The kinetics of oxidative desulfurization of diesel fraction with a hydrogen peroxide-formic acid mixture

The dependence of the oxidation rate of sulfur compounds on duration, oxidation temperature, and amount of the introducing oxidizer has been demonstrated with the straight-run diesel with a high initial sulfur content. The data for the oxidation rates of benzo- and dibenzothiophene homologues depending on the amount and the position of alkyl substituents in them during competing oxidation reactions of different diesel components have been obtained. The effective rate constants have been calculated for the oxidation reactions of the sulfur compounds during the oxidative desulfurization. The mechanism of the interaction of diesel sulfur compounds with the oxidant is proposed.     

Ultrasound assisted catalytic oxidative desulfurization of diesel oil using CdO nanoparticles

In this paper, sol-gel auto-combustion method is used to synthesize CdO nanoparticles. The synthesised sample is characterized for its size and structure using X-Ray diffraction (XRD) and scanning electron microscopy (SEM) techniques. And some molecular groups containing in the nanoparticle are detected by Fourier transformer Infra Red (FT-IR). Then, the sample is used to remove the organic sulfur from hydrogenation desulfurated diesel under ultrasonic condition. The influence parameters including catalyst dosage, oxidant dosage, oxidation temperature, oxidation time and extracting times are been researched. The obtained result indicates that under the optimal condition, the desulfurization degree can be reached 72.7%.     

Production of diesel fractions by catalytic cracking of vacuum gas oil and its mixture with cottonseed oil under the influence of a magnetic field

The influence of the 0.4?T magnetic field on catalytic cracking of the vacuum gasoil and its mixture with 5% cottonseed oil was evaluated. Magnetic field intensity excites aromatic resins existing in the vacuum gasoil and causes more effective cracking. Catalytic cracking was conducted using commercial X-zeolite fluid catalytic cracking catalyst and reaction products, especially gasoline and diesel fractions were analyzed in detail. Magnetic field increased the yield of the diesel fraction from 7 to 33% and enriched its composition with aromatic hydrocarbons while opposite effect was observed in gasoline. Cracking mechanisms in formation of gasoline and diesel range hydrocarbons were briefly discussed.     

汽油和柴油脱硫技术进展

对目前清洁燃料油的生产技术进行了概述。随着环境保护意识的增强，世界各国将实施更加严格限制燃料油中硫含量的新规定，为此进一步开展清洁燃料油生产技术具有重要的意义。结合现有的燃料油脱硫技术，深入开展催化吸附脱硫、生物脱硫技术及组合脱硫技术应当成为燃料油脱硫技术的研究重点。     

Ultrasound assisted photocatalytic oxidative desulfurization of model diesel fuel

Ultrasound assisted photocatalytic oxidation technology is an efficient and gentle technology to remove the organic sulfur from diesel. The influence parameters of catalytic oxidation phase include catalyst dosage, reaction temperature, oxidation time, hydrogen peroxide to diesel fuel ratio and time of the extraction process. Furthermore, the comparison of the results under two conditions of ultrasound irradiation and mechanical agitation are also specially examined. The obtained results indicate that under the optimal condition, ultrasound assisted oxidative desulfurization (UAOD) is more efficient for sulfur removal which the desulfurization degree can be reached 99.47%.     

Ozone-assisted oxidative desulfurization of light oil fractions

A catalytic system for oxidative desulfurization has been created, which is a transition metal salt bearing an organic ligand and capable of forming an active oxidative complex in the interaction with ozone and further oxidizing sulfur compounds present in fuel followed by the adsorption of the oxidation products on silica gel. In this case, a direct contact of ozone with the fuel is avoided, making the process safer. The effect of the reaction and ozonation conditions on the desulfurization process has been studied. Total sulfur content was decreased to 180 ppm for the straight-run gasoline fraction and to 900 ppm for the diesel fraction.     

