DETERMINATION OF NITROGEN COMPOUND DISTRIBUTION FROM THREE SOURCE FUELS

ABSTRACT

As part of a world-wide survey of middle distillate fuel instability, three fuels were chosen for detailed GC/MS analysis. These fuels are identified by number and country of origin; FL-2577 was from Burnaby, British Columbia, Canada; FL-2599 was from Abamadj, Kuwait; and FL 2592 was from Chiba, Japan. The organo-nitrogen compounds in the three fuels were separated by mild acid extraction followed by silica gel absorption. This treatment yielded three fractions for each fuel; a basic nitrogen compounds fraction, BNC; a non-basic nitrogen compounds fraction in methylene chloride, mcl, NBNC-mcl; and a non-basic nitrogen compounds fraction in methanol, meoh, NBNC-meoh. The three fractions from each fuel were analyzed by combined capillary gc/ms. The organo-nitrogen compounds from each fraction were identified and quantitated.     

NITROGEN COMPOUND DISTRIBUTION AND FUEL INCOMPATIBILITY REACTIONS IN A TAR SAND DERIVED MIDDLE DISTILLATE FUEL

A high paraffin, high nitrogen, low sulfur jet fuel derived from Athabasca tar sands was studied. The organo-nitrogen compounds in the fuel were isolated by mild acid extraction followed by silica-gel adsorption. Three extracts were derived from this fuel: a basic nitrogen compounds extract, BNC, in methylene chloride, a non-basic nitrogen compounds extract, NBNC, in methyl alcohol and an NBNC extract in methylene chloride. The major constituents of each extract were identified and quantitated by combined capillary column GC/MS. Alkyl substituted pyrroles, pyridines, indoles, tetrahydro-quinolines, carbazoles, and quinolines were the prevalent organo-nitrogen compounds present. Incompatibility tests were conducted on this fuel using the oxygen overpressure method with both doped and undoped fuel systems. The dopant of choice was cumene hydroperoxide. Practically no sediment formation was observed for the undoped fuel (0.1 mg/100mL fuel). The doped fuel matrix induced incompatibility behavior in proportion to the quantity of dopant present.     

Nitrogen Compound Distribution of Refined Middle Distillate Fuels

Abstract

Three middle distillate fuels originating from New Zealand, Venezuela, and Texas were studied to determine the nitrogen compound distribution in each fuel. Organo-nitrogen compounds in the fuels were isolated by mild acid extraction followed by silica gel adsorption. The extraction scheme yielded three extracts for each fuel—a basic nitrogen extract in methylene chloride, a non-basic nitrogen extract in methyl alcohol, and a non-basic nitrogen extract in methylene chloride. The major constituents of each extract were identified by gas chromatography/mass spectrometry (GC/MS).     

Nitrogen Compound Distribution of Refined Middle Distillate Fuels

Three middle distillate fuels originating from New Zealand, Venezuela, and Texas were studied to determine the nitrogen compound distribution in each fuel. Organo-nitrogen compounds in the fuels were isolated by mild acid extraction followed by silica gel adsorption. The extraction scheme yielded three extracts for each fuel—a basic nitrogen extract in methylene chloride, a non-basic nitrogen extract in methyl alcohol, and a non-basic nitrogen extract in methylene chloride. The major constituents of each extract were identified by gas chromatography/mass spectrometry (GC/MS).     

煤焦油和石油基柴油馏分中含氮化合物的分离鉴定

对两种煤焦油柴油馏分和催化裂化柴油、焦化柴油、直馏柴油中的含氮化合物做了鉴定分析。采用硅胶柱分离富集5种柴油中的非碱性含氮化合物,酸萃取法萃取碱性含氮化合物,利用GC/MS分离定性。结果表明：煤焦油柴油馏分中非碱性含氮化合物主要是咔唑和吲哚类化合物,碱性含氮化合物以喹啉、吡啶和苯胺类为主;催化裂化柴油以咔唑和吲哚类非碱性含氮化合物为主;焦化柴油以吡啶和喹啉类碱性含氮化合物为主;直馏柴油中主要是咔唑类非碱性含氮化合物,还有少量的喹啉和苯胺类碱性含氮化合物。煤焦油柴油馏分和焦化柴油以碱性含氮化合物为主,催化裂化柴油和直馏柴油以非碱性含氮化合物为主,煤焦油柴油馏分中的碱性含氮化合物种类及含量远高于石油馏分。     

