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Suoqi Zhao - One of the best experts on this subject based on the ideXlab platform.
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specificatIon of the nitrogen functIonal group in a hydrotreated petroleum molecule using hydrogen deuterium exchange Electrospray IonizatIon high resolutIon mass spectrometry
Analyst, 2020Co-Authors: Ying Zhang, Quan Shi, Xiu Chen, Linzhou Zhang, Suoqi ZhaoAbstract:Hydrotreatment is extensively used for the productIon of clean fuel. Attaining an understanding of the structural conversIon of the nitrogen species during hydrotreatment is very challenging due to the compositIonal complexity and the absence of a proper characterizatIon method. In the presented work, we coupled hydrogen/deuterium exchange (HDX) with Positive-Ion Electrospray IonizatIon high-resolutIon mass spectrometry ((+) ESI HR MS) to investigate the difference between the compositIon of the nitrogen-containing species and the functIonal groups before and after hydrotreatment. The solvent and additive were optimized for HDX (+) ESI HRMS through systematic evaluatIons on model nitrogen-containing compounds. We found that adding deuterated water (D2O) and deuterated formic acid (DCOOD) significantly increased the degree of HDX and thus facilitated the identificatIon of nitrogen functIonal groups. After applicatIon to the hydrotreated petroleum samples, the compositIonal variatIon of intermediate amine compounds during the heavy petroleum hydrotreatment process was clearly revealed.
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separatIon and characterizatIon of sulfur compounds in ultra deep formatIon crude oils from tarim basin
Energy & Fuels, 2015Co-Authors: Meng Wang, Suoqi Zhao, Guangyou Zhu, Limin Ren, Xuxia Liu, Quan ShiAbstract:Sulfur compounds in two representative deep crude oils (Ha9, 6598–6710 m; ZS1C, 6861–6944 m) with distinct levels of maturity from Tarim Basin, China, were analyzed by Positive-Ion Electrospray IonizatIon (ESI) Fourier transform Ion cyclotron resonance mass spectrometry (FT-ICR MS). The thiophenic and sulfidic compounds were selectively separated from the crude oils with high purity and recovery by the methylatIon/demethylatIon approach and further characterized in detail by gas chromatography (GC) coupled with a sulfur chemiluminescence detector (SCD) and GC–mass spectrometry (MS). The two crude oils have a large difference in sulfur compound compositIon, which are both unique compared to common crude oils. A homologue series of 1,1-dimethylhexahydrodibenzothiophenes, which has been found as highly resistant organic sulfur compounds in diesel hydrodesulfurizatIon, was detected in Ha9 crude oil. This is the first time that these biomarker-like compounds have been identified in crude oil. Thiadiamondoids (...
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characterizatIon of heavy petroleum fractIon by Positive Ion Electrospray IonizatIon ft icr mass spectrometry and collisIon induced dissociatIon bond dissociatIon behavior and aromatic ring architecture of basic nitrogen compounds
Science China-chemistry, 2013Co-Authors: Linzhou Zhang, Yahe Zhang, Suoqi Zhao, Keng H Chung, Quan ShiAbstract:This paper examined the bond dissociatIon behavior and aromatic ring architecture of basic nitrogen compounds in Sudan heavy petroleum fractIon. Both broadband and quadrupole isolatIon modes Positive-Ion Electrospray IonizatIon (ESI) Fourier transform Ion cyclotron resonance mass spectrometry (FT-ICR MS) coupled with collisIon induced dissociatIon (CID) techniques were used to characterize a low sulfur crude oil derived vacuum residuum (VR). The appropriate CID operating conditIon was selected by comparing the molecular weight distributIons of the basic nitrogen compounds under various CID operating conditIons. Both odd- and even-electron fragment Ions were observed from the mass spectrum, indicating that the heterolytic and homolytic bond cleavages occurred simultaneously during the CID process. The odd-electron fragment Ions were predominant in each class species, indicating preferential heterolytic bond cleavages. At the optimal CID conditIon, the alkyl groups decomposed deeply and just left the aromatic cores of the nitrogen compounds. No significant variatIon in double bond equivalent (DBE) value was observed between the fragment and parent Ions, revealing that the dominatIon of single core structure.
