Study on Separating Naphthenic Acids from Diesel Fuel by Microwave Irradiation

The microwave technology was introduced to separate naphthenic acids from diesel fuel. The decrease of zeta-potential of electric double layer on the W/O interface and the reduction of diesel fuel viscosity were responsible for the accelerated separation of naphthenic acids under microwave irradiation. The influences of dosage of alkali compound solvent (Mp / MT), irradiation pressure, irradiation time, irradiation power, the settling time and oil phase-to-solvent phase volume ratio (O/S) had been investigated. The optimum process conditions for the refining process were determined. The removal of naphthenic acids reached 98.4% when the optimum conditions were proposed as follows: Mp/MT=1 .5,0.05MPa, 6 min, 375W, 25min and O/S=10, respectively. The diesel recovery could reach 99.3% and the quality of the treated diesel oil was good enough to meet the specification of GB252-2000.     

外加磁场对催化裂化柴油氧化脱硫作用的研究

以石油醚为溶剂,二苯并噻吩为模型硫化物,配制成模拟油,在螺线管磁场中对油品进行氧化脱硫实验。结果表明,在外加磁场作用下,以30%过氧化氢为氧化剂,当电流强度为11 A、剂油比3.0、反应温度0 ℃、反应时间60 min时,模拟油中的硫含量可以从1 000μg/g降至118 μg/g。对于硫含量为5 647μg/g的催化裂化柴油（25 mL）,在氧化剂过氧化氢（30%）用量5 mL、反应时间60 min、反应温度0 ℃、螺线管电流强度为11 A的条件下,催化裂化柴油的平均脱硫率为70.3%;而无磁场时催化裂化柴油的平均脱硫率为67.2%。     

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。     

相转移催化氧化-萃取脱除直馏柴油中硫化物的研究

以四丁基溴化铵(TBAB)为相转移剂，采用H2O2-HCOOH催化氧化直馏柴油中含硫化合物，利用N, N-二甲基甲酰胺(DMF)萃取脱除氧化含硫化合物。通过考察TBAB用量、反应温度、反应时间、H2O2和HCOOH用量、剂油比、搅拌速率对柴油脱硫效果的影响，确定适宜的操作条件为：TBAB用量0.10%，反应温度60 ℃，反应时间2.0 h，V(H2O2)/V(柴油)为10%，V(H2O2)/V(HCOOH)=1:2，剂油体积比2∶5，搅拌速率150 r/min。在该反应条件下，直馏柴油的脱硫率达到82.03%，柴油收率为92.02%。模拟柴油脱硫反应动力学结果表明，H2O2-HCOOH相转移催化氧化脱除噻吩硫反应为表观一级反应，活化能为7.47 kJ/mol。     

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。     

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%.     

Removing Naphthenic Acids from Diesel Oil by Microwave Irradiation

Microwave technology is introduced for removal of naphthenic acid from diesel oil. The decrease of Zeta-potential of interface and the viscosity of diesel oil are responsible for the acceleration of separation of naphthenic acid with microwave irradiation. It was observed that the separation percentage changed with the dosage of alkali compound solvent, irradiation pressure, irradiation time, irradiation power, settling time, and oil phase-to-solvent phase volume ratio (O/S). The removal rate of naphthenic acid was maximum when the optimum conditions were suggested to be M_p/M_T = 1.5, 0.05 MPa, 6 min, 375 W, 25 min, and O/S = 10, respectively.     

Diesel desulfurization using a ultrasound-assisted oxidative process

In this study, the removal of sulfur compounds from diesel samples using ultrasound-assisted oxidative desulfurization (UAODS) process in presence of different types of oxidizing agents was studied. Experiments were performed to assess the effects of influential parameters on the performance of UAODS process including ultrasonic irradiation time, oxidant type, mass ratio of oxidant to diesel fuel (oxidant: diesel), and finally acetic acid as an oxidative promoter. The efficiency of sulfur compounds removal from the diesel fuel dramatically improved using appropriate oxidative process with the assistance of ultrasound irradiation. H₂O₂ was found to be the most promising oxidant component whose concentration in the media directly affected total sulfur removal and thiol group conversion efficiencies. Using 4 wt% of H₂O₂ followed by 15 min of ultrasonic irradiation leaded to sulfur removal efficiency of 76% and thiol group conversion of 79% at ambient temperature and atmospheric pressure. Using acid acetic as the promoter of H₂O₂ also leaded to further sulfur compounds removal.     

