Oxidative Desulfurization of Fuel Oil with Hydrogen Peroxide Catalyzed by Keggin-type Polyoxotungstate in a DC Magnetic Field

Abstract

The oxidation of sulfur-containing compounds was conducted in a DC magnetic field-assisted system, composed of model compound or diesel, 30 wt% hydrogen peroxide, and an iron mono-substituted Keggin-type heteropolytungstate [(C₄H₉)₄N]₄ [PW₁₁Fe(H₂O)O₃₉] catalyst. By combining oxidative desulfurization (ODS) in a magnetic field and acetonitrile extraction, when magnetic field intensity was at 17.3 mT, the removal efficiency of the model compound dibenzothiophene (DBT) in petroleum ether with 1,000 ppm S can reach 98% at 70°C within 30 min with O/S ratio = 3 and catalyst dosage 5%, with 2% increase over that without magnetic field assistance. Under the same reaction conditions, the sulfur level of diesel oil was reduced from 5,647 to 508 ppm. This shows that the DC magnetic field facilitates the oxidation of sulfur-bearing compounds, which allowed greater sulfur removal efficiency under milder reaction conditions.     

Modeling crude oil gasification

Abstract

The characteristics of CO₂-gasification of crude oil under steady-state condition were studied using a simulator. The model was developed using the minimization Gibbs free energy minimization. The effects of reactor temperature and CO₂/crude oil ratio on gas composition and lower heating value (LHV) of the produced syngas were investigated. As a result, the maximum LHV was obtained at a CO₂/crude oil ratio of 0.1 and gasification temperature of 800?°C.     

Evaluation of interfacial tension between ASP solution and crude oil from B oil field

The interfacial tension (IFT) between alkali-surfactant-polymer (ASP) solution and crude oil is an important parameter for evaluating the feasibility of the ASP flooding for an oil field. The IFT between six series of ASP solution and crude oil from B oil field were measured at 65°C. Each series of ASP solution was composed of NaOH or Na₂CO₃, one of the three kinds of surfactants (S1, S2, and S3), and polymer FT60. The concentration of FT60 and surfactant were 1500 and 2000 mg/L, respectively. The research results show that the IFT between ASP solution and crude oil is ultra-low in the NaOH-FT60-S2 series and NaOH-FT60-S3 series and the best concentration of NaOH is 4000 mg/L and 8000 mg/L, respectively. NaOH-FT60-S2 series is more suitable for B oil field. The IFT between ASP solution and crude oil is ultra-low in the Na₂CO₃-FT60-S2 series and the best concentration of Na₂CO₃ is 4000 mg/L.     

Investigation of non-Newtonian flow characterization and rheology of heavy crude oil

The heavy crude oil exhibits a non-Newtonian shear thinning behavior over the examined shear rate. The viscosity of the heavy crude oil decreases about 15.6% when the temperature increased from 30 to 60°C. Heavy crude oil was blended with the aqueous solution of surfactant and saline water in different volumetric proportions of NaCl, and Na₂CO₃ solution mixtures. The addition of 50% of the mixture to the heavy crude oil causes a strong reduction in the viscosity, about 67.5% at 60°C. The heavy crude oil fits the Power law model since it has the lowest average absolute percent error of 0.0291. The flow behavior index of the heavy crude oil reaches a value of 0.9305 at a temperature of 30°C and it increases to 0.9373 when the temperature raises 60°C, while the consistence coefficient decreases from 2.8811 to 2.3558.     

Catalytic Neutralization Method for Naphthenic Acid Removal in Crude Oil by Alumina Supported Ca and Ba Catalysts

The presence of naphthenic acids in crude oils has caused a major corrosion problem to the production equipment, storage and transport facilities in the petroleum industry. To overcome this problem, catalytic neutralization method will be investigated on real petroleum crude oil sample with various parameters study such as the type of basic chemical used, dosing amount, type of catalyst, catalyst calcination temperature, and catalyst ratio of basic metal and dopant. Potential catalyst was characterized by XRD, NA, and TGA-DTA for its physical properties. Cu/Ca(10:90)/Al₂O₃ catalyst with calcination temperature of 1000°C was an effective catalyst for all three types of crude oil. In the presence of catalyst, all three types of crude oil samples showed enhancement in the removal of naphthenic acid.     

