LIQUID PHASE CO-OXIDATION OF THIOPHENOL AND STYRENE BY OXYGEN AND t-BUTYL HYDROPEROXIDE

Instability problems in both shale and petroleum derived middle distillate jet fuels have been correlated with the presence of peroxidic species. Although a good body of knowledge exists concerning the formation of peroxides in the liquid phase, relatively little is known about the reaction/ decomposition pathways available when other functional groups are present, since sulfur is the most abundant heteroatam present in jet fuels, the reaction of t-butyl hydroperoxide (tBKP) and/or oxygen with thiophenol in the presence of the active olefin, styrene, was examined in deaerated benzene at 120°C. The complex product mixture was analyzed by combined capillary column GC/MS. Major products included acetone, t-butanol and isdbutylene from the tBHP. Thiophenol and styrene combined to form addition products. Phenyl disulfide was observed from the thiophenol. The results indicated that although the product slate was complex, it was possible to explain the product mix in terms of a few competing reactions.     

LIQUID PHASE CO-OXIDATION OF THIOPHENOL AND STYRENE BY OXYGEN AND t-BUTYL HYDROPEROXIDE

ABSTRACT

Instability problems in both shale and petroleum derived middle distillate jet fuels have been correlated with the presence of peroxidic species. Although a good body of knowledge exists concerning the formation of peroxides in the liquid phase, relatively little is known about the reaction/ decomposition pathways available when other functional groups are present, since sulfur is the most abundant heteroatam present in jet fuels, the reaction of t-butyl hydroperoxide (tBKP) and/or oxygen with thiophenol in the presence of the active olefin, styrene, was examined in deaerated benzene at 120°C. The complex product mixture was analyzed by combined capillary column GC/MS. Major products included acetone, t-butanol and isdbutylene from the tBHP. Thiophenol and styrene combined to form addition products. Phenyl disulfide was observed from the thiophenol. The results indicated that although the product slate was complex, it was possible to explain the product mix in terms of a few competing reactions.     

LIQUID PHASE OXIDATION OF HEXYLDISULFIDE BY t-BUTYL HYDROPEROXIDE IN BENZENE

There are inconsistencies in the literature regarding the role of organosulfur compounds in general, and sulfonic acids in particular, on the oxidative instability of middle distillate fuels. Comparison of published results between investigations is complicated by differences in a large number of variables. Variations in fuel composition, heteroatam distribution, reaction surface, hydroperoxide concentration, dissolved oxygen and reaction temperature all contribute to the variation in observed results. In an effort to clarify this situation, we have examined the t-butyl hydroperoxide liquid phase oxidation of hexyldisulfide in deaerated benzene.     

LIQUID PHASE OXIDATION OF HEXYLDISULFIDE BY t-BUTYL HYDROPEROXIDE IN BENZENE

ABSTRACT

There are inconsistencies in the literature regarding the role of organosulfur compounds in general, and sulfonic acids in particular, on the oxidative instability of middle distillate fuels. Comparison of published results between investigations is complicated by differences in a large number of variables. Variations in fuel composition, heteroatam distribution, reaction surface, hydroperoxide concentration, dissolved oxygen and reaction temperature all contribute to the variation in observed results. In an effort to clarify this situation, we have examined the t-butyl hydroperoxide liquid phase oxidation of hexyldisulfide in deaerated benzene.     

LIQUID PHASE OXIDATION OF OCTANAL BY CUMENE HYDROPEROXIDE

Reactions that lead to fuel instability can be closely linked to the presence of active oxygen species. An increasing body of evidence links oxidation reactions of hydroperoxides to the instability observed in fuels. The active oxygen compounds present in fuels are alkyl and aromatic hydroperoxides. Cumene hydroperoxide represents a logical choice for an active oxygen compound that could be present in a middle distillate fuel. This paper reports on the reactions of cumene hydroperoxide with octanal in benzene solvent at 140°C for various time periods. The complete slate of products is presented along with a suggested mechanism to explain the observed products and the implications for fuel instability reactions.     

