CATALYTIC UPGRADING OF USED LUBRICATING OILS

ABSTRACT

Several commercial catalysts were tested for their activity for upgrading waste lubricating oils. The feedstock was vacuum distilled to remove the light and the heavy ends. Two trickle-bed reactors placed in series were employed, the top reactor contained a high surface area alumina and the bottom reactor the catalyst. A Ni-Mo-AI₂O₃ catalyst was selected for further study on the basis of its higner activity and activity maintenance. Several different hydrogen pressures, reactor temperatures, and liquid volume hourly space velocities were employed to arrive at the most optimum process conditions. This paper will discuss the effect of catalyst and process conditions on the product liquid color, viscosity, nitrogen, and sulfur content.     

Aromatization of FCC Gasoline Over Modified HZSM-5 Catalyst

Zinc and phosphorus incorporated HZSM-5 catalyst was prepared by adopting incipient wet co-impregnation (Zn-P/HZSM-5). Zn-P/HZSM-5 catalyst exhibited the lowest acidity but the highest aromatization activity with stable performance in the studied period of 16 hr. The process conditions on aromatization reaction and the coke deactivation mechanism of Zn-P/HZSM-5 catalyst were studied on a small-scale, fixed bed reactor using FCC naphtha (75-120°C). The weight contents of ZnO and P₂O₅ were 2% and 4%, respectively. Results showed that Zn-P/HZSM-5 catalyst under a temperature of 450°C, liquid hourly space velocity of 1.0 h^-1, and pressure of 0.1 MPa, the conversions of olefins and alkanes are 96.77% and 88.94%, respectively, the contents of olefins, aromatics in liquid product are 6.79% and 74.57%, respectively. Carbon deposition was the major reason for catalyst deactivation due to the catalyst's good performance as a fresh catalyst after regeneration. All of the blending products fitted the standards of Chinese gasoline.     

Performance Evaluation of Certain Commercial Hydrotreating Catalysts in a Pilot Plant Reactor

The performance of different hydrotreating catalysts was evaluated in a pilot plant trickle bed reactor using a feedstock collected from an industrial diesel hydrodesulfurization unit. The feed is a typical blend of straight run diesel fractions from crude distillation units, FCC cycle oils, heavy naphtha, etc. It contains 1.11 wt% of sulfur, 0.12 wt% of nitrogen, and 34.6 wt% of total aromatics. The catalyst samples evaluated in the present work are commercially available high activity new generation catalysts being used in many refineries for diesel hydrodesulfurization application. The experiments were carried out at a constant pressure of 40 kg/cm² and a constant H₂/oil ratio of 200 l/l. Experiments were performed to study the influence of reactor temperature and liquid hourly space velocity on product quality. The reactor temperature was varied from 320-360°C at different liquid hourly space velocities. The liquid hourly space velocity was varied from 1.0 to 2.5 h^-1 at different reactor temperatures. The feed and product samples hydrotreated in the pilot plant reactor were analyzed to determine their physical properties and measure sulfur, nitrogen, olefinic, poly-, di-, monoaromatic, and naphthenic hydrocarbons. Catalyst C was found to have the highest hydrodesulfurization activity among the catalysts studied. The hydrodesulfurization activity of catalyst A and catalyst B are similar. Catalyst D was found to have lower hydrodesulfurization and higher hydrodenitrogenation activity compared to catalyst C.     

基于响应曲面法的环管装置聚丙烯相对分子质量的模拟及优化

基于响应曲面法（RSM）,采用5因素3水平的Box-Behnken设计,通过Aspen Polymers Plus软件模拟了环管式丙烯聚合过程,探讨了聚合温度、压力、丙烯质量流量、催化剂用量、H₂体积分数对环管反应器出口聚丙烯(PP)相对分子质量的影响,建立了以环管反应器出口PP相对分子质量为响应函数的数学模型,对聚合反应条件进行了优化,确定了满足PP相对分子质量为(1.22±0.004)×10.5的最佳操作条件。结果表明,在聚合温度71.1℃、压力3.25 MPa、丙烯质量流量671×10.3 kg/h、催化剂用量0.20 kg/h、H₂体积分数3.12%的最佳操作条件下,得到的PP相对分子质量为1.22075×10.5,与目标值的偏差仅为0.061%;采用响应面法优化环管装置生产具有目标相对分子质量PP的操作条件可行,建立的数学模型能够较准确地预测PP相对分子质量,可以用于指导工业生产。     

IN-SITU ACTIVATION OF METHANOL SYNTHESIS CATALYST IN A THREE-PHASE SLURRY REACTOR

In the liquid phase methanol synthesis process, syngas reacts in the presence.of fine catalyst particles slurried in the oil phase, in a three phase slurry reactor system. A method for activating high concentration ( ≤25 wt. %) of the CuO-ZnO-Al₂O₃ catalyst in the catalyst-oil slurry has been successfully developed. This catalyst activation process can be of crucial significance in the research and development of the methanol synthesis process in a liquid entrained reactor.

