FCC汽油在ZSM-5分子筛上的芳构化反应

考察了全馏分催化裂化（FCC）汽油的芳构化改质反应，结果表明，在三种不同硅铝比的分子筛中，以硅铝比为50的分子筛为载体所制备的催化剂性能较好。对Ni、Mo、Zn、Co4种金属活性组分的选择考察，以Zn为活性组分的催化剂芳构化性能最好，以Ni为活性组分的催化剂液收最高。分析了FCC汽油中不同烃类的芳构化反应历程．得出金属组分应有适宜的含量。     

Cd-ZSM-5沸石催化剂的制备、表征和芳构化催化性能

采用离子交换、浸渍和混合三种方法制备镉改性ZSM-5沸石催化剂,考察了改性方法和镉含量对催化剂的表面酸性和Cd状态以及芳构化性能的影响。结果表明,加入镉降低了B酸性,Cd~(2+)与沸石结合形成了L_(1612)酸中心,其生成量取决于改性方法和Cd含量,并与芳构化活性提高有直接关系。     

A Study on the Selectivity of Methanol Aromatization

Abstract

The present study describes the performance of the HZSM-5 zeolite catalyst modified by Cu, Zn, Ga, La, P, Ag, and other ions for the conversion of methanol to aromatics in a fixed-bed reactor, and the influences of the system pressure and temperature on methanol aromatization are in discussion. The results show that the optimum single ion for the modification of catalyst was Zn or Cu. The optimum combined ions were Zn and Ga. The yield of aromatics could reach up to 66.6% on the catalyst modified with Ga2% and Zn10%.     

在FX-02沸石催化剂上苯与乙烯烷基化反应的研究

采用固定床鼓泡反应器,在ＦＸ ０２沸石催化剂上进行苯与乙烯烷基化反应的研究。通过加速失活试验,考察了不同工艺条件对催化剂操作寿命的影响,得到了使苯转化率和乙苯选择性较高及反应产物中二甲苯含量极低的适宜的工艺条件。     

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。     

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。     

ZSM－5沸石上合成甲胺的研究

在常压固定床反应器上研究以ＨＺＳＭ－５和ＺＳＭ－５为催化剂的甲胺合成反应。结果表明，ＺＳＭ－５催化剂有明显的择形催化作用，能有效的抑制三甲胺的生成，并有较高的活性。经Ｐ改性后的ＰＺＳＭ－５对三甲胺有更强的抑制作用。催化剂的吸附等温线给果表明，Ｐ的掺入使ＺＳＭ－５的孔道变窄，增加了吸附氨和一甲胺的酸性位，减少了吸附二甲胺和三甲胺的酸性位，从而有效的抑制了三甲胺的生成。     

The Aromatization of Different FCC Naphtha Fractions over a P-Zn/HZSM-5 Catalyst

Abstract

The aromatization reaction performance of P-Zn/HZSM-5 catalyst was investigated on a fixed bed reactor using five fluid catalytic cracked (FCC) gasoline fractions (<100°C, 50°C–100°C, <120°C, 75°C–120°C, and full fraction) as feedstock, and the effect of feedstock on aromatization is discussed. The results showed that the activity and stability of P-Zn/HZSM-5 catalyst for the aromatization of the 50°C–100°C fraction were high in definite reaction conditions. After 16 hr, the content of olefin and aromatics in liquid product were 5.23 and 79.9%, respectively. The liquid product of low olefin and high aromatics was obtained. The distribution of benzene, toluene, and xylene in liquid product of 50°C–100°C fraction was investigated during aromatization, and the result showed that the toluene content was maximum among the three aromatics contents, the benzene content was minimum at the beginning of the reaction, xylene content became maximum, and benzene was still minimum after reacting for 20 hr. The content of C₉ ⁺ aromatics increased at the first stage of the reaction and then decreased with the increasing reaction time.     

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。     

载体及反应条件对Pt/BaKL沸石催化剂芳构化性能的影响

研究了γ-Al_2O_3或SiO_2载体,以及反应条件对Pt/BaKL沸石催化剂芳构化性能的影响。发现经过碱化或负载Sn的γ-Al_2O_3作为载体,能够较好地保持该催化剂在正己烷芳构化反应中的高活性和高选择性,并有益于改善Pt/BaKL沸石催化剂的抗硫性能。     

在ZSM－5分子筛上引入Zn、Ga物种对乙烷芳构化的影响

报道了在Ｚｎ、Ｇａ改性的ＺＳＭ－５分子筛上进行乙烷芳构化与乙烯芳构化反应的结果，并考察了反应温度对Ｚｎ－ＺＳＭ－５催化剂乙烷芳构化性能的影响和催化剂Ｇａ－ＺＳＭ－５的焙烧时间对其性能的影响等。试验结果表明：（１）乙烷脱氢活化步骤是乙烷芳构化反应的控制步骤，Ｚｎ、Ｇａ物种对乙烷脱氢活化起着至关重要的作用，并且ｚｎ物种的作用大于Ｇａ物种。Ｚｎ、Ｇａ物种还能促进聚合环化物脱氢向芳烃转化：（２）升高反应温度对乙烷脱氢活化和聚合环化物脱氢有利，同时会使聚合环化物的裂解反应速度增加，因而在乙烷芳构化反应中存在最佳温度；（３）延长焙烧时间，有利于乙烷的活化及乙烯、Ｃ＿３等芳构化中间产物向芳烃的转化。     

