Production of synthesis gas from methane using compression ignition reformer

A new form for a partial oxidation compression ignition reformer, which is different from existing methods of reformation, is suggested to which the concept of super-adiabatic combustion is applied. In addition, experiments are conducted on variables such as the oxygen/methane ratio, the total flow rate, the intake preheating temperature, and the oxygen enrichment ratio, all of which affect the production of hydrogen, in order to understand the optimal features of the movement of the reformer. Results showed that the concentration of hydrogen and carbon monoxide was 20.84% and 13.36%, respectively, under the optimal standard conditions of an oxygen/methane ratio of 0.26, a total flow rate of 106.5 L/min, and an intake preheating temperature of 355 oC. Under the same conditions, the concentration of hydrogen decreased to 20.31% when the oxygen enrichment ratio was 55.6%, while that of carbon monoxide increased to 20.85% when the oxygen enrichment ratio was 50.33%.     

Reactions of synthesis gas

The use of synthesis gas (syngas) offers the opportunity to furnish a broad range of environmentally clean fuels and chemicals. There has been steady growth in the traditional uses of syngas. Almost all hydrogen gas is manufactured from syngas and there has been a tremendous spurt in the demand for this basic chemical; indeed, the chief use of syngas is in the manufacture of hydrogen for a growing number of purposes. Methanol not only remains the second largest consumer of syngas but has shown remarkable growth as part of the methyl ethers used as octane enhancers in automotive fuels. The Fischer-Tropsch synthesis remains the third largest consumer of syngas, mostly for transportation fuels but also as a growing feedstock source for the manufacture of chemicals, including polymers. Future growth in Fischer-Tropsch synthesis may take place outside the continental United States. The hydroformylation of olefins (the oxo reaction), a completely chemical use of syngas, is the fourth largest use of carbon monoxide and hydrogen mixtures; research and industrial application in this field continue to grow steadily. A direct application of syngas as fuel (and eventually also for chemicals) that promises to increase is its use for Integrated Gasification Combined Cycle (IGCC) units for the generation of electricity (and also chemicals) from coal, petroleum coke or heavy residuals. In the period 2005–2015, the amount of syngas employed in this manner may approach that used for all other specific purposes. Syngas is the principal source of carbon monoxide, which is used in an expanding list of so-called carbonylation reactions.     

天然气转化制备合成气工艺进展

综述了天然气转化制备合成气的国内外工艺技术进展，提出了一些看法和观点。     

New synthesis gas chemistry

Recent research at Texaco regarding new synthesis gas chemistry has focused on (a) the production of aliphatic primary amines through olefin oxoamination using CO/H₂ plus ammonia, (b) the amidocarbonylation of olefin and aldehyde substrates for the synthesis of a variety of amidocarboxylic acids and (c) the development of a Texaco Fischer-Tropsch process for the generation of low MW alcohol fuels. Both the scope and chemistry of these syntheses will be discussed in this chapter. Important classes of chemical products that can be made using this technology include surface active agents, specialty surfactants, food additives, chelating agents, as well as intermediates for sweetness, anticorrosion agents and paint dispersants.     

Isobutanol from synthesis gas

A highly active and selective Zr-Zn-Mn-Li-Pd catalyst for the one-step synthesis of 2-methyl-1-propanol (isobutanol) from synthesis gas is described. This catalyst produces 60 wt% isobutanol at a rate of 740 g isobutanol per liter catalyst and hour. The catalyst was optimized by a statistical method indicating that during catalyst preparation pH and temperature control are essential.Abbreviations GHSV gas hourly, space velocity defined as volume incoming syngas/volume catalyst and hour at standard conditions - MTBE methyl tert. butyl ether     

Evaluation of natural gas based synthesis gas production technologies

A comparative study of nine synthesis gas technologies have been carried out. The basis was syngas feed to a 2500 MTPD methanol plant. Material and energy balances were calculated, investments and operational costs were estimated, and a comparison was made. The comparison indicates that autothermal reforming and combined reforming with prereformer are preferable among the proven technologies. Among emerging technologies GHR, KRES and CPO have an economic advantage. However, the margins are probably too small to be significant.     

