Thermal dissolution of combustible shale from the Dmitrievskoe deposit in benzene under supercritical conditions

The results of the thermal dissolution of combustible shale in benzene under supercritical conditions in a flow system are reported. It was found that the conversion of the organic matter of combustible shale into liquid products increased by a factor of 2.2 as the solvent pressure was increased from 5 to 15 MPa; in this case, the fraction of high-molecular-weight products in them increased by a factor of 2.     

Thermal solution of Kashpir shale in pressurized benzene under supercritical conditions

The results of the thermal solution of oil shale in benzene in a flow unit under supercritical conditions are reported. It was found that the conversion of shale organic matter into liquid products increased by a factor of 2.5 with an increase in the solvent pressure from 5 to 15 MPa.     

Thermal dissolution of mechanically activated Barzas sapromyxite coal with benzene under supercritical conditions

The results of the thermal dissolution of Barzas sapromyxite coal in benzene under supercritical conditions in a flow system are reported. It was found that the mechanical pretreatment of coal under intense impact bending conditions resulted in an increase in the yield and a change in the group composition of the liquid products: in the high-temperature region of the process, the concentration of high-molecular-weight components (preasphaltenes, asphaltenes, and resins) increased.     

加压和超临界条件下乙醇分子的缔合

引言 在化学和化工领域,分子扩散系数是过程设计和装置优化所需的基本数据之一[1].乙醇作为一种高效绿色溶剂,具有良好的溶剂性能和比较温和的临界温度、临界压力(Tc=514.3 K,pc=6.38MPa),在食品、医药和化工等领域有巨大的应用空间[2].     

Continuous synthesis of castor oil ethyl esters under supercritical ethanol

The transesterification of castor oil under supercritical ethanol using a catalyst-free continuous process was investigated. The effect of water concentration on the reaction medium, reaction temperature, pressure, and substrates flow rate were studied. A maximum ester content of 74.2% was achieved when the reactor was operated at 573 K, 20 MPa, substrates flow rate of 0.8 ml min⁻¹, and 5 wt% water concentration in the alcohol. The ester content of the product increased with the operation temperature, but after certain temperature level the converse effect was observed. This adverse effect was attributed to oil degradation, which increased to 88.7% at 648 K (at the flow rate of 0.8 ml min⁻¹). A favorable effect on ester content was observed when the water concentration was increased, unlike the effect of water on the conventional alkali-catalyzed process.     

Microwave-mediated non-catalytic transesterification of algal biomass under supercritical ethanol conditions

A novel integrated approach has been proposed to convert lipid-rich, dry algae (Nannochloropsis salina) into fatty acid ethyl esters (FAEE) under microwave-mediated supercritical ethanol (MW-SCE) conditions with a non-catalytic transesterification approach. This process enables simultaneous extraction of lipids from algal biomass and conversion/transesterification of them into algal biodiesel in a relatively short reaction time, which may reduce energy consumption versus traditional processes due to simplified separation and purification steps. High conversion rates can be possible when the extractive-transesterification of algal biomass is performed near-critical or supercritical conditions. The use of passive heating elements made of silicon carbide (SiC) to aid the microwave-mediated heating process at higher temperatures is also described. Experimental runs were designed to optimize the process parameters to evaluate the effect on the algal biodiesel under controlled power conditions. The algal biomass characterization and algal biodiesel analysis were performed using various analytical instruments such as FTIR, SEM-EDS, TGA and GC–MS. It was demonstrated in this work that this direct conversion technique has the potential to provide an energy-efficient and economical route for algal biodiesel production.     