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distributIon of sulfides and thiophenic compounds in vgo subfractIons characterized by Positive Ion Electrospray fourier transform Ion cyclotron resonance mass spectrometry
Energy & Fuels, 2011Co-Authors: Peng Liu, Yahe Zhang, Keng H Chung, Quan Shi, Na Pan, Suoqi ZhaoAbstract:Detailed elemental compositIon and distributIon of sulfides and thiophenic compounds in four subfractIons of Kazakhstan vacuum gas oil (VGO) were determined by Positive Ion Electrospray (ESI) Fourier transform Ion cyclotron resonance mass spectrometry (FT-ICR MS). The sulfides in VGO subfractIons were selectively oxidized into sulfoxides using tetrabutylammonium periodate (TBAPI). The sulfur compounds in the oxidized VGO subfractIons were reacted by methylatIon to form methylsulfonium salts and were then characterized. Elemental compositIon and distributIon of sulfides and thiophenic compounds in the VGO subfractIons were characterized by their double bond equivalents (DBE) values and carbon numbers before and after the oxidatIon reactIons. The results showed that the S1 class species with DBE values of 6 and greater are likely thiophenic compounds, while those with DBE values less than 6 are sulfides. As boiling point of VGO increased, the abundance of thiophenic compounds increased. DBE value and carbon...
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molecular characterizatIon of sulfur compounds in venezuela crude oil and its sara fractIons by Electrospray IonizatIon fourier transform Ion cyclotron resonance mass spectrometry
Energy & Fuels, 2010Co-Authors: Keng H Chung, Suoqi Zhao, Yahe Zhang, Chunming XuAbstract:Venezuela crude oil was separated into saturates, aromatics, resins, and asphaltenes (SARA) fractIons. The sulfur compounds in the crude oil and its SARA fractIons were reacted with iodomethane in the presence of silver tetrafluoroborate and converted to methylsulfonium salts. The methylsulfonium salts were characterized by Positive-Ion Electrospray IonizatIon (ESI) and Fourier transform Ion cyclotron resonance mass spectrometry (FT-ICR MS). The S1, S2, S3, O1S1, O1S2, O2S1, and N1S1 class species were identified in crude oil derived methylsulfonium salts. The molecular compositIon and mass distributIon of sulfur compounds in the subfractIons were distinctly different. Small amounts of S1 class species (cyclic-ring sulfides) were present in the saturates fractIon. Thiophenic sulfur compounds were dominant in the aromatics fractIon. Complex multiheteroatoms (N1Sy, OxSy, and N1OxSy class species) were present in the resins and asphaltenes fractIons. The relative abundance plots of double-bond equivalence (D...
Quan Shi - One of the best experts on this subject based on the ideXlab platform.
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specificatIon of the nitrogen functIonal group in a hydrotreated petroleum molecule using hydrogen deuterium exchange Electrospray IonizatIon high resolutIon mass spectrometry
Analyst, 2020Co-Authors: Ying Zhang, Quan Shi, Xiu Chen, Linzhou Zhang, Suoqi ZhaoAbstract:Hydrotreatment is extensively used for the productIon of clean fuel. Attaining an understanding of the structural conversIon of the nitrogen species during hydrotreatment is very challenging due to the compositIonal complexity and the absence of a proper characterizatIon method. In the presented work, we coupled hydrogen/deuterium exchange (HDX) with Positive-Ion Electrospray IonizatIon high-resolutIon mass spectrometry ((+) ESI HR MS) to investigate the difference between the compositIon of the nitrogen-containing species and the functIonal groups before and after hydrotreatment. The solvent and additive were optimized for HDX (+) ESI HRMS through systematic evaluatIons on model nitrogen-containing compounds. We found that adding deuterated water (D2O) and deuterated formic acid (DCOOD) significantly increased the degree of HDX and thus facilitated the identificatIon of nitrogen functIonal groups. After applicatIon to the hydrotreated petroleum samples, the compositIonal variatIon of intermediate amine compounds during the heavy petroleum hydrotreatment process was clearly revealed.
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characterizatIon of vanadyl and nickel porphyrins enriched from heavy residues by Positive Ion Electrospray IonizatIon ft icr mass spectrometry
Energy & Fuels, 2015Co-Authors: He Liu, Quan Shi, Zongxian Wang, Aijun Guo, Kun ChenAbstract:Petroporphyrins were enriched and purified from atmospheric residues of two typical heavy oils, Canadian oil sand bitumen (OSAR: Ni, 80 ppm; V, 190 ppm; S, 3.97 wt %) and Chinese Liaohe heavy oil (...