Distribution and treatment of harmful gas from heavy oil production in the Liaohe Oilfield,Northeast China

The distribution and treatment of harmful gas (H₂S) in the Liaohe Oilfield, Northeast China, were investigated in this study. It was found that abundant toxic gas (H₂S) is generated in thermal recovery of heavy oil. The H₂S gas is mainly formed during thermochemical sulfate reduction (TSR) occurring in oil reservoirs or the thermal decomposition of sulfocompounds (TDS) in crude oil. H₂S generation is controlled by thermal recovery time, temperature and the injected chemical compounds. The quantity of SO₄²⁻ in the injected compounds is the most influencing factor for the rate of TSR reaction. Therefore, for prevention of H₂S formation, periodic and effective monitoring should be undertaken and adequate H₂S absorbent should also be provided during thermal recovery of heavy oil. The result suggests that great efforts should be made to reduce the SO₄²⁻ source in heavy oil recovery, so as to restrain H₂S generation in reservoirs. In situ burning or desulfurizer adsorption are suggested to reduce H₂S levels. Prediction and prevention of H₂S are important in heavy oil production. This will minimize environmental and human health risks, as well as equipment corrosion.     

Source of Chang 10 crude oil in Zhidan area,Ordos Basin,China

Abstract

Numerous studies on the oil source of Chang 10 reservoir in the Zhidan area were undertaken until now, but still have no definite conclusion. Based on the comparisons and analyses of geochemical parameters between Chang 7 to Chang 9 source rocks and Chang 10 crude oil, it is found that the forming environments of the crude oil in the Chang 10 member are similar to Chang 7 and Chang 9 source rocks, as they occur both in weak reduction environments. C₃₀ hopane(C₃₀H), Ts, C₃₀ rearranged hopane(C₃₀*), Ts/C₃₀H and C₃₀*/C₃₀H range of two types of crude oil in the Chang 10 member are similar to those of Chang 7 and Chang 9 source rocks, respectively. The results show that the crude oil in the Chang 10 member is a mixed product of Chang 7 and Chang 9 source rocks.     

Experimental investigation of interfacial tension and oil swelling for asphaltenic crude oil/carbonated water system

The phenomenon of oil swelling at the oil-carbonated water (CW) system could be an important mechanism during the water alternating gas (WAG) injection process. Nevertheless, the study of the main mechanisms during water flooding (WF) is a complex topic that has not been well revealed so far, especially for asphaltenic crude oil (ACO) systems. Hence, the main goal of this experimental work is to determine the influence of carbon dioxide (CO₂) within the water phase in the interfacial tension (IFT) between water and crude oil for an extensive range of pressures between 400 psi and 2000 psi (i.e. 2.76–13.79 MPa), under two temperatures of 313.15 and 323.15 K (i.e. 40 and 50 °C) by axisymmetric drop shape analysis (ADSA) method. The experimental results demonstrate that the water/ CW and crude oil IFTs decline with time. The value of dynamic IFT (DIFT) between CW and crude oil decreased about 6 mN/m in comparison with the oil–water DIFT. As a result of the CO₂ solubility, the crude oil droplet swells with increasing pressure. When the temperature rises, the effects of increasing entropy phenomena and decline of liquids density is dominant compared to the solubility of CO₂. Thus, the volume of oil droplet increases with temperature, unexpectedly. In addition, as thetemperature increases the water/CW-Oil IFT is slightly reduced over a wide range of pressure evaluated. Nevertheless, there is a slight increase as the pressure increases for the water–oil system. According to the predicted results, interfacial tension of the CW-oil system declines with increasing pressure until the solubility of CO₂ is reached to a maximum value and then approximately remains changeless.     