焦化柴油氧化脱硫脱氮工艺条件优化

研究了工艺条件对焦化柴油氧化萃取脱硫脱氮效果的影响。结果表明,氧化体系选用双氧水溶液(H2O2质量分数为30%)和甲酸,以磷钨酸为催化剂,以糠醛为萃取剂,在氧化温度为70℃,恒温回流搅拌时间为60 min,V(氧化体系)/V(焦化柴油)为0.4,V(甲酸)/V(双氧水溶液)为0.5,磷钨酸用量为0.20 g/L,采用二级萃取的优化工艺条件下,可将焦化柴油中硫的质量分数由817.563×10-6降至45.613×10-6,氮质量分数由734.577×10-6降至13.620×10-6。     

过氧化叔戊醇对柴油氧化脱硫的工艺优化

以过氧化叔戊醇（TAHP）为氧化剂、MoO3/D 113为催化剂、N-甲基吡咯烷酮（NMP）为萃取剂,对焦化柴油进行氧化-萃取脱硫实验,考察了氧化温度、氧化时间、氧化剂用量、催化剂用量、萃取剂用量等工艺条件对脱硫率的影响.结果表明,最适宜的氧化-萃取脱硫工艺条件如下:氧化温度90 ℃,氧化时间2.5h,氧化剂/柴油（摩尔比）4,催化剂用量0.1g,萃取剂/柴油（体积比）1;在此条件下,柴油中硫化物的脱除率为96.8％,含硫量降至29.7 μg/g,柴油的回收率达98.6％.     

Hydrogen peroxide oxidative desulfurization of model diesel mixtures using azacrown ethers

Hydrogen peroxide oxidative desulfurization of model diesel fuel mixtures in the presence of azacrown ethers and their complexes with niobium pentachloride at 40–80°C has been studied. It has been found that the use of complexes of azacrown ethers with NbCl₅ leads to a decrease in the total sulfur content in the model mixtures to 13% of the initial amount. The structure of the azacrown ether used has little effect on the extent of desulfurization of the model mixture.     

Effect of various sono-oxidation parameters on the desulfurization of diesel oil

The influences of ultrasonic intensity, H₂O₂ concentration, ratio of H₂O₂ to oil and the addition of Fenton reagent on the oxidative desulfurization of diesel oil under ultrasonic irradiation were investigated. It was observed that the oxidative desulfurization of diesel oil fitted pseudo-first-order kinetics under our experimental conditions. Increasing the ultrasonic intensity increased the oxidative desulfurization efficiency of diesel oil. The addition of H₂O₂ enhanced the ultrasonic oxidative desulfurization efficiency of diesel oil. The sono-oxidation treatment in combination with Fenton reagent showed a synergistic effect for diesel oil desulfurization. The catalytic oxidative desulfurization process under ultrasonic irradiation process on diesel oils is an efficient and promising method.     

柴油吸附脱硫活性炭改性吸附剂研究

研究了用不同金属离子以及糠醛、糠醇、浓硫酸、浓硝酸对活性炭进行改性对活性炭吸附剂对FCC柴油和由正癸烷和二苯并噻吩(DBT)组成的模拟柴油的脱硫率的影响。实验结果表明:金属离子改性中Fe离子改性活性炭脱硫率好;活性炭浸涂糠醛、糠醇也可以提高吸附脱硫性能;浓硫酸、浓硝酸氧化可以增加活性炭表面酸性基团的量,改进脱硫性能,浓硫酸优于浓硝酸。进行了活性炭复合改性实验,结果表明,浓硫酸氧化后再进行Fe改性,脱硫率最高,吸附DBT模型物的脱硫率可达到100%。     

Reduction of sulfur content in shale oil by oxidative desulfurization

The oxidative desulfurization of shale oil obtained by thermal extraction of organic matter from shale rock using an oxidative catalytic system composed of hydrogen peroxide, a molybdenum salt, and acids of different natures has been studied. It has been shown that the application of this method in combination with extraction of the oxidation products of organic sulfur compounds makes it possible to remove up to 94% of total sulfur from the synthetic oil.     