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separatIon and characterizatIon of sulfur compounds in ultra deep formatIon crude oils from tarim basin
Energy & Fuels, 2015Co-Authors: Meng Wang, Suoqi Zhao, Guangyou Zhu, Limin Ren, Xuxia Liu, Quan ShiAbstract:Sulfur compounds in two representative deep crude oils (Ha9, 6598–6710 m; ZS1C, 6861–6944 m) with distinct levels of maturity from Tarim Basin, China, were analyzed by Positive-Ion Electrospray IonizatIon (ESI) Fourier transform Ion cyclotron resonance mass spectrometry (FT-ICR MS). The thiophenic and sulfidic compounds were selectively separated from the crude oils with high purity and recovery by the methylatIon/demethylatIon approach and further characterized in detail by gas chromatography (GC) coupled with a sulfur chemiluminescence detector (SCD) and GC–mass spectrometry (MS). The two crude oils have a large difference in sulfur compound compositIon, which are both unique compared to common crude oils. A homologue series of 1,1-dimethylhexahydrodibenzothiophenes, which has been found as highly resistant organic sulfur compounds in diesel hydrodesulfurizatIon, was detected in Ha9 crude oil. This is the first time that these biomarker-like compounds have been identified in crude oil. Thiadiamondoids (...
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new vanadium compounds in venezuela heavy crude oil detected by Positive Ion Electrospray IonizatIon fourier transform Ion cyclotron resonance mass spectrometry
Scientific Reports, 2015Co-Authors: Xu Zhao, Quan Shi, Murray R GrayAbstract:Metalloporphyrins are ubiquitous in nature, particularly iron porphyrins (hemes) and magnesium dihydroporphyrins or chlorophylls. Oxovanadium (IV) complexes of alkyl porphyrins are widely distributed in petroleum, oil shales and maturing sedimentary bitumen. Here we identify new vanadium compounds in Venezuela Orinoco heavy crude oil detected by Fourier transform-Ion cyclotron resonance mass spectrometry (FT-ICR MS). These compounds likely have the main structure of porphyrin, with the additIon of more aromatic rings, thiophene and amino functIonal groups, corresponding to molecular series of C(n)H(2n-40)N(4)V(1)O(1) (36 ≤ n ≤ 58),C(n)H(2n-42)N(4)V(1)O(1) (37 ≤ n ≤ 57),C(n)H(2n-44)N(4)V(1)O(1) (38 ≤ n ≤ 59),C(n)H(2n-46)N(4)V(1)O(1) (43 ≤ n ≤ 54),C(n)H(2n-48)N(4)V(1)O(1) (45 ≤ n ≤ 55),C(n)H(2n-38)N(4)V(1)S(1)O(1) (36 ≤ n ≤ 41),C(n)H(2n-40)N(4)V(1)S(1)O(1) (35 ≤ n ≤ 51),C(n)H(2n-42)N(4)V(1)S(1)O(1) (36 ≤ n ≤ 54),C(n)H(2n-44)N(4)V(1)S(1)O(1) (41 ≤ n ≤ 55),C(n)H(2n-46)N(4)V(1)S(1)O(1) (39 ≤ n ≤ 55),C(n)H(2n-27)N(5)V(1)O(1) (29 ≤ n ≤ 40),C(n)H(2n-29)N(5)V(1)O(1) (34 ≤ n ≤ 42),C(n)H(2n-33)N(5)V(1)O(1) (31 ≤ n ≤ 38),C(n)H(2n-35)N(5)V(1)O(1) (32 ≤ n ≤ 41),C(n)H(2n-27)N(5)V(1)O(2) (32 ≤ n ≤ 41) and C(n)H(2n-29)N(5)V(1)O(2) (33 ≤ n ≤ 42). These findings are significant for the understanding of the existing form of vanadium species in nature, and are helpful for enhancing the amount of informatIon on palaeoenvironments and improving the level of applied basic theory for the processing technologies of heavy oils.
