Decalin as the special component of JP-900 is synthesized by naphthalene hydrogenation, in which the improvement of selectivity for cis-decalin is the fundamental for enhancing the combustion performance and density of JP900. The reaction mechanism on six NiM alloys and the reaction rate on NiM alloys with superior activity are investigated based on the density functional theory and microkinetic modeling. The priority of cis product on NiCo(100), NiCu(100) and NiZn(100) surfaces is the result of C atom of related elementary steps receiving the fewer electron from the surface than other alloy surfaces, and the linear-type relationship between D-electron number and priority of cis product is obtained. The alloy surface with preferable activity and selectivity of cis-configuration is NiCo(100) surface. The 473 similar to 713 K favors selectivity of cis-configuration basing on microkinetic modeling. Therefore, this work provides guidance for obtaining Ni-based alloy with preferable activity and selectivity of cis-decalin.

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The adamantane derivatives are promising high-energy-density fuel due to preferable fuel properties, the activity of HY zeolite is key for synthesis adamantane derivatives on account of easy separation from liquid fuels. The effect of acid strength and type of zeolite on activity from DMTCD to 2c,2t-dimethyladamantane is investigated by the DFT method. The activity on HAlY zeolite with stronger Brønsted acid strength is superior compared to HGaY, HFeY, HInY and HBY. Thus, AlO+/HAlY zeolite is investigated obtaining that smaller gap between LUMO and HOMO leads to the better activity than HAlY. And oxoaluminum cations as Lewis acid improves Brønsted acid strength, in which the activity of AlO+/HAlY with stronger Brønsted/weaker Lewis acid strength is preferable than other HAlY with Lewis acid. Therefore, this work provides guidance for screening of HY zeolite with preferable activity of hydro-isomerization.

Nitrogen-containing compounds such as quinoline in coal-based crude oils cause environmental pollution in the course of application. Consequently, dealing with the nitrogen-containing compounds from coal-based crude oil is of paramount importance. The hydrogenation and CN bond cleavage mechanisms of quinoline on the active Mo-terminated over Mo2C(0 0 1) surface, as well as on surfaces doped with W, Pt and Pd monolayers, were examined employing the density functional theory (DFT) method. The Pd and Pt-doped catalysts exhibited higher hydrogenation activity. The catalytic efficiency is enhanced by the loading of different metals, particularly with d-band center further away from the Fermi energy level. Additionally, a novel CN bond cleavage mechanism for quinoline has been proposed. The new proposed mechanism is more conducive for the CN bond cleavage. After a thorough comparison, the Pd-loaded catalyst was identified as the most effective for quinoline hydrogenation and CN bond cleavage.

The nitrogenous aromatic compounds such as quinoline in coal-based crude oil not only generate photochemical smog, but also inhibit the activity of catalyst to a certain extent. The hydrodenitrogenation (HDN) mechanism of quinoline including hydrogenation and ring opening was investigated by using the density functional theory (DFT) on the MoP(010) surface. The favorable pathway is that quinoline generates 1,2,3,4-tetrahydroquinoline (THQ1) through hydrogenation, and then undergoes C-N bond cleavage through the Hoffman elimination mechanism (E2). In addition, the effect of S in coal-based crude oil on quinoline HDN was also investigated. The introduction of S leads to the transfer of more electrons from the uppermost surface of MoP(010) to the S, which improves the HDN activity for the MoP(010) surface by reducing the hydrogenation energy barrier for the quinoline to THQ1. The microkinetic analysis indicates that the actual temperature (650 K) is more favorable for the HDN of quinoline on the MoP(010) surface.