FUEL INSTABILITY STUDIES: LIQUID PHASE OXIDATION OF TETRAHYDROTHIOPHENE BY TERT-BUTYL HYDROPEROXIDE

ABSTRACT

The reactions that lead to fuel instability are the subject of conflicting reports in the literature. Confusion results from the difficulty in relating differences in fuel composition, temperature, surface effects and dissolved oxygen content that comprise the multitude of reported studies. Model studies offer a means by which the mechanism of an individual reaction can be related to a simple system and then extended to the more complex fuel media. This paper reports a model oxidation study of a cyclic sulfide, tetrahydrothiophene, with an active oxygen species, t-butyl hydroperoxide under mild reaction conditions, 120°C, in a tetradecane model fuel. The major oxidation product was tetrahydrothiophene sulfoxide from the sulfide and t-butanol from the hydroperoxide. The complete suite of products is reported.     

FUEL INSTABILITY STUDIES: LIQUID PHASE OXIDATION OF TETRAHYDROTHIOPHENE BY TERT-BUTYL HYDROPEROXIDE

The reactions that lead to fuel instability are the subject of conflicting reports in the literature. Confusion results from the difficulty in relating differences in fuel composition, temperature, surface effects and dissolved oxygen content that comprise the multitude of reported studies. Model studies offer a means by which the mechanism of an individual reaction can be related to a simple system and then extended to the more complex fuel media. This paper reports a model oxidation study of a cyclic sulfide, tetrahydrothiophene, with an active oxygen species, t-butyl hydroperoxide under mild reaction conditions, 120°C, in a tetradecane model fuel. The major oxidation product was tetrahydrothiophene sulfoxide from the sulfide and t-butanol from the hydroperoxide. The complete suite of products is reported.     

液相空气氧化法制备氟代苯甲酸工艺研究

从氟代甲苯出发,以醋酸为溶剂,采用液相空气氧化法,在钴锰盐和1,1,2,2-四溴乙烷催化体系存在下,合成了氟代苯甲酸,采用升华方法进行精制。探讨了反应压力、催化剂配比及用量、溶剂比及溶剂浓度对氧化反应的影响,当反应压力为0.8～1.0 MPa、反应温度160～220℃、溶剂比4:1,钴锰催化剂质量比为2:1时,反应转化率接近100％;在真空度98 kPa下升华,总质量收率大于97％。     

液相催化氧化3-甲基吡啶制备烟酸

在反应温度为170～180℃、压力为1．5 MPa时,在钴盐、锰盐、溴化物和自由基引发剂存在下,由氧气氧化3-甲基吡啶制备烟酸,产率为81．3%;以乙酸和芳香性卤代烃的混合物做溶剂时,对不锈钢反应釜没有腐蚀作用,其中乙酸的含量保持在15%～20%。     

改性钒磷氧化物催化剂液相选择性氧化环己烷

用浸渍法制备了Fe,Co,Ni,Bi改性的钒磷氧化物(VPO)催化剂,对催化剂进行了XRD和SEM表征,用氧化还原滴定法测定了不同晶相催化剂中钒的平均价态,并以环己烷为原料、H_2O_2,为氧化剂,考察了金属改性对VPO催化剂液相催化氧化环己烷合成环己酮性能的影响。结果表明,几种催化剂对液相催化氧化环己烷合成环己酮反应的催化活性由大到小的顺序为:Bi-VPOFe-VPONi-VPOCo-VPOVPO。在环己烷用量0.6 mL、丙酮用量10mL、催化剂Bi-VPO加量0.015g、H_2O_2,用量3mL、65℃、反应时间8h的条件下,环己烷转化率为81.4%,环己酮和环己醇收率分别为58.2%和23.2%。     

氢氧直接合成的过氧化氢原位氧化反应研究进展

过氧化氢（H₂O₂）的活性氧含量高且降解时副产物只有水,可作为工业常用氧化剂的替代物。H₂和O₂直接合成H₂O₂是一种高原子利用效率的绿色合成新技术,有望替代当前传统的工业生产方式,实现H₂O₂清洁生产与原位选择性氧化的一步集成。综述了H₂和O₂直接合成H₂O₂与丙烯环氧化、Fenton废水处理、甲烷氧化等反应的集成,介绍现已取得的成果及面临的挑战,拓宽H2、O2和有机物的原位氧化反应体系,为未来化学品的绿色合成提供新思路。     

氧气直接催化氧化苯酚合成对苯醌

以乙醇为溶剂,铜锂复合金属离子为催化剂,用氧气直接催化氧化苯酚合成对苯醌。考察了催化剂配比、催化剂与苯酚质量比、反应压力、反应温度和反应时间对苯酚催化氧化反应的影响。确定了苯酚催化氧化制备对苯醌的最优工艺条件为:n(Cu~(2+)):n(Li~+)=1:3,m(催化剂):m(苯酚)=1:2,温度80℃,压力2.7 MPa,反应时间3 h。在此反应条件下,苯酚转化率达85.50%,对苯醌选择性可达83.15%。     