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new vanadium compounds in venezuela heavy crude oil detected by Positive Ion Electrospray IonizatIon
2014Co-Authors: Xu Zhao, Quan Shi, Murray R GrayAbstract:Metalloporphyrins are ubiquitous in nature, particularly iron porphyrins (hemes) and magnesium dihydroporphyrins or chlorophylls. Oxovanadium (IV) complexes of alkyl porphyrins are widely distributed in petroleum, oil shales and maturing sedimentary bitumen. Here we identify new vanadium compounds in Venezuela Orinoco heavy crude oil detected by Fourier transform-Ion cyclotron resonance mass spectrometry (FT-ICR MS). These compounds likely have the main structure of porphyrin, with the additIon of more aromatic rings, thiophene and amino functIonal groups, corresponding to molecular series of CnH2n-40N4V1O1 (36 # n # 58),CnH2n-42N4V1O1 (37 # n # 57),CnH2n-44N4V1O1 (38 # n # 59),CnH2n-46N4V1O1 (43 # n # 54),CnH2n-48N4V1O1 (45 # n # 55),CnH2n-38N4V1S1O1 (36 # n # 41),CnH2n-40N4V1S1O1 (35 # n # 51),CnH2n-42N4V1S1O1 (36 # n # 54),CnH2n-44N4V1S1O1 (41 # n # 55),CnH2n-46N4V1S1O1 (39 # n # 55),CnH2n-27N5V1O1 (29 # n # 40),CnH2n-29N5V1O1 (34 # n # 42),CnH2n-33N5V1O1 (31 # n # 38),CnH2n-35N5V1O1 (32 # n # 41),CnH2n-27N5V1O2 (32 # n # 41) and CnH2n-29N5V1O2 (33 # n # 42). These findings are significant for the understanding of the existing form of vanadium species in nature, and are helpful for enhancing the amount of informatIon on palaeoenvironments and improving the level of applied basic theory for the processing technologies of heavy oils.
Alan G. Marshall - One of the best experts on this subject based on the ideXlab platform.
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Positive Ion Electrospray IonizatIon suppressIon in petroleum and complex mixtures
Energy & Fuels, 2018Co-Authors: Brian M Ruddy, Ryan P. Rodgers, Christopher L Hendrickson, Alan G. MarshallAbstract:Since the emergence of high resolving power crude oil mass spectrometry two decades ago, hundreds of publicatIons and presentatIons have detailed petroleum complex mixtures by Electrospray IonizatIon (ESI) mass spectrometry (MS). None of these works have reported or detailed Ion suppressIon (also referred to as IonizatIon biasing or matrix effects) which is a well-known feature of ESI. Here, we show the extreme consequences of IonizatIon biasing within a narrow, 1 order of magnitude concentratIon range for crude oil mixture direct infusIon experiments in Positive Ion (+) ESI. An oil spill contaminant, a crude oil, and an equimolar model compound mixture were Electrosprayed at various analyte and acid modifier concentratIons for Fourier transform Ion cyclotron resonance (FT-ICR) and time-of-flight (TOF) MS analysis. A 3-fold increase in the number of elemental compositIons is achieved by optimizatIon of analyte and acid concentratIon. At high analyte concentratIon, oxygen heteroatom class (i.e., CcHhOx spe...
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Lithium CatIonizatIon for Petroleum Analysis by Positive Ion Electrospray IonizatIon Fourier Transform Ion Cyclotron Resonance Mass Spectrometry
Energy & Fuels, 2014Co-Authors: Vladislav V. Lobodin, Ryan P. Rodgers, Priyanka Juyal, Amy M. Mckenna, Alan G. MarshallAbstract:Lithium catIonizatIon can significantly extend the compositIonal range for analysis of petroleum components by Positive Electrospray IonizatIon [(+) ESI], by accessing species that lack a basic nitrogen atom and, hence, are not seen by conventIonal (+) ESI that relies on protonatIon as the primary IonizatIon mechanism. Here, various solvent compositIons and lithium salts enabled us to optimize IonizatIon by formatIon of lithium adducts ([M + Li]+), and the results are compared to productIon of [M + H]+ by conventIonal (+) ESI with formic acid. Lithium catIonizatIon (+) ESI Fourier transform Ion cyclotron resonance mass spectrometry (FT-ICR MS) of Athabasca bitumen heavy vacuum gas oil (475–500 °C) and North and South American crude oils demonstrates considerable improvement over protonatIon for productIon of Ions from compounds belonging to SxOy (SO, SO2, SO3, SO4, S2O, S2O2, etc.) heteroatom classes. Those compounds exhibit much higher affinity for lithium catIon than for proton and yield abundant [M + L...