To solve the problem of efficient extraction of coal liquefied oil residue, the extractants with different properties, such as aliphatic hydrocarbon, aromatic hydrocarbon, oxygen-containing compounds, and simulated coking benzene, were selected for the extraction of coal liquefied oil residue. And the effects of solubility and polarity parameters of extractants on extraction rate and extract components were investigated. The results show that with the increase in solubility and polarity parameters of extractants, the extraction rate for coal liquefied oil residue increased and then decreased. The influence of the solubility parameter of extractants on the extraction performance was mainly reflected in their matching degree with the solubility parameter of the extractable components. The effect of the polarity parameter of the extractants was mainly the breaking of the associated structure of coal liquefied oil residue. When the solubility parameters of the extracts and extractants were close, the extraction performance was good, such as aromatic hydrocarbon and tetrahydrofuran. The main components of these extracts were polycyclic aromatic hydrocarbons. The extractants with larger polar parameters were more likely to destroy the associated structure of coal liquefied oil residue, resulting in higher contents of N and S elements in acetone, ethanol, and methanol extracts. Simulated coking benzene was a good solvent for extracting coal liquefied oil residue, which was easy to be recovered from solution, and the extraction rate of coal liquefied oil residue could reach more than 50%.

Decalin is the major ingredients of High-energy-density jet fuel JP-900, in which cis-decalin possesses more excellent combustion performance than trans-decalin. The various coordination environments on metal catalysts are crucial to evaluate activity of catalyst and selectivity of cis-decalin, the density functional theory and microkinetic modeling are applied to investigate the effect of various active sites on the process of naphthalene hydrogenation. Active sites with generalized coordination numbers of 7.50, 6.67, 5.57, and 5.50 from four Ni surfaces including Ni(1 1 1), Ni(1 0 0), Ni(1 1 0) and Ni(2 1 1) are built, respectively. To screen surfaces with preferable selectivity to cis-configuration, the four reaction paths are firstly considered including desorption of NA8H, direct hydrogenation of NA8H to cis- or trans-NA9H, and NA8H to trans-NA9H by hydrogen transfer on four surfaces. And the Ni(1 0 0) and Ni(1 1 1) surfaces exhibit optimal selectivity to cis-decalin by comparing energy barrier of the four paths and calculating the energy barrier gap between direct hydrogenation to cis- and H transfer to trans- configuration, which is the result of 9th C atom receiving more electrons in the process of generating trans-decalin. In addition, reaction mechanism of the whole reaction process from naphthalene hy-drogenation to decalin was explored and finding that the rate-determining step of reaction lies in the process of the second-ring hydrogenation. Furthermore, the activity of the Ni(1 0 0) surface is not worse than that of Ni(1 1 1) by comparing the energy barrier of the rate-determining step, which is consistent with the analysis of the d -band-center for different surfaces and the adsorption energy for naphthalene. Microkinetic analysis shows that the temperature between 473 K and 553 K favors the selectivity to cis-decalin for metal Ni catalyst. Therefore, this study provides guide for screening surfaces with different coordination numbers with high activity of naphthalene hydrogenation and high selectivity to cis-decalin.

The structures of high-energy-density fuel are significant factors to influence property, which in turn determines the flight distance and payload of vehicles. The density functional theory and molecular dynamics simulation are employed to predict properties of adamantane derivatives, and explore the effect of structure with the different substitutes and the isomers on properties including density, net heat value, specific impulse, thermal and oxidation stability. For adamantane derivatives with different substitutes, the C/H ratio is treated as the de-scriptors of density and net heating value. While the number of secondary carbon atom attached by side chains and the gap between HOMO and LUMO are viewed as the descriptors of density and volumetric net heating value for isomers, respectively. Based on the above descriptor, the structures with superior properties are obtained for ethyladamantane, propyladamantane and butyladamantane. The structure of pentyladamantane with excellent properties (2c-ethyl-2t,4c,4t-trimethyladamantane) is predicted due to resembling structure of adamantane de-rivatives with preferable properties. The thermal and oxidation stability of 2c,2t-dimethyladamantane, 2c-ethyl-2t-methyladamantane, 2c,2t-diethyladamantane and 2c-ethyl-2t,4c,4t-trimethyladamantane with superior properties is close to tetrahydro-dicyclopentadiene meeting requirement of aircraft. Therefore, the guidance, that predicts, screens and assesses the structure and property of adamantane derivatives, is provided in this study by defining descriptors.