甲苯液相催化氧化制苯甲醛绿色工艺研究进展

针对近几年国内外甲苯液相催化氧化制苯甲醛绿色工艺的新进展进行了综述,介绍了甲苯的H2O2氧化工艺及甲苯分子氧氧化工艺,重点介绍了工艺所用催化剂如钴系、锰系和钒系催化剂,指出钴氧化物或锰分子筛负载的纳米金催化剂在甲苯液相催化氧化研究中有潜在的应用前景.     

A MODEL STUDY OF THE OXIDATION OF UNDECYLENIC ACID BY TERT-BUTYL HYDROPEROXIDE: FUEL INSTABILITY REACTIONS

ABSTRACT

The subject of fuel instability reactions is usually complicated in that no one species is entirely responsible. Thus multi-component model systems need to be employed to simplify the study of alternate mechanisms and pathways. If the system is too complicated, the reaction pathways are too varied and complicated to discern. Additionally, the suite of heteroatoms present in a finished fuel depends on the source of the crude. Model systems thus represent a reasonable alternative. The model system employed in this study consists of tert-butyl hydroperoxide, and undecylenic acid in benzene solvent. Although radical mechanisms are complex, the slate of products was explainable by a few competing reactions.     

邻二甲苯液相氧化制邻甲基苯甲酸反应条件的考察

对采用空气作氧化剂,环烷酸钴作催化剂,由邻二甲苯液相氧化制备邻甲基苯甲酸的反应条件,在中型半连续鼓泡床反应器上,评价了反应温度、反应压力、空气流量以及反应时间对产物邻甲基苯甲酸单程质量收率的影响。结果表明,在１３０℃、ＭＰａ、空气流量０．８ｍ＾３／ｈ反应时间５ｈ的试验条件下,邻甲基苯酸单程质量收率为４３．２％。     

A MODEL STUDY OF THE OXIDATION OF UNDECYLENIC ACID BY TERT-BUTYL HYDROPEROXIDE: FUEL INSTABILITY REACTIONS

The subject of fuel instability reactions is usually complicated in that no one species is entirely responsible. Thus multi-component model systems need to be employed to simplify the study of alternate mechanisms and pathways. If the system is too complicated, the reaction pathways are too varied and complicated to discern. Additionally, the suite of heteroatoms present in a finished fuel depends on the source of the crude. Model systems thus represent a reasonable alternative. The model system employed in this study consists of tert-butyl hydroperoxide, and undecylenic acid in benzene solvent. Although radical mechanisms are complex, the slate of products was explainable by a few competing reactions.     

氧气一步氧化合成硫化促进剂TMTD

通过对目前国内外TMTD各种生产方法的比较,认为氧气一步氧化法较好。利用正交试验对氧气一步氧化法进行了研究,得到的最佳方案为反应温度40℃、压力0.5MPa、催化剂用量0.4mol/kmol二甲胺、原料配比二甲胺:二硫化碳=1:1.2(mol比)。     

有机概念图及IOB值的反向液相色谱法标定

介绍了有机概念图的意义与应用,并在岛津LC-6A液相色谱仪上应用反向液相色谱法建立了某些系列化合物保留时间与无机性有机平衡值(IOB)之间的关系。从而提供了以实验方法标定有机物或化工产品组分的IOB值,由此可推测其性质与用途。     

反相液相色谱法测定聚醚中的聚乙二醇

采用反相液相色谱技术,建立了纺织油剂聚醚中聚乙二醇的测定方法。     

苯和乙烯液相烷基化合成乙苯的研究及其新工艺的开发

报道了苯和乙烯在ＡＥＢ型分子筛催化剂上进行液相烷基化反应合成乙苯的研究开发结果。通过研究反应温度、压力、苯／惭烯摩尔比及空速等反应条件对烷基化反应过程的影响,确定了适当的反应条件。进行了苯和乙烯液相烷基化的２０００ｈ活性稳定性试验,乙烯转化率、乙苯选择性、惭基化选择性分别平均为１００％、９４．５％和９９．０％。进行了苯和多乙苯液相烷基转移反 的２０００ｈ活性稳定性试验,二乙苯转化率、多乙苯转化率、