燃料油吸附脱硫反应机理及吸附剂研究进展

阐述了吸附脱硫过程的反应机理,对多种吸附剂包括金属氧化物、沸石分子筛、介孔材料、金属有机骨架化合物、碳基材料等的研究进展进行了综述,并对比了各种吸附剂性能的优缺点。指出今后研究方向是采用低成本路线合成比表面积大,吸附容量高的吸附剂,且其对燃料油中的硫化合物选择吸附性要高,再生后吸附能力下降最小。     

Optimization of dispersed carbon nanoparticles synthesis for rapid desulfurization of liquid fuel

Stringent regulations and environmental concerns make the production of clean fuels with low sulfur content compulsory for the petroleum refining industry. Because of ease of operation without high energy consumption, the adsorption of sulfur compounds seems the most promising process. Central composite design was used to optimize parameters influencing the synthesis of dispersed carbon nanoparticles (CNPs), a new class of sorbents, in order to obtain an excellent adsorbent for desulfurization of liquid fuel. The optimized dispersed CNPs, which are immiscible in liquid fuel, can effectively adsorb different benzothiophenic compounds. Equilibrium adsorption was achieved within 2 min for benzothiophene, dibenzothiophene, and 4,6-dimethyldibenzothiophene with removal efficiency values of 75 %, 83 %, and 52 %, respectively. The rate of desulfurization by the prepared CNPs in the present work is seven times higher than the previously reported CNPs. Optimized CNPs were characterized by different techniques. Finally, the effect of the mass of CNPs on the removal efficiency was studied as well.     

Efficient desulfurization of gasoline fuel using ionic liquid extraction as a complementary process to adsorptive desulfurization

The extractive desulfurization of a model gasoline containing several alky]thiols and aromatic thiophenic compounds was investigated using two imidazolium-based ionic liquids(ILs).1-butyl-3-methylimidazolium tetrachloroaluminate,and l-oetyl-3-methylimidazolium tetrafluoroborate.as extractants.A fractional factorial design of experiments was employed to evaluate the effects and possible interactions of several process variables.Analysis of variance tests indicated that the number of extraction steps and the IL/gasoline volume ratio were of statistically highly significant,but none of the interactions were significant.The results showed that the desulfurizalion efficiency of the model gasoline by the ILs could reach 95.2%under the optimal conditions.The optimized conditions were applied to study the extraction of thiophenic compounds in model gasoline and several real gasoline samples:the following order was observed in their separation:benzothiophene > thiophene > 3-methylthiophene > 2-melhylthiophene.with 96.1%removal efficiency for benzothiophene.The IL extraction was successfully applied as a complementary process to the adsorptive desulfurization with activated Raney nickel and acetonitrile solvent.The results indicated that the adsorptive process combined with IL extraction could provide high efficiency and selectivity,which can be regarded as a promising energy efficient desulfurization strategy for production of low-sulfur gasoline.     

Adsorptive desulfurization and denitrogenation of model fuel by mesoporous adsorbents (MSU-S and CoO-MSU-S)

Adsorption of heterocyclic sulfur- and nitrogen-containing compounds by mesostructure adsorbent (MSU-S) and its modified form with cobalt oxide is studied using model fuel. The results of characteristic tests (XRD, N₂ adsorption–desorption, FTIR, and SEM) indicate that CoO impregnation causes a negative impact on mesoporous structure, crystalline phase, and particle shape along with a positive effect on surface ion exchange. CoO modification increased the adsorption loadings of DBT and BT to about 33.6% and 45.7%, respectively. For nitrogen compounds adsorption with the model fuel, adsorption loadings of quinoline and carbazole increase by 6.7% and 8.6%, respectively. Data fitting for carbazole, DBT, and BT is achieved better by the Langmuir model than the Freundlich model, and the data of quinoline fitted very well to the Freundlich model for CoO-MSU-S.     

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.     

Catalyst for desulfurization of high-end-point diesel fuel

Translated from Khimiya i Tekhnologiya Topliv i Masel, No. 3, pp. 34–35, March, 1992.     

