Zn-P/HZSM-5催化剂上催化裂化汽油馏分的芳构化

在实验室制备了ω(ZnO)=2％的Zn／HZSM-5和ω(ZnO)=2％、ω(P2O5)=5％的ZnP／HZSM-5催化剂，并以75～120℃催化裂化汽油馏分为原料，在小型固定床反应装置上考察了工艺条件对Zn-P／HZSM-5催化剂芳构化反应性能的影响。结果表明，Zn-P／HZSM-5催化剂在反应温度430℃、反应压力0.1MPa、液时空速1.Oh^-1的反应条件下，原料中烯烃和烷烃转化率分别达到97.17％和67．91％，液相产品中烯烃含量、芳烃含量及异构烷烃含量分别为3．28％，74．09％，20．59％，与Zn／HZSM-5催化剂相比具有更高的活性稳定性和芳烃选择性。     

轻烃在HZSM-5催化剂上芳构化的研究进展

综述了轻烃芳构化催化剂的研究进展,分析比较了各种改性HZSM-5催化剂的特点,讨论了HZSM-5催化剂失活的原因。认为对纳米HZSM-5分子筛进行改性将是轻烃芳构化催化剂今后发展的趋势。     

Zn-Ga/HZSM-5分子筛芳构化催化剂

以硝酸锌或硝酸镓为改性剂,纳米HZSM-5分子筛为原料,采用浸渍法可制备单(双)金属改性HZSM-5分子筛催化剂(负载Zn,Ga质量分数分别为6.0%,0.1%)。以正丁烷或异丁烷为原料,在反应温度为400～550℃,反应压力为0.8 MPa,质量空速为0.60 h^-1的条件下,研究了不同金属离子负载顺序对所制备催化剂芳构化反应性能的影响。结果表明：在反应温度为550℃的条件下,以异丁烷为研究对象,采用Zn-Ga/HZSM-5分子筛催化剂,转化率达到93.75%,芳烃选择性达到46.54%;以正丁烷为研究对象,选用Ga-Zn/HZSM-5分子筛催化剂,上述各值依次为62.18%,49.52%;与单金属改性HZSM-5分子筛催化剂相比,双金属改性不仅可以提高异丁烷和正丁烷芳构化反应性能,还能够降低干气收率,抑制小分子烃的生成。     

反应条件对HZSM-5基催化剂芳构化反应的研究进展

从温度、空速、催化剂、氧气和微波加热等方面,详细地论述了反应条件对HZSM-5基催化剂芳构化反应,认为适当的温度、低空速、改性HZSM-5、无氧和微波加热等条件对芳构化反应是有利的。     

水热处理对Zn-P/HZSM-5催化剂芳构化性能的影响

在不同温度下对HZSM-5分子筛进行水热处理并用浸渍法对其进行Zn和P改性,制备了Zn-P/HZSM-5催化剂;以流化催化裂化汽油50~100℃馏分为原料,考察了水热处理温度及水热处理顺序对Zn-P/HZSM-5催化剂芳构化性能的影响。实验结果表明,随水热处理温度的升高,催化剂的初始活性下降,而稳定性则先提高后降低;550℃水热处理后再经Zn和P改性的Zn-P/HZSM-5催化剂表现出较好的芳构化性能,在反应温度410℃、反应压力0.5M Pa、液态空速1.0h-1、反应时间16h的条件下,烯烃转化率、液相产物中芳烃质量分数及液相产物收率分别为90.26%,54.06%,74.62%;先对HZSM-5分子筛进行水热处理再用Zn和P对其改性的Zn-P/HZSM-5催化剂,比先用Zn和P对其改性而后进行水热处理的Zn-P/HZSM-5催化剂的活性和稳定性好。     

预处理温度对NH4F改性Mo/HZSM-5催化剂上甲烷无氧芳构化反应的影响

在经NH4F改性的Mo/HZSM-5催化剂上进行甲烷无氧芳构化反应,考察预处理温度对催化剂性能的影响.实验结果表明,NH4F改性有效地延长了催化剂的寿命,并提高了反应活性;NH4F改性降低了HZSM-5分子筛上强酸位的浓度,提高了催化剂的抗积碳性能.     

