直馏柴油中硫化物甲基锍盐合成及电喷雾-高分辨质谱分析

在四氟硼酸银的催化作用下,以碘甲烷对直馏柴油进行甲基衍生化反应,使其中的有机硫化物转变成极性较强的锍盐,再用电喷雾-傅立叶变换离子回旋共振质谱仪进行检测。结合气相色谱-脉冲火焰光度检测器(GC-PFPD)分析,研究不同类型的硫化物甲基衍生化反应的选择性和转化率。结果表明:柴油中硫化物在室温条件下容易与碘甲烷发生甲基化反应,大部分硫化物转化为锍盐,总转化率超过80%,苯并噻吩类比二苯并噻吩类更易发生甲基衍生化反应,转化率也相应较高。烷基二苯并噻吩不同取代位异构体间反应选择性存在较大差异,高分辨质谱分析结果表明,直馏柴油中存在环状硫醚类化合物。     

柴油馏分中含硫化合物组成与分布特征

采用毛细管气相色谱/脉冲火焰光度检测器(GC/PFPD,Gas Chromatograph/ Pulsed Flame Photometric Detector)对新疆独山子石化公司炼油厂的五种柴油馏分中的硫化物进行了分析。结果表明,常一线馏分中所含的硫化物主要是C0~4苯并噻吩;常二线馏分中除含有C_1~4苯并噻吩外还含有大量的C_0~3二苯并噻吩及部分未知硫化物;焦化柴油中硫化物组成最为复杂,包含中间馏分油中所有常见的硫化物类型;而催化裂化柴油和加氢柴油中硫化物类型主要为烷基苯并噻吩和烷基二苯并噻吩,其中加氢柴油中的硫化物相对丰度比催化裂化柴油低的多。     

全二维气相色谱分析直馏柴油中含硫化合物

采用全二维气相色谱-硫化学发光检测器,以直馏柴油为研究对象,考察了一维色谱柱初始温度、升温速率及两维柱温温差等条件对含硫化合物分离的影响,建立了直馏柴油中含硫化合物的分析方法。本方法对基质复杂的直馏柴油中含硫化合物的分离,并定性分析或归类了直馏柴油中的主要含硫化合物。以苯并噻吩为测试样,以峰面积对浓度作图,硫的浓度在1～100mg/kg范围内,峰面积与硫的浓度呈线性关系,相关系数大于0.999。与传统一维气相色谱相比,全二维气相色谱技术除可检测到苯并噻吩类、二苯并噻吩类等含硫化合物外,还可检测到直馏柴油中的硫醚类化合物;苯并噻吩类和二苯并噻吩类化合物也可得到较好分离。     

气相色谱-原子发射光谱联用技术测定柴油中硫化物

采用气相色谱－原子发射光谱（GC－AED）联用技术对柴油中硫化物进行了定性定量研究，考察了柴油加氢脱硫处理前后硫化物的变化及不同柴油原料硫化物的分布情况。结果表明，1＃柴油可定性出33类硫化物，经加氢脱硫处理后，1－1＃和1－2＃样品硫含量可由1497mg/L分别降到165.1mg/L和90.4mg/L，平均脱除率为89.0%和94.0%。其中噻吩或苯并噻吩的脱除率为100％；C1二苯并噻吩的肿除率为90.0%和96.2%;C2二苯并噻吩的脱除率为80.6%和91.7%；C3二苯并噻吩的脱除率为72.6%和84.4%；C4二苯并噻吩的脱除率为79.0%和90.3%;C5或C6二苯并噻吩的脱除率为58.4%和68.4%；未知硫化物脱除率95.7%和97.9%。噻吩类脱除率视取代基的大小、个数和取代位置的不同脱除率不同；不同原料 总硫和各种硫化物含量差别很大，应根据其硫化物的分布特点，有针对性地研制开发加氢脱硫的催化剂及选择合适的加工工艺。     

