【作者】 于凤丽；

【导师】 王睿；

【作者基本信息】 山东大学 ， 环境工程， 2013， 博士

【摘要】 燃油燃烧过程中释放的硫氧化物(SOx)属于危害极大又较难治理的大气污染物之一,可以诱发酸雨、气溶胶等污染的形成,还严重危害人体健康。鉴于燃油含硫的危害,世界各国和地区相继颁布了严格的燃油含硫标准。研究人员将超低硫燃油生产技术作为主要研究方向。氧化脱硫(oxidative desulfuri-zation, ODS)技术,具有反应条件温和、脱硫率高、工艺简单、易操作、设备投资少、运行费用低、低碳节能环保等诸多优点,已经成为超低硫燃油技术开发的一个热点。杂多化合物因具有反应条件温和、高活性、高稳定性、高选择性等优点,作为环境友好型催化剂被广泛应用于氧化脱硫领域研究。文本以杂多酸阴离子为主体、改变客体组成,制备了四类基于杂多酸阴离子催化功能的不同主客体型催化剂(包括：杂多酸铯盐负载型催化剂、杂多酸柱撑类水滑石催化剂、有机-无机型杂多酸类催化剂和氨基改性MCM-41固载杂多酸催化剂),并考察了四类杂多酸型催化剂对模拟油品的催化氧化性能。本文合成了杂多酸铯盐负载型催化剂,其既保留了主体杂多酸的催化性能又通过客体材料实现了杂多酸固化,反应结束后催化剂可过滤回收且再生操作简单,且催化氧化脱硫性能良好。本文首先通过共沉淀法合成了三种杂多酸铯盐(Cs2.5H0.5PW12O40、CS2.5H0.5PMo12O40和Cs2.5H1.5SiW12O40),比较了它们对模拟油品氧化脱硫的催化性能(二苯并噻吩DBT溶于正辛烷,制备硫含量500ppmw质量比的模拟油品)。结果发现,Cs2.5H0.5PW12O40的催化性能最佳。以Cs2.5H0.5PW12O40为催化剂,过氧化氢为氧化剂,乙腈为萃取剂,研究了反应温度、催化剂用量、氧化剂用量和催化剂与氧化剂预接触时间等因素的影响,得到了优化的氧化脱硫条件。其次,将Cs2.5H0.5PW12O40分别负载于碳纳米管(CNT)、活性炭(AC)和层析硅胶(SiO2),制备了碳纳米管负载磷钨酸铯盐(CsPW/CNT).活性炭负载磷钨酸铯盐(CsPW/AC)和层析硅胶负载磷钨酸铯盐(CsPW/SiO2),并考察了当负载量相同时三种催化剂催化氧化脱硫的性能。结果表明,CsPW/CNT催化性能最佳。比较了不同负载量的CsPW/CNT的催化活性,结果表明,当负载量为30%(质量比)时CsPW/CNT(记作30%CsPW/CNT)的催化活性最佳。选取30%CsPW/CNT为催化剂,过氧化氢为氧化剂,乙腈为萃取剂,研究了反应温度、催化剂用量、氧化剂用量和催化剂与氧化剂预接触时间等因素的影响,得到了优化的氧化脱硫条件。在最佳实验条件：催化剂用量为正辛烷质量1%,O/S摩尔比20,催化剂与H2O2预接触时间20min,反应温度60℃,正辛烷体积用量60mL,乙腈用量(V乙腈：V油=1),以30%CsPW/CNT为催化剂,考察了对不同噻吩类含硫化物的催化活性。结果表明,由于噻吩类含硫化物本身硫原子电子云密度和空间位阻效应的双重作用,其脱硫难易顺序为：DBT>4,6-二甲基二苯并噻吩(4.6-DMDBT)>苯并噻吩(BT)>噻吩(TH)。通过过滤回收焙烧再生,五次回收利用后的30%CsPW/CNT催化活性略有下降,说明载体本身稳定性较好,该催化剂具有可循环再生实用性。最后,在最佳实验条件下考察了30%CsPW/CNT催化柴油氧化脱硫效果。结果表明,柴油含硫量由507ppmw降至48.1ppmw,硫化物去除率达97.1%,柴油回收率达97.1%。本文通过离子交换法,将杂多阴离子插入类水滑石层间,使其与层板间金属离子以化学键形式连接,既保留了主体杂多酸阴离子的催化性能,又保留了客体类水滑石不溶于水不溶于油的特性,反应结束后催化剂沉淀易于回收。研究了采用不同杂多酸阴离子柱撑二元或三元类水滑石材料作催化剂,对模拟油品中DBT氧化脱硫催化活性变化规律的影响。首先,对于主体杂多酸阴离子不同、客体二元(或三元)类水滑石相同的杂多酸柱撑类水滑石,研究发现其催化氧化脱硫活性与插层固载的杂多酸阴离子种类和数量有关,其催化活性递减次序为：磷钼酸系列柱撑类水滑石>磷钨酸系列柱撑类水滑石>硅钨酸系列柱撑类水滑石。其次,对于主体杂多酸阴离子相同、客体二元(或三元)类水滑石不同的杂多酸柱撑类水滑石,其催化氧化脱硫活性和类水滑石中金属离子半径比近似原则有关。当类水滑石中二价、三价金属离子半径比越接近1,其合成类水滑石的层板结构越接近八面体配位的典型结构,越容易向其层间插入阴离子。结果表明,主体杂多酸阴离子相同、客体二元类水滑石不同的杂多酸柱撑类水滑石催化剂活性递减顺序为：NiAl-LDHs系列>MgAl-LDHs系列>Zn-Al-LDHs系列。主体杂多酸阴离子相同、客体三元类水滑石不同的杂多酸柱撑类水滑石催化剂活性递减顺序为：NiMgAl-LDHs系列>NiZnAl-LDHs系列>MgZnAl-LDHs系列。分别利用NiAl-PMo和NiMgAl-PMo为催化剂,过氧化氢为氧化剂,乙腈为萃取剂,研究了催化剂用量、反应温度、氧化剂用量、催化剂与氧化剂预接触时间等因素的影响,得到了优化的脱硫验条件,且NiAl-PMo的催化活性优于NiMgAl-PMo。在最佳实验条件下,噻吩类含硫化合物被氧化难易程度也受其本身硫原子电子云密度和空间位阻效应双重作用影响,其难易顺序为：DBT>4,6-DMDBT>BT>TH。另外,NiAl-PMo在噻吩类含硫化合物的催化氧化中展现了优异的催化活性和重复利用性能,经五次循环使用后,基本没有活性损失。在最佳实验条件：催化剂用量为柴油质量1%,氧化剂用量满足O/S摩尔比15,催化剂与H202预接触时间5min,反应温度60℃,乙腈用量(V乙腈：V柴油=1),以NiAl-PMo为催化剂,对柴油进行了氧化脱硫实验研究。结果表明,柴油中硫含量从492ppmw降至44.3ppmw,脱除率达90.4%,回收率96.8%。本文制备了一种反应控制的相转移催化剂,即有机-无机型杂多酸,其在氧化脱硫反应过程中呈现“固-液-固”态变化,且其相态变化受过氧化剂控制,整个氧化脱硫反应体系属于反应控制相转移催化体系。本文合成了四种有机-无机型杂多酸,包括：[π-C5H5NC16H33]3[PW4O16]、[π-C5H5NC16H33]3[PMo4O16]、[π-C5H4NC12H25]3[PW4O16]和[π-C5H5NC12H25]3[PMo4016]。考察了这四种有机-无机型杂多酸在氧化脱硫体系中的催化性能,结果表明,[π-C5H5N16H33]3[PW4O16]催化性能最好。以[π-C5H5NC16H33]3[PW4016]为催化剂,过氧化氢为氧化剂,乙腈为萃取剂,研究了改变催化剂用量、反应温度、氧化剂用量、催化剂与氧化剂预接触时间等实验条件对脱硫效果的影响,确定最佳实验条件。研究发现,在常温常压条件下,有机-无机型杂多酸以固体形式存在,具有亲水亲油性,但不溶于油水两相反应；当催化剂与H202发生接触反应时,生成具有水溶性的过氧酸活性物质,溶于乙腈相中与含硫化合物发生氧化反应；当[π-C5H5NC16H33]3[PW4016]与H2O2发生接触反应时,生成具有水溶性的过氧酸活性物质,同时其分子内有机基团具有亲油性的特性,加速发生氧化反应。