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silver catIonizatIon for rapid speciatIon of sulfur containing species in crude oils by Positive Electrospray IonizatIon fourier transform Ion cyclotron resonance mass spectrometry
Energy & Fuels, 2014Co-Authors: Vladislav V. Lobodin, Ryan P. Rodgers, Priyanka Juyal, Amy M. Mckenna, Alan G. MarshallAbstract:Silver catIonizatIon constitutes a complementary approach for analysis of petroleum components with Positive-Ion Electrospray IonizatIon (ESI) mass spectrometry and accesses species that lack a basic nitrogen atom and, hence, are not observed by conventIonal Positive ESI. Four samples of different origin [Canadian bitumen, Canadian bitumen heavy vacuum gas oil (HVGO; 475–500 °C) and South American and Middle East heavy crude oils, all high in sulfur content] were used to study silver catIonizatIon by (+) ESI. CatIonizatIon with Ag+ is essentially instantaneous and accesses hydrocarbons and nonpolar sulfur-containing heteroatom classes (e.g., Ss and SsOo), providing an attractive alternative to time-consuming derivatizatIon by S-methylatIon to Ionize sulfur-containing species. For each sample, we compare Ag+ catIonizatIon (+) ESI to conventIonal (+) ESI with formic acid to promote Ion formatIon. Other IonizatIon methods, such as chemical IonizatIon (CI), field desorptIon (FD), matrix-assisted laser desorpt...
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characterizatIon of athabasca bitumen heavy vacuum gas oil distillatIon cuts by negative Positive Electrospray IonizatIon and automated liquid injectIon field desorptIon IonizatIon fourier transform Ion cyclotron resonance mass spectrometry
Energy & Fuels, 2008Co-Authors: Donald F Smith, Ryan P. Rodgers, Parviz Rahimi, Alem Teclemariam, Alan G. MarshallAbstract:We have analyzed eight heavy vacuum gas oil (HVGO) distillatIon fractIons, initial boiling point (IBP)−343, 343−375, 375−400, 400−425, 425−450, 450−475, 475−500, and 500−525 °C, of an Athabasca bitumen by Fourier transform Ion cyclotron resonance mass spectrometry (FT-ICR MS). Acidic, basic, and nonpolar components were detected by negative-Ion and Positive-Ion Electrospray IonizatIon (ESI) and automated liquid injectIon field desorptIon IonizatIon (LIFDI) Positive-Ion FT-ICR MS. Ultrahigh mass resolving power (m/Δm50% ≈ 350 000) and high mass accuracy (<500 ppb) facilitate the assignment of a unique elemental compositIon to each peak in the mass spectrum. Thus, each distillate was characterized by mass, heteroatom class, type (number of rings and double bonds), and carbon number distributIon to correlate compositIonal changes with increased boiling point. Negative-Ion ESI FT-ICR MS identifies high relative abundance nonaromatic O2 species that span the entire distillatIon range. All IonizatIon methods re...
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resolutIon and identificatIon of elemental compositIons for more than 3000 crude acids in heavy petroleum by negative Ion microElectrospray high field fourier transform Ion cyclotron resonance mass spectrometry
Energy & Fuels, 2001Co-Authors: Kuangnan Qian, Ryan P. Rodgers, Winston K Robbins, Christine A Hughey, Helen J Cooper, Alan G. MarshallAbstract:Although crude acids are minor constituents in petroleum, they have significant implicatIons for crude oil geochemistry, corrosIon, and commerce. We have previously demonstrated that a single Positive-Ion Electrospray IonizatIon (ESI) high-field Fourier transform Ion cyclotron resonance mass spectrometry (FT-ICR MS) experiment can resolve and identify 3000 chemically different elemental compositIons of bases (basic nitrogen compounds) in a crude oil. Here, we show that negative-Ion ESI high-field FT-ICR MS can selectively Ionize and identify naphthenic acids without interference from the hydrocarbon background. When combined with prechromatographic separatIon, ESI FT-ICR MS reveals an even more detailed acid compositIon. An average mass resolving power, m/Δm50% ≥ 80 000 (Δm50% is mass spectral peak full width at half-maximum peak height) across a wide mass range (200 < m/z < 1000), distinguishes as many as 15 distinct chemical formulas within a 0.26 Da mass window. Collectively, more than 3000 chemically ...
Yahe Zhang - One of the best experts on this subject based on the ideXlab platform.
