利用焦炉气生产合成氨

山东济南化肥厂,已部分利用“济钢”的焦炉气,采用常压催化部分氧化法制取合成氨原料气。目前每小时可以处理2800～3300米~3焦炉气,将来可以每小时处理8000米~3。焦炉气一般含氢50～60％,甲烷25～30％。常压催化部分氧化法,是将焦炉气,水蒸汽、空气混合后,再通过内有     

天然气常压无催化剂部分氧化法造气试验

该厂在油头改为气头的改扩建工程中，进行了天然气常压无催化剂部分氧化法造气试验，试验结果表明此法工艺简单、技术可靠、投资少、见效快，具有经济效益、环境效益。     

热水解氧化法在含油污泥脱水及脱重金属方面的应用

利用热水解氧化法及络合剂协同氧化法对含油污泥进行了无害化处理。大幅降低了污泥的含水率及重金属含量。探讨了热水解氧化法,常温常压络合剂法以及络合剂协同热水解氧化法对含油污泥中的重金属去除效果,考察了处理后污泥符合作为燃料相关指标,为污泥的再利用,提出一个新的思路。     

二氧化氯催化氧化处理农药废水的研究

对在常温常压下二氧化氯催化氧化法处理农药废水进行了实验研究和工程上的实际应用，并和没有放置催化剂时单纯的二氧化氯氧化进行对比。结果表明常温常压，在表面催化剂存在的条件下,二氧化氯催化氧化在处理高浓度农药废水中，化学需氧量（chemical oxygen demand，COD）的去除率达到75％,色度的去除率达到95％。     

甲烷常压非催化部分氧化制合成气研究

考察了常压下甲烷非催化部分氧化制合成气过程中,甲烷转化率、气体产物产率以及积炭率随反应器温度、进气配比、原料气流量变化的影响。通过考察反应器温度对制备合成气过程的影响结果,分析了甲烷非催化部分氧化制合成气过程的反应机理。     

重要文章导读

碳酸二甲酯的生产技术与市场分析 原文节录:目前,碳酸二甲酯(DMC)的工业生产方法有光气法、酯交换法和甲醇氧化羰基化法。甲醇氧化羰基化法又分为液相法、气相法、常压非均相法。光气法是DMC最早的合成方法,其原料有毒,工艺流程长,污染严重,应逐步淘汰。酯交     

钢铁酸洗废液的回收利用研究

采用直接通空气法与直接通氯气法，将Fe^2 氧化为Fe^3 探讨了最佳转化条件，认定以pH值5．5、温度80℃、常压下通空气22h直接氧化为可行，并试制出产品铁红粉，回收率为77%。     

山东省利用焦炉煤气生产合成氨经验

山东省化工战线的广大工人阶级、革命领导干部和科技人员,在毛主席革命路线指引下,在山东省委的正确领导下,已采用天然气、焦炉气为原料生产合成氨。济南化肥厂已部分利用“济钢”的焦炉气,采用常压催化部分氧化法(用空气)制取合成氨原料气,目前每小时可以处理2800—3200米~3焦炉气,将来可以处理8000米~3/时焦炉气,生产     

PEP聚醚型非离子表面活性剂的合成与性能研究

本文以聚乙二醇和环氧丙烷为原料，用常压法合成了一系列“氧化丙烯－氧化乙烯－氯丙烯”嵌段共聚醚，对 进行了结构表征，对反应影响因素了探讨，并对产物的表面活性性能进行了测定研究。     

常压法防老剂4020对NR胶料热氧老化的防护

研究了常压法防老剂 40 2 0对NR胶料的硫化特性、自由状态和应力状态下的热氧老化防护性能及氧化起始温度的影响。试验结果表明 ,常压法防老剂 40 2 0对NR胶料硫化特性的影响与防老剂A、D、40 10NA和高压法40 2 0相近 ;对NR胶料的热氧老化防护性能和氧化起始温度高于防老剂A、D和高压法 40 2 0 ,与防老剂 40 10NA相近 ;在NR胶料中常压法防老剂 40 2 0的用量以 0 5～ 1 5份为宜。     