Production of synthesis gas by autothermal reforming of iso-octane and toluene over metal modified Ni-based catalyst

The reforming process of gasoline is an attractive technique for fuel processor or hydrogen station applications. We investigated catalytic autothermal reforming (ATR) of iso-octane and toluene over transition metal supported catalysts. The catalysts were prepared by an incipient wetness impregnation method and characterized by N₂ physisorption, XRD, and TEM techniques before and after the reaction. Many of the tested catalysts displayed reasonably good activity towards the reforming reactions of iso-octane. Especially, Ni/Fe/MgO/Al₂O₃ catalyst showed more activity than the other catalysts tested in this study including commercial HT catalyst. Ni/Fe/MgO/Al₂O₃ catalyst showed good stability for 700 h in the ATR of iso-octane. No major change was observed in catalytic activity in ATR of iso-octane or in the structure of catalyst. Since iso-octane, toluene are surrogates of gasoline, Ni/Fe/MgO/Al₂O₃ catalyst can be considered as ATR catalyst for gasoline fuel processor and hydrogen station systems.     

Detonation properties of the synthesis gas

Investigated parameters of combustion and detonation of mixtures of the synthesis gas with oxygen and air are presented. The ratios between carbon oxide and hydrogen and between the fuels and oxidizer are varied within wide ranges. The critical energy of detonation initiation is determined. __________ Translated from Fizika Goreniya i Vzryva, Vol. 43, No. 6, pp. 90–96, November–December, 2007.     

焦炉煤气掺烧驰放气的生产实践

对焦炉煤气掺烧驰放气的工艺进行了介绍,并考察分析了掺烧驰放气的影响,结果表明,掺烧驰放气后,焦炉的高向加热得到改善,燃烧室温度波动减小,劳动强度降低,地下室主管压力提高,直行温度符合规定的标准温度,对烟道吸力、石墨的生成、推焦基本没有影响,经济效益显著。     

Direct synthesis of isoparaffin from synthesis gas under supercritical conditions

To produce isoparaffins from synthesis gas directly, modified Fischer–Tropsch (FT) synthesis was carried out under supercritical conditions using n-butane as a medium. One-step FT synthesis using a hybrid catalyst consisting of Co/SiO₂, HZSM-5 and Pd/SiO₂ was carried out. Introduction of supercritical-phase n-butane increased light isoparaffins significantly and suppressed the formation of the by-product, methane. Under supercritical-phase butane, hydrogenolysis and isomerization reactions were promoted. Due to the fact that the optimum temperatures for FT and HZSM-5 catalysts are different, 513 K and over 573 K, respectively, two-step FT synthesis was also carried out to optimize the reaction temperatures. The first-step reaction used Co/SiO₂ catalyst containing small amount of HZSM-5 for FT synthesis at 513 K, and the second-step reaction used a hybrid catalyst containing Pd/SiO₂ and zeolite for hydrogenolysis and isomerization of hydrocarbons at 573 K. Introduction of supercritical n-butane increased the isoparaffin selectivity, and decreased the methane selectivity significantly. The production of heavy hydrocarbons C₉+ was inhibited in both gas and supercritical phase. The isoparaffin selectivity in the gas phase decreased with time-on-stream, but very stable for the supercritical-phase reaction. Because water and heavy hydrocarbons were removed from active sites on zeolite and the zeolite acidity was promoted in the supercritical medium, the selectivity of isoparaffin was considered stable. Among zeolites added to the hybrid catalyst in the second-step reactor, HZSM-5 and H-beta zeolite were suitable for producing light isoparaffins. These results indicated that two-step FT synthesis under supercritical n-butane was superior for producing light isoparaffins from synthesis gas directly.     

焦炉煤气制合成气反应器数值模拟

采用CFD软件F luent模拟计算焦炉煤气(COG)非催化局部氧化制合成气反应器,其中湍流模型选择标准k-ε模型,热辐射选择P-1模型,用非预混模型计算化学输运和反应。反应器内组分与温度场的数值模拟结果与实验测定结果基本吻合,说明模拟结果是可信的。通过模拟可预测,当氧气与焦炉煤气进气体积比达到0.14左右时,可以获得最好的焦炉煤气的转化效果。本数值模拟可为COG非催化局部氧化制合成气进一步的工程研究与应用提供可靠的理论参考依据。     

Direct synthesis of middle iso-paraffins from synthesis gas on hybrid catalysts

This paper focuses on the synthesis of iso-paraffin-rich hydrocarbons by Fischer–Tropsch synthesis (FTS) over silica gel supported Co catalyst (Co/SiO₂). The basic concept is to isomerize and/or hydrocrack the primary FTS hydrocarbon products. A physical mixture consisting of a small amount of zeolite or Pd/zeolite mixed with Co/SiO₂ enhanced the formation of C₄–C₁₀ iso-paraffins while suppressing the formation of higher molecular hydrocarbons, probably because of the selective cracking of these hydrocarbons on them. In separate experiments, a two-reactor system was used. The first reactor contained a physical mixture of Co/SiO₂ and zeolite, and the second reactor contained zeolites or Pd-supported zeolites. The two-reactor system gave sharp C-number distribution within C₃–C₆ and iso-paraffins-rich products. The hydrocracking of n-octane and n-decane (model compound simulating products of the FTS reaction) over mixed catalysts composed of various compositions of Pd/SiO₂ and ZSM-5 in the presence of gaseous hydrogen showed high and stable activity, and produced primarily iso-paraffin-rich hydrocarbons. The isomerization was favored for mixtures rich in Pd/SiO₂. The role of Pd was thought to be the inlet of hydrogen spillover to the zeolite surface.     