Coal liquefaction pitch is a byproduct rich in polycyclic aromatic hydrocarbon generated during coal liquefaction process, and can be used to prepare porous carbon electrodes for electric double-layer capacitors. However, the effects of the proportion of pore volume in different pore size ranges on the electrochemical properties of porous carbon are still not well investigated. Herein, porous carbon was fabricated from liquefaction pitch and KOH at a mass ratio of 1:2 and activation temperatures of 600-900 & DEG;C. The results showed an increase in both specific surface area and total pore volume of the samples with the activation temperature, inconsistent with the changing trend of the specific capacitances due to well-stored electrolyte ions in micropores. In particular, micropores with pore volume diameter below 1 nm greatly impacted the specific capacitance performance of porous carbon. The pore volume with pore width below 1 nm first increased and then decreased with the activation temperature. Among samples, porous carbon prepared at activation temperature of 700 & DEG;C delivered the highest specific capacitance of 329 F g(-1 )at a specific current of 0.5 A g(-1), and retained 254 F g(-1) of specific capacitance at 20 A g(-1) in 6 mol L-1 KOH electrolyte. The reason for this was related to the largest pore volume with pore width below 1 nm (0.43 cm(3) g(-1)). Afterward, the optimized sample was assembled into a symmetrical supercapacitor and test results showed that 96.37% of the initial capacitance was retained after 10,000 cycles at 1 A g(-1), suggesting good cycling stability. In sum, the as-prepared porous carbon is very promising for use as electrode material for supercapacitors.

Capture of elemental mercury (Hg-0) attracts global attention because of its toxicity and bioaccumulation. Carbon-based sorbents are extensively studied due to the high porosity that can increase Hg-0 adsorption ability. In this study, the RS-based sorbents were prepared from sulfur-containing coal liquefaction residue raffinate slag (CLR-RS), an industrial waste, by CH3COOK activation. The N-2 adsorption, XRD, SEM, XRF, Hg-TPD, and XPS techniques were used to study the physicochemical properties of sorbents. The sorbent that was prepared at 850 degrees C from the blend of CH3COOK/RS at 3:5 (by mass) exhibited excellent Hg-0 removal performance under N-2 + O-2, and an improved performance was observed under N-2 + O-2 + SO2 + NO + H2O. The Hg-TPD and XPS analyses revealed that HgS and HgO were formed on used RS-based sorbents. O-2 in flue gas could improve the ability in capturing Hg-0 by promoting the formation of HgS and HgO. The findings have suggested that the prepared sorbents based on CLR-RS could be potentially applied for industrial Hg-0 capture, and the sustainable utilization could be realized by recycling RS.

Extract residue of coal liquefaction residue (ERCLR) is a solid mixture of high carbon, high ash, high sulfur, and complex composition, mainly including unconverted coal, inorganic minerals, and coal liquefaction catalyst. The effective use of ERCLR, which has high utilization value based on high hydrogen-to-carbon ratio, not only improves the thermal efficiency and economy of coal liquefaction process, but also reduces the emissions of pollutants. The energy efficiency analysis, environmental impact, and economic analysis of three power generation systems were calculated and analyzed by Aspen Plus. The three power generation systems are ERCLR gasification combined cycle power generation system, ERCLR combustion power generation system, and ERCLR pyrolysis combustion power generation system. The results show that the energy efficiency of ERCLR gasification combined cycle power generation system is 47.5%, which is better than that of ERCLR combustion power generation system (43%) and ERCLR pyrolysis combustion power generation system (45.3%). The flue gas emission of ERCLR gasification combined cycle power generation system has lower impact on environment than that of the other two systems. ERCLR gasification combined cycle power generation system provides a lower cost of electricity (0.44 CNY/kWh), compared with ERCLR combustion power generation system (0.48 CNY/kWh) and ERCLR pyrolysis combustion power generation system (0.69 CNY/kWh). Therefore, ERCLR gasification combined cycle power generation system has significant advantages over the other two utilization approaches. For the recovery and utilization of ERCLR, ERCLR gasification combined cycle can be given priority to power generation.

