二段多产丙烯试验轻汽油转化不充分的原因

在重油二段提升管催化裂解多产丙烯(TMP)技术中,回炼富含烯烃的轻汽油可进一步增产丙烯。实验室研究表明,回炼占新鲜原料19%的轻汽油,丙烯收率即可增加5%以上,而干气增加不到1%。而在工业试验中回炼占新鲜原料21.88%的轻汽油对丙烯和干气的贡献分别为1.51%和1.37%。其原因在于回炼的轻汽油高速喷入本身造成的催化剂稀相区和重油进料造成的催化剂稀相区,导致以分子形式分散的轻汽油与催化剂不能充分接触、吸附和发生催化转化,并因催化剂流化密度低而不能及时终止未能吸附的轻汽油分子发生热裂化反应,因而丙烯的贡献低而对干气的贡献高。     

Preparation of bio-fuels by catalytic cracking reaction of vegetable oil sludge

Biofuel production from vegetable oil is potentially a good alternative to conventional fossil derived fuels. Moreover, liquid biofuel offers many environmental benefits since it is free from nitrogen and sulfur compounds. Biofuel can be obtained from biomass (e.g. pyrolysis, gasification) and agricultural sources such as vegetable oil, vegetable oil sludge, rubber seed oil, and soybean oil. One of the most promising sources of biofuel is vegetable oil sludge. This waste is a major byproduct of vegetable oil factories. It consists of triglycerides (61%), free fatty acid (37%) and impurities (2%). The hydrocarbon chains of triglycerides and free fatty acid are mainly made up of C₁₆ (30%) and C₁₈ (36%) hydrocarbons. The others consist of C₁₂-C₁₇ hydrocarbon chains. Transesterification can help in converting vegetable oil sludge into biofuel. The disadvantage of this method is that a large amount of methanol is required. The alternative method for this conversion is catalytic cracking. The objective of this research is to evaluate and compare the pyrolysis process with cracking catalytic reaction of vegetable oil sludge by Micro-activity test MAT 5000 of Zeton-Canada.A ZSM-5/MCM-41 multiporous composite (MC-ZSM-5/MCM-41), was successfully synthesized using silica source extracted from rice husk. The material has the MCM-41 mesoporous structure, and its wall is constructed by ZSM-5 nanozeolite crystals. The porous system of the material includes pores of the following sizes: 5 Å (ZSM-5 zeolite), 40 Å (MCM-41 mesoporous material), and another porous system whose diameter is in the range of 100-500 Å (mesoporous system) formed by the burning of organic compounds that remain in the material during the calcination process. This pore system contributes to an increase in the catalytic performance of synthesized material.The results of vegetable oil sludge cracking reaction show that the product consists of fractions such as dry gas, liquefied petroleum gas (LPG), gasoline, light cycle oil (LCO), and (heavy cycle oil) HCO, which are similar to those of petroleum cracking process.MC-ZSM-5/MCM-41 catalyst is efficient in the catalytic cracking reaction of vegetable oil sludge as it has higher conversion and selectivity for LPG and gasoline products in comparison to the pyrolysis process. Product distribution (% of oil feed) of cracking reaction over MC-ZSM-5/MCM-41 is coke (3.4), total dry gas (7.0), LPG (31.1), gasoline (42.4), LCO (8.9), HCO (7.2); and that of pyrolysis are coke (19.0), total dry gas (9.3), LPG (16.9), gasoline (28.8), LCO (13.7), and HCO (12.3).These results have indicated a new way to use agricultural waste such as rice husk for the production of promising catalysts and the processing of vegetable oil sludge to obtain biofuel.     

