大庆常压催化裂解动力学研究

Catalytic pyrolysis of Daqing atmospheric residue on catalyst CEP-1 was investigated in a confined fluidized bed reactor. The results show that reaction temperature, the mass ratios of catalyst to oil and steam to oil have significant effects on product distribution and yields of light olefins. The yields of light olefins show the maxima with the increase of reaction temperature, the mass ratios of catalyst to oil and steam to oil, respectively. The optimized operating conditions were determined in the laboratory, and under that condition the yields of ethylene, propylene and total light olefins by mass were 15.9%, 20.7% and 44.3% respectively. The analysis of pyrolysis gas and pyrolysis liquid indicates that CEP-1 has good capacity of converting heavy oils into light olefins, and there is a large amount of aromatics in pyrolysis liquid.     

动植物油生产清洁燃料和低碳烯烃的替代加工工艺

Since the production cost of biodiesel is now the main hurdle limiting their applicability in some areas, catalytic cracking reactions represent an alternative route to utilization of vegetable oils and animal fats. Hence, catalytic transformation of oils and fats was carried out in a laboratory-scale two-stage riser fluid catalytic cracking （TSRFCC） unit in this work. The results show that oils and fats can be used as FCC feed singly or co-feeding with vacuum gas oil （VGO）, which can give high yield （by mass）of liquefied petroleum gas （LPG）, C2-C4 oletms, tor example 45% LPG, 47% C2-C4 olefins, and 77.6% total liquid yield produced with palm oil cracking. Co-feeding with VGO gives a high yield of LPG （39.1%） and propylene （18.1%）. And oxygen element content is very low （about 0.5%） in liquid products, hence, oxygen is removed in the form of H2O, CO and CO2. At the same time, high concentration of aromatics （C7-C9 aromatics predominantly） in the gasoline fraction is obtained after TSRFCC reaction of palm oil, as a result of large amount of hydrogen-transfer, cyclization and aromatization reactions, Additionally, most of properties of produced gasoline and diesel oil fuel meet the requirements of national standards, containing little sulfur. So TSRFCC technology is thought to be an alternative processing technology leading to production of clean fuels and light olefins.     

Pd/Fe对-二氯苯的催化脱氯及其动力学

o-Dichlorobenzene (o-DCB) was dechlorinated by Pd/Fe powder in water through catalytic reduction. The dechlorination reaction is believed to take place on the surface site of the catalyst via a pseudo-first-order reaction. The final reduction product of o-DCB is benzene. The dechlorination rate increases with the increase of bulk loading of palladium due to the increase of both the surface loading of palladium and the total surface area. Dechlorination efficiency accounts for 90% at Pd/Fe mass ratio 0.02% and metal to solution ratio about 53.3g-L-1 in 120 minutes. Dechlorination is affected by the reaction temperature, pH, Pd/Fe ratio and the addition of Pd/Fe. Ea is found to be 102.5kJ.mol-1 in the temperature ra,nge of 287-313K.     

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.     

裂化催化剂对FCC汽油降烯烃作用的初步研究

Using fixed bed micro-reactor and cracking catalyst, re-cracking of fluid catalytic cracking (FCC) gasoline at lower temperature than conventional cracking condition has been studied. The results reveal that at lower temperature from 350℃-450℃ and catalyst to feed ratio of 3, the olefin content is reduced from 49% to 27%(by mass) over the catalyst whose micro-reacting activation index is 53, and the octane number is kept on high level.     

生物油中乙酸和乙醇共裂化获取汽油产物的研究简

Abstract Acetic acid was selected as the model compound representing the carboxylic acids present in bio-oil. This work focuses the co-cracking of acetic acid with ethanol for bio-gasoline production. The influences of reaction temperature and pressure on the conversion of reactants as well as the selectivity and Conaposition of the crudegasoline phase were investigated. It was found that increasing reaction temperature benefited the conversion of reactants and pressurized cracking produced a higher crude gasoline yield. At 400 ℃ and 1 MPa, the conversion of the reactants reached over 99% and the selectivity of the gasoline phase reached 42.79% （by mass）. The gasoline phase shows outstanding quality, with a hydrocarbon content of 100%.     