The reducing gas contains 2% hydrogen in nitrogen mixture and this activation procedure is carried out at a pressure of 125 psi. The catalyst-oil slurry is subjected to a controlled temperature ramping from 110° to 250° C. The catalyst has beemshown to be effectively reduced after following this activation procedure, that is valid especially for high catalyst loadings in slurry. Since the reduction is carried out in the process liquid medium and inside the reactor system, the catalyst-oil slurry after the treatment is ready for the synthesis of methanol.     

三乙胺基SO3H-功能化离子液体催化合成己二酸二丁酯

以三乙胺为主要原料合成了5种BrØnsted酸性离子液体,考察了不同结构离子液体对合成己二酸二丁酯的催化活性,并将离子液体酸性强弱与酸催化活性进行关联,同时优化反应温度、原料配比、反应时间、催化剂用量等反应条件。结果表明,以N (4 磺酸基)丁基三乙胺硫酸氢盐离子液体为催化剂,添加带水剂环己烷,在反应温度110℃、n(1 Butanol)/n(Adipic acid)=6、m(Catalyst)/m(Adipic acid)=001、m(Cyclohexane)/m(Raw materials)=015、反应时间3 h的条件下,己二酸转化率达到99%;经连续重复使用7次,该催化剂仍可保持很高的催化活性。     

Etherification Performance of Transition Metals Modified β-Zeolite Catalyst

The etherification experiment for FCC light gasoline on transition metals modified Hβ zeolite was studied in a fixed-bed reactor. The effect of preparation condition of catalyst on the catalyst's activity, stability, and the effect of reaction temperature, methanol/tert-olefin molar ratio, and liquid hour space velocity on the etherification reaction were discussed. The experimental results showed that the different metals modified Hβ zeolite had different etherification performances. And the conversion of tertiary carbon-olefins of the molybdenum modified Hβ zeolite, which was loaded 3%, was higher 6.0% than the Hβ zeolite. The optimal reaction conditions were temperature 70-80°C, liquid hour space velocity 1.0 h^-1 and methanol/tert-olefin molar ratio 1.05. The modified Hβ zeolite catalysts possessed favorable prospect for its higher stability.     

HYDROPROCESSING OF COAL-DERIVED MIDDLE DISTILLATE

Coal-derived middle distillate, boiling range 437 to 623^°K, was hydrotreated in a fixed bed reactor with a commercial N_iO-M_o0₃/ Al₂O₃ catalyst. The feedstock contained predominantly highly-substituted aromatics. The product heteroatom content and aromaticity decreased with increased process temperature or pressure. Aromaticity was proportional to liquid space velocity. Heteroatonms could be effectively reduced at hydroprocessing conditions of 653^°K, 10 MPa, and 2 WHSV. Experimentally-derived cetane number was found to be proportional to product aromaticity. Severe hydroprocessing conditions were required to produce diesel fuel of acceptable cetane number.     

钾基复合催化剂对高硫石油焦气化性能的影响

以高硫石油焦为研究对象,探讨了水蒸气气氛下不同钾基催化剂、铁基催化剂以及K-Fe、K-Ca复合催化剂对高硫石油焦气化性能的影响。在1023 K、0.1 MPa下,钾基催化剂中KOH催化活性最高,而铁基催化剂中FeSO₄催化活性最高;在KOH基础上添加铁基催化剂后其催化性能有所降低;在K-Ca复合催化剂中,5%KOH和3%CaO(质量分数)复配时,催化剂的催化性能最好,石油焦碳转化率达到最高值61.33%,继续增加CaO添加量,K-Ca复合催化剂的催化性能降低。采用BET和XRD对K-Ca复合催化剂的催化作用机理进行研究,发现CaO的造孔作用以及石油焦气化反应过程中生成的双金属碳酸盐K₂Ca(CO₃)₂共同促进了气化反应的进行。而在压力增大的条件下,由于K-Ca复合催化剂中双金属碳酸盐K₂Ca(CO₃)₂的晶型发生转变,导致其催化活性相比添加KOH催化剂时降低。     

THE ROLE OF WATER IN METHANOL SYNTHESIS

This work focuses on the influence of water in determining the rate of methanol synthesis over CuO/ZnO/Al₂O₃ catalysts. The experimental investigations were conducted in a 1-L slurry reactor based on the novel liquid phase methanol synthesis process. The liquid medium used was a blend of paraffinic and naphthenic mineral oils with a mean molecular mass of 250. It was found that the methanol rates attained a maximum at an optimal water content which was dependent on the reaction temperature. The catalytic activity was found to decline with time at lower temperatures in the presence of a relatively large excess of water. The influence of water was also found to be firmly linked to the corresponding carbon dioxide content in the reactor feed. The experimental data bear additional significance because this was the first such study to be performed on the liquid phase process. Emphasis was therefore placed on the use of a CO-rich syngas in order to simulate anticipated process conditions.