甘油三酯热解法生产可再生性燃料和化学品研究进展

对主要由甘油三酯组成的植物油和动物脂肪进行热分解,结果显示此法可用来生产可再生性燃料和化学品。主要探讨甘油三酯基质的热化学转化问题,热化学转化主要分为两类:(1)直接热分解;(2)加热和催化的联合裂解。所用的主要催化剂为:过渡金属催化剂、分子筛催化剂、活性铝土和无水碳酸钠等4类。反应产物很大程度上取决于催化剂的种类和反应条件,通常既含有柴油类馏分,也含有汽油类馏分。     

COKC-1催化剂在催化裂化装置的工业应用

介绍中国石化催化剂有限公司齐鲁分公司COKC-1催化剂在中国石化武汉分公司二套催化裂化装置的工业应用情况。结果表明,与对比催化剂相比,在平衡剂重金属含量增加情况下,COKC-1催化剂表现出优良的抗重金属能力和水热稳定性;使用COKC-1催化剂后,汽油产率增加6.68个百分点,汽油产率达到51.28%,液化气和汽油总产率增加2.73个百分点,油浆、干气和柴油产率下降。     

催化裂化提升管反应器中颗粒聚团裂化反应的数值模拟

Behavior of catalytic cracking reactions of particle cluster in fluid catalytic cracking (FCC) riser reactors was numerically analyzed using a four-lump mathematical model. Effects of the cluster porosity, inlet gas velocity and temperature, and coke deposition on cracking reactions of the cluster were investigated. Distributions of temperature, gases, and gasoline from both catalyst particle cluster and an isolated catalyst particle are presented. The reaction rates from vacuum gas oil (VGO) to gasoline, gas and coke of individual particle in the cluster are higher than those of the isolated particle, but it reverses for the reaction rates from gasoline to gas and coke. Less gasoline is produced by particle clustering. Simulated results show that the produced mass fluxes of gas and gasoline increase with the operating temperature and molar concentration of VGO, and decrease due to the formation of coke.     

重质原料油生产轻烯烃的Ⅱ型催化裂解工艺和催化剂

Ⅱ型催化裂解是以重质油为原料生产丙烯、异丁烯和异戊烯等轻烯烃, 并同时兼产高辛烷值优质汽油的新催化工艺。该工艺使用新研制的新型择形催化剂, 可以加工减压馏分油、减压馏分油掺渣油或二次加工油以及全常压渣油, 并成功地进行了工业化试验。以临胜减压馏分油掺左右脱沥青油为原料, 可以得到12.52wt%~14.43wt%的丙烯和11.23wt%~11.41wt%的丁烯,同时还得到40wt%左右93号优质汽油。型催化裂解工艺开创了一条以重质油为原料生产轻烯烃和高辛烷值优质汽油的新途径     

Catalytic behaviour of nickel and iron metal contaminants of an FCC catalyst after oxidative and reductive thermal treatments

The catalytic effects of nickel and iron deposited on an FCC (fluidized catalytic cracking) catalyst via metal naphthenates were studied in a micro activity test (MAT) unit after both oxidative and reductive treatments of the catalyst samples.The dehydrogenation activity of nickel was found to be close to the dehydrogenation activity of vanadium – and not several times higher than that of vanadium as is often reported – when deposited on the commercial FCC catalyst used in this study followed by steam deactivation (oxidative treatment) at 760 °C. However, the dehydrogenation activity of nickel was significantly intensified after post-treatment with a CO/N₂ mixture at this temperature (reductive treatment).The results show that iron did not have a dehydrogenation activity after steaming, but had a significant dehydrogenation activity after steaming when followed by exposure to the CO/N₂ mixture at 760 °C. The results indicate that the presence of deposited iron was inducing an additional catalytic cracking activity for the FCC catalyst.It was observed that co-impregnation of equal loadings of nickel, iron and vanadium on the FCC catalyst led to a considerably higher dehydrogenation activity than could be expected from the catalytic behaviour of the separate elements. The dehydrogenation activity was however slightly reduced by the reductive treatment as the reduced dehydrogenation activity from the lower oxidation state of vanadium (V³⁺) more than compensated the increased dehydrogenation activity of iron and nickel. A slightly increased gasoline production after the reductive treatment of the co-impregnated sample was a result of the increased production of gasoline from the FCC catalyst itself, which more than compensated for the reduced gasoline production from nickel.     