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characterizatIon of heavy petroleum fractIon by Positive Ion Electrospray IonizatIon ft icr mass spectrometry and collisIon induced dissociatIon bond dissociatIon behavior and aromatic ring architecture of basic nitrogen compounds
Science China-chemistry, 2013Co-Authors: Linzhou Zhang, Yahe Zhang, Suoqi Zhao, Keng H Chung, Quan ShiAbstract:This paper examined the bond dissociatIon behavior and aromatic ring architecture of basic nitrogen compounds in Sudan heavy petroleum fractIon. Both broadband and quadrupole isolatIon modes Positive-Ion Electrospray IonizatIon (ESI) Fourier transform Ion cyclotron resonance mass spectrometry (FT-ICR MS) coupled with collisIon induced dissociatIon (CID) techniques were used to characterize a low sulfur crude oil derived vacuum residuum (VR). The appropriate CID operating conditIon was selected by comparing the molecular weight distributIons of the basic nitrogen compounds under various CID operating conditIons. Both odd- and even-electron fragment Ions were observed from the mass spectrum, indicating that the heterolytic and homolytic bond cleavages occurred simultaneously during the CID process. The odd-electron fragment Ions were predominant in each class species, indicating preferential heterolytic bond cleavages. At the optimal CID conditIon, the alkyl groups decomposed deeply and just left the aromatic cores of the nitrogen compounds. No significant variatIon in double bond equivalent (DBE) value was observed between the fragment and parent Ions, revealing that the dominatIon of single core structure.
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distributIon of sulfides and thiophenic compounds in vgo subfractIons characterized by Positive Ion Electrospray fourier transform Ion cyclotron resonance mass spectrometry
Energy & Fuels, 2011Co-Authors: Peng Liu, Yahe Zhang, Keng H Chung, Quan Shi, Na Pan, Suoqi ZhaoAbstract:Detailed elemental compositIon and distributIon of sulfides and thiophenic compounds in four subfractIons of Kazakhstan vacuum gas oil (VGO) were determined by Positive Ion Electrospray (ESI) Fourier transform Ion cyclotron resonance mass spectrometry (FT-ICR MS). The sulfides in VGO subfractIons were selectively oxidized into sulfoxides using tetrabutylammonium periodate (TBAPI). The sulfur compounds in the oxidized VGO subfractIons were reacted by methylatIon to form methylsulfonium salts and were then characterized. Elemental compositIon and distributIon of sulfides and thiophenic compounds in the VGO subfractIons were characterized by their double bond equivalents (DBE) values and carbon numbers before and after the oxidatIon reactIons. The results showed that the S1 class species with DBE values of 6 and greater are likely thiophenic compounds, while those with DBE values less than 6 are sulfides. As boiling point of VGO increased, the abundance of thiophenic compounds increased. DBE value and carbon...
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molecular characterizatIon of sulfur compounds in venezuela crude oil and its sara fractIons by Electrospray IonizatIon fourier transform Ion cyclotron resonance mass spectrometry
Energy & Fuels, 2010Co-Authors: Keng H Chung, Suoqi Zhao, Yahe Zhang, Chunming XuAbstract:Venezuela crude oil was separated into saturates, aromatics, resins, and asphaltenes (SARA) fractIons. The sulfur compounds in the crude oil and its SARA fractIons were reacted with iodomethane in the presence of silver tetrafluoroborate and converted to methylsulfonium salts. The methylsulfonium salts were characterized by Positive-Ion Electrospray IonizatIon (ESI) and Fourier transform Ion cyclotron resonance mass spectrometry (FT-ICR MS). The S1, S2, S3, O1S1, O1S2, O2S1, and N1S1 class species were identified in crude oil derived methylsulfonium salts. The molecular compositIon and mass distributIon of sulfur compounds in the subfractIons were distinctly different. Small amounts of S1 class species (cyclic-ring sulfides) were present in the saturates fractIon. Thiophenic sulfur compounds were dominant in the aromatics fractIon. Complex multiheteroatoms (N1Sy, OxSy, and N1OxSy class species) were present in the resins and asphaltenes fractIons. The relative abundance plots of double-bond equivalence (D...
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molecular characterizatIon of sulfur compounds in venezuela crude oil and its sara fractIons by Electrospray IonizatIon fourier transform Ion cyclotron resonance mass spectrometry
Energy & Fuels, 2010Co-Authors: Peng Liu, Yahe Zhang, Keng H Chung, Quan Shi, Na Pan, Suoqi ZhaoAbstract:Venezuela crude oil was separated into saturates, aromatics, resins, and asphaltenes (SARA) fractIons. The sulfur compounds in the crude oil and its SARA fractIons were reacted with iodomethane in the presence of silver tetrafluoroborate and converted to methylsulfonium salts. The methylsulfonium salts were characterized by Positive-Ion Electrospray IonizatIon (ESI) and Fourier transform Ion cyclotron resonance mass spectrometry (FT-ICR MS). The S1, S2, S3, O1S1, O1S2, O2S1, and N1S1 class species were identified in crude oil derived methylsulfonium salts. The molecular compositIon and mass distributIon of sulfur compounds in the subfractIons were distinctly different. Small amounts of S1 class species (cyclic-ring sulfides) were present in the saturates fractIon. Thiophenic sulfur compounds were dominant in the aromatics fractIon. Complex multiheteroatoms (N1Sy, OxSy, and N1OxSy class species) were present in the resins and asphaltenes fractIons. The relative abundance plots of double-bond equivalence (D...