重质油催化工艺多产乙烯过程中污染铁对催化剂性能发挥的影响

采用N2吸附容量法、BET、热重原位NH₃-TPD、吡啶吸附红外光谱(Py-IR)法分析了污染铁对重油制取乙烯专用催化剂性能发挥的影响。结果表明,有机铁污染催化剂微孔部分的比表面积和孔体积都有明显损失,低于200℃的NH₃-TPD脱附峰代表的弱酸中心损失约为26%。L酸点和B酸点的混合酸对重油催化制乙烯中甲烷、氢气的产生起到关键的作用。环烷酸铁污染后的催化剂沸石晶内酸性大量损失,预示在重油催化制乙烯工艺中有机铁污染催化剂中毒部分主要位于沸石晶内,而非外表面或微晶的孔口处;且原油中Fe³⁺比Fe²⁺更具有金属活性,表现出的氧化脱氢性能更为明显。在重油催化制乙烯工艺中,铁污染催化剂会导致氢气、焦炭的急剧增加,丙烯产率也会明显减少,而干气和汽油产率基本不受影响。     

High energy and low emissions from catalytic combustion of crude oil

Combustion technology has been investigated to effectively and economically heat and power generation. A kinetic model of crude oil combustion in presence of CaO as a catalyst was developed. Effects of CaO mass yield (ppm) on three main parameters including combustion carbon conversion efficiency, reaction temperature, and combustion efficiency were investigated. Results showed that the CaO has a significant effect on the decrease of CO₂, which is the most important greenhouse gas. It also found that the carbon conversion efficiency decreases as the CaO increases, although it is not considerable.     

Optimization of Oxidative Desulfurization of Dibenzothiophene Using a Coordinated Ionic Liquid as Catalytic Solvent

Abstract

Oxidative desulfurization (ODS) of dibenzothiophene (DBT) in n-octane with hydrogen peroxide/acetic acid using a quaternary ammonium coordinated ionic liquid (IL) (C₄H₉)₄NBr · 2C₆H₁₁NO as catalytic solvent has been studied. The ODS mechanism by coordinated ionic liquid [(C₄H₉)₄NBr · 2C₆H₁₁NO] was also carried out. The sulfur-containing compounds in model oil were extracted into ionic liquid phase and oxidized to their corresponding sulfones by H₂O₂. The effect factors for desulfurization of model oil were investigated in detail by means of monofactorial and orthogonal experiments (L₁₆(4)⁴). The results showed that the desulfurization efficiency of model oil could reach 98.6% under the optimal conditions of oxidation time, oxidation temperature, molar ratio of H₂O₂/sulfur (O/S), and volume ratio of model oil to coordinated ionic liquid were 30 min, 50°C, 16, and 1, respectively. The influences to the desulfurization efficiency of DBT decreased in the following order: volume ratio of model oil to coordinated ionic liquid (C₄H₉)₄NBr · 2C₆H₁₁NO (V_{model oil}/V_IL) > molar ratio of O/S > oxidation temperature > oxidation time, according to extreme analysis of the orthogonal test. The coordinated ionic liquid (C₄H₉)₄NBr · 2C₆H₁₁NO can be recycled 5 times without a significant decrease in desulfurization.     

枯草芽孢杆菌提高原油采收率的物模驱油实验

针对目前常规采油开采技术的限制和原油采收率较低等问题,本研究采用单因素法对一株从油污中分离的枯草芽孢杆菌(Bacillus subtilis 32811)代谢产生物表面活性剂的发酵条件进行优化并进行微生物驱油实验。优化条件实验确定了以葡萄糖为唯一碳源,最佳的无机培养基配方(g/L):ρ(C_6H_(12)O_6)30.0,ρ(NH_4NO_3)1.0,ρ(KH_2PO_4)4.1,ρ(Na_2HPO_4·12H_2O)14.3,ρ(MgSO_4)0.096,ρ(CaCl_2)0.0008,ρ(FeSO_4)0.0011,ρ(C_(10)H_(16)N_2Na_2O_8)0.0015。发酵液表面张力从65mN/m降至25mN/m。通过微生物对原油降解的物模驱油实验,得出原油出现乳化及原油重质组分含量明显降低的结果。物模驱油实验中分别注入发酵液及先注入微生物再注入无机培养液能提高原油采收率26.1%和31.4%。说明枯草芽孢杆菌有利于提高剩余油的采收率,具有良好的应用前景。     