反应结束后,因H202消耗殆尽,催化剂失去活性,转化成为在油水两相中均不溶解的有机-无机型杂多酸,从油水两相中分离出来,最终以沉淀的形式析出。整个过程表明催化剂发挥作用时具有均相催化的特征,当反应结束后,催化剂发生相的变化而从反应体系中析出,实现了催化剂的自动分离与简易回收。在最佳实验条件下,[π-C5H5NC16H33]3[PW4O16]经过三次循环使用,对模拟油品中DBT的脱除率可达98%,说明其仍具有较好的催化活性。将其应用于柴油脱硫,在最佳实验条件：催化剂用量为正辛烷质量的1%、反应温度为60℃、氧化剂用量满足氧硫摩尔比10、催化剂与氧化剂预接触时间10min,柴油含硫量由515ppmw降至44.8ppmw,去除率达91.3%,回收率达95.9%。本文将氨基作引入基团使杂多酸被锚定于MCM-41分子筛孔道内制备了氨基改性MCM41型杂多酸,其利用MCM-41的多孔结构即保持了杂多酸的催化剂性能又增加了其比表面积,避免了传统负载型MCM41杂多酸催化剂在使用过程中的流失,通过过滤即可实现催化剂回收。首次将EDTA-2Na作为H2O2分解反应抑制剂引入氧化脱硫体系研究,并考察了其加入对DBT脱除效果的影响。将不同杂多酸锚定于氨基改性MCM-41分子筛孔道内部,合成了包括：磷钨酸、磷钼酸、磷钼一钒酸、磷钼二钒酸、磷钼三钒酸分别固载于氨基改性MCM-41分子筛(分别记作：MCM41-NH-PW、MCM41-NH-PMo、MCM41-NH-V1、MCM41-NH-V2和MCM41-NH-V3)。 FT-IR谱图、SEM和XRD分析结果表明,合成的氨基改性MCM-41型杂多酸保持了Keggin型结构,且具有MCM-41分子筛的介孔结构特征。考察了上述五种催化剂的氧化脱硫性能,结果表明MCM41-NH-PW催化活性最大。以MCM41-NH-PW为催化剂,研究了催化剂用量、反应温度、氧化剂用量、催化剂与氧化剂预接触时间等对模拟油品氧化脱硫的影响,并确定最佳反应条件。由于硫原子电子云密度和空间位阻的双重作用,MCM41-NH-PW对不同含硫化合物氧化脱硫催化活性递减次序为：DBT》4,6-DMDBT>BT>TH。在最优实验条件：催化剂用量为柴油质量1%；O/S摩尔比15；催化剂与H202预接触时间10min；反应温度60℃；乙腈用量(V乙腈：V油=1),以MCM41-NH-PW为催化剂,H202为氧化剂,乙腈为萃取剂,考察了EDTA-2Na的加入对模拟油品中DBT脱除效果的影响。结果表明,当10mL浓度0.02mol/L的EDTA-2Na加入上述反应体系,反应180min后,DBT脱除率明显提高,由96.8%增至100%。主要原因是：由于EDTA-2Na与溶液中痕量金属离子结合形成稳定的环状金属螯合物,可以有效抑制痕量金属离子对过氧化氢的催化分解作用,从而提高过氧化氢利用率。利用回收的MCM41-NH-PW为催化剂,第1、2次重复利用实验中DBT脱除率明显下降,之后的重复利用实验中,DBT脱除率下降不明显。这主要是由于在催化剂制备过程中,有少量磷钨酸吸附在MCM-41表面。当MCM41-NH-PW重复使用时,这部分磷钨酸逐渐从MCM-41表面脱落,致使单位质量MCM41-NH-PW所含磷钨酸阴离子比例降低,最终影响催化效果。在最佳实验条件：催化剂用量为柴油质量比1%,0/S摩尔比15,催化剂与H202预接触时间5min,反应温度60℃,乙腈用量(V乙腈：V柴油=1),抑制剂EDTA-2Na(浓度0.02mol/L)10mL,以MCM41-NH-PW为催化剂,考察了其催化柴油氧化脱硫效果。柴油含硫量由496ppmw降至49.2ppmw,硫化物去除率达90.1%,柴油回收率达96.2%。文中通过研究DBT氧化反应动力学,确定对于不同杂多酸阴离子功能化主客体型催化剂,DBT的表观反应级数均为一级,DBT的表观活化能在45.2-49.4kJ/mol之间。通过红外谱图发现杂多酸阴离子首先被H202氧化成过氧杂多酸阴离子,通过过氧杂多酸阴离子使硫化物中硫原子被氧化,硫化物被氧化活性大小受硫原子电子云密度和硫原子附近空间位阻效应双重影响。研究还发现,DBT砜是DBT的唯一氧化产物,且全部留存于乙腈相中,实现了氧化脱除油品中含硫化合物的目的。更多还原

【Abstract】 A great deal of sulfur oxide has been emitted from fuel oil combustion, and has been found to contribute to acid rain and aerosol, even to endanger people’s health. Due to the danger of sulfur compounds in fuel oil, the limitation of S content in fuel oil becomes more critical in the world. The aim of researchers is to find out the production technology of ultra-low sulfur fuel oil. Oxidative desulfurization (ODS) is considered to be one of the most promising desulfurization methods for its mild reaction condition, high efficiency, simple technology, low cost, low carbon and environment-friendly. Heteropoly compounds have the advantage of mild reaction conditions, high catalysis, high stability and high selectivity. Heteropoly compounds, as a new environment-friendly catalyst for ODS, have attracted the attention of worldwide researchers during the past years.In this paper, four heteropoly compounds with the heteropolyacid anion as subject and the change of object were prepared as catalyst, including supported for heteropolyacid cesium, heteropolyacids pillared hydrotalcite like compounds, organic-inorganic heteropolyacids, and immobilization of heteropolyacids on amino group functionalized MCM-41moleculars sieves. And we studied the catalysis