超声波在柴油氧化脱硫中的应用

柴油氧化脱硫作为一种新的工艺,其深度脱硫技术已经受到了越来越多的关注,同时把超声波这种新兴技术应用于柴油脱硫中,大大减少了反应时间。着要介绍了超声波的产生、机理、作用及其在氧化脱硫过程中的强化原理。     

A Novel Technology for Desulfurization of FCC Diesel Fuels: Combination of Hydrogenation and Oxidation-assisted Ultrasound

Abstract

This new route that integrates with hydrodesulfurization (HDS) and ultra-sound-assisted oxidation desulfurization (UAODS) technology can be studied to decrease the sulfur content of high sulfuric FCC diesel fuel. In the integrating technology, the conventional HDS unit continues to produce below 500 μg/g hydrotreated diesel fuels, with UAODS unit used to make sulfur content below 50 μg/g, or even below 10 μg/g of diesel fuels. Since it has been discovered that cavitation can be originated from ultrasonic irradiation in water, ultrasound is an increasingly used tool to enhance chemical process rate. The addition of Fenton's reagent can enhance the sono-oxidative desulfurization efficiency for diesel fuels. UAODS has more advantages in removing thiophene and alkyl-thiophenes that are less reactive than other organosulfur species present in these hydrocarbon streams (e.g., alkyl sulfides, mercaptans) using HDS technology. The key to success is that the oxidative desulfurization process must be cost-effective versus the HDS revamp alternative available to refiners.     

超声波作用下柴油深度氧化脱硫的研究

催化氧化脱硫是降低柴油硫含量的非加氢脱硫工艺，在催化氧化溶剂抽提的基础上，引入超声波为反应提供能量，考察了超声频率、声强等因素对脱硫效果的影响。结果表明。以H2O2-有机酸为氧化剂，在室温，剂油比为0．05，搅拌速率为300r／min，反应时间为15min，频率为28kHz，声强为0．408W／cm^2的条件下进行柴油催化氧化反应，将得到的产品与萃取剂（DMF）在室温下按照1：1混合，萃取两次后进行分离，其脱硫率为94．8％，而未加超声波的脱硫率仅为67．2％，说明超声氧化脱硫效果明显优于未加超声波的氧化脱硫反应。     

柴油催化氧化脱硫催化剂的研究进展

综述了国内外柴油催化氧化脱硫技术中催化剂的研究进展,包括固体催化剂（杂多酸／杂多酸盐、有机酸盐、活性炭等）、液体催化剂（无机酸／有机酸、离子液体等）和气体催化剂（NOx）,指出了今后柴油催化氧化脱硫技术的研究方向,认为其将成为生产超低硫柴油的主要工艺之一。     

The Research of Ultra-deep Desulfurization in Diesel via Ultrasonic Irradiation Under the Catalytic System of H2O2-CH3COOH-FeSO4

Abstract

In recent years, many countries have drawn up strict laws regarding the sulfur-containing compounds of fossil fuels, especially the gasoline and diese. Ultra-deep desulfurization of fuel is a main component of fossil fuel development. The experiment imposes the photochemistry field on the catalytic oxidation system in order to broaden the newly desulfurization technology. The sulfur-containing compounds, such as dibenzothiophene (DBT) and its derivatives, in diesel fuel are oxidized to corresponding sulfones using H₂O₂-CH₃COOH-FeSO₄ oxidation systems via ultrasonic irradiation. Later, the oxidized sulfur compounds (sulfones) are extracted by a suitable polar solvent. The influences of the catalytic system, reaction time, and ultrasonic source (frequency, intensity) are tested on desulfurization efficiency. Experimental results show that the removal efficiency of the sulfur compound could amount to 97.5%, and the recovery of oil is above 92% under the catalytic system of H₂O₂-CH₃COOH-FeSO₄ by the assistance of ultrasound.     

催化裂化柴油空气氧化脱硫工艺研究

实验以空气作氧化剂,甲酸作催化剂,甲醇作萃取剂,以催化氧化反应与溶剂萃取相结合法,对催化裂化柴油进行氧化萃取脱硫。经单因素实验考察了催化剂用量、催化氧化温度、时间、空气压力及萃取剂的用量等对催化裂化柴油硫含量的影响。适宜的脱硫条件为:反应温度80℃,反应时间60 min,空气压力0.6 MPa,催化剂用量10%(与柴油的体积比)。经催化氧化,柴油硫含量可由1 694.2μg/g降至347.3μg/g,脱硫率达79.5%。     