Light olefin production by catalytic co-cracking of Fischer–Tropsch distillate with methanol and the reaction kinetics investigation

Catalytic co-cracking of Fischer–Tropsch(FT) light distillate and methanol combines highly endothermic olefin cracking reaction with exothermic methanol conversion over ZSM-5 catalyst to produce light olefins through a nearly thermoneutral process. The kinetic behavior of co-cracking reactions was investigated by different feed conditions: methanol feed only, olefin feed only and co-feed of methanol with olefins or F–T distillate. The results showed that methanol converted to C_2–C_6 olefins in first-order parallel reaction at low space time, methylation and oligomerization–cracking prevailed for the co-feed of methanol and C_2–C_5 olefins, while for C_6–C_8 olefins,monomolecular cracking was the dominant reaction whether fed alone or co-fed with methanol. For FT distillate and methanol co-feed, alkanes were almost un-reactive, C_3–C_5 olefins were obtained as main products, accounting for 71 wt% for all products. A comprehensive co-cracking reaction scheme was proposed and the model parameters were estimated by the nonlinear least square method. It was verified by experimental data that the kinetic model was reliable to predict major product distribution for co-cracking of FT distillate with methanol and could be used for further reactor development and process design.     

Production of biodiesel from waste vegetable oil using impregnated diatomite as heterogeneous catalyst

In this study, biodiesel was produced from waste vegetable oil using a heterogeneous base catalyst synthesized by impregnating potassium hydroxide (KOH) onto diatomite. Response surface methodology based on a central composite design was used to optimize four transesterification variables:temperature (30–120 °C), reaction time (2–6 h), methanol to oil mass ratio (10%–50%) and catalyst to oil mass ratio (2.1%–7.9%). A quadratic poly-nomial equation was obtained to correlate biodiesel yield to the transesterification variables. The diatomite–KOH catalyst was characterized using X-ray diffraction (XRD), Fourier transform infra-red spectroscopy (FTIR) and a scanning electron microscope (SEM) equipped with an energy dispersive X-ray detector (EDS). A maximum biodiesel yield of 90%(by mass) was obtained. The reaction conditions were as follows:methanol to oil mass ratio 30%, catalyst to oil mass ratio 5%, reaction time 4 h, and reaction temperature 75 °C. The XRD, FTIR and SEM (EDS) results confirm that the addition of KOH modifies the structure of diatomite. During impregnation and calcination of the diatomite catalyst the K2O phase forms in the diatomite structural matrix and the active basicity of this compound facilitates the transesterification process. It is possible to recycle the diatomite–KOH catalyst up to three times. The crucial biodiesel properties from waste vegetable oil are within the American Stan-dard Test Method specifications.     

Production of glycerol carbonate via reactive distillation and extractive distillation:An experimental study☆

A process for the production of glycerol carbonate (GC) is proposed with the transesterification of glycerol (GL) and dimethyl carbonate (DMC) with CaO as catalyst by reactive distil ation and extractive distil ation. The perfor-mance of solvents in separating DMC-methanol azeotrope and the effects of operation parameters on the reactive distillation process are investigated experimental y. The results indicate that both the GL conversion and GC yield increase with the DMC/GL molar ratio, reflux ratio, final temperature of tower bottom, and CaO/GL molar ratio and decrease as the recycle number of CaO increases. The calcium concentration in the residual reaction mixture also decreases remarkably as the DMC/GL molar ratio increases. At DMC/GL molar ratio 4.0, reflux ratio 1.0, final temperature of tower bottom 358 K, and CaO/GL molar ratio 0.05, both the GL conversion and GC yield can reach above 99.0%, and the mass concentration of calcium in the product is less than 0.08%.     

甲苯液相催化氧化过程模拟与优化

Liquid-phase oxidation of toluene with air has become the main technology for producing benzoic acid in a reactor at present. Based on the kinetic model of the toluene oxidation process obtained from laboratory and mass balance of key component, a novel model is established to simulate the industrial toluene oxidation process, in which the effects of benzaldehyde and benzyl alcohol are considered and the kinetic parameters are revised by industrial data. The simulation results show that the error of benzoic acid yield is within 3.5%. Based on the simulation model, to maximize the benzoic acid yield, an optimization model is proposed to optimize the operating parameters, including toluene feed-in mass flux and temperature. The optimization result indicates that on the allowable operating conditions the maximum benzoic acid yield obtained with the reaction temperature at 167.2 C an the mass flux at 104.1 t·h^- 1 is greater than the current one, which can be used to guide industrial reactor s operation.     