Four-lump kinetic model for fluid catalytic cracking process

In the fluid catalytic cracking reactor heavy gas oil is cracked into more valuable lighter hydrocarbon products. The reactor input is a mixture of hydrocarbons which makes the reaction kinetics very complicated due to the involved reactions. In this paper, a four-lump model is proposed to describe the process. This model is different from others mainly in that the deposition rate of coke on catalyst can be predicted from gas oil conversion and isolated from the C₁–C₄ gas yield. This is important since coke supplies heat required for endothermic reactions occurring in the reactor. By this model we can also conclude that the C1–C4 gas yield increases with increasing reactor temperature, while production of gasoline and coke decreases.     

TMP工艺与催化剂的配套性分析

在重油催化裂解多产丙烯（简称TMP）技术中,将两段催化裂解工艺与配套的增产丙烯催化剩结合,以大庆常压渣油为原料可以得到20％的丙烯收率,并能够很好兼顾汽柴油的质量。试验结果表明：以大庆常压渣油为原料,使用配套开发的LCC-300催化剂,干气加焦炭收率。小于15％、丙烯的收率大于20％、汽油的辛烷值RON96、烯烃30％（v）左右。     

混合废塑料裂解液相产物的分析

通过SH/T 0558色谱模拟蒸馏技术和成分检测分析混合废塑料裂解得到的液相产物。详细介绍了SH/T 0558色谱模拟蒸馏技术快速测定裂解油馏程的方法,采用nC_9、nC_(10)混合物作为裂解油模拟蒸馏的内标物,使用常规峰面积归一分析方法,经过处理产生色谱模拟蒸馏的测定报告。该方法样品用量少,操作简便,分析速度快,结果精确,最大相对标准偏差为0.75%,能够较好的模拟裂解油馏程。混合废塑料热裂解和催化裂解得到的液相产物中汽油和柴油的含量较高,油品质量较好。对混合废塑料热裂解和催化裂解所获得的两种油样进行饱和烃、芳烃和烯烃成分检测,有催化剂参与后烯烃+芳烃的总量为85.2%,其汽油辛烷值很高,可作为高标号优质汽油组分。     

从ACE评价数据看高液收低焦炭型FCC催化剂的设计

从大量ACE评价数据入手,研究了重油转化率、油浆收率和焦炭之间的相互关系,反应产物柴油、干气与焦炭的关系,热裂化与催化裂化比值、氢转移指数与焦炭的关系。结果表明,在低焦炭产率的同时要获得高的总液收(汽油+柴油+液化气),应结合装置特点合理控制重油转化率,并以碳氢比低的柴油作为催化裂化的主要目标产品,同时降低反应过程中的热裂化反应和氢转移反应。对这些规律进行了深入分析,并提出了具体的高液收低焦炭催化裂化催化剂的设计思路。     

催化裂化装置回炼加氢石脑油对产品的影响

加氢石脑油作为催化裂化装置急冷油进入提升管进行回炼,对回炼加氢石脑油期间产品分布和产品性质有较为明显的影响。干气、液化气和柴油收率明显下降,汽油收率明显升高,汽油辛烷值和芳烃含量也呈下降趋势,稳定汽油有效烯烃含量明显降低,对醚化反应操作有较大的影响。通过分析催化裂化装置回炼加氢石脑油对产品分布和产品性质的影响,为未来生产调整提供数据参考。     

A novel conceptional process for residue catalytic cracking and gasoline reformation dual-reactions mutual control