Application of Microwave Technology for Desulfurization of Diesel Fuel

The microwave technology was introduced for the desulfurization of diesel fuel. The atmospheric second side-cut diesel fraction, which was supplied by Liaohe Petrochemical Company, was desulfurized by an oxidation process under microwave irradiation. Hydrogen peroxide (H202), can oxidize the sulfur compounds in diesel fuel selectively and convert them into sulfones. Based on the rule of dissolution by similar substances,these sulfones are removed from diesel fuel because they could be dissolved in solvent phase. So the sulfur content of diesel fuel is decreased. The influence of the concentration of oxidizing reagent, solvent phase to oil phase volume ratio (S/O), irradiation pressure, irradiation time, and the irradiation power have been investigated.The optimum conditions for the refining process was determined. The sulfur removal rate was 59.7% under the optimum conditions of 8%H2O2, S/O=0.25, 0.05MPa, 6 min, and 375W, respectively. When no microwave irradiation was applied, the removal rate was 11.5% only.     

直馏柴油络合萃取脱硫的实验研究

采用自制的脱硫络合萃取剂(TS-1),考察其对直馏柴油中硫化物的脱除效果。在萃取温度20℃、萃取时间5 min、相分离时间15 min、剂油体积比为2%的条件下,直馏柴油A的硫含量从711μg/g降到245μg/g,脱硫率为65.6%,柴油收率为99.6%,达到国Ⅲ车用柴油硫含量标准(350μg/g);继续增加剂油比到5%,柴油A的硫含量可降到42μg/g,脱硫率达94.1%,柴油收率为99.5%。在最佳操作条件下,对低硫柴油B(硫含量374μg/g)和高硫柴油C(硫含量1 737μg/g)进行络合萃取脱硫实验。结果表明,使用脱硫络合萃取剂TS-1后柴油B、柴油C都可达到较高的脱硫率。     

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。     

柴油深度脱硫中砜类氧化产物的萃取分离

 用极性有机溶剂萃取分离柴油催化氧化脱硫反应中的砜类氧化产物,筛选出萃取效果最好的萃取剂N,N-二甲基甲酰胺（DMF）,并采用功率超声萃取和恒温振荡萃取增强萃取脱硫效果。考察了萃取剂用量即剂/油体积比及两种操作状况下各主要工艺参数对萃取脱硫效果的影响,从而确定最佳操作条件。结果表明,当柴油/萃取剂(DMF)体积比为1,在功率超声萃取条件下(功率500W,频率59kHz,时间20min),柴油硫含量可从1703μg/g降至74.8μg/g;在恒温振荡萃取条件下(转速180r/min,温度40℃,时间40min),柴油硫含量可从1703μg/g降至116.0μg/g。     

FCC柴油氧化萃取深度脱硫工艺研究

以氧气作氧化剂、甲酸作催化剂、N-甲基吡咯烷酮作萃取剂,采用催化氧化反应与溶剂萃取相结合的方法对催化裂化柴油进行了氧化萃取脱硫实验。考察了催化剂用量、催化氧化温度、反应时间、氧气压力及萃取剂的用量等对催化裂化柴油脱硫率的影响。结果表明,在反应温度为80℃、反应时间为90min、充氧压力为0.6MPa、催化剂与油体积比为10%的条件下,柴油经催化氧化脱硫后,硫含量可从1694.2μg/g降到190.8μg/g,脱硫率达到88.7%;在萃取剂油体积比为1.0和室温条件下,用N-甲基吡咯烷酮萃取3次,再经硅胶吸附后柴油硫含量为37.5μg/g,柴油收率为94%,达到欧Ⅳ排放标准小于50μg/g的要求。     

降低减压渣油延迟焦化石油焦产品硫含量的研究

基于砜与亚砜的化学键键能低于噻吩化学键能，提出采用乙酸/双氧水氧化体系对减压渣油进行预氧化处理以降低延迟焦化石油焦产品的硫含量，同时考察了氧化减黏、水力空化强化氧化-减黏等工艺对延迟焦化石油焦硫含量的影响。结果表明，空化压力8 MPa，处理1次，并在410 ℃下减黏1 h时石油焦硫含量的降低效果最佳，硫质量分数由初始的4.12%降低至3.21%，同时产品分布数据表明，此条件下石油焦产率降低2.35百分点，液体收率提高1.93百分点。     

The Oxidative Desulfurization of HDS Diesel: Using Aldehyde and Molecular Oxygen in the Presence of Cobalt Catalysts

Abstract

Oxidative desulfurization of hydrodesulfurized diesel using aldehyde and molecular oxygen in the presence of cobalt catalysts was studied. Among the catalysts used, cobalt phthalocyaninetetrasulfonamide was found to be the most efficient catalyst for the oxidation of sulfur compounds present in diesel. The reactivity of 4,6-dimethyldibenzothiophene is greater compared to 4-methyldibenzothiophene. Sulfur content in diesel was reduced from 448 to 41 ppm by oxidation followed by extraction with acetonitrile. It was further reduced to 4 ppm by passing through a silica gel column.     

