直留ナフサおよびfccガソリン中の硫黄化合物の分析

Abstract

Sulfur-containing compounds in straight-run naphtha and catalytic-cracked gasoline were analyzed quantitatively using gas chromatography with a sulfur chemiluminescence detector. Pretreatment of the samples by open column chromatography and silver nitrate treatment were introduced to assign sulfur species. Commercial reagents, prepared standard samples and a commercial mass spectrum library were also utilized to assign the sulfur species. The sulfur content of naphtha was 242 ppm and 83 compounds were identified. Sulfur species consisted of 34 wt％ of thiacycloalkanes, 38 wt％ of thiols and sulfides, 12 wt％ of thiophenes, 11 wt％ of disulfides, and 5 wt％ of unknown compounds. The sulfur content of gasoline was 154 ppm and 41 compounds were assigned. Sulfur species consisted of 46 wt％ of thiophenes, 32 wt％ of benzothiophenes, 14 wt％ of thiols and sulfides, 4 wt％ of thiacycloalkanes, 0.6 wt％ of disulfides, 0.3 wt％ of hydrogen sulfide and 3 wt％ of unknown compounds. The combination of two types of pretreatment methods was effective for quantitative analysis of sulfur compounds contained in the distillate. The results of hydrodesulfurization of light distillate suggested that difficulty of hydrodesulfurization could be predicted from the composition of sulfur compounds in the distillates.

Sulfur-Doped g-C3N4-Supported Ni Species with a Wide Temperature Window for Acetylene Semihydrogenation

“…However, from another perspective, the catalyst of Ni/ g-C 3 N 4 -T may be a potential sulfur-resistant material; after all, naphtha and its derived ethylene feeds generally consist of several hundred ppm of sulfide. 28 Another important issue is oligomerization. In fact, oligomerization and its corresponding oligomers are extremely complex, due to considerable species from C 3 to C 32 and from gas-phase to liquid-phase to solid-phase oligomers, including alkenes, dienes, and alkanes with series of isomers.…”

“…This is a problem to be solved. However, from another perspective, the catalyst of Ni/g-C 3 N 4 -T may be a potential sulfur-resistant material; after all, naphtha and its derived ethylene feeds generally consist of several hundred ppm of sulfide …”

Coking Resistance of Specialized Coil Materials during Steam Cracking of Sulfur-Free Naphtha

“…Straight run naphthas have sulfur concentrations usually ranging from 20 to 100 ppmw, 2,11 although values as high as 250 ppmw can be reached. 62,63 It is thus obvious that the observations made for coking during ethane cracking cannot be simply translated to naphtha cracking. Hence, there is a clear need to study coke formation under naphtha cracking conditions on several alloys to determine if the material has an impact on coke formation during naphtha cracking as significant as during ethane cracking.…”

“…For example, it has been reported that unsaturated and aromatic hydrocarbons have the highest coking tendency. , Therefore, typically a distinction is made between coking models developed for gaseous feeds , and liquid feeds. ,,, An additional complexity is the presence or addition of sulfur to the feed because this element typically increases coke formation, − although it also causes a significant reduction of CO in the effluent stream. Straight run naphthas have sulfur concentrations usually ranging from 20 to 100 ppmw, , although values as high as 250 ppmw can be reached. , It is thus obvious that the observations made for coking during ethane cracking cannot be simply translated to naphtha cracking. Hence, there is a clear need to study coke formation under naphtha cracking conditions on several alloys to determine if the material has an impact on coke formation during naphtha cracking as significant as during ethane cracking.…”