Acid dissolution of mineral matrix in Green River oil shale

The mineral matrix in Green River oil shale was partially removed by treatment with dilute HCl. The major ionic species in the solution from acid treatment (AT) were identified as Na⁺, Al³⁺, Fe²⁺, Mg²⁺, and Ca²⁺. The ion yields expected from reaction stochiometry, gravimetric analyses and comparison of calculated CO₂ yields with measured levels were consistent with the fact that Na⁺ and Al³⁺ originated primarily from analcite: Fe²⁺ and Mg²⁺ from dolomitic ankerite and Ca²⁺ from both dolomitic ankerite and calcite. Temperature and shale particle size were important parameters in the efficacy of AT. An increase in temperature and a decrease in particle size increased the rate of mineral dissolution. Fe²⁺ showed an anomalous trend in that the rate initially declined with increasing temperature after which it showed the usual increase with temperature. The kinetics of ion build-up in the solution from AT were analysed in detail for the case of Al³⁺. The Arrhenius expression was found to be valid only for finer particle sizes (e.g., ?35, +45 US mesh shale). A simple model is finally presented to account for the combined effect of temperature and shale particle size on mineral dissolution rates.     

Alkylation of benzene with propene over HBeta zeolites near supercritical conditions

The alkylation of benzene with propene to produce cumene over HBeta zeolites was carried out near supercritical conditions, where the reaction conditions were determined with considering the changes in the critical properties of reacting mixture along with the reaction extent. The results demonstrate that the reaction behaviour, especially the catalyst lifetime is sensitive to the reaction conditions. Catalysts deactivate much more rapidly when the reactions are carried out under such conditions far from the critical region of the reacting mixture, while they exhibit much longer lifetimes under the conditions near the critical region of the reacting mixture (290–310 °C, about 5.7 MPa). Performing the alkylation of benzene with propene on HBeta zeolites under supercritical conditions rather than in gas or liquid phase can be an interesting option for increasing throughput and prolonging catalyst lifetime; however, the reaction conditions should be determined according to the critical properties of reacting mixture along the reaction course.     

Thermal cracking of black oil fuel in a mixture with shale

The results of studies performed for the development of a new process of the thermal cracking of tar as a suspension with ground Baltic oil shale in order to obtain motor fuel components are reported. The experimental results suggest undoubted advantages of the process over industrial thermal cracking because the deep degradation of tar (the yields of a gasoline fraction with bp to 180°C, middle distillates with bp of 180–360°C, and feedstock for catalytic cracking with bp of 360–520°C were ~12, 43–44, and ~15–16 wt % on an initial tar basis) was achieved upon the single-stage processing of the raw material under relatively mild conditions (5 MPa, 425°C, and a feed space velocity of 1.0 h⁻¹). The resulting coke-like products and V and Ni contained in the raw material were deposited on the mineral matter of shale and removed from the reaction zone with the liquid products of the process.     

超临界条件下辽河稠油高软化点沥青颗粒的制备

在梯级分离实验装置上,以正戊烷为溶剂,在压力为4.0～7.0 MPa、温度为155～170℃的条件下,讨论压力、温度变化对辽河稠油减渣脱油沥青收率、脱油沥青颗粒分布的影响.压力增加,脱油沥青的收率减小;温度升高,脱油沥青的收率增大.随着压力的增加,50、40、30目颗粒的质量分数均减小,大于50目颗粒的质量分数增大.随着温度的升高,50、40、30目沥青颗粒的质量分数均增大,大于50目沥青颗粒的质量分数减小.在所得的颗粒中大于50、50、40、30目脱油沥青颗粒的质量分数依次减小,其中大于50目小颗粒的质量分数大于67%.得到了沥青收率与沥青颗粒分布的关系.随着沥青收率的增加,大于50目小沥青颗粒的质量分数减小,50目与小于50日较大沥青颗粒的质量分数增大.大于50目沥青颗粒质量分数与沥青收率的定量关系为:Y=114.9502-1.7118X,R=0.9585.扫描电镜(SEM)的分析结果表明:造粒得到的沥青颗粒为多孔性颗粒,由团聚形成的不规则较大颗粒和破碎得到的不规则小颗粒组成.     