ZSM-5/MCM-48复合分子筛基催化剂上甲醇制汽油反应工艺条件的研究

<正>甲醇转化为烃类液体燃料和化学品是当前替代石油技术研究的热点之一。早期由Mobil公司首先以提其出独了特甲的醇孔制道汽结油构(在MMTTG)G反技应术。中Z表S现M-出5良分好子筛的催化性能[1],但其强酸性导致油相产物中的芳烃含     

Study on Aromatization of C6 Aliphatic Hydrocarbons on ZRP Zeolite Catalyst

The performance of ZRP zeolite catalysts for aromatization of C6 aliphatic hydrocarbons was investigated in a pulsed microreactor. The influence of metal modified ZRP zeolites on aromatization reaction was also studied, coupled with comparison of aromatization tendencies of olefins, paraffins and paraffins with different degrees of chain branching. Test results had shown that the lower the silicon/aluminum ratio in the ZRP zeolite, the higher the aromatization reactivity of aliphatic hydrocarbons. Modification of ZRP zeolite by zinc and its zinc content had apparent impact on the yield and distribution of aromatics. The aromatization tendency of olefins was apparently better than paraffins, while the aromatization tendency of monomethyl paraffins was better than that of straight-chain paraffins with the exception of dimethyl paraffins, which had worse aromatization tendency because of their steric hindrance.     

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。     

Progress in the Field of Converting Methanol into Light Olefins over the ZSM-5 Zeolite Catalyst

Technical progress in the field of conversion of methanol into ethylene and propylene over the ZSM-5 catalyst was summarized. The economical analysis of the technology, the mechanism of chemical reaction and reaction kinetics were introduced. The factors including the effect of the operating conditions,the influence of catalyst preparation conditions and modification of ZSM-5 zeolite on the reaction and coke formation were also discussed.     

纳米ZSM-5-MCM-41的制备及其在汽油芳构/加氢脱硫中的应用

以纳米ZSM-5为硅源,采用分子筛硅源法制备了纳米ZSM-5-MCM-41介微孔复合分子筛,并对合成试样进行了XRD、NH3-TPD、SEM及Py-IR等表征,考察了晶化过程中体系pH值、晶化温度、晶化时间、模板剂用量和碱溶液浓度对ZSM-5-MCM-41复合分子筛结构及性质的影响。采用模拟原料油,在高压微反装置上评价了以复合分子筛为载体制备的Co-Mo/ZSM-5-MCM-41催化剂的催化性能。结果表明,与基于机械混合载体的催化剂相比,基于分子硅源法制备复合分子筛载体的催化剂有较高的芳构性能和脱硫性能,在压力1.5MPa、温度350℃、氢油体积比300,空速2h-1条件下,模拟原料的芳构产率和脱硫率分别为15.08%和95.48%。     

ZSM-5沸石膜的水热稳定性研究

考察了ZSM-5沸石膜在400℃水蒸气处理200 h条件下的水热稳定性,用气体渗透实验、XRD、SEM对水蒸气处理前后的膜管进行了表征,比较了两者的差别。实验结果表明,在水蒸气处理后,ZSM-5沸石膜出现一定的脱铝现象。对气体的渗透率由原来的1.45×10-7mol／(Pa·s·m2)降为2.9×10-8mol／(Pa·s·m2),然后趋于稳定。根据表征结果。对ZSM-5沸石膜的脱铝现象进行了讨论,分析了ZSM-5沸石膜脱铝的机理以及在高温条件下水蒸气处理对ZSM-5沸石膜的影响规律,为工业放大研究沸石膜乙苯催化脱氢制苯乙烯过程提供参考。     

甲苯歧化反应中ZSM-5沸石催化剂积碳规律的研究

采用积分反应器研究了甲苯非临氢歧化反应中ZSM-5沸石催化剂的积碳规律,得到了积碳速率与反应时间的关联式,并考察了不同反应参数对积碳的影响。结果表明,随着歧化反应的进行,积碳量逐渐增加,而积碳速率逐渐下降;提高反应温度及使用低硅铝比的沸石催化剂,均导致积碳及失活速率加快;在实验范围内,空速及催化剂颗粒度对积碳过程无显著影响。此外,反应初期催化剂上的少量积碳有利于甲苯歧化反应,但积碳量达到一定程度后,甲苯转化率及二甲苯收率均显著下降。     

Zn/ZSM-5分子筛晶粒大小和预处理条件对丙烷芳构化性能的影响

在常压连续流动固定床反应器上,以Ｚｎ／ＨＺＳＭ － ５ 为催化剂,考察了分子筛晶粒大小、焙烧温度、水热处理温度和正硅酸乙酯改性对丙烷芳构化转化率、芳烃收率以及产物分布的影响。用吡啶吸附红外光谱表征了分子筛的表面酸性和酸强度（Ｂ 酸和Ｌ 酸） ,并与反应结果进行关联,得出了一系列有意义的结果。