流化催化裂化汽油改质和增产低碳烯烃的研究

采用GL型催化剂,在小型固定流化床实验装置上考察了反应温度、剂油比、空速和水油比等操作条件对流化催化裂化(FCC)汽油催化改质汽油的产品分布、低碳烯烃(丁烯、丙烯和乙烯)产率和族组成的影响。实验结果表明,在一定反应条件下,FCC汽油通过催化改质可以降低烯烃含量,提高芳烃含量和辛烷值,在满足新汽油标准的同时提高了低碳烯烃的产率。此外,较高的反应温度、剂油比和水油比以及较低的空速有利于FCC汽油催化改质和增产低碳烯烃。     

Study on reformulation of fluid catalytic cracking gasoline and increasing production of light olefins

The effects of reaction temperature, mass ratio of catalyst to oil, space velocity, and mass ratio of water to oil on the product distribution, the yields of light olefins (light olefins including ethylene, propylene and butylene) and the composition of the fluid catalytic cracking (FCC) gasoline upgraded over the self-made catalyst GL in a confined fluidized bed reactor were investigated. The experimental results showed that FCC gasoline was obviously reformulated under appropriate reaction conditions. The olefins (olefins with C atom number above 4) content of FCC gasoline was markedly reduced, and the aromatics content and octane number were increased. The upgraded gasoline met the new standard of gasoline, and meanwhile, higher yields of light olefins were obtained. Furthermore, higher reaction temperature, higher mass ratio of catalyst to oil, higher mass ratio of water to oil, and lower space velocity were found to be beneficial to FCC gasoline reformulation and light olefins production.     

MIP工艺及其专用催化剂的工业应用

抚顺石化分公司石油二厂1．5Mt／a催化裂化装置于2010年12月进行MIP—CGP工艺改造,并于2011年12月使用专用催化剂CGP—FS。应用结果表明,当CGP—FS催化剂占系统藏量75％时,与使用降烯烃催化剂LDO-70时相比,汽油辛烷值RON上升3．5个单位,达到90左右;汽油烯烃保持在32％左有;液化气丙烯含量上升13％;柴油变重、密度增加、十六烷值下降到22．5;油浆变重、密度增加,芳香烃含量达到85％左右;液化气收率增加5．33％,汽油产率下降2．62％,油浆产率下降2．27％,轻收下降2．89％,总液收上升1．44％。     

环烷基瓦斯油催化裂解反应规律及产品性质

利用提升管催化裂解实验装置研究了加拿大合成原油瓦斯油HGO和LGO的催化裂解反应规律和裂解产品性质。发现总低碳烯烃（乙烯、丙烯和丁烯）产率随反应温度和剂油比的增大存在最大值,随反应时间的延长而减小,随水油比的增大而升高。实验确定了HGO催化裂解的优化反应条件：反应温度620～640℃、剂油比16、反应时间2 s、水油比0.5左右。在此反应条件下,乙烯、丙烯和总低碳烯烃产率分别可达9.0%（质量）,15.8%（质量）和32.6%（质量）。催化裂解汽油馏分、柴油馏分和重油馏分含有大量的芳香烃,其中催化裂解汽油馏分总芳香烃含量在80%（质量）以上,主要是甲苯和C₈芳香烃;催化裂解柴油馏分总芳香烃含量在60%（质量）以上,主要是单环和双环芳香烃;催化裂解重油馏分总芳香烃含量在70%（质量）以上,主要是多环芳香烃。     

沸石孔结构对植物油催化裂化性能的影响

制备出硅铝比相近但介孔体积逐渐增加的超稳Y（USY）沸石,进而制备成微球状催化剂。本文在固定流化床装置上,考察了两种植物油的催化裂化性能。小桐子油的评价结果表明,催化剂中USY沸石的介孔体积越大,汽柴油收率越高;汽油族组成中烯烃收率越高,芳烃收率越低,汽油辛烷值和抗爆指数也越低;采用铵交换和水热改性制备介孔体积为0.142cm³/g的USY沸石催化剂的裂化产物中,汽柴油总收率为62.21%（质量分数）,焦炭收率最低,汽油研究法辛烷值达到90.5;大豆油的催化裂化反应规律与小桐子油的一致,中等介孔催化剂裂化得到的汽油研究法辛烷值达到92.2。研究结果表明,采用催化裂化工艺,利用适当介孔的USY沸石催化剂,可以将植物油高效转化为车用轻质燃料,并且得到高辛烷值的汽油。     

