With an increase in energy consumption globally, Fischer-Tropsch (FT) synthesis is a good alternative for producing fuels and chemicals from coal, natural gas or biomass. Among them, coal to liquids has been put into production in countries that have large coal reserves. In this process, Fe-based catalysts are commonly used due to their earth abundance, comparatively wide operation range and ready availability to handle low H-2/CO ratio from coal. Despite their extensive applications, the kinetic and mechanistic understandings of Fe carburization and FT reaction on Fe-carbides are relatively limited due to the complexity of the phase composition of the applied catalysts. This review summarizes the current state of knowledge of FT synthesis on Fe-carbide with an emphasis on the underlying mechanism. Specifically, the employment of a model catalyst, such as Raney Fe, could provide a convenient way to furnish kinetic information regarding Fe carburization and subsequent FT reaction. A major challenge for further understanding catalytic reactions occurring at the Fe-carbide surface is correlating FT activity and selectivity to a specific active site. To address this issue, the advancements of both DFT calculations and surface science techniques are highly demanded.

为了探索熔铁催化剂还原过程中物相变化及对高温费托反应性能的影响,采用SEM(扫描电子显微镜)、EDS(X射线能谱仪)、BET和原位XRD(X射线衍射)对催化剂进行了表征.并在类似工业条件(340℃、2.4MPa、H2/CO比例为3.8)下,于固定床反应器上评价了费托反应性能.分析了不同升温过程、氢气分压、还原空速和还原时间对高温费托熔铁催化剂物相结构、晶粒尺寸、还原度等的影响.结果表明:起始升温速率影响显著,>2.4℃/min时容易使催化剂局部温度过高进而还原速率过快,导致α-Fe晶粒快速长大并团聚.氢气分压影响还原度有转折点,>70％时还原度变化趋势相同;对α-Fe晶粒尺寸的影响表现在低氢分压时更稳定,40h内40％H2/Ar条件仅增加1nm.高还原空速(10000h-1)使得还原催化剂表面孔道分布、孔径尺寸更均匀,还原效率及极限还原度更高;而低还原空速(1000～2000h-1)则使得还原催化剂表/体相结构稳定,晶粒尺寸更稳定,费托合成反应活性高.还原时间在其他条件固定下有最佳值,420℃恒温还原到极限还原度后,α-Fe晶粒尺寸随还原时间延长继续缓慢增长.通过研究获得了适宜的还原条件为:还原升温速率0.4℃/min(200～350℃)～0.8℃/min(<200℃),空速5000h-1,还原时间<30h.

鉴于我国富煤贫油的能源特点,为保障能源安全需求,我国大力发展煤间接液化制油技术,先后建成了7套共计770万t/a的铁基催化剂费托合成煤间接液化示范装置.针对浆态床费托合成反应器中铁催化剂易磨损和失活问题,国家能源集团通过研究铁晶粒大小和硅羟基数对催化剂抗磨强度以及助剂硼对催化剂抗积碳性能的影响,最终确定具有高抗磨强度和性能稳定的CNFT-1催化剂配方,并成功放大应用到400万t煤间接液化装置的2套50万吨级的费托合成反应器中,结果表明,该催化剂具备较高的C3+选择性与抗磨性,技术达到国际先进水平.

采用熔铁催化剂HT-1,在固定床反应器中进行高温费托合成反应,利用GC方法考察了合成气中的CO2对反应的影响.实验结果表明,在系统压力或入口合成气分压不变的条件下,随CO2用量的增加,CO转化率明显降低,H2转化率变化较小,CO2选择性降低;CH4和C2～C4选择性下降,C5+选择性提高;低碳烯烃选择性下降,低碳烃烯烷摩尔比增大.CO2的加入未影响用于费托合成的合成气消耗速率,只是降低了用于水煤气变换反应的CO消耗速率.