BrØnsted酸性离子液体在萃取氧化二苯并噻吩中的应用

 以具有BrØnsted酸性的吡咯烷酮离子液体N-甲基-2-吡咯烷酮氟硼酸盐([Hnmp]BF₄)为萃取剂和催化剂, 含30%质量分数H₂O₂的双氧水为氧化剂, 二苯并噻吩(DBT)的正辛烷溶液作为模型油, 同时进行萃取脱硫和氧化脱硫, 考察了n(H₂O₂)/n(S)、DBT初始浓度和反应温度对脱硫率的影响. 结果表明, [Hnmp]BF₄-H₂O₂体系产生的羟基自由基能将DBT氧化成相应的砜而进入离子液体相, 从而脱除了模型油中的S; 当n(H₂O₂)/n(S)=3、反应温度为60℃、模型油与离子液体等体积时, 在60min内可将油相中的S质量浓度为1550μg/ml 的DBT完全氧化脱除; DBT初始浓度越高, S的完全脱除就越困难. 离子液体重复再生使用7次后, 脱硫率明显降低.     

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。     

微波辐射柴油脱酸精制

介绍了一种新的柴油脱酸精制方法——微波辐射法。考察了精制过程中的最佳实验条件。在V(Diesel)=0．25、反应体系压力0．05MPa、恒压辐射时间5mm、微波辐射功率375W、静置时间25min的条件下，可将柴油的酸度由90．7mgKOH／100m1降至3．99mgKOH／100ml，达到国家标准GB252-93的优质柴油质量要求(酸度小于5mgKOH／100m1)。该精制过程对柴油性能无影响，回收率达到99．7％；同时副产环烷酸，其粗酸值为182．5mgKOH/g。中性油含量为34．2％。该精制过程省时、耗电量小，预期对环境友好。     

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.     

Diesel desulfurization using a UV-photocatalytic process

In this paper, the use of ultraviolet irradiation using TiO₂ as a photocatalyst for diesel desulfurization was studied in a batch reactor. The effects of operational parameters such as operation time, the presence of oxidant, oxidant type, and irradiation power on the performance of the desulfurization process were investigated. The results revealed that total sulfur and thiol group removals from diesel samples were about 61.91% and 58.64%, respectively, at the power of 18 W of UV irradiation and 2 wt% H₂O₂ as an oxidizing agent using 40 min of irradiation as an optimum time required. It was also found that hydrogen peroxide is the most promising oxidant for the desulfurization of diesel fuel. By increasing the power of ultraviolet irradiation from 18 W to 30 W, total sulfur removal and thiol group conversion were increased to 90% and 88%, respectively. However, total sulfur removal and thiol group conversion at 30 W ultraviolet irradiation with 2 wt% TiO₂ and without using any oxidants were about zero and 14%, respectively.     

Removing Naphthenic Acids from Diesel Oil by Microwave Irradiation

Abstract

Microwave technology is introduced for removal of naphthenic acid from diesel oil. The decrease of Zeta-potential of interface and the viscosity of diesel oil are responsible for the acceleration of separation of naphthenic acid with microwave irradiation. It was observed that the separation percentage changed with the dosage of alkali compound solvent, irradiation pressure, irradiation time, irradiation power, settling time, and oil phase-to-solvent phase volume ratio (O/S). The removal rate of naphthenic acid was maximum when the optimum conditions were suggested to be M _p /M _T = 1.5, 0.05 MPa, 6 min, 375 W, 25 min, and O/S = 10, respectively.     