of four catalysts in the ODS process.Supported for heteropolyacids cesium was synthesized, which keeps the catalytic performance by the subject of heteropolyacid and was achieved fixation by the object. The catalyst can be recovered by filtration after reaction. The operation of catalyst regeneration is simple. And it shows excellent catalytic performance on ODS. Three heteropolyacids cesium were prepared by coprecipitation, including CS2.5H0.5PW12O40, Cs2.5H0.5PMo12O40and Cs2.5H1.5SiW12O40. Compared the catalysis of them on ODS in simulated fuel oil, Cs2.5H0.5PW12O40showed the best catalytic performance. The catalysis of Cs2.5H0.5PW12O40in an ODS process was studied with H2O2as oxidant and acetonitrile as extractant. The main factors affecting the desulfurization process were investigated, including temperature, the amount of catalyst and oxidizing agent, and the pre-reaction time, obtaining finally the optimum experimental conditions. Then, Cs2.5H0.5PW12O40was supported to CNT, AC and silica column respectively to prepared CsPW/CNT, CsPW/AC and CsPW/SiO2.Compared the catalysis of them on ODS in simulated fuel oil by the same loading level. Experiment results show the catalysis of CsPW/CNT is the best. Compared the different loading level of CsPW/CNT, it shows the catalysis of30%loading level of CsPW/CNT is the best. With30%CsPW/CNT as catalyst, H2O2as oxidant and acetonitrile as extractant, the main factors affecting the desulfurization process were investigated, including temperature, the amount of catalyst and oxidizing agent, and the pre-reaction time, obtaining finally the optimum experimental conditions. Under the optimal conditions(catalyst dosage,1%the mass of normal octane; O/S molar ratio,20; pre-reaction time,20min; temperature,60℃; acetonitrile dosage,100%the volume of normal octane), compared the desulfurization efficiency of different sulfur compounds with the catalyst of30%CsPW/CNT on the same S-content simulated fuel oil. It shows that the oxidation reactivity of different sulfur compounds was in the order of DBT>4.6-DMDBT> BT> TH. The result shows the electron density of sulfur compounds on the sulfur atoms and the space steric hindrance were two important factors in the ODS. By filtration, recycling and roasting regeneration, the catalysis of the fifth recycling30%CsPW/CNT was down slightly. It shows the supporter was high stability. And the catalyst can be reused. Under the optimal conditions, the desulfurization efficiency of diesel was investigated. It shows that S-content in diesel decreased from507ppmw to48.1ppmw, the desulfurization efficiency90.5%and the recovery rate97.1%.Heteropolyacids pillared hydrotalcite like compounds were prepared by ion exchange. Heteropolyacid anions insert hydrotalcite like compounds, the chemical attachment between the heteropolyacid anions and the interlaminar metal ions, which keeps the catalytic performance by the subject of heteropolyacid and achieves the characteristic of insoluble in water or fuel oil the object of hydrotalcite like compounds oxidative