甲醇在ZnI2催化下转化为triptane工艺的优化及催化剂再生研究：制备一种优质的航空汽油调和组分

采用间歇釜式反应器研究了甲醇在ZnI₂催化作用下转化为2,2,3-三甲基丁烷（triptane)的反应。优化了反应工艺条件并研究讨论了催化剂的失活机理及再生工艺。采用XRD,TG及XRF方法表征分析了催化剂反应前后,及催化剂再生后的物理化学性质。实验结果表明在反应温度为200^oC,初始压力0.35MPa,反应时间2h,甲醇:ZnI₂摩尔比为2:1的条件下,triptane的收率为12.2%。随着循环反应次数的增加,催化剂的催化活性降低,在失活的催化剂中有少量的I₂及ZnO形成。I元素的流失及ZnO的形成导致了催化剂活性的降低,采用HI再生催化剂并同时向原料中加入少量叔丁醇能恢复催化反应活性。叔丁醇是反应的引发剂,通过ZnI₂催化剂的重构及起始反应的引发而实现反应活性的恢复。
       

微波法制备AgCeY吸附剂及其脱硫性能的研究

采用微波辅助法成功制备了AgCeY吸附剂,采用XRD,BET,XPS和Py-FTIR等技术对吸附剂进行了表征,并对吸附剂的制备条件,平衡等温吸附,动力学和热力学进行了研究。研究表明：在微波辐射时间20 min,微波功率400 W,微波温度70 °C条件下制备的AgCeY吸附剂具有最佳的吸附脱硫性能。微波法制备的AgCeY吸附剂比传统的液相离子交换法制备的AgCeY具有更高的路易斯酸度,并且其脱硫能力有了显著提高。噻吩（TP）和苯并噻吩（BT）在AgCeY吸附剂上的吸附过程可用Langmuir模型来描述,动力学模型可用伪一级模、伪二级模型和Langmuir模型来描述。TP和BT在AgCeY吸附剂上的吸附过程是传质控制的,并且是一个自发放热过程。     

Fabrication of oxygen-defective tungsten oxide nanorods for deep oxidative desulfurization of fuel

Owing to the increasingly serious environmental issues caused by the sulfur burnt in fuel, desulfurization has become an important topic. In this work, an amphiphilic oxygen-defective tungsten oxide was synthesized by a colloidal chemistry method. The amphiphilic property and oxygen defects were well characterized, and the structure of the oxygen-defective tungsten oxide catalyst was investigated. In addition, the catalyst was employed in oxidative desulfurization system of fuel, and deep desulfurization was achieved. It was found that the very high oxidative desulfurization performance of oxygen-defective tungsten oxide catalyst resulted from both the amphiphilic property and oxygen defects. This work can provide a strategy for preparation of highly active metal oxide catalysts with oxygen defects in oxidative desulfurization reaction of fuel.     

吸附法燃油超深度脱硫的研究进展

传统的加氢脱硫工艺能耗高且难以超深度脱硫,而吸附脱硫成本相对较低,可超深度脱硫。综述了吸附法燃油超深度脱硫的研究进展。吸附脱硫技术分为物理吸附脱硫和反应吸附脱硫。物理吸附脱硫技术存在的关键问题是,燃油中相对大量的芳烃和烯烃等组分会与有机硫化物形成强烈的竞争吸附,导致吸附剂脱硫选择性及脱硫量较低;反应吸附脱硫技术由于在吸附剂表面将有机硫转化成了其他形式的更易吸附的硫化物,然后再吸附脱除,因而吸附脱硫选择性较高。目前,还原型反应吸附脱硫技术S-Zorb工艺已投产,而近年来发展迅速的氧化型反应吸附脱硫技术由于可在常温常压下进行,且不消耗氢气,极具应用前景。     

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%.     

Ultra-deep adsorptive desulfurization process over activated carbon and effects on quality of real diesel

Fuel cell applications require ultra-low-sulfur diesel (ULSD, total sulfur content ≤1?μg/g). With a breakthrough sulfur content of 1?μg/g, dynamic adsorptive desulfurization (ADS) and regeneration performance over activated carbon were investigated under ambient conditions for commercial diesel (total sulfur content of 34.83?μg/g). The quality of ULSD was in a rounded analysis. Results show that polyaromatic hydrocarbons (PAHs) have a negative impact on ultra-deep ADS. Cetane number, acidity, and content of PAHs in ULSD are superior to current standards of State V or Euro VI, which means that ultra-deep ADS has little effect on diesel quality.     