Based on the subsidiary riser FCC (SRFCC) process for gasoline reformation [Y.H. Bai, J.S. Gao, S.C. Li, C.M. Xu, Petrol. Process. Petrochem. (China) 35 (2004) 17–21, J.S. Gao, C.M. Xu, Y. Mao, et al., Petrol. Refin. Eng. (China) 35 (2005) 7–9], a novel conceptional process for residue catalytic cracking and gasoline reformation dual-reactions mutual control (DMC) was proposed and relevant experimental researches were carried out in a Technical Pilot Scale Riser (TPSR) FCC apparatus. The goals of DMC were to improve product quality and increase desirable product yield in residue catalytic cracking as well as in FCC gasoline upgrading. The experiments showed that the decrease of temperature difference between feedstock and regenerated catalysts in DMC by directly leading the cooled regenerated catalysts into riser reactor or feeding gasoline into riser reactor in vapor phase could decrease the amount of dry gas and coke and obtain a better quality of upgraded gasoline. Moreover, the spent catalysts still retaining high level of activity could be recycled to the base of the main riser reactor treating heavy oil and mixed with regenerated catalysts in DMC, it allows residue catalytic cracking to operate at high catalyst-to-oil ratio and the relatively low inlet catalysts temperature. The experimental results also showed that the mixed catalysts could improve the product selectivity in residue catalytic cracking, especially for light oil (gasoline and diesel). In addition, compared with the routine RFCC, the product distribution from the residue catalytic cracking in DMC contains more liquid products, less dry gas, and a better gasoline quality.     

Enhancing propylene production from catalytic cracking of Arabian Light VGO over novel zeolites as FCC catalyst additives

The catalytic cracking of vacuum gas oil over fluid catalytic cracking (FCC) catalyst containing novel additives was investigated to enhance propylene yield. A conventional ZSM-5, mesoporous ZSM-5 (Meso-Z), TNU-9 and SSZ-33 zeolite were tested as additives to a commercial equilibrium USY FCC catalyst (E-Cat). Their catalytic performance was assessed in a fixed-bed micro-activity test unit (MAT) at 520 °C and various catalyst/oil ratios. The cracking activity of all E-Cat/additives did not decrease by using these additives. The highest propylene yield of 12.2 wt.% was achieved over E-Cat/Meso-Z compared with 9.0 wt.% each over E-Cat/ZSM-5 and E-Cat/TNU-9, at similar gasoline yield penalty. The enhanced production of propylene over Meso-Z is attributed to its mesopores that suppressed secondary and hydrogen transfer reactions and offered easier transport and accessibility to active sites. The lower enhancement of propylene over the large-pore SSZ-33 additive was due to its high-hydrogen transfer activity. Gasoline quality was improved by the use of all additives, as octane rating increased by 7-12 numbers for all E-Cat/additives.     

The Thermocatalytic Cracking Process for the Production of Light Olefins and Transportation Fuels from Gas Oils

The thermocatalytic cracking (TCC) process, which can selectively produce light olefins (mostly, ethylene and propylene for the petrochemical industry) and transportation fuels (gasoline and diesel fuel), combines the effects of thermal and catalytic cracking reactions. The TCC catalysts consist mainly of mixed metal oxides supported on a high-surface area – thermally stabilized alumina. The best TCC catalyst formulation includes a co-catalyst, which provides the main catalyst component with active hydrogen species formed from hydrogen and other hydrocarbons, particularly methane, produced mainly by thermal cracking. The interparticular interactions of these hydrogen spilt-over species can occur because these species can be easily transferred from one particle to the other through the newly formed pore connections     

劣质原料催化裂化脱硫降烯烃生产清洁汽油技术

介绍了劣质催化裂化原料的特点,分析了催化裂化汽油清洁化对策,应从提高FCC汽油质量关键应从FCC进料预处理、优化FCC加工过程以及FCC汽油精制等3方面出发．采用有效的降烯烃技术以及选择性加氢和氧化一萃取等脱硫技术对催化裂化汽油进行清洁化处理。认为应注重发展加氢技术,增强加氢在清洁油品生产中的作用;适当减少FCC汽油所占比例,增加异构化油、烷基化油、重整汽油比例,缩小与国外成品油结构组成的差距。     

An unconventional cracking method for hydrocarbon compounds and their derivatives : 1. Liquefaction of polyolefins