哈萨克斯坦及俄罗斯渣油馏分中的硫化物裂解色谱分析

采用裂解气相色谱接脉冲火焰光度检测器（PY-GC-PFPD）,研究了哈萨克斯坦原油及俄罗斯减压原油渣油及其馏分的裂解硫化物的组成分布。依据渣油高温裂解硫化物的主要类型：H2S、噻吩类、苯并噻吩类及二苯并噻吩类,选择噻吩、苯并噻吩（BT）和二苯并噻吩（DBT）模型化合物,考察裂解温度400℃-1000℃及时间5 s-10 s的反应产物及转化率,以证明渣油裂解硫化物基本可反映其在渣油中的结构。采用超临界流体萃取分馏,将俄罗斯和哈萨克斯坦渣油分别分割成18和19个窄馏分,在裂解温度1000℃及10 s条件下,获得了两种渣油及其馏分中H2S、噻吩、BT和DBT的含量分布,推断了渣油中硫化物噻吩类和硫醚类分布规律。     

加拿大合成原油减压馏分油及其催化裂化液体产物中含硫化合物分析

应用GC PFPD和GC MS技术对加拿大油砂合成原油（Synthetic Crude Oil，简称SCO）减压馏分油（350 ℃~500 ℃）中的含硫化合物进行定性定量分析。结果表明，所含硫化物主要是C3~7二苯并噻吩，而催化裂化反应后则以短侧链二苯并噻吩为主，还含少量烷基苯并噻吩和烷基噻吩，三者的质量分数分别为82.04%、13.42%和0.56%，均属于难以加氢脱除的含硫化合物。SCO减压馏分油和大港减压馏分油按不同比例混合后进行催化裂化反应，随着加拿大合成原油减压馏分油搀兑比增加，所得液相产物中烷基噻吩和烷基苯并噻吩质量分数逐渐降低，烷基二苯并噻吩相对质量分数增加，4-MDBT是丰度最高的含硫化合物，显示加氢油的特征。随掺兑比的提高，液相产物中总硫质量分数和柴油馏分中硫质量分数逐渐增高，而汽油馏分中硫质量分数逐渐降低。     

NiY分子筛选择性吸附脱硫性能及作用机理

用液相离子交换法制备了NiY分子筛,并用XRD、TEM、ICP、N2吸附和吡啶吸附原位红外技术等表征手段对其进行了表征. 利用固定床、气相色谱-硫发光检测器（GC-SCD）及傅里叶红外光谱（FT-IR）等方法系统研究了NiY分子筛对噻吩、2-甲基噻吩、3-甲基噻吩、四氢噻吩、苯并噻吩、二苯并噻吩、4-甲基二苯并噻吩、4,6-二甲基二苯并噻吩8种有机硫化物的选择性吸附脱硫性能和吸附机理. 结果表明,NiY分子筛对硫化物的穿透吸附硫容量顺序为四氢噻吩﹥苯并噻吩≈二苯并噻吩≈4,6-二甲基二苯并噻吩﹥4-甲基二苯并噻吩﹥2-甲基噻吩≈3-甲基噻吩﹥噻吩,说明有机硫化物的空间位阻效应不是其在NiY分子筛上吸附的决定因素. 红外结果表明,不同硫化物与NiY分子筛的作用机理并不相同,但主要以硫原子与金属离子配位作用（S-M作用）为主. 噻吩及其烷基取代物在NiY吸附剂上表面酸性作用下发生催化反应,噻吩环的共轭体系遭到破坏形成硫化物大分子或聚合物,导致分子筛孔道的堵塞,严重影响吸附剂的吸附脱硫能力. NiY的选择性吸附脱硫性能是硫化物与吸附中心的作用模式及吸附剂表面酸性综合作用的结果.     

