溶胶-凝胶法制备MoP/SiO_2催化剂及其加氢脱硫催化活性的研究

以正硅酸乙酯为硅源,以钼酸铵和磷酸二氢铵为钼源和磷源,采用溶胶-凝胶法,经干燥、焙烧处理后,程序升温还原制备得到二氧化硅负载磷化钼(MOP)催化剂,并以二苯并噻吩为模型化合物,对催化剂的加氢脱硫活性进行初步评价,考察了负载量、反应压力、反应温度等因素对催化活性的影响.结果表明,溶胶-凝胶法制备负载催化剂最佳磷化钼负载量为20%(质量分数);升高反应压力和温度均有利于提高二苯并噻吩的转化率,但降低了产物中联苯的含量.     

碳化钼催化剂的制备及噻吩加氢脱硫性能

以MoO₃为前躯体,CH₄/H₂为还原碳化气,采用自制的程序升温还原碳化反应装置制备出Mo₂C催化剂,并用XRD、BET进行表征.借助原位TG-DTA方法研究了MoO₃在CH₄/H₂气氛中的还原碳化历程和适宜的还原碳化温度.以噻吩/环己烷溶液为模型反应物,采用高压微反-色谱实验装置考察了制备的碳化钼催化剂的噻吩加氢脱硫反应性能.结果表明：程序升温条件下的局部规整反应可提高催化剂的比表面积,且制备的碳化钼催化剂具有较高的噻吩加氢脱硫反应活性,在体积分数为5%的噻吩/环己烷溶液中,反应压力为3.0 MPa,空速为6 h^-1,H₂/原料液体积比500∶1的反应条件下, 370℃时的噻吩转化率达到98%以上,明显高于相应的硫化钼催化剂.还原碳化终温的提高,导致碳化钼催化剂比表面积的减少和表面积炭的增多,进而使其加氢脱硫反应活性降低.MoO₃在CH₄/H₂气氛中的还原碳化历程应为MoO₃→MoO₂→MoO_xC_y→Mo₂C,实验确定的适宜还原碳化温度为675℃.     

炭气凝胶的常压干燥制备研究

实验以间苯二酚(Resorcinol,简称R)与甲醛(Formaldehyde,简称F)以一定的摩尔比混合,加入二次去离子水作为溶剂并用碱性试剂作为催化剂,在恒温水浴中生成RF湿凝胶。在常温下用丙酮浸泡湿凝胶以置换水,制备出RF凝胶。最后将RF气凝胶置于管式炉中,在氮气保护气氛下,高温炭化得到炭气凝胶,并用TG-DTA,XRD、高倍显微镜等方法对其表面形貌及结构进行分析。     

氮化钼加氢脱硫催化剂研究进展

论述了高比表面积的γ-Mo2N的制备方法,阐述了γ-Mo2N的生成机理,讨论了原料气空速、升温速率、氮化温度和恒温时间对γ-Mo2N结构及其加氢脱硫活性的影响,以及不同的后处理方法、载体和助催化活性组分对γ-Mo2N的加氢脱硫活性的影响。     

钼基加氢脱硫催化剂的制备及应用研究进展

以钼在加氢脱硫(HDS)中的应用为线索,按催化剂结构不同,简介了负载型催化剂和非负载型催化剂的制备方法,总结了钼基加氢脱硫催化剂的应用进展。对于负载型钼基催化剂,按照载体不同,从单一氧化物载体、复合氧化物载体、分子筛载体和碳材料载体角度总结了催化剂在加氢脱硫中的应用。负载型催化剂虽然应用广泛,但其活性组分受载体限制。而非负载型催化剂可以有效提高活性组分含量,具有更高的催化活性。按照催化剂组成不同,总结了近年来单金属型、双金属型和多金属型非负载型催化剂在加氢脱硫中的应用。     

第二代常压渣油加氢脱硫催化剂的开发研制

随着市场对轻质油品的需求量上升和环保法规的日趋严格，全世界都更加关注渣油的轻质化技术。第二代常压渣油加氢脱硫催化剂采用挤条成型技术，活性组分以浸渍或完全混捏的方式加入，使催化剂成本大幅度降低，同时使最终催化剂具有高孔容、高比表面和适中堆密度，与第一代催化剂相比，活性和稳定性更好。     