Mo-P/HZSM-5催化剂临氢芳构化性能研究

将硅铝原子比为38的HZSM-5分子筛在不同浓度的氢氧化钠碱溶液中处理后,通过离子交换法脱除部分硅原子,改善孔结构。以HZSM-5分子筛为载体,钼酸铵和磷酸二氢铵做钼源和磷源,用共浸渍法制备了氧化态前体,采用程序升温还原法制备出了负载型磷化钼催化剂,采用XRD和N2-吸附进行表征。在小型连续固定床反应器上以全馏分FCC汽油为原料,考察碱溶液浓度和工艺条件对芳构化反应的影响。结果表明,最佳的碱溶液浓度为0.20 mol/L,在反应温度360℃、压力2.0 MPa、空速2 h-1、氢油比400∶1时,液相产品中芳烃质量分数为32.39%,烯烃质量分数为17.18%,液体收率为93.5%。     

液化石油气在ZnNi/HZSM-5催化剂上的芳构化

用浸渍法制备ZnNi/HZSM -5催化剂 ,通过对液化石油气的芳构化试验表明 ,其活性明显高于HZSM -5催化剂。在常压、温度 540℃、质量空速 1h- 1条件下 ,芳烃和苯 -甲苯 -二甲苯 (BTX)混合物收率分别达到 4 8%和4 5%左右 ,液态产品中芳烃质量分数高达 98%。同时还考察再生活化温度、再生活化时间和反应温度对芳构化催化作用的影响。结果表明 ,再生活化温度对催化剂的恢复影响比较大 ,只有达到 575℃ ,活化时间至少 2h ,催化剂活性才能完全恢复 ;低温段 ( 550℃ )再生活化时 ,再生活化时间将影响催化剂活性 ;反应温度在 50 0～ 550℃时 ,随着反应温度增加 ,液体收率和芳烃收率随之增加 ,对芳烃选择性影响不大 ,BTX收率幅度波动较大。用金属改性的ZnNi/HZSM -5催化剂具有较强的芳构化能力。     

制备工艺对Mo/HZSM-5催化剂甲烷脱氢芳构化性能的影响

采用室温浸渍抽滤工艺、室温浸渍旋蒸工艺和室温球磨浸渍工艺三种方法制备了Mo/HZSM-5催化剂,并在流化床反应装置上对催化剂上的甲烷芳构化反应性能进行了考察。结果表明,与室温浸渍抽滤工艺相比,用室温浸渍旋蒸工艺和室温球磨浸渍工艺所制备的催化剂Mo物种的担载量较高,并具有较高的甲烷转化率(分别为16%~19%和18%~21%)、总芳烃选择性(分别为85%和83%)和较低的磨损指数(分别为0.71%/h和0.85%/h)。     

NiO改性HZSM-5分子筛催化剂催化1-丁烯芳构化反应

以N iO改性的HZSM-5分子筛为催化剂,在固定床微反装置上考察了N iO负载量、焙烧温度、焙烧时间等对1-丁烯芳构化反应性能的影响。用X射线衍射、N2吸附脱附、红外光谱表征催化剂的物化性质,研究了高温焙烧和负载N iO前后催化剂的结构、表面酸性质及其变化规律,并与反应性能相关联,得出1-丁烯在催化剂上的反应历程。研究结果表明,N iO的最佳负载量(质量分数)为2.0%,适宜的预处理条件为在空气中675℃下焙烧4h,此时催化剂的催化活性和芳烃选择性都最高,1-丁烯转化率达到84%,芳烃选择性达到59%。     

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.     

Aromatization of FCC Gasoline Over Modified HZSM-5 Catalyst

Abstract

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.     