Geochemistry,generation and maturation of the hydrocarbons at Wadi Al-Rayan oil field,Western Desert of Egypt

`The present work aims to study the organic chemistry, the generation and maturation of the hydrocarbons encountered at Abu Roash Formation, Wadi El Rayan oil field. The analysis of source rocks indicates the presence of two organic facies. The first is characterized by high total organic carbon of 0.93–3.39%, strongly oil-prone (Type II), and good potential for oil generation (pyrolysis S2 yields 4.54–23.26 mg HC/g rock and HI 488–705 mg HC/g TOC). The second attains good range of organic carbon from 0.90% to 1.57%, which is a mixed oil and gas (Type II–Type III) of fair hydrocarbon generation (pyrolysis S2 yield of 1.98–5.33 mg HC/g). The kerogen type consists of unstructured lipids and some terrestrial material. Plot of Pr/n-C17 versus Ph/n-C18 indicates that the crude oil was derived from mixed source rock, while the maturity profile assigns oil windows (0.6 R_o%) matching topmost of Abu Roash G Member.     

Downhole Upgrading of Extra-heavy Crude Oil Using Hydrogen Donors and Methane Under Steam Injection Conditions

Abstract

An extra-heavy crude oil underground upgrading process is described which involves the downhole addition of a hydrogen donor additive under steam injection conditions (280–315°C and residence times of at least 24-h). Laboratory experiments showed a 4° increase in the API gravity (from 9 to 12°) of the upgraded product, a two-fold reduction in the viscosity and, an approximately 8% decrease in the asphaltene content with respect to the original crude. Further increases on the temperature led to products with improved properties reaching 15°API at 315°C. It was found that the presence of the natural formation (catalysts) and methane (natural gas) is necessary to enhance the properties of the upgraded crude oil. From GC and GC-MS results a reaction pathway is proposed that involves hydrogen transfers from tetralin to the extra-heavy crude oil resulting in the formation of 1,2-dihydronaphthalene. This compound is then transformed into naphthalene, further upgrading of crude oil through hydrogen donation. The results of the experiments carried out in the presence and absence of the mineral formation and with an inert solid (SiC) strongly indicate that the former acts as a catalyst and not as a heat transfer matrix. Isotopic labeling studies (CD₄ and ¹³CH₄) give evidences that, most probably, methane is involved in the upgrading reactions.     

噻吩类化合物GC—PFPD分析方法的建立及应用

利用气相色谱仪(GC)与脉冲火焰光度检测器(PFPD)联机,通过一系列条件实验,建立了原油和烃源岩中噻吩类化合物的GC—PFPD分析方法。该方法能够检测出烃源岩和原油中低丰度的7个苯并噻吩类化合物、19个二苯并噻吩类化合物及其他含硫芳烃,检测质量优于GC—MS分析方法。该方法的应用结果表明:渤海湾盆地济阳坳陷原油和烃源岩噻吩类化合物中苯并噻吩系列含量很低,主要是二苯并噻吩系列化合物;且4个甲基二苯并噻吩的"V"字形分布并不是碳酸盐岩所固有的分布模式,咸水环境沉积的泥质岩同样具有"V"字形分布特征;另外,烃源岩中这4种化合物的不同分布模式受沉积环境和有机质热演化程度的双重影响。     

The Mild Oxidative Degradation of the Heavy Constituents in Viscous Crude Oils/Oil Sands and Its Prospect in Oil Recovery

Abstract

Viscous crude oils and oil sands are important energy resources, but it is difficult to exploit them due to the dominated heavy constituents such as asphaltenes. In this work, the mild oxidative degradation of the heavy constituents (oxidized by NaIO₄/NaH₂PO₄ and 30% H₂O₂/CH₃COOH) has been carried out. In the viscous oils, more than 45% asphaltenes has been degraded, and the asphaltenes are mainly chemically changed into the resin fractions, which is favorable to the stability of viscous crude oils. After the degradation, the total amount of extractable organic compounds from oil sands has been markedly increased than that of the blank experiment. The experimental results indicate that the mild oxidative degradation of asphaltenes can improve the physicochemical properties of the viscous oils and oil sands, which is particularly in favor of the exploitation of these energy resources.     