减二线馏分油微波辐射脱酸新方法的研究

以NaOH与去离子水为复合溶剂用微波辐射法对江苏减二线馏分油进行了脱酸精制研究。得到的最佳精制条件为 :V(复合溶剂 )∶V(油 ) =0 .2 2∶1、压力 0 .0 9MPa、恒压辐射时间 4min、微波功率 375W、静置时间 2 5min。馏分油的酸值 (KOH)由 0 .5 7mg/ g降至 0 .0 4 81mg/ g ,馏分油回收率为 99.3%。     

油溶性过氧化环己酮在FCC柴油氧化脱硫中的应用研究

制备了油溶性过氧化环己酮,将其作为柴油脱硫氧化剂应用于FCC柴油的氧化-萃取脱硫中,实验考察了反应温度、反应时间、剂油比等反应条件对脱硫率的影响,结果表明,在反应温度为100 ℃、氧化剂与柴油的体积比为2：50、反应时间3.0 h、萃取剂与柴油的体积比为5：10的条件下,可脱除FCC柴油中93.0 %的硫化物,柴油回收率达99 %;该柴油经二次萃取后,硫含量降至33.9μg/g,可满足欧IV排放标准的要求。     

RS-1000（S）器外预硫化催化剂在加氢装置上的应用

介绍了RS-1000（S）器外预硫化催化剂在中国石油克拉玛依石化公司汽柴油加氢装置上的工业应用。工业标定结果表明,在2.5h-1的较高空速下,采用加氢精制工艺在RS-1000(S)催化剂的作用下生产的精制柴油其平均脱硫率为91.21%,脱氮率为59.76%,产品质量达到了GB/T1947-2003轻柴油质量标准,同时符合世界燃油规范（Ⅱ类）和欧盟（Ⅲ类EN590-99）的轻柴油质量要求。 RS-1000（S）催化剂活化过程历时13 h,与器内湿法硫化相比可节省近两天的时间。此外,还可以简化开工步骤,不需要处理难闻且有毒害的硫化剂。     

Oxidation of Dibenzothiophene and Desulphurization of Diesel

In order to meet the future regulations, sulfur compounds have to be removed completely from fuels. A study was carried out on the process development for selective oxidation of DBT using a series of simple acid catalyst systems with hydrogen peroxide as oxidant. The sulfoxides and sulfones formed were extracted by adsorption over a silica gel column. The oxidation reactivity and mechanism were studied and explained. The optimized experimental conditions were extended to diesel for the oxidation of dibenzothiophene, 4-methyl dibenzothiophene, and 4,6-dimethyl dibenzothiophene. The sulfur reduction in diesel fuel to the desired level could be achieved using the simple mixed acid catalyst.     

FHUDS-6催化剂在4.1Mt／a柴油加氢装置上的工业应用

介绍柴油超深度加氢脱硫催化剂 FHUDS-6 在国内某大型炼油厂4.1Mt／a柴油加氢装置上的首次工业应用情况,并对使用该催化剂的满负荷标定数据进行分析。结果表明,在催化裂化柴油比例高达11%、床层平均反应温度 352 ℃、空速 2.53 h-1、氢分压 6.15 MPa、氢油体积比 254.3 的工况下,FHUDS-6 催化剂具有较高的脱硫、改质活性,十六烷值提高幅度达 5.7 个单位,脱硫率达 98.02%,精制柴油产品质量可以满足国Ⅲ柴油排放标准要求。     

Removal of Sulfur from Hydrotreated Diesel Fuel

A simple and ecological two-stage method of removing sulfur from hydrotreated diesel fuel is described. In the first stage, the sulfur compounds left in the fuel are oxidized by hydrogen peroxide into sulfones, and in the second stage, the sulfones formed are extracted from the oxidation product by adsorption with silica gel. The diesel fuel obtained with this method satisfies the new European standards for sulfur content.__________Translated from Khimiya i Tekhnologiya Topliv i Masel, No. 3, pp. 42 – 44, May – June, 2005.