Characterization of light diesel fraction obtained from upgraded heavy oil

In this study, the role of a low-cost catalyst (activated molasses soil) over the hydrocarbon distribution of the light diesel (or distillate) fraction of the pre-upgraded heavy crude oil (Bati Raman) was examined in detail. The low-cost catalyst showed a strong impact on the hydrocarbon distribution of the light diesel fuel fraction. The physicochemical characteristics such as hydrocarbon group distribution, density and kinematic viscosity of the light diesel fuels obtained from the upgraded heavy oil indicated a proper consistency with those having the commercial diesel fuels. As a result, it was revealed that the low-cost material could be successively used in the heavy oil upgrading to obtain the light diesel fuels.     

汽柴油深度脱硫方法及发展现状

阐述了当前国内外对汽柴油中硫含量的要求以及汽柴油中的硫化物特点,结合这些特点对吸附脱硫、萃取脱硫、膜分离、生物技术脱硫、络合沉淀法和催化氧化法等几种深度脱硫方法进行了论述,并且提出了未来汽柴油深度脱硫技术的发展方向.     

Study on a new desulfurization method based on imitating ionic liquids for light diesel oil

A simulated light oil consisting of model sulfur compounds of benzothiophene (BT), dibenzothiophene (DBT) and 4,6-dimethyldibenzothiophene (4,6-DMDBT) and straight-run light diesel oil fractions as solvent was employed for desulfurization tests imitating silver-salt method for ionic liquids (ILs). Under the conditions of a nitrogen atmosphere, reaction temperature of 303 K, reaction time of 24 h, the effects of different alkylating agents and amount of agent on the sulfur removal were investigated in more details. The results showed that when ratio of bromoethane (CH₃CH₂Br) to sulfur is 80: 1 (mol/mol) and ratio of potassium tetrafluoroborate (KBF₄) to sulfur 30: 1 (mol/mol), the desulfurization yield were 72.6%.     

焦化柴油催化氧化吸附脱硫工艺条件优化

以磷钼酸季铵盐为催化剂,三氟乙酸为氧化剂,糠醛为萃取剂,采用催化氧化-萃取吸附组合工艺对焦化柴油进行脱硫处理。结果表明,在反应温度为60℃,氧化剂用量（V（氧化剂）/V（焦化柴油））为0.2,催化剂用量（m（催化剂）/V（焦化柴油））为8 g/L,反应时间为60 min,萃取剂用量（V（萃取剂）/V（焦化柴油））为1.0,萃取时间为30 m in的最佳工艺条件下,焦化柴油的硫质量分数可从1.05×10-3下降为42×10-6。     

Reasons for low heavy vacuum gas oil yield in vacuum distillation of residual fuel oil

Calculations are made of the heat balance of the vacuum column K-101 of the VDM-2 plant of LUKOIL Neftokhim Burgas AD, which made it possible to disclose the reasons for decline in heavy vacuum gas oil yield with increase in plant load and to discard the hypothesis that the reason for this is perforating of the plate from which the gas oil is withdrawn. It is shown that the reflux yield cannot be increased and the heat required for condensation of the heavy vacuum gas oil contained in the residual fuel oil cannot be removed if there is hydraulic resistance in the lower circulating reflux line. Translated from Khimiya i Tekhnologiya Topliv i Masel, No.3, pp. 19 – 22, May – June, 2009.     

Extension of gas adsorption models to liquid diesel fuel desulfurization: Validity and predictability

Desulfurization of diesel fuel is simulated in a fixed-bed adsorption column. Researchers have paid less attention to models that describe and predict liquid phase adsorption. Hence, the ability of five widely used models which were originally developed for gas adsorption (Zhang–Cheng, Clark, Thomas, Bohart–Adams, and Wolborska) to simulate and predict the fuel desulfurization breakthrough curve is investigated. Afterward, the best model is chosen to predict the breakthrough curve in different flow rates and bed depths. An industrial scale-up with a real refinery flow rate using the appropriate model has been done. The results are in good agreement with the reported ones.