焦炉煤气综合利用制取液化天然气

本文介绍了一种焦炉煤气利用新技术,将焦炉煤气中的甲烷和氢气从煤气中分离出来。分离出的甲烷生产液化天然气（LNG）,氢气通过锅炉燃烧产生蒸汽,可以提供动力和热力。此工艺具有投资规模小、焦炉煤气利用率高、收益大、无污染等特点,是中小焦化企业焦炉煤气综合利用、提高经济效益的好途径。     

Partial oxidation of methane to synthesis gas

Partial oxidation of methane to synthesis gas has been carried out over a number of transition metal catalysts under a range of conditions. It is found that the metals Ni, Ru, Rh, Pd, Ir and Pt, either supported on alumina or present in mixed metal oxide precursors, will bring the system to equilibrium. The yield of CO and H2 improves with increasing temperature in the range 650–1050 K, and decreases with increasing pressure between 1 and 20 atm. An excellent yield (92%) is obtained with a 421 N₂CH₄O₂ ratio at 1050 K and atmospheric pressure, with a space velocity of 4×10⁴ hour^–1.     

Production of benzene,toluene, and xylenes from natural gas via methanol: Process synthesis and global optimization

A systematic global optimization‐based process synthesis framework is presented to determine the most profitable processes to produce aromatics from natural gas. Several novel, commercial, and/or competing technologies are modeled within the framework, including methanol‐to‐aromatics, toluene alkylation with methanol, selective toluene disproportionation, and toluene disproportionation and transalkylation with heavy aromatics, among others. We propose a stand‐alone chemicals facility: the main products are aromatics with allowable by‐products of gasoline, liquefied petroleum gas, and electricity. Several case studies are discussed that produce varying ratios of para‐, ortho‐, and meta‐xylene across multiple refinery capacities. The results indicate that utilizing natural gas for the production of aromatics is profitable with net present values as high as $3800 MM dollars and payback periods as low as 6 years. The required investment for these refineries represents as much as a 65% decrease compared to published estimates of similar coal‐based capacity plants. © 2016 American Institute of Chemical Engineers AIChE J, 62: 1531–1556, 2016     

合成气中氯含量的测定

德士古煤气化工艺气流中的氯,常在强还原气氛中被转化为氯化氢。氯化氢的测定是该工艺的重要检测项目之一。下面介绍合成气中氯含量的测定方法。1　测量原理氯化氢可用氢氧化钠溶液吸收,采用硫氰酸汞光度法测定其中氯含量。合成气中还有硫化氢存在,可用醋酸锌吸收消除干扰。氯化氢与硫氰酸汞反应置换出的硫氰酸根,与铁离子作用生成硫氰酸铁红色化合物,根据其吸光度,采用分光光度法定量。2　仪器气泡吸收管;具塞比色管;分光光度计;湿式流量计。3　试剂吸收液:c(NaOH)=0.05mol/L;无水乙醇;硫氰酸汞-乙醇溶液:称取0.4g硫氰酸汞溶于100ml无水…     

Thermodynamic equilibrium in the synthesis of dimethyl ether from synthesis gas

Chemical equilibrium in dimethyl ether synthesis from synthesis gas was studied thermodynamically over wide ranges of gas compositions and process parameters.     

NHD溶剂脱除合成气中COS气体的讨论

近年来,NHD脱硫、脱碳技术已得到广泛应用,不仅应用于合成氨原料气的脱硫及变换气的脱碳,还逐渐向其他领域扩展.如甲醇生产过程中原料气的脱硫、脱碳,羰基合成所需CO气体中酸性气的脱除等.在上述原料气体中,均含有一定量的COS气体.由于制气原料、制气方法及预处理工艺不同,其COS含量也不相同.合成反应要求将合成气中总硫脱除到0.1×10-6以下,以保护催化剂,一般通过干法精脱硫工艺来实现,也可以在NHD脱碳的同时,脱除COS.     

天然气水合物生产工艺研究现状

介绍了天然气运输的方式、天然气水合物的基本特性、生产原理、技术路线和几种生产工艺,分析了常见天然气储运方式的物理特性及其经济性,对天然气水合物储运技术的应用前景进行了展望.