从合成气制取低碳烯烃是C1化学化工领域中一个非常有挑战性的研究方向,有间接法和直接法两条路线.以MTO为代表的间接法在工业界已得到了很成功的应用,而直接法流程短、能耗低,与间接法相比更具竞争力,但其工业应用进展缓慢.在相应催化剂研发中,直接法可细分为两条路线:一是耦合双功能催化剂,存在起活温度高、转化率低以及对氢碳比要求高等缺点;二是通过高温费托铁催化剂将合成气一步制取低碳烯烃(FTO).在高温费托合成铁催化体系中,碱金属和金属氧化物是最重要的两类助剂,在载体方面,除了常用的AlO和SiO2,炭材料和分子筛也得到了越来越多的应用.综述聚焦近年来合成气高温费托合成制低碳烯烃铁基催化剂的研究进展,从助剂和载体两个方面进行相应评述,并对FTO铁基催化剂的发展方向进行了展望.

费托合成产物中含多种高附加值含氧组分.部分较低碳数含氧化合物溶解于合成水中,使其具有酸性强、腐蚀性强、刺激性气味、直接生物处理难度大等特点.根据实际组成有针对性地进行资源化利用才能实现经济和环境效益最大化.随着煤间接液化产业发展,费托合成产物中含氧组分资源化利用技术逐渐被更多研究者关注.本文分析了不同费托工艺产生的费托合成水相组成特点,综述了以油分离、酸分离、醇类等分离为步骤的高附加值含氧组分提取分离技术的最新进展,介绍了以高级氧化法、厌氧法等为代表的适用于费托合成废水提质的最新技术研究情况.最后总结了国内外成功工业化的费托合成水相产物处理技术应用情况及实施效果,提出了费托合成产物中含氧组分资源化利用技术的未来发展方向.

To understand the reaction mechanism of coal liquefaction process and further improve the direct coal liquefaction (DCL) technology, a certain kind of DCL oil, which was prepared from a Chinese bituminous Yulin coal, was first separated into different fractions using improved silica-gel column chromatography (SGCC) coupled with the UV-absorbance detector, and then identified by gas chromatography-mass spectrometer (GC-MS), the comprehensive two-dimensional gas chromatography coupled with time-of-flight mass spectrometer (GC × GC-TOFMS), 1H NMR and FTIR. Around 95% of DCL oil was successfully separated into seven fractions by four mobile phases and analysed. It was found that DCL oil consists of 9.06% of alkanes, 36.32% of hydroaromatics, 17.85% of aromatics, 15.39% of oxygen-containing compounds, 16.21% of nitrogen-containing compounds and 2.33% of polyheteroatomic compounds, respectively. [Received: August 22, 2017; Accepted: March 1, 2018]

利用催化剂百吨级中试评价装置,对自主开发的费托合成CNFT-1浆态床铁基催化剂进行了工业运行条件下的2 000 h长周期连续运转试验.催化剂百吨级中试评价装置内浆态床反应器总高28 m,直径DN200,配备有催化剂活化系统、费托合成反应系统、蒸汽包取热系统、催化剂在线置换系统、蜡过滤系统、产物分离系统、气体循环和尾气计量系统等.2 000 h长周期连续运转试验期间C NFT-1催化剂活化温度为250 ～270 ℃,活化压力为2.5～3.0 MPa,恒温时间24 h;费托合成反应温度260 ～270℃,反应压力3.0 MPa,催化剂装填量15 kg.2 000 h长周期性能评价结果表明C NFT-1催化剂在置换率为质量分数13％、置换周期为5～7d的条件下,百吨级中试评价装置稳定运行,催化剂各项性能数据平稳.其中CO总转化率为95％ ～96％,CO2选择性＜20％,CH4选择性为2.2％ ～2.4％;C3收率保持在170 ～ 180 g/m3(标准状态),C3+时空产率为0.94 ～1.05 kg/(kg·h).当量置换周期为5d时,每千克催化剂产C3+数值保持在700 kg左右,置换周期增加为7d时,每千克催化剂产C3+量数值接近1 000 kg.催化剂耐磨性好,重质蜡中铁含量低于25 μg/g.长周期稳定运转试验产品中轻质油品主要组分集中于C6～C9,重质油主要组分集中于C13～C20,重质蜡主要组分集中于C25～C42,合成水中含氧化合物主要组分为正构醇.2 000 h长周期连续运转试验结果表明在煤基浆态床费托合成工业装置工艺条件下,CNFT-1催化剂各项性能指标满足工业生产要求值,完全具备工业应用条件.