柴油的储存安定性研究

用2，5—二甲基吡咯、四氢咔唑代表非碱性氮化合物，2—甲基吡啶、2—甲基喹啉代表碱性氮化合物，苯乙烯代表不饱和烃，苯甲酸、环烷酸、l—萘酚、对甲苯磺酸、邻甲苯硫酚代表酸性化合物和含硫化合物。将这些化合物单独和以各种组合形式加入直馏柴油中，观察它们对柴油安定性的影响。结果表明，除2，5—二甲基吡咯外，其它化合物在没有非碱性氮化合物的催化作用下，对柴油安定性的影响很小。2，5—二甲基吡咯与酸性化合物共同作用，对柴油的安定性影响最大，特别是它与对甲苯磺酸、l—萘酚共同作用时，对柴油安定性的影响要远大于与烷基和环烷基酸性化合物共同作用的影响。传统的由酚类和胺类抗氧剂为主的安定性添加剂，对含有较多类似2，5—二甲基吡咯类的非碱性化合物引起的柴油的不安定是无效的。新研制的柴油安定性添加剂对抑制由非碱性化合物引起的催化裂化柴油的颜色变深和沉渣生成有较好的效果。     

Nitrogen Compound Distribution in Refined Middle Distillate Fuels

Abstract

Three diverse middle distillate fuels from Mobile, Alabama, Jacksonville, Florida, and Kirachi, Pakistan were analyzed to quantify the organic nitrogen compound distribution in each. Organo-nitrogen compounds were isolated by a mild acid extraction followed by a silica-gel adsorption procedure. The extraction process yielded three extracts for each fuel: a basic nitrogen extract in methylene chloride, a nonbasic nitrogen extract in methylene chloride, and a nonbasic nitrogen extract in methanol. The major compounds in each extract were identified by gas chromatography/mass spectrometry (GC/MS).     

Nitrogen Compound Determination and Distribution in Three Source Fuels by GC/MS

Abstract

Three middle distillate fuels from Kenya, Kuwait, and Sweden were studied for the identification and comparison of their nitrogen content. The organic nitrogen compounds were isolated by mild acid extraction, and three extracts were obtained from each source fuel: a basic nitrogen extract in methylene chloride (BNC), a nonbasic nitrogen extract in methylene chloride (NBNC), and a nonbasic nitrogen extract in methanol (NBNC). The major constituents of each extract were determined by gas chromatography/mass spectrometry (GC/MS). The largest number of nitrogen compounds of the BNC extracts were pyridines and pyrroles in the Kuwait fuel, indoles and pyrroles in the Swedish fuel, and pyrroles and quinolines in the Kenya fuel. The Kenya fuel had carbazoles present in the BNC extract, whereas, the other two fuels didn’t have this compound. The predominant organic nitrogen compounds in the NBNC extracts in methylene chloride for Kuwait and Kenya were tetrahydroquinolines and quinolines, respectively. The analysis of the NBNC extracts in methanol showed the following prevalent organic nitrogen compounds: indoles for Kuwait, quinolines for Sweden, and pyrroles for Kenya. All three fuels had short chain alkyl substituted indoles. Kenya had the lowest nitrogen content, followed by Kuwait and Sweden.     

Nitrogen Compound Determination and Distribution in Three Source Fuels by GC/MS

Three middle distillate fuels from Kenya, Kuwait, and Sweden were studied for the identification and comparison of their nitrogen content. The organic nitrogen compounds were isolated by mild acid extraction, and three extracts were obtained from each source fuel: a basic nitrogen extract in methylene chloride (BNC), a nonbasic nitrogen extract in methylene chloride (NBNC), and a nonbasic nitrogen extract in methanol (NBNC). The major constituents of each extract were determined by gas chromatography/mass spectrometry (GC/MS). The largest number of nitrogen compounds of the BNC extracts were pyridines and pyrroles in the Kuwait fuel, indoles and pyrroles in the Swedish fuel, and pyrroles and quinolines in the Kenya fuel. The Kenya fuel had carbazoles present in the BNC extract, whereas, the other two fuels didn't have this compound. The predominant organic nitrogen compounds in the NBNC extracts in methylene chloride for Kuwait and Kenya were tetrahydroquinolines and quinolines, respectively. The analysis of the NBNC extracts in methanol showed the following prevalent organic nitrogen compounds: indoles for Kuwait, quinolines for Sweden, and pyrroles for Kenya. All three fuels had short chain alkyl substituted indoles. Kenya had the lowest nitrogen content, followed by Kuwait and Sweden.     