Oxidative Desulfurization of Diesel Fuel Using Ultrasound

Abstract

Catalytic oxizdation is a non-HDS technology to remove sulfur compounds from diesel fuel, and ultrasound irradiation was introduced to provide energy for this reaction. The effects of reaction temperature, time, and the ratio of oxidant and oil were investigated. The results show that under certain conditions, the optimal conditions were as follows: volume ratio of oxidant to oil was 1:10, reaction temperature was 50°C, and oxidation time was 10 min.     

柴油超深度加氢脱硫（RTS）技术研究

通过分析影响柴油超深度脱硫的主要因素,提出并开发了柴油超深度加氢脱硫（RTS）工艺, 进行了RTS技术生产超低硫柴油的工艺研究。结果表明,采用RTS技术,通过工艺流程和操作条件优化,对以高硫直馏柴油为主的原料,可在比常规加氢精制工艺高50%以上的空速下生产出硫含量小于50μg/g和10μg/g的超低硫柴油产品。RTS技术稳定性试验结果表明,RTS技术可以满足工业装置长周期运转的需要。     

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.     

用于FCC柴油氧化萃取脱硫的负载型磷钨酸催化剂和复合萃取剂

采用浸渍法制备磷钨酸(HPW)质量分数不同的半焦负载型催化剂HPW/Sc,利用扫描电镜、紫外漫反射吸收光谱和 N₂吸附-脱附分析方法表征了所制备 HPW/Sc 催化剂的结构,并在FCC 柴油的氧化萃取脱硫过程中将其作为氧化催化剂,考察了HPW 的负载量和萃取剂种类对氧化萃取脱硫率的影响。结果表明,半焦是 HPW 的良好载体,HPW 负载到半焦后保持了原有的Keggin 结构;在最优氧化反应和萃取条件下,FCC 柴油中的硫质量分数由1100 μg/g 降至89.1 μg/g, 脱硫率达到91.9%;评选出了柴油氧化萃取脱硫的专用复合萃取剂,用氢键理论和位阻效应解释了复合萃取剂可以提高回收率的原因。     

催化柴油氧化与萃取脱硫过程的数学模型研究

 通过催化柴油氧化及溶剂萃取脱硫实验，探索了柴油脱硫率变化规律及柴油中硫化物的氧化反应机制。基于硫化物顺序氧化反应机制和溶剂萃取原理，确定了柴油脱硫数学模型和硫化物氧化速率常数模型。利用脱硫实验数据进行模型参数估值，确定了硫化物氧化反应活化能及频率因子、溶剂萃取相平衡常数等模型参数。模型预测结果表明，柴油脱硫率随着柴油氧化时间的延长先提高然后降低，且脱硫率极大值随着氧化温度的降低而提高。在过氧化氢用量较少时，随着氧化溶液混合制备时间的延长，柴油脱硫率呈提高的趋势；而当过氧化氢用量较多时，柴油脱硫率呈先提高后降低的趋势。柴油脱硫率随着氧化溶液体积分数的增大先提高后趋于不变，随着萃取剂/油体积比的增大而提高。     

复合催化氧化直馏柴油脱硫的研究

在高压反应釜中,采用均相催化氧化脱硫催化剂和纯Oz对直馏柴油进行催化氧化脱硫,可达到很好的脱硫效果,但此法得到的氧化柴油酸值较大,加入助剂可以抑制烃类化合物的氧化,降低了氧化柴油的酸值,提高了氧化油收率,且硫含量也可达到欧洲Ⅱ类柴油标准(总硫<300μg/g)。结果表明,复合催化氧化脱硫使柴油中硫的质量分数降到271μg/g,酸值下降89.2%,氧化油收率提高1.4%。     

Span-60乳化剂用于流化催化裂化柴油氧化脱硫

以Span-60为乳化剂、双氧水为氧化剂、固载磷钨酸的半焦为催化剂,对流化催化裂化(FCC)柴油进行氧化脱硫;考察了反应时间、反应温度、Span-60乳化剂用量和双氧水用量对脱硫率的影响。实验结果表明,FCC柴油氧化脱硫的优化反应条件为:反应时间60m in、反应温度60℃、Span-60乳化剂用量(基于FCC柴油的质量分数)0.6%、双氧水用量(基于FCC柴油的质量分数)2%、催化剂用量(基于FCC柴油的质量分数)1.2%。在此条件下对FCC柴油进行氧化脱硫,FCC柴油中的硫含量由1 400μg/g降至84μg/g,脱硫率达94%。气相色谱分析结果显示,氧化脱硫后FCC柴油中的苯并噻吩衍生物、二苯并噻吩及其衍生物基本上被脱除。