为获取铁基催化剂在费托合成反应中的CO转化集总动力学模型,为费托反应器设计和工艺优化提供依据,使用自主研发的工业催化剂CNFT-1(主要成分Fe-Cu-K-B-Si,堆密度0.8g/cm3),基于经典且广泛接受的碳化物机理(Carbide),以次甲基生成基元反应为速率控制步骤,推导了LHHW型CO转化集总动力学模型.在1L搅拌釜反应器(高径比2.5)中首先排除了内外扩散的影响(搅拌转速＞400r/min,空速＞7 000 mL/(g·h)且粒径＜150 μm),然后通过正交试验进行了30组反应动力学实验,条件如下:503 ～553 K,1.0 ～4.0 MPa,8 000 ～20 000 mL/(g·h)以及合成气氢碳比1.0 ～5.0.在此范围内得到的CO转化率20％～70％,基本符合动力学的要求,并且CO转化率和CO2选择性随反应条件的变化趋势符合费托反应基本规律,数据可靠合理.以CO转化率相对残差MARR为目标函数建立模型,通过目标函数最小化(MARR=8.7％,复相关指数R2=0.92)来求解方程并获得最优模型参数,得到动力学模型参数估计值,并根据模型参数所代表的物理意义(合理的活化能Ek=105.0 kJ/mol)和统计意义(Fc=73.3,＞10倍F0.05=3.1,F检验显著),对动力学模型进行了考察.结果 表明:H2吸附热焓小于CO吸附热焓,说明CO在催化剂表面为强吸附,H2相对为弱吸附,这一结果与诸多文献相符.此外,动力学模型活化能Ek的数值也与文献报道值接近,因此,本研究所得的动力学模型可信度较高,可以较好地解释铁基费托催化剂的反应性能.通过本动力学模型得到的CO消耗计算值和实验值相对误差＜15％,可用于费托反应器设计和工艺优化.同时,集总动力学模型不能提供反应产物信息,为解决这一不足,需要进行更复杂的详细产物选择性动力学研究.

Co/Al2O3催化剂在费托合成反应中具有良好的反应性能.采用浸渍法制备了Co/Al2O3催化剂,使用搅拌釜反应器在220 ℃ ,2.0 MPa,10 000 h-1,H2/CO=2.0(体积比)合成气条件下对催化剂的费托合成反应性能进行了评价,评价结果表明随着反应的进行,催化剂的活性逐渐降低,CH4选择性逐渐升高.为研究Co/Al2O3催化剂在费托合成反应中的失活机理,采用N2物理吸附(BET)、X射线衍射(XRD)、透射电子显微镜(TEM)及程序升温加氢(TPH)对不同时间反应后的催化剂进行了表征.表征结果表明在费托合成反应过程中随着反应时间的延长,Co/Al2O3催化剂的孔结构没有发生显著变化,催化剂中部分CoO相被进一步还原为活性相金属Co.此外,在反应过程中活性相金属Co的晶粒尺寸逐渐发生烧结长大,催化剂表面的积碳量快速的增加.因此,活性相金属Co的烧结与催化剂表面的碳沉积应当是本研究中Co/Al2O3催化剂在费托合成反应过程中发生失活的主要原因.为改进催化剂抗烧结能力,对Al2O3载体的孔结构进行调控,进而控制催化剂中活性相金属Co的晶粒分布,减少易于发生烧结的小晶粒金属Co的生成.此外,通过进一步改进催化剂的配方,成功开发了具有高耐烧结性与抗积碳能力的Co基费托合成催化剂.在搅拌釜反应器中对改进后的催化剂进行了1 800 h的费托合成性能测试,在整个反应过程中催化剂表现出高稳定性与低甲烷选择性.