FUEL INSTABILITY STUDIES: THE REACTION OF 3-METHYL INDOLE WITH ARYL SULFONIC ACIDS

ABSTRACT

Incompatibility reactions in middle distillate fuels can be ascribed to the presence of specific polar heteroatomic compounds or species containing oxygen, sulfur, and nitrogen. It has been proposed that the observed sediment and/or gum formation results from the interaction of heteroatomic species with the acids contained in fuels. Recent studies have shown that the addition of non-basic nitrogen heterocycles such as indoles to a fuel increases deposit formation dramatically. Therefore, an attempt was made to identify the structure of the sediment. This paper reports on the reaction of 3-methyl indole with aryl sulfonic acids. The results of this study were accomplished by identifying the nature and the structure of the sediments formed using elemental analysis and various instrumental techniques.     

FUEL INSTABILITY STUDIES: THE REACTION OF 3-METHYL INDOLE WITH ARYL SULFONIC ACIDS

Incompatibility reactions in middle distillate fuels can be ascribed to the presence of specific polar heteroatomic compounds or species containing oxygen, sulfur, and nitrogen. It has been proposed that the observed sediment and/or gum formation results from the interaction of heteroatomic species with the acids contained in fuels. Recent studies have shown that the addition of non-basic nitrogen heterocycles such as indoles to a fuel increases deposit formation dramatically. Therefore, an attempt was made to identify the structure of the sediment. This paper reports on the reaction of 3-methyl indole with aryl sulfonic acids. The results of this study were accomplished by identifying the nature and the structure of the sediments formed using elemental analysis and various instrumental techniques.     

Removing Organic Nitrogen Compounds From Middle Distillate Fuels with a Catalyst Used as a Filtering Media

Abstract

Fuel storage instability reactions of middle distillate fuel continue to be of great interest to the Department of Defense. Unlike civilian fuel, military fuel typically remains in storage tanks for one or more years. As fuel is removed from these tanks, the tanks are subsequently filled with more recently purchased fuel. In many cases, the mixed fuel is not compatible, resulting in chemical sediment and sludge formation. This fuel incompatibility can result in chemical degradation reactions that form solids that will plug nozzles and filters and render the entire contents of the storage tank unusable. Previous research has shown that polar organic nitrogen functional groups are involved in fuel instability reactions. These organo-nitrogen compounds are difficult and expensive to completely remove during the refining process; hence, this investigation involved the removal of these compounds employing three heterogeneous catalyst systems and combinations of these systems as filtering media. An unstable fuel was treated separately with Sc₂O₃, Cu/Sc₂O₃, fullerene (F), a 1:1 ratio of Sc₂O₃:(F), and a 1:1 ratio of Cu/Sc₂O₃:(F). The composition of the filtrates after filtering with the different catalytic systems was analyzed by combined gas chromatography/mass spectrometry (GC/MS). The results of this study showed that after treating the fuel with the catalyst systems, the organic nitrogen compounds detected in the extract were 0.29% carbazoles, 18.2% indoles, and 1.0% for both pyrroles and tetrahydroquinolines, and neither pyridines nor quinolines were detected. This investigation showed that scandium oxide, which is a recycled catalyst, is capable of removing organic nitrogen compounds from fuels.     

Analytical Profile of Organo-nitrogen Compounds in Gulf Coast Refined Fuels by GC/MS

Abstract

This study examines the composition of two samples of crude fuels originating from the Gulf Coastal areas of the United States. Both nitrogen-containing basic compounds as well as non-basic hydrocarbon compounds were evaluated for presence and relative amount in these two samples. The extractions of the basic nitrogenous compounds were achieved with weak acid extractions. The basic nitrogenous compounds, due to emulsification, formed two distinct fractions. The nitrogenous based-compounds were comprised of pyridines, quinolines, tetrahydroquinolines, indoles, and carbazoles to varying amounts. The hydrocarbon content in each of the two fuels analyzed was found to contain mostly naphthols.     

Analytical Profile of Organo-nitrogen Compounds in Gulf Coast Refined Fuels by GC/MS

This study examines the composition of two samples of crude fuels originating from the Gulf Coastal areas of the United States. Both nitrogen-containing basic compounds as well as non-basic hydrocarbon compounds were evaluated for presence and relative amount in these two samples. The extractions of the basic nitrogenous compounds were achieved with weak acid extractions. The basic nitrogenous compounds, due to emulsification, formed two distinct fractions. The nitrogenous based-compounds were comprised of pyridines, quinolines, tetrahydroquinolines, indoles, and carbazoles to varying amounts. The hydrocarbon content in each of the two fuels analyzed was found to contain mostly naphthols.     