氧对丙烷在HZSM－5上转化为轻质芳烃的影响

考查了不同温度下Ｏ＿２对丙烷在不同ＳｉＯ＿２／Ａｌ＿２Ｏ＿３比的ＨＺＳＭ－５上芳构化的影响。结果表明，Ｏ＿２的添加提高了丙烷转化率和芳烃选择性。讨论了不同ＳｉＯ＿２／Ａｌ＿２Ｏ＿３比与完全氧化活性之间的关系；结合临Ｈ＿２对丙烷转化的影响，推测氧除与气相氢作用外，还与催化剂表面氢物种作用，促进了烷烃活化，加速了对应烯烃的生成。提出了Ｏ＿２促进Ｃ＿４－Ｃ＿６等中间体转化；Ｏ＿２参与反应后抑制了氢转移反应。讨论了反应历程。     

氧对丙烷在Ga／HZSM－5上催化芳构化影响的研究

利用连续和脉冲反应技术，考察了添加少量氧对丙烷在Ｇａ／ＨＺＳＭ－５上催化芳构化的影响。试验结果表明，氧的存在对丙烷转化为芳烃ＢＴＸ不利。通过进一步条件试验，对氧的作用进行了分析讨论，认为这与催化剂中活性组份镓的存在直接相关。     

轻质烃在双功能ZnNi/HZSM-5催化剂上的芳构化

考察了混合碳四烃、石油液化气和正己烷在双功能ZnNi/HZSM -5催化剂上的芳构化 ,同时首次将微波辐射技术应用到芳构化中 ,并分别研究了混合碳四烃和正己烷在两种加热方式下的芳构化催化行为     

催化裂化汽油馏分在P—Zn／HZSM-5催化剂上的芳构化

以50～100℃的FCC汽油馏分为原料,在连续固定床反应器上考察了工艺条件对P-Zn／HZSM-5催化剂在芳构化反应中性能的影响。结果表明,在反应温度410℃、反应压力0．5MPa、液时空速1．0h^-1的操作条件下,液相产物中的烯烃、异构烷烃和芳烃的含量分别为8．56％,13．07％,73．39％。催化剂P-Zn／HZSM-5具有较好的芳构化降烯烃效果。     

Influence of Aromatization Reaction Conditions in the Presence of HZSM-5 Catalyst

The reaction conditions include temperature, weight hourly space velocity (WHSV), catalyst loading amount Ga and Si/Al, vapor, calcination temperature, soaking order, pretreatment, oxygen, and microwave heating method. The study introduces the influence of aromatization reaction conditions over HZSM-5 catalyst in detail. The proper temperature, low weight hourly space velocity (WHSV), modified HZSM-5, non-oxygen and microwave heating method are beneficial to the aromatization reaction.     

Influence of Aromatization Reaction Conditions in the Presence of HZSM-5 Catalyst

Abstract

The reaction conditions include temperature, weight hourly space velocity (WHSV), catalyst loading amount Ga and Si/Al, vapor, calcination temperature, soaking order, pretreatment, oxygen, and microwave heating method. The study introduces the influence of aromatization reaction conditions over HZSM-5 catalyst in detail. The proper temperature, low weight hourly space velocity (WHSV), modified HZSM-5, non-oxygen and microwave heating method are beneficial to the aromatization reaction.     

粘结剂对HZSM-5芳构化催化剂的性能影响研究

The effect of different binders on light hydrocarbon aromatization performance of the HZSM-5 catalyst was investigated.Physicochemical properties of the catalysts,such as the specific surface area,pore volume and acidity,etc.,were characterized to correlate with their aromatization performance data.The results showed that the pore structure of Al2O3 could significantly affect the catalyst performance.As the accessible pore diameter of the catalyst increased from 8.0 nm to 9.0 nm,the light aromatics yield increased by 2.7 percentage points,while the operating time of the catalyst nearly doubled.In addition,catalysts prepared with SiO2 and aluminum phosphate was more active and stable than that prepared with Al2O3,of which the light aromatics yield enhanced 6-8 percentage points and the run length,or seivice eife run length nearly doubled.