钼基加氢脱硫催化剂的制备及应用研究进展

以钼在加氢脱硫(HDS)中的应用为线索,按催化剂结构不同,简介了负载型催化剂和非负载型催化剂的制备方法,总结了钼基加氢脱硫催化剂的应用进展。对于负载型钼基催化剂,按照载体不同,从单一氧化物载体、复合氧化物载体、分子筛载体和碳材料载体角度总结了催化剂在加氢脱硫中的应用。负载型催化剂虽然应用广泛,但其活性组分受载体限制。而非负载型催化剂可以有效提高活性组分含量,具有更高的催化活性。按照催化剂组成不同,总结了近年来单金属型、双金属型和多金属型非负载型催化剂在加氢脱硫中的应用。     

氮化钼深度加氢脱硫催化剂研究进展

介绍了γ-Mo2 N的制备方法 ,包括原料气空速、升温速率、氮化温度和恒温时间对γ-Mo2 N结构及其加氢脱硫活性的影响 ,以及不同的后处理方法和载体对γ-Mo2 N的加氢脱硫活性的影响。阐述了其作为加氢脱硫催化剂的作用机理 ,助催化组分的加入对其催化加氢反应的影响 ,并提出了其实现产业化所应解决的问题     

我厂钴钼加氢—氧化锌脱硫简介

我厂于六十年代从英国ICI公司引进的10万吨/年合成氨装置,采用MEA(一乙醇胺)、碱洗、活性炭吸附等三级脱硫。原设计脱硫后天然气含硫≤3ppm,但生产中按此工艺指标运行,造成一段炉催化剂中毒,转化管局部过热烧坏。1972年,汉格公司建议将脱硫后天然气含硫指标改为<0.5ppm,并采用氧化锌脱硫。     

常压栲胶脱硫存在的问题及改造措施

1　常压脱硫系统运行状况我公司制氢装置设计为公司精苯、环己醇和己二胺三套装置提供 99 9%的纯氢 ,采用湿法栲胶脱硫 ,其常压脱硫塔为 2 60 0× 32 30 2mm的填料塔 ,聚丙烯阶梯环分三层装填 ,填料总高1 9 5m ,操作温度 40℃ ,操作压力 0 1MPa。该制氢装置自 1 998年 8月投产以来 ,常脱塔处理气量一般在 1 40 0 0m3/h左右 ,溶液循环量控制在 330m3/h ,进口H2 S含量在 1 0 g/L左右 ,出口H2 S含量在 5 0～ 1 0 0mg/L ,远远低于出口H2 S含量 <30mg/L的工艺指标要求。但经过两年的运行 ,脱硫系统也暴露出如下一些问题。1 1　碱耗高…     

3,4-二甲基苯甲醛的常压法合成及表征

以邻二甲苯、CO和HCl为原料,以AlCl3为催化剂,经过Gattermann-Koch反应,在常压下合成3,4-二甲基苯甲醛,反应的较佳条件是:n(邻二甲苯)∶n(AlCl3)=1∶1.1,反应温度0⁵℃,反应时间12 h。在此条件下,3,4-二甲基苯甲醛收率约为61%,纯度为98.9%。     

Preparation of highly active MCM-41 supported Ni2P catalysts and its dibenzothiophene HDS performance

Highly active MCM-41 supported nickel phosphide catalysts for hydrodesulfurization(HDS) were synthesized by two different phosphorus sources, in which the surface of Ni_2P catalysts were modified by air instead of being passivated by O_2/N_2 mixture. In addition, the catalysts need not be activated with flowing H_2(30 ml·min~(-1))at 500 °C for 2 h prior to reaction as traditional method. X-ray diffraction(XRD), X-ray photoelectron spectroscopy(XPS), N_2-adsorption specific surface area measurements and CO chemisorption were used to characterize the resulting catalysts. The effect of modification with air on the surface of the catalysts for HDS performance was investigated. Results showed that the surface modification with air can promote the formation of smaller Ni_2P particles and more active Ni sites on surface of catalysts. At 3.0 MPa and 613 K, the dibenzothiophene(DBT)conversion of the catalysts modified with air was 98.7%, which was 7.1% higher than that of catalyst passivated by O_2/N_2 mixture. The higher activities of Ni_2P(x)/M41-O catalysts can be attributed to the smaller Ni_2P particles sizes and the increased hydrogen dissociation activity due to the surface modification.     