逆流旋转填料床中络合铁脱硫富液的再生研究

针对络合铁脱硫工艺中脱硫富液再生效率低、耗时长、设备大、降解严重等缺点,以逆流旋转填料床为再生设备,以脱硫富液再生为研究对象,考察了超重力因子、气体流量、液体流量、再生温度对再生率的影响;在相同操作条件下,与传统再生装置对比分析吸收-再生循环次数对脱硫液络合剂降解的影响。研究结果表明：脱硫富液的再生效率随超重力因子、气体流量的升高先增大后减小,随再生温度的升高而增大,随液体流量的增大而减小。在适宜的工艺参数下,逆流旋转填料床对脱硫富液的再生率可达到60%以上;在相同吸收-再生循环次数条件下与传统再生装置相比,逆流旋转填料床可有效缓解脱硫液络合剂的降解。因此,逆流旋转填料床再生技术具有传质效率高、再生耗时短、设备小、络合剂降解少等优点,应用前景广阔。     

炼厂燃料气的超重力吸收深度脱硫

针对炼厂加热炉用燃料气中低浓度硫化物,特别是有机硫化物,利用自主研发的深度脱硫吸收剂,考察并优化了超重力吸收脱硫工艺。结果表明:当模拟炼厂燃料气的进气总硫质量浓度为80～100 mg/m3时,在超重力机的床层填料为不锈钢波纹丝网,超重力因子为66,进气量为4 m3/h,液气比（吸收剂循环量与进气量的流量之比）为6 L/m3的最优超重力吸收深度脱硫工艺条件下,燃料气的总硫去除率高达96.4%。在3种进气总硫质量浓度为80～100,50～60,20～30 mg/m3情形下,模拟炼厂燃料气脱硫效果比较稳定,总硫去除率均大于90.1%,出气总硫质量浓度均小于4.62 mg/m3。     

混合氧化物载体对反应吸附剂Ni/ZnO的影响

The effect of mixed oxide support on the performance of the reactive adsorption desulfurization (RADS) for Ni/ZnO was invested by using thiophene in model gasoline in a fixed bed reactor. A series of oxide supports of Ni/ZnO was synthesized by co-precipitation method and characterized by XRD, N2-adsorption, TPR and NH3-TPD. It was found that the desulfurization capacity of Ni/ZnO is enhanced greatly when active components were supported on proper mixed oxide. Ni/ZnO supported on oxides exhibits much higher desulfurization efficiency and sulfur adsorption capacity than unsupported Ni/ZnO and the synthesized Ni/ZnO-SA adsorbent exhibits the highest efficiency for thiophene removal. The higher desulfurization activity and sulfur capacity of Ni/ZnO supported on SiO2-Al2O3 with small particle size, high specific surface area and large pore volume promotes the highly dispersion of active metal phase and the transfer of sulfur to ZnO with lower mass transfer resistance. γ-Al2O3 can weaken the interaction of active phases and SiO2 as well as increasing greatly the amount of weak acid. Therefore, these oxides have a great influence on the structure and chemical properties of the catalyst.     

燃料油中噻吩类硫化物脱除技术研究进展

综述了燃料油中噻吩类硫化物脱除技术的研究进展。认为加氢脱硫技术存在投资大,运行成本高等问题;吸附、氧化、生物等非加氢脱硫技术将成为未来发展的趋势。离子液体脱硫技术将成为噻吩类硫化物非加氢脱除技术的研究热点,工业化前景广阔。     

Ni/ZnO-Al_2O_3-SiO_2汽油脱硫吸附剂的再生

采用湿混法制备了Ni/Zn O-Al_2O_3-SiO_2汽油脱硫吸附剂,利用空气氧化燃烧法对失活吸附剂进行再生,考察了再生过程中再生条件对吸附剂再生性能的影响,并利用XRD、压汞、SEM、XPS等手段对新鲜吸附剂、失活吸附剂和再生吸附剂进行表征。表征结果显示,吸附剂失活的主要原因是ZnS和NiS_x的生成减少了活性中心的数量,并出现了一定程度的聚集,阻塞了吸附剂大孔道,使孔体积和孔径有所减小;再生吸附剂和新鲜吸附剂的晶体结构基本一样,但颗粒粒径有所增大,孔体积和比表面积减小。实验结果表明,在常压、温度480℃、再生气流量500 mL/min、再生气氧含量2%(φ)的再生条件下,再生后吸附剂的活性基本可以恢复至新鲜吸附剂水平。