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.     

甲醇作为催化裂化部分进料的反应过程

基于甲醇制低碳烯烃（MTO）与催化裂化（FCC）反应及工艺过程的分析、比较,提出二者结合的可能性,将甲醇作为FCC部分进料用以增产低碳烯烃.根据FCC过程特点,通过实验考察反应温度、甲醇水溶液、积炭催化剂等因素对甲醇转化的影响;验证了甲醇在FCC条件下可具有较高的低碳烯烃产率.实验结果表明：在40％(质量分数)甲醇水溶液进料、未积炭催化剂、反应温度550～600℃的条件下,甲醇转化的烃产率可达26.3%～28.1％(质量分数),低碳烯烃占烃组成的67.8%～66.5％(质量分数).同时对甲醇在FCC条件下的反应特点进行了初步分析.研究结果为进一步实现甲醇作为FCC部分进料提供了重要依据.     

分子筛催化剂上催化裂化汽油掺混甲醇的改质研究

以实现甲醇制取低碳烯烃转化工艺和FCC汽油降烯烃工艺的有效组合为目的,在固定床微型反应装置上,使用SAPO-34、ZSM-5、DOCO以及分子筛组合催化剂,对FCC汽油掺混甲醇改质进行了研究。主要对反应温度、空速和混炼比等影响因素进行了考察。结果表明,SAPO-34分子筛上甲醇制取低碳烯烃效果较好,高烯烃含量汽油在SAPO-34分子筛上的氢转移和芳构化效果显著,ZSM-5分子筛上的芳构化反应效果和DOCO的异构化反应效果较显著,甲醇转化与汽油转化反应间的相互协同作用,既有利于甲醇转化成低碳烯烃又能提高汽油降烯烃转化深度。适宜的混炼条件:反应温度400℃,m(甲醇):m(汽油)=0.05,空速3h~(-1),组合催化剂上,产物汽油中烯烃含量较FCC粗汽油下降23%以上。     

催化裂化汽油改质降烯烃反应规律及反应热

利用催化裂化催化剂在小型固定流化床实验装置上对催化裂化汽油催化改质降烯烃过程的反应规律进行了实验研究,详细考察了反应温度、剂油比和重时空速对产物收率和汽油辛烷值的影响,得到了催化裂化汽油改质过程的最佳实验操作条件：反应温度为400～430℃,剂油比为7左右,重时空速为20～30 h-1。在此基础上,计算了汽油改质过程的反应热,分析了反应条件对反应热的影响,揭示了反应热的变化规律。结果表明,低温改质为放热过程,高温改质为吸热过程。改质条件对反应热影响的强弱顺序为反应温度>剂油比>重时空速。     

重油催化裂解制低碳烯烃工艺条件研究

采用固定流化床催化裂化试验装置,以中国石油兰州石化公司3.0 Mt·a-1重油催化裂化装置所用原料油为原料,考察反应温度和剂油质量比对重油催化裂解制低碳烯烃性能的影响,在确定的适宜操作条件下研究中国石油兰州石化公司重催装置原料在不同催化剂上的催化裂解制低碳烯烃的反应性能。结果表明,较适宜的操作条件为:反应温度590℃,剂油质量比为7,与降烯烃催化剂和重油裂解催化剂相比,多产丙烯催化剂的低碳烯烃产率可达25.53%,更适合作为重油催化裂解制低碳烯烃时使用。     

催化裂化汽油临氢异构化/芳构化改质过程的反应特性

采用工业Ni-Mo/Al₂O₃-HZSM-5催化剂在小型固定床加氢微反装置上对催化裂化（FCC）汽油临氢改质过程的反应特性进行了研究,通过考察反应温度、压力、空速和氢油体积比对改质后的FCC汽油烃类组成的影响,分析了汽油中不同烃类的转化性能。结果表明,氢油比对产物组成影响不大,高温、低压、低空速有利于增加芳烃的选择性,低温、高压、高空速则有利于增加异构烷烃的选择性;临氢改质后,FCC汽油的烯烃含量明显降低,芳烃和异构烷烃含量增加,因而产品汽油的辛烷值基本保持不变;全馏分、轻馏分和重馏分FCC汽油临氢改质实验结果表明,烯烃含量较高的轻馏分具有更高的转化活性;在FCC汽油临氢改质过程中,同碳数的端烯烃反应活性高于内烯烃,直链烯烃的反应活性高于支链烯烃。     

Conversion of canola oil to various hydrocarbons over Pt/HZSM-5 bifunctional catalyst