desulfurization. The catalyst can be recovered by filtration after reaction. The catalysis in an ODS process of DBT in simulated fuel oil was studied, which were prepared by the different heteropolyacids anion pillared bimetal (or trimetal) hydrotalcite like compounds. At first, when the catalyst were prepared by the different subject of heteropolyacids anion and the same object of bimetal (or trimetal) hydrotalcite like compounds, the catalytic activity of them was related to the kind and amount of heteropolyacids. Their catalytic activity decreased according to the order: phosphomolybdic acid pillared hydrotalcite like compounds> phosphotungstic acid pillared hydrotalcite like compounds> silicotungstic acid pillared hydrotalcite like compounds. Secondly, when the catalyst were prepared by the same subject of heteropolyacids anion and the different object of bimetal (or trimetal) hydrotalcite like compounds, the catalytic activity of them was related to the ionic radius comparison similar principles. When the rate of divalent metal ionic radius and trivalent metal ionic radius is near one in hydrotalcite like compounds, its layer board structure is close to the typical structure of octahedral coordination. It shows that when the same subject of heteropolyacids anion and the different object of bimetal hydrotalcite like compounds in the catalysts, their catalytic activity decreased according to the order: NiAl hydrotalcite like compounds> MgAl hydrotalcite like compounds> ZnAl hydrotalcite like compounds. When the same subject of heteropolyacids anion and the different object of trimetal hydrotalcite like compounds in the catalysts, their catalytic activity decreased according to the order:NiMgAl hydrotalcite like compounds> NiMgAl hydrotalcite like compounds> MgZnAl hydrotalcite like compounds. With NiAl-PMo or NiMgAl-PMo as catalyst, H2O2as oxidant and acetonitrile as extractant, the main factors affecting the desulfurization process were investigated, including temperature, the amount of catalyst and oxidizing agent, and the pre-reaction time, obtaining finally the optimum experimental conditions. And the catalysis activity of NiAl-PMo is better than NiMgAL-PMo. Under the optimum experimental conditions, we compared the desulfurization efficiency of different sulfur compounds with the catalyst of NiAl-PMo on the same S-content simulated fuel oil. It shows that the oxidation reactivity of different sulfur compounds was in the order of DBT> 4.6-DMDBT> BT> TH. The result shows the electron density of sulfur compounds on the sulfur atoms and the space steric hindrance were two important factors in the ODS. The catalysis of the fifth recycling NiAl-PMo was never down. It exhibits excellent catalyzed active properties and utilization. Under the optimal conditions(catalyst dosage,1%the mass of normal octane; O/S molar ratio,15; pre-reaction time,5min; temperature,60℃; acetonitrile dosage,100%the volume of diesel), we investigated the desulfurization efficiency of diesel. It shows that S-content in diesel was