气相色谱/微库仑法研究催化柴油及其加氢生成油中氮化物类型和分布

本文用气相色谱/微库仑法首次对催化柴油及其加氢精制生成油的碱性氮化物和中性氮化物的类型与分布进行了较完整的研究。发现催化柴油中碱性氮化物主要是苯胺类和喹啉类,中性氮化物主要是吲哚类和咔唑类。中性氮化物约为碱性氮化物的3～5倍。四种催化柴油中各氮化物类型占总氮的相对百分数基本上在同一水平。加氢精制条件选择适当,碱性氮中喹啉类能全部脱除,中性氮中吲哚类可显著减少。文中中性氮不经抽提浓缩,直接注样,避免了中性氮抽提浓缩所引起的显著误差。     

催化裂化柴油中含氮化合物类型分布

采用中性硅胶柱分离、富集催化裂化柴油中的含氮化合物,进一步用酸改性硅胶柱将含氮化合物分离成碱性含氮化合物和中性含氮化合物,利用GC-MS进行定性分析,结合含氮化合物的GC保留特性和沸点分布规律,确定催化裂化柴油中含氮化合物的类型,利用GC-NCD进行定量分析。结果表明：催化裂化柴油中的含氮化合物主要是中性含氮化合物和少量碱性含氮化合物,中性含氮化合物占90%以上,主要是吲哚类和咔唑类含氮化合物,不同来源催化裂化柴油中中性含氮化合物的类型分布并不相同;碱性含氮化合物仅占10%左右,主要是苯胺类、喹啉类和苯并喹啉类含氮化合物。     

直馏柴油和焦化柴油中含氮化合物类型分布

采用中性硅胶柱分离、富集直馏柴油和焦化柴油中的含氮化合物,进一步用酸改性硅胶柱将含氮化合物分离成碱性含氮化合物和中性含氮化合物,利用GC-MS定性,结合含氮化合物的GC保留特性和沸点分布规律,确定直馏柴油和焦化柴油中含氮化合物的类型。结果表明,直馏柴油中中性含氮化合物占总含氮化合物的质量分数在70%以上,主要是苯并咔唑类含氮化合物;焦化柴油中含氮化合物包括吡啶类、苯胺类、吲哚类、喹啉类和咔唑类等含氮化合物,其中中性含氮化合物的含量比碱性含氮化合物稍高,占总含氮化合物的质量分数在50%以上。     

非碱性氮化物催化裂化转化规律及反应化学研究

采用小型固定流化床装置,考察以吲哚为代表的非碱性氮化物对催化裂化过程的影响,以及非碱性氮化物在催化裂化过程中的分布规律和反应化学。结果表明：非碱性氮化物的加入会导致反应转化率下降,并影响产物分布,且加入量越大,影响越大;吲哚经过催化裂化反应,原料油中54.15%的氮分布于柴油馏分中,24.88%的氮转化到焦炭中,12.58%的氮分布于汽油馏分中,4.46%的氮转化为氨气,进入重油馏分中的氮不足5%;吲哚在催化裂化过程中最易发生烷基化反应,吲哚分子中氮环更易通过氢转移反应被饱和,进而发生开环裂化反应生成苯胺类氮化物和氨气;烯烃和氨气可通过环化缩合反应生成苯胺及喹啉类六元氮杂环化合物;小分子氮杂环化合物可发生烷基化、环化缩合反应生成大分子氮化物。     

不同产地页岩油的组成分析

采用柱层断分离方法,以经过处理的硅胶为吸附剂,依次用正已烷,甲苯,乙酸乙酯,甲醇为洗脱剂对内陆和海底两个不同产地的页岩油分别预分离为4个馏分。使用不同极性交联毛细管色谱柱,将各馏分分别进行色谱分离,并且用GC－MS进行了组分定性。根据各馏分的收率,结合馏分中各组分色谱峰面积归一法进行了组分的定量。在内陆页岩油中共测得质量分数大于0．2％的组分269个,其中各种烃类化合物约占79％（烷烃,烯烃和环烷烃共为52％）,其它为各种含硫,氮和氧的化合物。在海底页岩油中共测得质量分数大于0．02％的组分284个,其中各种烃类化合物约占60％（烷烃,烯烃和环烷烃共为29％）,还含有大量的含氧化合物（约占29％,主要为各种烷基酚）,其它为含硫,含氮化合物。     

塔里木盆地原油中氮化物的分离及鉴定

由于原油中氮化物含量低且组成复杂，在用仪器分析其特征之前需要进行浓缩和预分离。采用柱液相色谱对塔里木盆地原油样品中的含氮化合物进行了分离，首先用中性氧化铝将原油分成饱和烃，芳烃和富氮馏份；然后用硅酸将富氮馏份进一步分离，得到了中性吡咯氮，和碱性吡啶等馏分。