好,催化剂中氧化铜物种比较容易还原,复合催化剂表面具有较强的酸性中心,对于二氧化碳加氢直接合成二甲醚的催化活性最为理想.     

超声处理对活性炭表面形态及负载催化剂活性的影响

采用超声预处理活性炭,并用N_2物理吸附、X射线能谱仪(EDS)、透射电镜(TEM)、和场发射扫描电镜(FE-SEM)等表征手段,研究了超声预处理条件对活性炭表面结构、化学成分及表面形貌以及所负载钌基氨合成催化剂性能的影响。研究结果表明,超声预处理活性炭,可有效降低活性炭表面灰分和不稳定含氧基团的含量,从而提高所负载催化剂的活性。在实验范围内,当超声频率为39.0 kHz,功率为100w时,在10 000 h~(-1),10.0 MPa和400℃的反应条件下,钌基催化剂的反应速率达到了97.6 mmol/(g·h)。     

Catalyst Synthesis Using Supercritical Carbon Dioxide: A Green Route to High Activity Materials

Catalysts are intrinsically considered to be a key part of green and sustainable technology. However, many catalysts require the use of non-green methodologies during their manufacture. With the increased focus on green issues that is now emerging, it is essential that some attention is focussed on synthesing catalysts using green approaches. However, it is critical that any material prepared using these new green methods has to exhibit key advantages over current technology, such as significantly enhanced performance, if they are o be adopted in this competitive industry. Here the use of supercritical carbon dioxide as an anti-solvent is discussed and two examples, namely the synthesis of vanadium phosphate and ceria-supported gold catalysts, are described using supercritical carbon dioxide in the preparation. Both of these examples demonstrate significant advantages with respect to higher activity when compared with catalysts prepared using standard methods.     

Reforming of Methane with Carbon Dioxide over a Catalyst Consisting of Ruthenium Metal and Cerium Oxide Supported on Mordenite

Reforming of CH₄ with CO₂ proceeds at 400 °C over a catalyst consisting of ruthenium metal and CeO₂ highly dispersed on mordenite. The catalyst, Ru-CeO₂/MZ, is highly active for the reforming of CH₄ under the conditions at which a carbon formation reaction is thermodynamically apt to take place. The reforming selectively forms H₂ and CO. An increase in the weight of the catalyst resulting from carbon deposits was scarcely observed. IR spectra for the catalyst indicate that the reforming proceeds via the formation of the intermediate species such as Ru-CO and Ru-CH_x on the surface of ruthenium. The data of H₂ adsorption support the idea that ruthenium is highly dispersed in Ru-CeO₂/MZ.     

T907型水解催化剂用于不同原料COS水解的性能与应用

本文介绍了T907型COS水解催化剂在高CO₂煤气、一氧化碳、二氧化碳和液相丙烯中COS水解的研究和应用。试验及工业应用表明，T907型催化剂是一种适用于各种气液进料、具有高水解转化率和抗氧毒性能的优良催化剂。在气固催化反应中，其最佳使用温区为100~120℃；在气液相催化反应中，其最佳使用温区为15~40℃。     

碱性催化剂作用下CO_2与甲醇直接合成碳酸二甲酯的探索性研究

选用 K2 CO3和 CH3I为催化剂 ,在高压机械搅拌反应釜中探索了 CO2 和甲醇直接合成 DMC。研究了所用两种催化剂的适宜配比及适宜的反应时间 ,并在反应温度 6 0～ 1 2 0℃和反应压力 4.5～ 8.0 MPa范围内研究了其对液相出口中 DMC含量的影响     

Simultaneous Absorption of Hydrogen Sulfide and Carbon Dioxide into di-isopropanolamine Solution

The simultaneous absorption of hydrogen sulfide and carbon dioxide into di-isopropanolamine (DIPA) solution was investigated in a 183 cm long, 2.72 cm OD wetted-wall column at atmospheric pressure. The influence of liquid flow rate, gas flow rate, temperature and liquid concentration on the absorption rate, overall gas-phase mass transfer coefficient and selectivity factor were studied at a constant gas feed ratio. The results show that the absorption rate of CO₂ increases rapidly with increasing liquid flow rate (the Reynolds number of the turbulent liquid film ranges from 2600 to 4350) but increases moderately with increasing gas flow rate (G = 18-91 L/min), indicating that it is liquid-phase mass transfer controlled. In contrast, the absorption rate of H₂S increases very slowly with increasing liquid flow rate but increases rapidly with increasing gas flow rate, indicating that it is gas-phase mass transfer controlled. The absorption rate of CO₂ also increases with increasing temperature (26-80°C) but H₂S absorption rate decreases with increasing temperature. When the concentration of DIPA solution increases from 0.2 to 2.6 mol/L, the absorption rate of both CO₂ and H₂S increases but with a larger rate of increase for CO₂ For selective H₂S removal, it is preferable to operate at low liquid and high gas flow rates, low temperatures and low DIPA concentrations.     

甲醇蒸汽转化制氢和二氧化碳技术

针对中、小规模需氢用户的增加，介绍了甲醇蒸汽转化配变压吸附分离制氢新技术的工艺原理和技术特点；分别对工艺原料、动力消耗、环保达标情况进行了阐述。结果表明，该工艺在制得99，99％氢气的同时，还可以得到食品级二氧化碳。     

苯酚和二氧化碳合成碳酸二苯酯的热力学分析

根据经典热力学原理,计算了苯酚和二氧化碳合成碳酸二苯酯的反应在不同温度下的摩尔吉布斯自由能变化。结果表明,高温有利于碳酸二苯酯的生成;提高二氧化碳压力对平衡有利;计算结果与实验数据吻合,但实验收率偏低。     

压力对CH_4/CO_2重整制取合成气反应性能的影响

以 Ni/CeO_2-Al_2O_3为催化剂,考察了压力对 CH_4/CO_2重整反应的影响。实验结果表明,提高反应压力不仅使甲烷和二氧化碳的转化率降低,并由于积炭的加剧致使催化剂的失活速度加快。提高原料气中 CO_2与 CH_4摩尔比,气体空速,反应温度可以提高催化剂稳定性,减缓催化剂的失括速度。向反应体系中加入消碳能力强的 O_2同样可以提高催化剂稳定性。