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221.
《Journal of separation science》2017,40(7):1508-1515
Benzene, toluene, ethylbenzene, and xylenes are some of the most hazardous constituents found in commercial gasoline samples; therefore, these components must be monitored to avoid toxicological problems. We propose a new routine method of ultrafast gas chromatography coupled to flame ionization detection for the direct determination of benzene, toluene, ethylbenzene, and xylenes in commercial gasoline. This method is based on external standard calibration to quantify each compound, including the validation step of the study of linearity, detection and quantification limits, precision, and accuracy. The time of analysis was less than 3.2 min, with quantitative statements regarding the separation and quantification of all compounds in commercial gasoline samples. Ultrafast gas chromatography is a promising alternative method to official analytical techniques. Government laboratories could consider using this method for quality control. 相似文献
222.
Grasielli C. de Oliveira Priscila O. Vicentino Ricardo J. Cassella Yutao T. Xing Eduardo A. Ponzio 《Electroanalysis》2021,33(3):682-694
A composite electrode based on acrylonitrile-butadiene-styrene and graphite chemically modified with a bismuth film (AGCE-BiF) was applied for the simultaneous determination of Cd2+ and Pb2+ in gasoline samples. Extraction induced by microemulsion breaking (EIMB) was used for the first time in the preparation of the samples for electroanalysis. AGCE-BiF was characterized by SEM, AFM, CV, and SWASV. The sensor showed an increase in sensitivity via in situ modification with bismuth film. The LOD was 4 μg L−1 for Cd2+ and 2 μg L−1 for Pb2+. The results showed satisfactory recoveries and precision, being statistically compatible to those obtained with FAAS. 相似文献
223.
通过对异辛烷、汽油和甲缩醛的红外谱图进行分析,确定了1 145 cm–1处吸收峰作为甲缩醛的红外定量谱带。基于朗伯–比耳定律,分别采用0.1,0.2,0.5 mm光程池,对系列浓度标准溶液进行吸光度的测定,建立校准曲线,适合定量的溶液浓度范围分别为0.2~4.2,0.1~2.2,0.1~0.9 g/L;线性方程分别为Y=0.070X+0.001,Y=0.136X+0.001,Y=0.322X+0.002;相关系数分别为0.999 5,0.999 8,0.999 7。质量浓度在0.1~2.2 g/L之间的试样溶液应优先采用0.2mm光程池,测定结果的相对误差小于5%,重复性相对标准偏差小于2.0%(n=6)。 相似文献
224.
Xiangxue Zhu Yuzhong Wang Xiujie Li Hongbing Li Peng Zeng Jie An Fucun Chen Sujuan Xie Hongping Lan Dawei Wang Shenglin Liu Longya Xu 《Journal of Energy Chemistry》2013,22(5):755-760
The aromatization of light alkenes in liquefied petroleum gas (LPG) with and without dimethyl ether (DME) addition in the feed was investigated on a modified ZSM-5 catalyst. The results showed that under the given reaction conditions the selectivity of alkenes to high-octane gasoline blending components was markedly enhanced and the formation of propane and butanes was greatly suppressed with the addition of DME. It was also found that the distribution of C5+ components was changed a lot with DME addition into the LPG feed. The formation of branched hydrocarbons (mainly C6?C8 i-paraffin) and multi-methyl substituted aromatics, which are high octane number gasoline blending components, was promoted significantly, while the content of n-paraffins and olefins in C5+ components was decreased obviously, indicating that in addition to the oligomerization, cracking, hydrogen-transfer and dehydrogenation-cyclization of alkenes, the methylation of the formed aromatics and olefins intermediates also plays an important role in determining the product distribution due to the high reactivity of surface methoxy groups formed by DME. And this process, in combination with the syngas-to-methanol/DME technology, provides an alternative way to the production of high-octane gasoline from coal, natural gas or renewable raw materials. 相似文献
225.
With the development of automotive industry, the consumption of fuels has been steadily on the increase. The emission of tail gas becomes greater and greater, and the air pollution has been increasingly serious[1,2]. 相似文献
226.
Attila Pintér Antal Tungler Lajos Nagy László Vida László Sebestyén Tivadar Gál József Kohán János Kerezsi 《Reaction Kinetics and Catalysis Letters》2006,88(1):175-181
Summary Steam cracking of several gasoline and gas oil samples was carried out under different conditions and the results are reported.
Some of sample feedstocks were previously cracked in a commercial plant so the laboratory and commercial results could be
compared. It was found that the laboratory reactor was more sensitive to the changes of the composition of the raw materials. 相似文献
227.
228.
硅胶表面苯并噻吩分子印迹聚合物的分子识别与吸附性能 总被引:2,自引:0,他引:2
选用γ-氨丙基三乙氧基硅烷和α-甲基丙烯酸修饰的硅胶作为载体,以甲基丙烯酸为功能单体,二甲基丙烯酸乙二醇酯为交联剂,苯并噻吩为模板分子,合成一种具有选择性识别苯并噻吩分子的印迹聚合物。采用红外光谱、元素分析及N2吸附对其结构进行了表征,以模拟汽油通过静态吸附对其吸附性能进行了研究。结果表明,在硅胶载体表面成功地嫁接了多孔的分子印迹聚合物薄层。印迹聚合物对苯并噻吩具有良好的识别性能,对苯并噻吩的吸附动力学满足Langergren准一级反应动力学方程,吸附过程属于单分子层吸附。符合Langmuir吸附模型印迹聚合物对苯并噻吩的平衡吸附容量达57.4×10-3,而非印迹聚合物的吸附容量为33.1×10-3。印迹聚合物在经过多次再生后其吸附容量基本不变,从而为在汽油深度脱硫中有效脱除噻吩类硫化物提供了一种新技术途径。 相似文献
229.
本文首先介绍了国外以玉米、废弃生物质为原料发展生物炼油厂的设想;然后根据我国国情和已有技术基础,设想了以甜高梁、木薯为原料生产乙醇车用汽油和化工产品的生物炼油厂,以及以菜籽油、棉籽油为原料生产生物柴油和化工产品的生物炼油厂;最后探讨了遇到的问题和采取的对策。 相似文献
230.
Catalytic cracking of C5+ gasoline over hy zeolite 总被引:1,自引:0,他引:1
Marcelo J. B. Souza Antonio O. S. Silva Valter J. Fernandes Jr Antonio S. Araujo 《Reaction Kinetics and Catalysis Letters》2003,79(2):257-262
The catalytic conversion of a C5+ natural gasoline over the HY zeolite has been studied. The results show the formation of
C2, C3 and C4 hydrocarbons with an apparent activation energy of ca. 39 kJ mol-1.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献