气相色谱法测定催化柴油中硫化物类型分布及数据对比

采用气相色谱-氢火焰离子化检测器-硫化学发光检测器（GC—FID—SCD）联用技术,建立了催化柴油中各种硫化物类型分布的分析方法。考察了色谱条件对催化柴油中各种硫化物分离的影响,定性了某催化柴油中的120多个硫化物,该方法还可以同时提供催化柴油中正构烷烃含量的分布信息。硫化物中的硫在1．5—700mg／L时其峰面积与质量浓度呈较好的线性关系,相关系数达0．9999,响应与硫化物的类型无关。催化柴油中苯并噻吩、4-甲基苯并噻吩、二苯并噻吩、4-甲基二苯并噻吩和4,6-二甲基二苯并噻吩等主要硫化物浓度测定的相对标准偏差（RSD）均小于5．0％。当信噪比（S／N）为3时,测得苯并噻吩硫的检出限为0．1mg／L。将该方法用于不同来源柴油中各种硫化物类型分布的研究,并与气相色谱一原子发射光谱检测器（GC—AED）测硫的数据进行了对比,两种检测器的定量结果大多数具有较好的相关性,相关系数大于0．95。     

重油催化裂化汽油中含硫化合物的分析

 采用气相法 ,分别利用火焰光度检测器 (FPD)和原子发射检测器 (AED)对中国石化北京燕山石油化工公司 (简称燕化 )炼油厂和石家庄炼油厂生产的重油催化裂化 (RFCC)汽油中的硫化物进行了分析。燕化炼油厂RFCC汽油中总硫只有 2 9 5mg/L ,采用FPD无法检测 ;石家庄炼油厂的RFCC汽油中总硫为 72 0 1mg/L。用标样和气相 质谱法 (GC MS)定性 ,FPD分离检测出 19种硫化物 ,主要是硫醇、噻吩类硫化物 ,硫醚类硫化物和二硫化物均未检出。用AED鉴定出燕化炼油厂RFCC汽油中的硫化物 12种 ,主要是噻吩和四氢噻吩类、低碳硫醇和二硫化物。     

催化柴油中硫化物的气相-原子发射光谱分析方法及应用

 建立了催化柴油馏分中各种硫化物类型分布的气相 原子发射光谱分析方法,考察了条件对各种硫化物分离的影响,定性(或归类)了催化柴油中的130多个硫化物,计算了程序升温条件下各种硫化物的保留指数,为不同实验室的定性比较和方法的转让提供了依据。硫化物中的硫在2mg/L～1000mg/L时其质量浓度与峰面积呈较好的线性关系,相关系数达0 997。几种硫化物(苯并噻吩、4 甲基苯并噻吩、二苯并噻吩、4 甲基二苯并噻吩、4,6 二甲基二苯并噻吩)6次测定所得峰面积的相对标准偏差均小于5 0%。当信噪比(S/N)为3时,测得苯并噻吩硫的检出限为0 1mg/L。     

Electronic absorption and resonance Raman spectra of large linear carbon clusters isolated in solid argon

Neutral and anionic carbon clusters have been generated via a laser-induced graphite-based plasma and deposited in a solid argon matrix. Anionic clusters were formed from neutral clusters by using crossed electron/carbon cluster beams. Thermal annealing (to 36 K) resulted in the aggregation of the smaller carbon species, leading to the formation of long chain neutral and anionic clusters. Spectroscopic measurements in the ultraviolet, visible, near-infrared and infrared regions revealed a series of bands attributable to a homologous set of odd-numbered C5-C29 neutral clusters and even-numbered C6(-)-C36- anionic clusters. Good agreement is found for the band positions of carbon chains containing odd C15-C21 neutrals and even C6(-)-C22- anions, with species previously identified by Maier and coworkers using mass selection or laser vaporization, followed by neon matrix isolation. Resonance Raman frequencies for the neutral C17, C21 and C23 species are shown to be consistent with the above attributions. Density functional theory calculations agree well with the observed bands. It is found that certain low frequency Raman stretching frequencies decrease in a predictable way with increasing chain length. Comparison of the 0(0)0 absorption transitions of the even C18(-)-C36- anionic clusters with the 'unidentified' infrared (UIR) interstellar emission bands suggests that the electronic emission from specific long chain carbon anions may contribute to the some of the UIR bands.     