Study on wettability improvement and its uniformity of wool fabric treated by atmospheric pressure plasma jet

The influence of processing parameters on wettability improvement and its uniformity of wool fabric treated by atmospheric pressure plasma jet (APPJ) was explored. A woven wool fabric was treated by APPJ under various treatment conditions such as different treatment time, different oxygen flow rate, and different jet‐to‐substrate distance. The water absorption time of wool fabric was measured to determine wettability improvement. The diffusion photo of water droplet on wool fabric surface was taken by digital camera to reflect wettability uniformity. After APPJ treatment, SEM observation showed that the scales on the wool fiber surface directly facing plasma jet pores were destroyed than those on the other fiber surface. XPS analysis showed that the carbon concentration substantially decreased. The concentration of oxygen and nitrogen significantly increased and but the concentration of sulfur and silicon did not obviously changed. With the addition of oxygen gas, more polar groups such as hydroxyl and carboxyl produced on wool fiber surface. The water absorption time of wool fabric greatly reduced indicating wettability improvement. The diffusion of water droplet on wool fabric surface was also larger and more homogenous suggesting uniform plasma treatment. It was concluded that the wettability improvement and its uniformity of the treated wool fabric increased and then decreased with the increasing oxygen flow rate and jet‐to‐substrate distance, and increased with the increasing treatment time. Therefore to achieve reasonable wettability and its uniformity of the wool fabric treated by APPJ, plasma treatment conditions have to be carefully chosen. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011     

Structural properties and HDS activity of NiMo catalysts supported on lanthana modified zeolite type X and Y

In the search for the active catalysts of hydrodesulfurization reaction, an attempt was made to use zeolites as supports. A series of NaLaX, Mo/NaLaX and NiMo/NaLaX as well as NaLaY, Mo/NaLaY and NiMo/NaLaY catalysts was prepared and their performance in this reaction was studied. It was shown that crystalline structure of the lanthana forms of the above zeolites only little collapsed after ion-exchange and impregnation with active Mo and NiMo components. The NiMo catalysts supported on the zeolites studied were found active in thiophene hydrodesulfurization. The catalysts with lanthana after the first step of ion exchange were the most active.     

TiO2复合氧化物的制备及其在加氢脱硫中的应用

对TiO₂、TiO₂-Al₂O₃、TiO₂-SiO₂和TiO₂-ZrO₂载体的制备技术及其在加氢脱硫中的应用进行了综述。研究表明，以TiO₂调变的Al₂O₃、SiO₂和ZrO₂载体能影响MoO₃与Al₂O₃、MoO₃与SiO₂及MoO₃与ZrO₂之间的相互作用，改善MoO₃在载体表面的分散，促进其还原，有利于提高催化剂表面活性组分的数量，提高催化剂的加氢脱硫活性。     

常压法制备3，3，3－三氟丙酮酸乙酯

常压制备法具有反应温度易于控制、副反应少、得率高的优点。     

常压等离子体处理芳砜纶的结构与性能研究

分别采用氦气和氦气/氧气对芳砜纶进行常压等离子体处理。采用滴水吸收实验测定处理前后纤维表面的润湿性,利用扫描电子显微镜和X射线光电子能谱仪分析处理前后纤维表面形态和化学成分的变化。结果表明:经常压等离子体处理后芳砜纶表面粗糙度增加,纤维表面碳元素含量下降,羟基、羧基等含氧或氮的极性基团增加,芳砜纶纱线的润湿性能提高,纱线强度没有明显变化,氦气/氧气等离子体处理比氦气等离子体处理效果更好。     

竹屑常压酸催化液化产物的制备与表征

在常压酸催化作用下对竹屑进行多元醇液化,对液化产物的羟值和粘度进行了测定,并通过红外光谱、凝胶渗透色谱及GC-MS等对液化产物进行分析表征。结果表明:液化产物的羟值为350mgKOH/g,粘度为750mPa·s,相对分子质量分布范围在18~20 372之间,为连续分布形式,满足制备中强度硬质聚氨酯泡沫的要求。