Calorimetric study approach for crude oil combustion in the presence of clay as catalyst

In this research, the effect of heating rate and different clay concentrations on light and heavy crude oils in limestone matrix was investigated by differential scanning calorimeter (DSC). In DSC experiments, two main distinct reaction regions were identified in all of the crude oil + limestone matrix + catalyst, known as low- and high-temperature oxidation respectively. It was observed that addition of clay to porous matrix significantly affected the thermal characteristics and kinetics of different origin crude oils. The Borchardt and Daniels and ASTM kinetic methods were used to determine the kinetic parameters of the samples. It was observed that activation energies generated for the high-temperature oxidation region for crude oil and crude oil + clay mixtures were in the range of 148–370 kJmol^?1 for the Borchardt and Daniels method and 51–253 kJmol^?1 for ASTM methods.     

Hydrothermal synthesis of unsupported MoS2 as catalyst for hydrodesulfurization of gas oil

Hydrothermal synthesis with ammonium heptamolybdate and thiourea as precursors was used to obtain an unsupported MoS₂ catalyst. The catalyst was obtained in sulfide state directly at mild reaction conditions (i.e., 180°C during 5 h). After catalyst was obtained, it was characterized through nitrogen physisorption, transmission electron microscopy, energy-dispersive spectroscopy, X-ray diffraction, and X-ray photoelectron spectroscopy. Catalytic evaluation was carried out in a batch reactor at 350°C, 55 bar of hydrogen pressure, 750 rpm, and 3 h of reaction time using straight-run gas oil (SRGO) as feedstock. A commercial CoMo/Al₂O₃ catalyst was used for comparison of activity. The synthesized catalyst was slightly more active toward SRGO hydrodesulfurization than commercial one keeping constant the sulfur removal after two runs.     

A laboratory investigation of carbon dioxide-enhanced oil recovery by focusing on CO2-oil physical properties

Carbon dioxide (CO₂) miscible flooding has become an important method in enhanced oil recovery (EOR) for recovering residual oil. In addition it may help in protection of the environment as (CO₂) is widely viewed as an important agent in global warming. Knowledge of the interactions between (CO₂) and reservoir crude oil is very critical for any (CO₂)-enhanced oil recovery (EOR) projects. This paper shows the effect of (CO₂) miscible flooding application for Egyptian oil fields by swelling studies. The swelling test is a laboratory simulation of the process of injecting gradually different percentage of (CO₂) gas into a reservoir containing under-saturated oil. The gas (injection solvent) can dissolve, causing the reservoir fluid to swell. This paper presents a summary of a wide range of laboratory tests conducted on ten different crude oils varying from 26.4 to 40.5 API. These were used to invested the use of (CO₂) and its effect on parameters such as viscosity, density, gas solubility and swelling factor as a function of pressure at temperature from 620.3 to 706.0?°R.     

Role of Mn/Al2O3 catalyst in deep oxidative desulfurization of diesel

Abstract

In this work, a series of supported manganese catalyst has been synthesized and utilized in oxidative desulfurization to remove 4,6-dimethyldibenzothiophene (4,6-DMDBT), dibenzothiophene (DBT) and thiophene. The influences of catalyst parameters were investigated including manganese precursors, manganese loading and calcination temperature in details. The synthesized catalyst was characterized by scanning electron microscopy (SEM), N₂ adsorption/desorption and X-ray diffraction (XRD) techniques. 90.2% of 4,6-DMDBT, 98.5% of DBT and 95.5% of thiophene conversion were achieved under mild operational conditions using 3Mn(NO₃)₂/Al₂O₃ at 500?°C calcination temperature. A slight decrease in desulfurization activity was observed after Mn/Al₂O₃ catalyst being used in five cycles ODS.