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characterizatIon of sulfide compounds in petroleum selective oxidatIon followed by Positive Ion Electrospray fourier transform Ion cyclotron resonance mass spectrometry
Analytical Chemistry, 2010Co-Authors: Chunming Xu, Yahe Zhang, Suoqi Zhao, Keng H ChungAbstract:A novel analytical method for identifying sulfides in petroleum and its fractIons was developed. Sulfides in petroleum were selectively oxidized into sulfoxides using tetrabutylammonium periodate (TBAPI) and identified by Positive-Ion Electrospray IonizatIon (ESI) Fourier transform-Ion cyclotron resonance mass spectrometry (FT-ICR MS). A variety of model sulfur compounds were examined to evaluate the selective oxidizatIon and IonizatIon efficiencies for sulfur compounds in petroleum. Two fractIons, straight-run diesel and saturates of Athabasca oilsands bitumen were investigated using this approach. The oxidizatIon process was highly selective for sulfides from thiophenes and aromatic hydrocarbons. OxidatIon generated sulfoxides were Ionized by Positive-Ion ESI and analyzed by FT-ICR MS. Mass spectra revealed the compositIon characteristics of sulfides in the diesel by contrasting the double bond equivalence (DBE) and carbon number distributIon of sulfur compounds before and after oxidatIon. The abundant ...
Keng H Chung - One of the best experts on this subject based on the ideXlab platform.
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characterizatIon of heavy petroleum fractIon by Positive Ion Electrospray IonizatIon ft icr mass spectrometry and collisIon induced dissociatIon bond dissociatIon behavior and aromatic ring architecture of basic nitrogen compounds
Science China-chemistry, 2013Co-Authors: Linzhou Zhang, Yahe Zhang, Suoqi Zhao, Keng H Chung, Quan ShiAbstract:This paper examined the bond dissociatIon behavior and aromatic ring architecture of basic nitrogen compounds in Sudan heavy petroleum fractIon. Both broadband and quadrupole isolatIon modes Positive-Ion Electrospray IonizatIon (ESI) Fourier transform Ion cyclotron resonance mass spectrometry (FT-ICR MS) coupled with collisIon induced dissociatIon (CID) techniques were used to characterize a low sulfur crude oil derived vacuum residuum (VR). The appropriate CID operating conditIon was selected by comparing the molecular weight distributIons of the basic nitrogen compounds under various CID operating conditIons. Both odd- and even-electron fragment Ions were observed from the mass spectrum, indicating that the heterolytic and homolytic bond cleavages occurred simultaneously during the CID process. The odd-electron fragment Ions were predominant in each class species, indicating preferential heterolytic bond cleavages. At the optimal CID conditIon, the alkyl groups decomposed deeply and just left the aromatic cores of the nitrogen compounds. No significant variatIon in double bond equivalent (DBE) value was observed between the fragment and parent Ions, revealing that the dominatIon of single core structure.
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distributIon of sulfides and thiophenic compounds in vgo subfractIons characterized by Positive Ion Electrospray fourier transform Ion cyclotron resonance mass spectrometry
Energy & Fuels, 2011Co-Authors: Peng Liu, Yahe Zhang, Keng H Chung, Quan Shi, Na Pan, Suoqi ZhaoAbstract:Detailed elemental compositIon and distributIon of sulfides and thiophenic compounds in four subfractIons of Kazakhstan vacuum gas oil (VGO) were determined by Positive Ion Electrospray (ESI) Fourier transform Ion cyclotron resonance mass spectrometry (FT-ICR MS). The sulfides in VGO subfractIons were selectively oxidized into sulfoxides using tetrabutylammonium periodate (TBAPI). The sulfur compounds in the oxidized VGO subfractIons were reacted by methylatIon to form methylsulfonium salts and were then characterized. Elemental compositIon and distributIon of sulfides and thiophenic compounds in the VGO subfractIons were characterized by their double bond equivalents (DBE) values and carbon numbers before and after the oxidatIon reactIons. The results showed that the S1 class species with DBE values of 6 and greater are likely thiophenic compounds, while those with DBE values less than 6 are sulfides. As boiling point of VGO increased, the abundance of thiophenic compounds increased. DBE value and carbon...