The intrinsic kinetic behaviour of catalytic hydrogenation of acetic acid in vapour phase was studied over a multi-metallic catalyst. The rate expression was derived from the sequence of elementary reaction steps based on a Langmuir-Hinshelwood-model involving two types of active sites. Experiments were carried out in a fixed bed reactor, which is similar to an isothermal integral reactor designed to excluding the negative effects of internal and external diffusion. The reaction conditions investigated were as follow:reaction temperature 275-325 ºC, reaction pressure1.5-3.0 MPa, liquid hourly space velocity (sv) 0.3-1.2 h-1, molar ratio of hydrogen to acetic acid (H/AC) 8:20. The results show that conversion of acetic acid increases with increasing the reaction temperature and pressure, but decreases with increasing the space velocity and H/AC. Furthermore, reducing the reaction pressure and increasing reaction temperature, space velocity and H/AC can improve the reaction selectivity of acetic acid to ethanol. The established kinetic model results agreed with experimental results. The relative difference between the calculated value and the experimental value is less than 6 %. The values of model parameters are consistent with the three thermodynamic constraints. The study provided evidence that the intrinsic kinetic model is suitable both mathematically and thermodynamically, and it could be useful in guiding reactor design and optimization of operating conditions.

The effects of the mass content of water, ethyl acetate and acetaldehyde on the performance of acetic acid hydrogenation to ethanol were studied in a fixed bed microreactor.Experiments were carried out at 285℃, 2.5MPa, 0.8mL/ (mL·h) of acetic acid hourly space velocity (SV), 16 of mole ratio of hydrogen to acetic acid (H/AC).The results show that the acetic acid conversion decreases 4.99％ with the increase of water content from 0to 10.0％, while the selectivity of ethanol shows little change.The acetic acid conversion decreases 3.93％ with the increase of ethyl acetate content from 0to 10.0％, while the ethanol selectivity increases 9.10％.When the ethyl acetate content is 4.4％, the amount of ethyl acetate remains unchanged after reaction.The acetic acid conversion decreases 2.02％ with the increase of acetaldehyde content from 0to 2.0％, while the ethanol selectivity increases 1.31％ and then shows little change.When the acetaldehyde content is 0.4％, the amount of acetaldehyde remains unchanged after reaction.Generally, the acetic acid conversion decreases with increasing the content of water, ethyl acetate and acetaldehyde.Furthermore, the selectivity of ethanol increases with increasing the content of ethyl acetate and acetaldehyde, and remains stable with the increase of water content.

对醋酸直接加氢制乙醇反应的热力学进行了研究.首先根据主副反应的反应物和产物的热力学参数,计算了主副反应的标准摩尔反应焓和标准平衡常数,并进一步研究了反应温度、反应压力以及氢酸的物质的量比对醋酸平衡转化率、乙醇选择性、乙酸乙酯选择性的影响.结果表明,醋酸直接加氢制乙醇的主反应为放热反应且放热量较大,同时放热量随着反应温度的升高而升高,而生成乙酸乙酯的副反应放热量较小且随反应温度的升高而降低;主反应及生成乙酸乙酯的副反应的标准平衡常数都随反应温度的升高而降低,特别是反应温度低于250T时,下降趋势显著;醋酸平衡转化率和乙醇选择性皆随着反应温度的升高而降低,随着反应压力或氢酸的物质的量比的升高而增加,乙酸乙酯选择性与之相反;分析结果表明该反应较适合的反应条件为200～300T,2～3MPa、氢酸的物质的量比为10～20.

Silica-gel column chromatography was improved utilizing the preparative liquid chromatography technology with four mobile phases (n-pentane,dichloromethane,acetic ether/ethyl cyanide and methyl alcohol)to separate and quantify the group components in the low tem-perature coal tar (LTCT)derived from Huolinhe lignite prolysis at 650℃,and each eluted frac-tion was identified by gas chromatography-mass spectrometer (GC-MS).Results show that the main components in LTCT include aromatics,oxygen-containing and nitrogen-containing com-pounds,which account for 22.47%,31.19% and 17.66% of the total mass of the LTCT, respectively.The mass fraction of polyheteromatics is approximately 10% while both the con-tents of alkanes and alkenes are less than 10%.The results from the LTCT components demon-strate that the improved method shows desirable performance for the separation of group compo-nents in coal-based liquid according to their polarity and molecular structures.