将我国丰富的煤炭资源经合成气转化为混合醇,作为合成气化学重要的研究领域,该技术的突破对于提高煤化工产品品味、实现煤炭清洁利用、降低醇类化学品石油依赖度具有重要意义,受到了国内外工业界和学术界的广泛关注.制约合成气制混合醇发展的瓶颈在于高效能催化剂的开发,合成气制混合醇催化剂包括贵金属催化剂、改性甲醇合成催化剂、改性费托合成催化剂和钼基催化剂,对以上催化剂逐一进行介绍,详细阐述了国内外最新研究进展,并对各类催化剂性能做出简要评价,为合成气制混合醇早日实现工业应用提供借鉴.

The typical processes of high-temperature Fisher-Tropsch synthesis are discussed.The development and recent advances are reviewed.The fusion iron,precipitated iron and supported iron catalyst for high-temperature Fisher-Tropsch synthesis and the deactivation mechanism thereof are described.The downstream processing routes for Gasoline,diesels,oxy-organics andα-olefins are discussed.The technical economics of the process is analyzed.

采用376mm×3000mm的大型流化床冷模实验装置,对比了甲醇制烯烃SHMTO工艺反应器中设置格栅内构件前后流动规律的差异。结果表明,反应器内设置格栅内构件后,床层平均颗粒质量浓度降低,压力脉动显著降低,表明格栅可以有效地破碎气泡、改善气-固接触传质和提高床层操作的稳定性。增设格栅后反应器内气-固流动更趋均匀,还可以强烈抑制固体颗粒以及气体的轴向返混。借鉴已有流化床放大效应的研究可以推测,工业SHMTO反应器设置格栅后有利于稳定床层操作、改善气-固接触效果和防止气体返混,有利于改善反应产物的分布和产品选择性。但现有的格栅结构仍需进一步优化,以满足工艺和工程设计的需要。

In order to promote the development of Jet fuels in China,three coal-based Jet fuels that are JP-900,coal-based full synthetic Jet fuel and Jet fuel from direct coal liquefaction were reviewed in this paper. For these three coal-based Jet fuels,the research history and preparation methods were systematically reviewed. Furthermore,by comparing performance testing data of the coal-based Jet fuels and pe-troleum-based Jet fuels,the physicochemical properties and service performance of the coal-based Jet fuels were discussed. Finally,the development strategies of coal-based Jet fuel were proposed. The JP-900 was essentially free of surfur and nitrogen,significantly more dense than typical Jet fuels,and had a high flash point,low freeze point and low polar compound. Furthermore,the thermal stability and combustion property of JP-900 were superior to that of the petroleum-based Jet fuels. Compared with the characteristics of typical JetA-1, the coal-based full synthetic Jet fuel achieved the same or better thermal stability,lubricity and elastomer compatibility. The Jet fuel from direct coal liquefaction had the same hydrocarbon type as that in JP-900 which was high density,high flash point,low freezing point and rich in cyclanes. However,the heteroatomic compound significantly effected its performance. The coal-based jet fuels were not used in bus-iness application except coal-based full synthetic jet fuel. In order to achieve commercial production and business application of the coal-based Jet fuels,the production capacity of coal liquefaction should be improved,the testing methods and product standard for coal-based Jet fuels should be regulated.

The coking on SAPO-34 molecular sieve catalyst for methanol to olefins (MTO) process was studied based on the industrial data of a turbulent fluidized bed reactor in Shenhua Group MTO plant. The carbon difference between spent and regenerated catalysts, residence time of the catalyst in the reactor and mass ratio of methanol to catalyst (MTC) were correlated according to Voorhies model, mechanism model and linear model, and kinetics models for the coking at different temperature were obtained. The results showed that for the same data, all the chosen models have a similar fitting degree and the fitting degree of the carbon difference with MTC was higher than that with residence time. The reliability of the models will significantly be affected by the stability of the installation. The fitting degree of the established models should be heightened because of the complexity of operating the industrial reactor.