霍林河褐煤常压固定床气化的生产分析

结合煤质化验数据和管式试验炉试烧试验,对霍林河褐煤在常压固定床气化工业化生产过程中,气化炉内氧化层温度、氧化层层次波动、煤气成分、焦油产率、炉出煤气温度和压力等生产数据和现象进行了系统的分析和总结,揭示了褐煤常压固定床气化的特殊性。     

Effect of the pressure on the catalytic oxidation of volatile organic compounds over Ag/Al2O3 catalyst

The catalytic oxidation of volatile organic compounds (VOCs: ethanol, 1-propanol and 2-propanol) over Ag/Al₂O₃ catalyst under low and normal atmospheric pressure conditions has been studied with synchrotron vacuum ultraviolet (VUV) photoionization mass spectrometry (PIMS). The partial oxidation intermediates of the VOCs under different pressures were identified by PIMS and their photoionization efficiency (PIE) spectra. Alkene is preferentially formed under the low pressure conditions, while aldehyde and acid are favored under the normal atmospheric pressure conditions. In addition, the low pressure conditions are more suitable for observing the active intermediates, such as ethenol, ketene and propenal. The results indicate that the pressure has a significant effect on the oxidation pathway of VOCs over Ag/Al₂O₃ catalyst.     

The mixing sensitivity of polysulphide generation

The effect of mixing and mass transfer on polysulphide generation by catalytic oxidation of sodium sulphide was studied using two batch‐operated reactors. One was a sparged reactor operated at atmospheric pressure and low mixing intensities (0.37 to 28 W/kg), the other was an unsparged pressurized reactor characterized by high mixing intensities (17 to 3100 W/kg). The reaction parameters examined included the impeller speed, sparged gas flowrate, oxygen partial pressure, and catalyst loading and type. In both reactors the maximum polysulphide yield, selectivity and rate of formation increased with increasing energy dissipation. Increased gas sparging increased the rate of reaction, but had little effect on either yield or selectivity. Increased oxygen partial pressure increased the rate of oxidation but decreased both the yield and selectivity. The type of catalyst dramatically affected the yield of polysulphide produced for a given set of reaction conditions with improved mixing increasing reaction rate, yield and selectivity.     

Further Studies on Oscillations over Nickel Wires During the Partial Oxidation of Methane

Oscillatory reactions over nickel wires during the partial oxidation of methane were investigated in a tubular continuous flow reactor made of quartz at atmospheric pressure. A modified thermocouple was designed to measure the temperature while the interposed nickel coil worked as a catalyst. Significant effects on the oscillations were observed by varying the system temperature and the feed gas composition, and by cutting off one of the reactant gases temporarily.     

Direct conversion of methane to acetylene or syngas at room temperature using non-equilibrium pulsed discharge

Non-catalytic direct conversion of methane to valuable products was studied using non-equilibrium pulsed discharge under the conditions of ambient temperature and atmospheric pressure. Acetylene was produced with 95% selectivity and 52% methane conversion. An addition of oxygen, carbon dioxide and steam contributed significantly to suppress the carbon deposition and produced carbon monoxide as well as acetylene. Methane conversion increased with an increase in the pulse frequency while the product selectivity remained almost constant. The selectivity depended on the composition of the feed gas. The effect of the partial pressure of oxygen was examined, and it was found that the pulsed discharge would be able to produce synthesis gas by partial oxidation of methane. Carbon monoxide selectivity of 79% with methane conversion of 76% was obtained under the conditions of CH₄/O₂=25/25 cm³ min⁻¹, gap distance of 10 mm and the frequency of 45 Hz.     