高酸原油直接催化裂化反应规律研究

在实验室XTL-5型提升管中试装置上考察了反应温度、剂油质量比和停留时间对苏丹高酸原油催化裂化反应的影响。实验结果表明,在反应温度460℃、停留时间1.15 s、剂油比为6左右的缓和条件下,苏丹高酸原油的重油转化率在90%以上,液收可以达到80%以上。由于原料的残炭质量分数大于8%,导致苏丹达尔原油的直接催化裂化焦炭产率较高。随反应温度的升高和停留时间的延长,转化率不断提高,但汽柴油收率不断下降。随剂油比的增大,汽油产率先升高后降低,柴油收率则不断下降。     

轻烃催化裂解制低碳烯烃反应规律与原料特征化

利用小型固定床实验装置对比研究了轻烃模型化合物的催化裂解性能,从优到劣的顺序依次是正构烯烃、正构烷烃、环烷烃、异构烷烃、芳香烃。正构烷烃、异构烷烃与环烷烃催化裂解的总低碳烯烃收率有较大差别,但是总低碳烯烃选择性却均在56.57%左右。研究了直馏石脑油的催化裂解性能,发现乙丙烯收率和总低碳烯烃收率随反应温度的升高及重时空速的降低而逐渐增大;在反应温度680℃、重时空速4.32 h^-1和水油稀释比0.35的条件下,乙丙烯收率35.87%（质量）,总低碳烯烃收率为41.94%（质量）。针对轻烃催化裂解提出了原料特征化参数KF,它是原料H/C原子比、相对密度与分子量的函数,能较好地表征轻烃原料的催化裂解性能。     

Study on reformulation of fluid catalytic cracking gasoline and increasing production of light olefins

The effects of reaction temperature, mass ratio of catalyst to oil, space velocity, and mass ratio of water to oil on the product distribution, the yields of light olefins (light olefins including ethylene, propylene and butylene) and the composition of the fluid catalytic cracking (FCC) gasoline upgraded over the self-made catalyst GL in a confined fluidized bed reactor were investigated. The experimental results showed that FCC gasoline was obviously reformulated under appropriate reaction conditions. The olefins (olefins with C atom number above 4) content of FCC gasoline was markedly reduced, and the aromatics content and octane number were increased. The upgraded gasoline met the new standard of gasoline, and meanwhile, higher yields of light olefins were obtained. Furthermore, higher reaction temperature, higher mass ratio of catalyst to oil, higher mass ratio of water to oil, and lower space velocity were found to be beneficial to FCC gasoline reformulation and light olefins production. __________ Translated from Chemical Reaction Engineering and Technology, 2006, 22(6): 532–538 [译自: 化学反应工程与工艺]     

委内瑞拉常压渣油萃取窄馏分催化裂化反应性能及产物中硫氮组成

以正戊烷为溶剂,采用超临界溶剂萃取分馏装置将委内瑞拉常压渣油分离为15个窄馏分和一个脱油残渣。采用LHO-1催化剂,在温度500 ℃、剂油质量比4和空速30 h^-1条件下,在小型固定流化床上对不同窄馏分进行催化裂化反应。结果表明,随着窄馏分的变重,干气产率从1.84%升至4.98%,液化气产率从12.18%升至14.47%,汽油产率则从37.49%降至16.73%,柴油产率由23.12%降至17.33%,焦炭产率由9.34%升至20.08%。窄馏分1^＃~4^＃具有良好的裂化性能,窄馏分5^＃~9^＃裂化性能中等,窄馏分10^＃~15^＃裂化性能较差。催化裂化汽油中硫化物主要以噻吩硫为主,尤其是短侧链烷基噻吩,约占90%。催化裂化柴油中硫化物主要为苯并噻吩,约为70%,其次是二苯并噻吩。催化裂化柴油中的含氮化合物主要为苯胺类、 喹啉类、吲哚类和咔唑类,其中,吲哚及其衍生物约占总氮含量的50%,而一甲基、二甲基和三甲基的氮化物含量占氮化物总量的70%以上。