Effects of temperature, pressure, acetic acid( HAC) feeding rate and H2/HAC( GHSV or H2 flow) on the conversion of acetic acid, product selectivities and the productivity of ethanol in selective hydrogenation of acetic acid to ethanol were investigated in a fixed-bed reactor. The good stability of the lab-made catalyst was verified. The results show that the reaction rate of esterification and decarboxylation/ketonization are very fast. Selectivities of ethyl acetate and acetone are affected by the catalyst composition and reaction conditions. The hydrodecarbonylation of acetic acid to methane and the further conversion of ethanol can be avoided when the contact time of the reactants with the catalyst is less than 5 s. Optimum reaction conditions were found at 280℃, 2. 5 MPa, LHSV=0. 72 h-1, H2/HAC(mol ratio)=16, under which the selectivity of ethyl acetate could reach 6%. Life time test more than 900 h shows that the lab-made catalyst has a good potential for industrial application.

还原工艺对于费托合成技术的成败具有极其重要的作用.简要介绍了各工业化费托技术使用的还原反应器,并对还原过程中规律性的结果,包括还原中催化剂晶态结构演化,还原气氛、还原温度对催化剂反应性能的影响进行了详细介绍.

To reduce the emission of greenhouse gases and broade the raw material sources of jet fuel, many countries have accelerated the development of bio-jet fuel. The technology for producing bio-jet fuel by hydrotreating vegetable oils or animal fat has been developed by SINOPEC, which contains different processing routes to produce bio-jet fuel and bio-diesel to meet the market demands, such as the route of producing bio-jet fuel maximally, and the route of producing bio-jet fuel and bio-diesel at one time. Relative to vegetable oil or animal fat, the final yield of bio-jet fuel with freezing point lower than -48 ℃ can reach to 35%-45%, the yield of diesel is 7%-11%, and the yield of naphtha is 23%-29%. The bio-jet fuel product fitting for the standard of ASTM D7566-11 has been produced by SINOPEC in an industrial unit, which was successful in the flight-test.

采用精制大豆油于固定床微反装置上考察硫对植物油加氢过程中催化剂活性和化学反应的影响规律。结果表明,硫流失是催化剂失活的主要原因,催化剂一旦失活,补硫仅能恢复其部分活性;进料中添加适量的硫可稳定催化剂活性。不同含硫化合物对催化剂的活性影响不同,H2S对植物油加氢反应的活性有促进作用,而少量噻吩可作为催化剂的硫源,稳定催化剂的活性,但添加量较大时,则会抑制催化剂的活性。此外,H2S和噻吩均可以促进植物油加氢过程中的脱羧基反应。

The first commercial application of the magnetically stabilized bed (MSB) reactor is discussed. The MSB reactor uses a magnetic catalyst in a uniform magnetic field to combine the many advantages of the fixed bed, slurry bed, moving bed, and fluidized bed reactors. An industrial MSB reactor requires a large and uniform magnetic field, which was obtained by optimizing the coil installation spacing and inserting magnetic grids in the reactor. It was used for the intensification of the hydrogenation processes by operating in the chain mode. By utilizing the excellent hydrogenation activity and magnetism of an amorphous Ni catalyst, a MSB reactor was developed for the hydrorefining of caprolactam. Five industrial units of 200-400 kt/a production capacity have been built since 2003. The use of the appropriate magnetic catalyst in the MSB reactor also enhanced activities in CO methanation, selective acetylene hydrogenation and olefin oligomerization. This technology gives new opportunities for process intensification. (C) 2013, Dalian Institute of Chemical Physics, Chinese Academy of Sciences. Published by Elsevier B.V. All rights reserved.

To reduce the emission of greenhouse gases and broaden the raw material sources of jet fuel,many countries have focused on accelerating the development of bio-jet fuel.There are four routes to produce bio-jet fuel from vegetable oil,animal fat and biomass.The first method is two-stage hydrogenation route which includes the step of hydrotreating vegetable oil or animal fat and the followed step of hydroisomerization and selective cracking.The second type of technology uses biomass as feedstock and produces bio-jet fuel by gasification and synthesis.The third method is biomass pyrolysis-hydro-upgrading technology.In this process,the pyrolysis oil is derived from the fast pyrilysis of biomass,and which is treated by dual stage deoxygenation to generate a partially deoxygenated product.The deoxygenated product comprises cyclic hydrocarbon compounds that when fractionated are useful as bio-jet fuel.The other route is bio-butanol conversion method using biomass as feedstock,which includes the steps of fermentation,dehydration,oligomerization and hydrogenation.Being aromatic-free and sulfur-free,the bio-jet fuel is a green fuel for use as blending components with normal jet fuel.