Identification and quantification of lipids from rabbit Harderian glands by gas chromatography/mass spectrometry

Lipids from hydrolysed extracts of Harderian glands from the rabbit were examined as trimethylsilyl, acetonide, nicotinate and picolinyl esters and shown to consist mainly of acylated glycerol ethers and acylated hydroxy-glycerol ethers. Constituents amounting to 98.8% of the recovered secretion were identified. Fatty acids were mainly normal, saturated compounds with chain lengths from 12 to 24 carbon atoms; n-16:0 and n-18:0 accounted for about 40% of the identified acids. Small concentrations of iso-17:0 and unsaturated acids with 18-carbon chains were also identified. Fatty alcohols were again mainly normal-unsaturated compounds; the chains varied from C18 to C25 with 20:0-OH and 22:0-OH being the most abundant. Three types of 1-alkyl glycerols were found. The major constituents had normal, saturated chains with from 14 to 23 carbon atoms with the even carbon chains predominating. These were accompanied by hydroxylated derivatives of the 16- and 18-carbon glycerol ethers with hydroxy groups in the 10, 11 and 12 positions. Branched-chain glycerol ethers were of low concentration and contained predominantly iso chains. Many of these compounds have not been reported before in this secretion. Low concentrations of the previously reported hydroxy acids with n-C14, -C15 and -C16 chains were also found. Nicotinate derivatives were applied to the structural determination of glycerol ethers for the first time and shown to reveal the position of methyl branch points in an analogous manner to that previously shown for mono- and di-hydric alcohols. Acids were identified as picolinyl esters.     

工业混合烷中含硫化合物的鉴定

建立了一种工业混合烷中含硫化合物的新的定性鉴定方法。样品经过氢氧化钾和硝酸银预处理后,可将工业混合烷中含硫化合物的硫醇、硫醚和噻吩进行分离,而后用GC-MS测定,鉴定了工业混合烷中30种硫醚和5种硫醇化合物。     

A comparison of results obtained using liquid injection and headspace solid-phase microextraction for crude oil analysis by GC with mass spectrometer detection

Gas chromatographic (GC) analysis in solution and head space solid-phase microextraction (SPME)-GC analysis of a sample of crude oil gave different results. The SPME technique allowed the identification of a larger number of components than by using usual GC-mass spectrometry (MS). The method failed within the range of C14-C25 where GC-MS in solution allowed to obtain more representative results; on the contrary, SPME allowed to obtain data on the presence of volatile compounds that can not be identified in GC-MS analysis in solution. Furthermore, in the range C8-C12, SPME allowed to identify approximately 30 compounds not shown in the GC-MS analysis in solution. SPME analysis showed the presence of some alkenes not identified in GC-MS analysis in solution. SPME-GC-MS can be used in the analysis of crude oil in contaminated soil.     

Investigation of the thermal transformations of acrylonitrile copolymers with methylthiirane in dilute solution in dimethylformamide

The effect of introduction of the comonomer methylthiirane (MT) into the main chain of polyacrylonitrile (PAN) on the thermal transformations of the macromolecules in dilute DMF solution was studied. For this purpose, statistical copolymers of acrylonitrile and MT were synthetized and their pyrolysis in solution was investigated. It was found that introduction of the thioether group into the main chain of PAN results in essential changes in the thermal behaviour of the copolymers as compared to the homopolymer. The results of rheological, thermal and spectral studies on the solutions suggest that the direction of the thermochemical reaction changes on introduction of the thioether group into the PAN molecule. In such copolymers the reaction will preferably proceed by the -C≡N groups forming conjugated cyclic structures.     

醇类改性剂对胶束电动色谱分离的影响

胶束电动色谱（ＭＥＫＣ）是毛细管电泳常用的一种分离模式,它能使电中性化合物得到高效的分离．ＭＥＫＣ的分离度可通过调节电解质溶液的组成来提高．其中,有机改性剂的使用是近几年来ＭＥＫＣ研究的重点之一［１,２］．已有文献［３～５］报道以醇类作为电解质溶液的...     