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molecular characterizatIon of sulfur compounds in venezuela crude oil and its sara fractIons by Electrospray IonizatIon fourier transform Ion cyclotron resonance mass spectrometry
Energy & Fuels, 2010Co-Authors: Keng H Chung, Suoqi Zhao, Yahe Zhang, Chunming XuAbstract:Venezuela crude oil was separated into saturates, aromatics, resins, and asphaltenes (SARA) fractIons. The sulfur compounds in the crude oil and its SARA fractIons were reacted with iodomethane in the presence of silver tetrafluoroborate and converted to methylsulfonium salts. The methylsulfonium salts were characterized by Positive-Ion Electrospray IonizatIon (ESI) and Fourier transform Ion cyclotron resonance mass spectrometry (FT-ICR MS). The S1, S2, S3, O1S1, O1S2, O2S1, and N1S1 class species were identified in crude oil derived methylsulfonium salts. The molecular compositIon and mass distributIon of sulfur compounds in the subfractIons were distinctly different. Small amounts of S1 class species (cyclic-ring sulfides) were present in the saturates fractIon. Thiophenic sulfur compounds were dominant in the aromatics fractIon. Complex multiheteroatoms (N1Sy, OxSy, and N1OxSy class species) were present in the resins and asphaltenes fractIons. The relative abundance plots of double-bond equivalence (D...
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molecular characterizatIon of sulfur compounds in venezuela crude oil and its sara fractIons by Electrospray IonizatIon fourier transform Ion cyclotron resonance mass spectrometry
Energy & Fuels, 2010Co-Authors: Peng Liu, Yahe Zhang, Keng H Chung, Quan Shi, Na Pan, Suoqi ZhaoAbstract:Venezuela crude oil was separated into saturates, aromatics, resins, and asphaltenes (SARA) fractIons. The sulfur compounds in the crude oil and its SARA fractIons were reacted with iodomethane in the presence of silver tetrafluoroborate and converted to methylsulfonium salts. The methylsulfonium salts were characterized by Positive-Ion Electrospray IonizatIon (ESI) and Fourier transform Ion cyclotron resonance mass spectrometry (FT-ICR MS). The S1, S2, S3, O1S1, O1S2, O2S1, and N1S1 class species were identified in crude oil derived methylsulfonium salts. The molecular compositIon and mass distributIon of sulfur compounds in the subfractIons were distinctly different. Small amounts of S1 class species (cyclic-ring sulfides) were present in the saturates fractIon. Thiophenic sulfur compounds were dominant in the aromatics fractIon. Complex multiheteroatoms (N1Sy, OxSy, and N1OxSy class species) were present in the resins and asphaltenes fractIons. The relative abundance plots of double-bond equivalence (D...
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characterizatIon of sulfide compounds in petroleum selective oxidatIon followed by Positive Ion Electrospray fourier transform Ion cyclotron resonance mass spectrometry
Analytical Chemistry, 2010Co-Authors: Chunming Xu, Yahe Zhang, Suoqi Zhao, Keng H ChungAbstract:A novel analytical method for identifying sulfides in petroleum and its fractIons was developed. Sulfides in petroleum were selectively oxidized into sulfoxides using tetrabutylammonium periodate (TBAPI) and identified by Positive-Ion Electrospray IonizatIon (ESI) Fourier transform-Ion cyclotron resonance mass spectrometry (FT-ICR MS). A variety of model sulfur compounds were examined to evaluate the selective oxidizatIon and IonizatIon efficiencies for sulfur compounds in petroleum. Two fractIons, straight-run diesel and saturates of Athabasca oilsands bitumen were investigated using this approach. The oxidizatIon process was highly selective for sulfides from thiophenes and aromatic hydrocarbons. OxidatIon generated sulfoxides were Ionized by Positive-Ion ESI and analyzed by FT-ICR MS. Mass spectra revealed the compositIon characteristics of sulfides in the diesel by contrasting the double bond equivalence (DBE) and carbon number distributIon of sulfur compounds before and after oxidatIon. The abundant ...