Coal gasification with water under supercritical conditions

The conversion of an array of coal particles in supercritical water (SCW) was studied in a semibatch reactor at a pressure of 30 MPa, 500–750°C, and a reaction time of 1–12 min. The bulk conversion, surface conversion, and random pore models were used to describe the conversion. The quantitative composition of reaction products was determined, and the dependence of the rate of reaction on the degree of coal conversion, reaction time, and reaction temperature was obtained on the assumption of a first-order reaction and the Arrhenius function (E = 103 kJ/mol; A ₀ = 7.7 × 10⁴ min^?1). It was found that the gasification of coal under SCW conditions without the addition of oxidizing agents is a weakly endothermic process. The addition of CO₂ to SCW decreased the rate of conversion and increased the yield of CO. It was found that, at a 90% conversion of the organic matter of coal (OMC) in a flow of SCW in a time of 2 min, the process power was 26 W/g per gram of OMC.     

油页岩制油技术中的红外测温研究

针对油页岩制油气反应炉炉内温度场的分布、变化及反应炉布料图像的实时监测问题,提出一种基于红外测温和红外图像处理的反应炉温度场检测方法,探索反应炉炉内温度场与炉外温度场之间的变化关系和变化机理,揭示反应炉内的温度变化规律,实现对油页岩反应炉不同位置温度场变化的实时监控。通过反应炉不同位置、时段温度场的分析和再现,实现对油页岩及相关物料的最佳优化利用,达到对现有工艺条件、工艺过程进行有效监控和改进,实现油页岩反应炉温度检测的自动化,温度分析处理的及时化、可视化。     

桦甸油页岩的二级萃取溶解行为

以吉林桦甸油页岩为研究对象,通过二氯甲烷、石油醚两级萃取,对油页岩原矿、两级萃余物进行SEM扫描,对二氯甲烷萃取液、石油醚萃取液进行GC/MS检测,研究桦甸油页岩在两级溶液的溶解行为以及各级萃余物表面物理形貌。结果表明,随着萃取的加深,油页岩颗粒相对光滑的片层结构逐渐消失,颗粒粒径趋于细小,表面沟壑逐渐增多,后级萃取时液固接触面积增加。二氯甲烷和石油醚对油页岩中烷烃溶出能力较强。两级萃取物组分主要由C15～C28饱和烷烃构成。溶剂萃取法可以有效地提取油页岩中一类或相似的化合物群,对研究油页岩构成及提取高经济价值成分有重要意义。     

Application of response surface methodology to extract yields from stinging nettle under supercritical ethanol conditions

Response surface methodology was employed using a central composite design of experiments to optimize experimental conditions for stinging nettle extract yields under supercritical ethanol conditions. The following independent variables were investigated: extraction temperature, extraction time and plant concentration. The most significant factor was found to be the extraction temperature. A correlation coefficient was estimated to be 0.94, which demonstrates the effectiveness of the model. The values of the parameters in optimized conditions for the stinging nettle extract yield included an extraction temperature of 335 °C, an extraction time of 87 min, and a plant concentration of 9.A subsequent validation experiment was carried out at the optimal conditions. The validation experiment showed that the actual and predicted values for the stinging nettle extract yields were 45.3 and 42.7 wt%, respectively. The stinging nettle extracts consisted of a collection of compounds including fatty acid esters (FAE), phenols, indoles, and nitrogen containing compounds.     

Electrochemical dissolution of tungsten under pulsed conditions

Limiting diffusion currents for the anodic dissolution of a tungsten rotating disc electrode in alkaline solution under rectangular current pulses have been determined experimentally. These currents were calculated by use of approaches developed by Ib1, Cheh, and Chin. Experimental and calculated results were compared. It is shown that the use of bipolar voltage pulses enhanced the anodic dissolution of tungsten in alkaline medium.     