Gas-phase interaction of thiophene with the Ti(8)C(12)(+) and Ti(8)C(12) met-car clusters

The reactivity of the Ti(8)C(12)(+) met-car cation toward thiophene was investigated using density functional theory (DFT) and mass selective ion chemistry. It is shown that the experimentally observed mass spectrum can be well described by the DFT calculations. In contrast to the weak bonding interactions seen for thiophene on a TiC(001) surface, the Ti(8)C(12)(+) met-car cation is able to interact strongly with up to four thiophene molecules with the cluster staying intact. In the most stable conformation, the thiophene molecules bond to the four low-coordinated Ti(0) sites of Ti(8)C(12)(+) via a eta(5)-C,S coordination. The stability and the activity of the Ti(8)C(12)(+) met-car is observed to increase with an increasing number of attached thiophene molecules at the Ti(0) sites, which is associated with a significant transfer of electron density from thiophene to the cluster. The additional electron density on the Ti(8)C(12)(+) cation cluster, however, is not sufficient to cleave the C-S bonds of thiophene and the dissociation reaction of thiophene is predicted to be a highly activated process. By contrast, DFT calculations for the neutral Ti(8)C(12) met-car predict that the dissociation reaction leading to adsorbed S and C(4)H(4) fragments is energetically favorable for the first thiophene molecule. The binding behavior for subsequent addition of thiophene molecules to the neutral met-car is also presented and compared to that of the cation.     

Equivalent chain lengths of all C4-C23 saturated monomethyl branched fatty acid methyl esters on methylsilicone OV-1 stationary phase

Isomer mixtures of monomethyl branched saturated C7-C23 fatty acid methyl esters (FAME) were prepared by performing a methylene insertion reaction to the straight chain FAME and this study model was completed by using commercially available standards of C4-C7 FAME. The equivalent chain lengths (ECL) of all 220 C4-C23 monomethyl branched FAME on OV-1 stationary phase were measured, achieving an average repeatability of ±0.0004 ECL units. The monomethyl branched FAME was identified by GC on the basis of regularity of the fractional chain lengths (FCL) dependence on the number of carbon atoms (C(z)) of individual homologous series of methyl 2-, 3-, …, 21-FAME. The prediction of retention of the first homologues, having the new position of methyl group beginning at higher carbon atoms number, and analogously for the second, third, fourth, and other members of the homologous series, allowed the dependence FCL=f(C(z)) for the first and subsequent members of beginning homologous of monomethyl derivatives of FAME. The identification was confirmed by mass spectrometry. All of the methyl isomers of FAME, which could not be completely separated by gas chromatography due to having a methyl group in surroundings of the middle of the carbon chain, were resolved by mass spectrometry using deconvolution in a SIM-mode. Measured gas chromatographic and mass spectrometric data were applied for identification of the monomethyl branched saturated FAME in tongue coating.     

Facile Synthesis of Al-pillared Mesoporous Montmorillonite Assisted with Concentrated Al13 Solution

Al-pillared mesoporous montmorillonite was facilely synthesized from concentrated Al13 solution obtained by vacuum concentrating-ultrasonic pillaring strategy.Concentrated Al13 solution could reduce the process of pillare and increase pillaring efficiency.The absolute value of layer distance could be increased by 0.96 nm via concentrated Al13 solution pillare.27Al NMR indicates that Al Keggin ions of concentrated Al13 are arranged in a more regular way by vacuum concentrating method.The Al-pillared mesoporous montmorillonite from concentrated Al13 solution has bigger specific surface area and even pore size distribution which were characterized by X-ray diffraction（XRD） and nitrogen adsorption measurement.Furthermore the catalytic activity of Ai-pillared montmorillonite loaded Ni and Mo catalysts was tested by the hydrodesulfurization of thiophene.The thiophene conversion reached 77.5％,which was higher than the corresponding value reported in the literature.