decreased from492ppmw to44.3ppmw, the desulfurization efficiency90.4%and the recovery rate96.8%.In this paper, organic-inorganic heteropolyacids were prepared, including [π-C5H5NC16H33]3[PW4O16],[π-C5H5NC16H33]3[PMO4O16],[π-C5H5NC12H25]3[PW4O16] and [π-C5H5NC12H25]3[PMo4O16].During the reaction process, the phase state of catalyst changed in "solid-liquid-solid". The results show that organic-inorganic heteropolyacids are phase transfer catalyst and oxidative desulfurization system belongs to the phase transfer catalysis system controlled by reaction. The efficiency of oxidative desulfurization was investigated on the four kinds of catalysts under same conditions using the simulated oil prepared by dissolving organo-sulfur in normal octane. The results show that the catalytic activity of [π-C5H5NC16H33]3[PW4O16] is the best. With [π-C5H5NC16H33]3[PW4O16]as catalyst, H2O2as oxidant and acetonitrile as extractant, the main factors affecting the desulfurization process were investigated, including temperature, the amount of catalyst and oxidizing agent, and the pre-reaction time, obtaining finally the optimum experimental conditions. It shows that the phase state of organic-inorganic heteropolyacids is solid under normal pressure and temperature and it is insoluble in water or oil. When it reacted with H2O2, the production of peroxide heteropolyacid is soluble in acetonitrile and it react with sulfur compounds. When [π-C5HsNC16H33]3[PW4O16] reacted with H2O2, the organic part of the production of peroxide heteropolyacid is lipophilicity, which can promoted the oxidative reaction. The catalyst [π-C5H5NC16H33]3[PW4O16] can be reclaimed by auto precipitation due to the exhausting of H2O2.It shows that the catalyst has the characteristics of homogeneous catalysis, the phase state of which changes in the precipitation from the reaction system after the reaction. It realized the automatic separation and recycling of the catalyst. On the similar conditions, the catalyst of the3th recovered [π-C5H5N C16H33]3[PW4O16], the DBT conversion was nearly98%after120min, which was quite close to the result of fresh catalyst. The catalytic activity of the recycled [π-C5H5NC16H33]3[PW4O16] is almost the same as the fresh. We investigated the desulfurization efficiency of diesel with [π-C5H5NC16H33]3[PW4O16] as catalyst. It shows that S-content in diesel was decreased from515ppmw to44.8ppmw, the desulfurization efficiency91.3%and the recovery rate96.2%.The heteropolyacids have been immobilized on the inner surface of amino group functionalized MCM-41moleculars sieves. A new kind of catalyst were prepared, which keeps the catalytic performance mesoporous and avoids the loss of heteropolyacids in the traditional MCM-41supported heteropolyacids. And it can be recycled by filtration. EDTA-2Na was involved in the ODS as H2O2decomposition reaction inhibitors for the first time. The catalysts were prepared on the different heteropolyacids immobilization on amino group functionalized MCM-41moleculars sieves, including MCM41-NH-PW, MCM41-NH-PMo, MCM41-NH-V1, MCM41-NH-V2and