废弃油脂超临界法制备生物柴油研究

以废弃油脂为原料,利用超临界法制备生物柴油.通过单因素实验及正交实验研究了醇油摩尔比、反应压力、催化剂用量、反应时间、反应温度等因素对生物柴油产率的影响.结果表明,在实验范围内各影响因素对生物柴油产率作用的大小依次为:反应温度>反应压力>催化剂用量>反应时间>醇油摩尔比.废弃油脂超临界法制备生物柴油的最佳工艺条件为:反应温度240℃,反应压力10MPa,反应时间6min,催化剂用量0.06%,醇油摩尔比40/1.在此条件下,生物柴油产率达到99.37%.     

油页岩含氧低温载气干馏过程实验

油页岩干馏生产页岩油是油页岩的主要加工利用方式。为降低油页岩干馏所需热载气温度,以延长载气预热器使用寿命并实现节能操作,本文向热载气中掺入一定比例氧气,对含氧低温载气情况下的油页岩干馏过程进行了研究。测定了油页岩在含氧气体氛围中热解时的反应器床层升温特性,对气液相产物组成进行了分析并与无氧干馏产物进行了比较。结果表明,含氧低温载气干馏过程能够通过载气中的氧气与油页岩反应产生的热量使油页岩达到其干馏所需要的温度,页岩油收率及其成分与无氧高温载气干馏过程接近、而轻组分含量更高,并且含有更多的具有O—H键和C==O键官能团的化合物。本文研究结果为油页岩干馏生产页岩油提供了一种新的技术方法,具有较好的工业应用前景。     

Pyrolysis of oil shale in supercritical toluene: Reaction mechanism and role of hydrogen

Oil shale from the Stuart A deposit in Queensland, Australia has been pyrolysed in supercritical toluene in the presence and absence of gas-phase molecular hydrogen. Data have been collected in a 300-cm³ stirred tank autoclave, at a nominal residence time of 1 h, temperatures of 698 and 733 K, and 14.43 MPa total pressure (at temperature). Results for conversion of organic carbon to oil have been computed based on a carbon balance on the reaction system. The data have shown toluene to be an excellent dense-gas medium for production of shale oil from oil shale. Carbon conversions and oil yields of 86% and 95%, respectively, were achieved in the presence of gas-phase molecular hydrogen. Carbon conversions were severely depressed in the absence of hydrogen, clearly indicating the need for hydrogen activity in order to obtain high oil yields. An overall oil yield of 160% of Fischer Assay was achieved at a relatively low hydrogen consumption and moderate operating conditions.     

油页岩有机质的逐级热溶解聚及产物特性

依兰油页岩有机质经过四氢萘逐级热溶解聚,热溶解聚物分别经过GC-MS检测并归纳分类,并结合热溶解聚残渣的FT-IR和¹³C NMR分析结果,旨在从分子水平上揭示依兰油页岩有机分子结构特征。结果表明,依兰油页岩有机质经过200~400℃逐级热溶解聚后,200、300、350、375和400℃温度条件下逐级热溶解聚物的收率分别为8.8%、9.9%、18.5%、19.2%和23.4%,总收率达79.8%。在可溶性组分中,脂肪烃化合物占比为36.9%（其中直链烷烃27.4%,支链烷烃8.7%）,酚/醇类占比为5.5%,芳香烃占比为32.0%,酮类占比为12.7%,醚/酯类占比为5.4%,其他化合物占比为7.5%。呈现脂肪烃>芳烃化合物>酮类>酚/醇>酯/醚的规律分布状态,其中27.4%直链烷烃中碳数分布在14~30并在C₁₆和C₂₆呈现两个峰值。     

Composition of the products of the supercritical benzene extraction of combustible shale from the Kashpirskoe deposit

A change in the group composition of the liquid products of the supercritical fluid extraction of combustible shale under nonisothermal conditions at various solvent pressures was found. As the solvent pressure was increased, the yield of liquid products was found to increase mainly at the expense of high-molecular-weight substances (preasphaltenes and asphaltenes).