Liquefaction of polypropylene, polyethylene and polystyrene by oxidative degradation with gas oil as a carrier and phenol as a catalyst was performed in an autoclave. Air pressure, temperature and reaction time were varied. The advantage of this process is the production of non-oxygenated lighter compounds, mainly saturated hydrocarbons, from the polyolefins. The optimum cracking conditions were 0.7 MPa air pressure, 400°C and 30 min reaction, yielding 32 wt% gasoline, 15 wt% kerosene and 27 wt% gas oil from the degraded oil of polypropylene. These products had petroleum-like properties according to ASTM and IP test methods. Furthermore the oils obtained can be used as chemical feedstocks. From the results, a reaction mechanism is proposed which postulates (1) thermal elimination of hydrogen atoms from hydrocarbon molecules via interaction between phenol and oxygen molecules (initial step), (2) degradation of the resulting hydrocarbon macroradicals through β-scission, producing relatively low-molecular-weight end-chain radicals and (3) free radical transfer reactions via phenoxy radicals, with steps (2) and (3) producing competitive acceleration of the hydrocarbon degradation in a random scission mechanism.     

催化裂化汽油降烯烃助剂的开发研究

基于催化裂化催化剂降烯烃方面的研究进展，在现有催化裂化金属钝化剂的基础上，围绕提高氢转移活性，提出制备降烯烃催化裂化助剂的技术路线，并研制开发了新型降烯烃催化裂化助剂。实验结果显示，降烯烃助剂不仅具有良好的抗重金属污染的特性，而且能有效地降低汽油中的烯烃含量，其具有较高的氢转移活性，可协调芳构化与氢转移反应，同时也改善了催化裂化产品分布。     

催化裂化轻汽油在ZSM-5分子筛催化剂上裂化反应的研究

以ZSM-5分子筛为催化剂，在小型固定床反应器上，进行了催化裂化轻汽油的裂化反应。考察了反应温度和空速对催化裂化轻汽油裂化反应气液相收率和产品分布的影响。实验结果表明，ZSM-5分子筛催化剂具有较强的裂化活性和氢转移活性。在保证裂化转化率的条件下，提高反应温度和空速可以抑制催化剂上氢转移反应的发生。以ZSM-5分子筛为催化剂上的催化裂化反应中，温度、空速是影响转化率和选择性的重要因素，因此可以通过改变温度、空速来提高目的产物的选择性。但是，单纯依靠改善反应条件，不能使目的产物的收率和选择性达到理想的程度，还必须对催化剂进行改性。ZSM-5分子筛催化剂上催化裂化反应的研究为ZSM-5分子筛催化剂的进一步改性，及ZSM-5分子筛催化剂在轻汽油催化裂解和汽油改质方面的进一步应用提供了试验依据。     

Effect of process conditions on the composition of products in the conventional and deep catalytic cracking of oil fractions

With the purpose of increasing the yield of light C₂-C₄ olefins in comparison with that in conventional catalytic cracking, we experimentally study the effect of temperature and catalyst-to-oil ratio on the distribution of the basic products of oil catalytic cracking on the bizeolite and industrial LUX catalysts. The bizeolite catalyst contains ZSM-5 and ultrastable Y zeolites in equivalent amounts, while the LUX catalyst contains 18 wt % of Y zeolite in the HRE form. As shown by the results of our tests, the yield of C₂-C₄ olefins and gasoline in the deep catalytic cracking of hydrotreated vacuum gasoil on the bizeolite catalyst within a range of catalyst-to-oil ratios of 5–7 and temperatures of 540–560°C reaches 32–36 and nearly 30 wt %, respectively. In cracking on the LUX catalyst under similar conditions, the yield of light olefins and gasoline is 12–16 and 37–45 wt %, respectively. The distribution of target products in the deep catalytic cracking of different hydrocarbon fractions (vacuum gasoil, gas condensate, its fraction distilled from the cut boiling below 216°C, and the hydrocracking heavy residue) on the bizeolite catalyst is studied. It is shown that the fractions of gas condensate and hydroc-racking residue can serve as an additional source of hydrocarbon raw materials in the production of olefins.