MCM41-NH-V3. The five catalysts were synthesized and characterized by FT-IR, X-ray diffraction and SEM. The results show that they have the Keggin-type heteropolyacids and the structure of mesoporous. Compared with the above catalysts, the desulfurization efficiency of DBT in simulated fuel oil was investigated.It showed that the catalysis activity of MCM41-NH-PW was the best. With MCM41-NH-PW as catalyst, H2O2as oxidant and acetonitrile as extractant, the main factors affecting the desulfurization process were investigated, including temperature, the amount of catalyst and oxidizing agent, and the pre-reaction time, obtaining finally the optimum experimental conditions (catalyst dosage,1%the mass of normal octane; O/S molar ratio,15; pre-reaction time,5min; temperature,60℃; acetonitrile dosage,100%the volume of normal octane).It shows that the oxidation reactivity of different sulfur compounds was in the order of DBT>4.6-DMDBT> BT> TH. The result shows the electron density of sulfur compounds on the sulfur atoms and the space steric hindrance were two important factors in the ODS. Under the optimum experimental conditions, we studied the desulfurization efficiency of DBT in simulated fuel oil with EDTA-2Na as inhibitors. It showed that when10mL of EDTA-2Na were added to the reaction system, the desulfurization efficiency was obviously increased from96.8%to100%after180min. EDTA-2Na and trace metal ions can react to product the stable circular metal chelate. So there were no metal ions to catalyze the decomposition of hydrogen peroxide. The main reason is the production of the stable circular metal chelate. On the similar conditions, the catalyst of the1st and2nd recovered MCM41-NH-PW, the DBT conversion was obviously decreased. The catalyst of3rd and more time recovered MCM41-NH-PW, the DBT conversion was unchanged. When the MCM41-NH-PW was reused, the phosphotungstic acid was shedding, which were adsorbed on the surface of the catalyst, and the percent of unit mass heteropolyacids anion were reduced. Under the optimum experiment conditions and EDTA-2Na as inhibitors, we investigated the desulfurization efficiency of diesel with MCM41-NH-PW as catalyst. It shows that S-content in diesel decreased from496ppmw to49.2ppmw, the desulfurization efficiency90.1%and the recovery rate96.2%.Kinetics of the process catalyzed by four kinds of heteropolyacid compounds were studied, from which the reaction order were found to be1to DBT and the activation energy of reaction was found to be from45.2to49.4kJ/mol. It was found that heteropolyacids anion were be oxidized by H2O2, and the production of them were peracetic heteropolyacids anion by FTIR. Then, the peracetic heteropolyacids oxidized the sulfur atom in the sulfur compounds. And the oxidation of sulfur atoms were determined by the electron density of sulfur compounds on the sulfur atoms and the space steric hindrance. It was found that the DBT sulfone was only production on ODS and it was soluble in acetonitrile to achieve desulfurization.更多还原