Temperature profile in a two-stage fixed bed reactor for catalytic partial oxidation of methane to syngas

Detailed axial temperature distribution has been studied in a two-stage process for catalytic partial oxidation of methane to syngas, which consists of two consecutive fixed bed reactors with oxygen or air separately introduced. The first stage of the reactor, packed with a combustion catalyst, is used for catalytic combustion of methane at low initial temperature. While the second stage, filled with a partial oxidation catalyst, is used for the partial oxidation of methane to syngas. A pilot-scale reactor packed with up to 80 g combustion catalyst and 80 g partial oxidation catalyst was employed. The effects of oxygen distribution in the two sections, and gas hourly space velocity (GHSV) on the catalyst bed temperature profile, as well as conversion of methane and selectivities to syngas were investigated under atmospheric pressure. It is found that both oxygen splitting ratio and GHSV have significant influence on the temperature profile in the reactor, which can be explained by the synergetic effects of the fast exothermic oxidation reactions and the slow endothermic (steam and CO₂) reforming reactions. Almost no change in activity and selectivity was observed after a stability experiment for 300 h.     

Analyzing Biomass Conversion into Liquid Hydrocarbons

Variants of the Fischer–Tropsch producer-gas conversion into liquid hydrocarbons are analyzed under the assumption that thermodynamic equilibrium is attained in the reactions occurring in the biomass gasification. When the raw material is wood waste, the optimum variant of the process involves partial biomass oxidation by atmospheric oxygen with tail-gas recycling after the separation of liquid hydrocarbons. Before mixing with fresh producer gas, the hydrocarbons contained in the tail gas are reformed on a nickel catalyst.     

Separation of binary mixtures by dense membrane processes: influence of inert gas entrance under variable downstream pressure conditions

The influence of an inert gas on the separation performances of a dense polymeric membrane module working under partial vacuum on the downstream side, such as possibly encountered in gas permeation, vapor permeation or pervaporation, has been investigated through an experimental and theoretical study. A whole range of situations on the downstream side, covering ideal vacuum pumping (i.e. zero downstream pressure under leak free conditions) to inert gas sweeping under atmospheric pressure has been tested. A theoretical framework, previously developed for single permeant situation has been extended to the multicomponent case. The separation of methanol and 2-propanol by a dense silicone rubber membrane confirms the ability of this simple modelling strategy to offer quantitative predictions of the permeate composition under variable downstream pressure and inert gas flowrate conditions. Based on this observation, the implications of an inert gas contribution on pervaporation or gas separation operation are discussed, particularly in relationship to the global energy consumption of the system or to analytical devices making use of a gas sweep.     

天然气加压空气部分氧化——深冷除氮制合成氨原料气的生产工艺

本文针对我国以天然气为原料的小型合成氨厂采用的常压间歇蒸汽转化制气方法热效率低、能耗高等问题,提出采用加压空气部分氧化—深冷除氮的生产工艺改造这类小型氨厂。     

Role of the surface state of Ni/Al2O3 in partial oxidation of CH4

The effect of gas phase O₂ and reversibly adsorbed oxygen on the decomposition of CH₄ and the surface state of a Ni/Al₂O₃ catalyst during partial oxidation of CH₄ were studied using the transient response technique at atmospheric pressure and 700°C. The results show that, when the catalyst surface is completely oxidized under experimental conditions, only a small amount of CO and H₂ can be produced from non‐selective oxidation of CH₄ by reversibly adsorbed oxygen which is more active in oxidizing CH₄ completely than NiO via the Rideal–Eley mechanism and both the conversions of CH₄ and O₂ and the selectivities to CO and H₂ are very low. Therefore, keeping the catalyst surface in the reduced state is the precondition of high conversion of CH₄ and high selectivities to CO and H₂. The surface state of the catalyst decides the reaction mechanism and plays a very important role in the conversions and selectivities of partial oxidation of CH₄. During partial oxidation of CH₄, no oxygen species but a small amount of carbon exists on the catalyst surface, which is favorable for maintaining the catalyst in the reduced state and the selectivity of CO. The results also indicate that direct oxidation is the main route for partial oxidation of CH₄, and the indirect oxidation mechanism is not able to gain dominance in the reaction under the experimental conditions. This revised version was published online in July 2006 with corrections to the Cover Date.