Canola oil conversion was studied at atmospheric pressure over Pt/HZSM-5 catalyst (0.5 mass% Pt) in a fixed bed micro-reactor. The operating conditions were: temperature range of 400?500°C, weight hourly space velocity (WHSV) of 1.8 and 3.6 h^?1 and steam/oil ratio of 4. The objective was to optimize the amount of gasoline range hydrocarbons in the organic liquid product (OLP) and the selectivity towards olefins and isohydrocarbons in the gas product. The gas yields varied between 22–65 mass% and were higher in the presence of steam compared to the operation without steam. The olefin/paraffin mass ratio of C₂-C₄ hydrocarbon gases varied between 0.31–0.79. The isohydrocarbons/n-hydrocarbons ratio was higher with Pt/HZSM-5 (1.6–4.8) compared with pure HZSM-5 catalyst (0.2–1.0). The OLP yields with Pt/HZSM-5 (20–55 mass% of canola oil) were slightly lower compared to HZSM-5 (40–63 mass% of canola oil) under similar conditions. The major components of OLP were aliphatic and aromatic hydrocarbons. A scheme postulating the reaction pathways for the conversion of canola oil over Pt/HZSM-5 catalyst is also presented.     

我国FCC催化剂的发展近况

阐述了国内近几年FCC催化剂在重油催化裂化、汽油降烯烃、脱硫及多产低碳烯烃方面的进展.提高抗重金属污染能力、用中孔沸石代替 ZSM-5小孔沸石及大幅度提高催化剂基质的活性仍是今后研发 FCC催化剂的热点.     

催化汽油改质降烯烃多产丙烯反应规律的研究

在小型固定流化床实验装置上,以燕山石化催化汽油为原料,对催化汽油改质过程进行了实验研究,并对反应过程气体产品和液体产品的组成进行了详细分析,考察了反应温度、重时空速、剂油比以及催化剂的活性对改质过程产物分布的影响,发现在催化汽油改质过程中,各操作条件对改质过程产物分布均有不同程度的影响,通过选择合适的操作条件,在保证低烯烃含量的同时,实现多产丙烯是可行的,在适宜的条件下,汽油烯烃体积分数可降到11.8%,同时,液化气中丙烯质量分数达到了44.4%.     

催化裂化汽油二次反应过程中反应热的变化

根据热力学理论,通过产物和反应物的生成焓计算了催化裂化汽油在降烯烃改质以及催化裂解过程中的反应热,并根据不同反应过程的实验结果考察了反应温度、停留时间和剂油比对反应热的影响。计算结果表明,催化裂化汽油降烯烃改质和催化裂解过程都是吸热反应体系,降烯烃改质过程的反应热为80～150 kJ·kg^-1,催化裂解过程的反应热为370～620 kJ·kg^-1;反应条件对反应热的影响通过改变反应物的转化率和产物分布实现。在实验条件范围内,随着反应温度的升高、剂油比的增大和停留时间的延长,反应热逐渐增大;当剂油比增大到一定程度时,反应热随剂油比的增加趋势变缓。     

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.     

FCC提升管反应器中终止剂注入对裂化反应的影响

通过对催化裂化提升管注入终止剂前后的工况进行数值模拟,研究了终止剂注入对提升管内速度分布、催化剂颗粒浓度分布、温度分布以及组分浓度分布的影响,考察了不同注入量以及注入高度的终止剂在提升管内的作用区域及其对裂化反应的影响。研究表明,终止剂的注入大幅提升了提升管内的油气速度,降低了催化剂浓度、油气和催化剂的温度,使得提升管内原料的裂化程度降低,二次反应减少。且不同注入量和注入高度的作用区域不同,对裂化反应的影响不同,应根据实际工况进行分析。     

Behavior of sulfur species present in atmospheric residue in fluid catalytic cracking

The selective removal of sulfur species in atmospheric residue (AR) is strongly wanted since the species of the hydrodesulfurized AR (HDS-AR) define the sulfur content of the product gasoline in the subsequent fluid catalytic cracking (FCC). Hence, the correlations between sulfur species in HDS-AR and FCC gasoline were explored in the present study. HDS-AR was fractionated into vacuum gas oil (VGO) and vacuum residue (VR) by distillation. Reactivities of HDS-AR (S = 3000 mass ppm) and its VGO (S = 900 mass ppm) were measured by micro activity test to clarify which fractions and sulfur compounds in HDS-AR were converted into gasoline and its sulfur species. The yields and sulfur contents of the product gasoline were 45.0 mass% and 52 mass ppm from HDS-AR and 47.7 mass% and 14 mass ppm from VGO, respectively. The sulfur content of the gasoline from HDS-AR was markedly higher than that from HDS-VGO. The saturate and aromatic fractions in HDS-AR are mainly converted to the gasoline in the FCC process, providing similar gasoline yields from HDS-VGO and HDS-AR. Thiophene, methylthiophenes, and benzothiophenes were major sulfur species in both gasolines from HDS-AR and HDS-VGO. Such sulfur species are concluded to be derived from benzothiophenes in VGO and dibenzothiophenes in VR fractions, respectively through hydrogen transferring ring opening and dealkylation during FCC. Sulfur compounds are also produced from H₂S and olefins in FCC, increasing the sulfur content in the product gasoline. The larger sulfur content in the gasoline from HDS-AR than that from HDS-VGO is ascribed to more H₂S being produced during the FCC process as well as dibenzothiophenes being present in the feed.     

重油催化裂解汽柴油二次裂解性能研究

This paper investigated the secondary cracking of gasoline and diesel from the catalytic pyrolysis of Daqing atmospheric residue on catalyst CEP-1 in a fluidized bed reactor.The results show that the secondary cracking reactivity of gasoline and diesel is poor,and the yield of total light olefins is only about 10%（by mass）.As reaction temperature increases,ethylene yield increases,butylene yield decreases,and propylene yield shows a maximum.The optimal reaction temperature is about 670℃for the production of light olefins.With the enhance- ment of catalyst-to-oil mass ratio and steam-to-oil mass ratio,the yields of light olefins increase to some extent. About 6.30%of the mass of total aromatic rings is converted by secondary cracking,indicating that aromatic hy- drocarbons are not easy to undergo ring-opening reactions under the present experimental conditions.     

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。     

DOC-Ⅰ降烯烃催化剂小型提升管反应性能评价

采用小型提升管催化裂化试验装置评价研制的DOC-Ⅰ降烯烃催化剂的催化裂化反应性能。结果表明,在反应温度500 ℃、剂油质量比6和停留时间1.99 s条件下,DOC-Ⅰ催化剂上原料油的转化率达75.01%,较参比催化剂提高1.79个百分点,相应的液化气产率降低0.28个百分点,汽油产率增加2.9个百分点,烯烃含量下降5.21个百分点,异构烷烃和芳烃含量明显增加,产品分布有效改善。表明研制的DOC-Ⅰ催化剂具有较好的催化裂化性能和降烯烃能力。     

催化裂解反应条件对产物收率的影响

增产低碳烯烃、轻质芳烃等产物是催化裂解技术发展的趋势,反应条件是影响催化裂解产物分布的关键因素。介绍催化裂解过程涉及的反应机理,概述反应温度、剂油质量比、停留时间(空速)、水油质量比等反应条件,裂解装置和原料油性质对产物收率的影响,结合工业实例分析反应条件对产物收率的影响。     

汽油催化裂化二次反应规律的研究

在固定流化床实验装置上考察了汽油在庆阳催化剂上的催化裂化二次反应规律,给出了温度和剂油比对汽油二次反应的影响。结果表明反应温度及剂油比对汽油的族组成有很大的影响;随着反应温度升高,异构烷烃、环烷烃含量降低,芳烃和烯烃含量有明显的增加,正构烷烃的含量变化不明显;剂油比的增大时,异构烷烃、环烷烃的转化率逐渐增大,而烯烃的转化率先增大后趋于稳定。     

扩孔剂对β沸石催化剂FCC轻汽油醚化性能的影响

制备了催化裂化轻汽油β分子筛醚化催化剂。在小型连续流动固定床反应装置进行了催化裂化轻汽油的醚化反应。考察了催化剂成型过程中，不同分子量和不同质量分数的聚乙二醇(PEG) 、浸渍氧化物方式、挤条成型与浸渍先后顺序对Hβ沸石的醚化反应活性影响, 同时还考察了醚化反应温度、压力、醇烯比和空速对醚化反应的影响。实验结果表明，添加质量分数为10%的扩孔剂PEG-4000成型，再共同浸渍氧化物制备的Hβ分子筛催化剂具有最佳的醚化反应活性。在最佳反应条件（温度70 ℃，压力0.8 MPa，空速1.0 h^－1,醇烯摩尔比1.0）下，叔碳烯烃转化率达到62.93%。