High value utilization of inferior diesel for BTX production: Mechanisms, catalysts, conditions and challenges

Chen, Feng; Zhang, Guohao; Weng, Xiaoyi; Zhang, Yuhao; Zhao, Liang; Cao, Liyuan; Gao, Jinsen; Chen, Xu; Xiangqi, Liu; Gao, Xuhui

doi:10.1016/j.apcata.2021.118095

Cited by 25 publications

(15 citation statements)

References 164 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The untreated VGO (Figure 6a) has an island contour plot with a maximum around the DBE values of 7-13 and a carbon number of 23-31, corresponding to anthracene and pyrenetype structures [40]. The products from VGO hydrocracking (Figure 6b-c) confirm the classical hydrocracking mechanisms [41], and we observe how the heaviest species are first hydrogenated (Figure 6b, lower DBE values at 400 °C). The carbon number is reduced (Figure 6c, at 420 °C) through ring-opening and cracking reactions.…”

Section: P R E P R I N T N O T P E E R R E V I E W E Dmentioning

confidence: 54%

Hydrocracking Mechanisms of Oxygenated Plastics and Vacuum Gasoil Blends

Trueba

Zambrano

Hita

et al. 2023

Preprint

View full text Add to dashboard Cite

Section: P R E P R I N T N O T P E E R R E V I E W E Dmentioning

confidence: 54%

Hydrocracking Mechanisms of Oxygenated Plastics and Vacuum Gasoil Blends

Trueba

Zambrano

Hita

et al. 2023

Preprint

View full text Add to dashboard Cite

“…All catalysts were evaluated in tetralin cracking at 425 °C, 4.0 MPa, and WHSV = 2.0 h –1 . In this system, BTX are regarded as the target products, which are generated via ring-opening, isomerization, and β-scission of tetralin accompanied by C 2 –C 4 species . Other chemicals like C 1 , C 9–10 , and C 11 + are generated as deep cracking products, unconverted intermediates, and coke precursors, respectively .…”

Section: Resultsmentioning

confidence: 99%

“…In this system, BTX are regarded as the target products, which are generated via ring-opening, isomerization, and β-scission of tetralin accompanied by C 2 −C 4 species. 1 Other chemicals like C 1 , C 9−10 , and C 11 + are generated as deep cracking products, unconverted intermediates, and coke precursors, respectively. 4 Typical product distributions at 5.5 h are shown in Table 5.…”

Section: Catalytic Reactions 331 Catalytic Performances In Tetralinmentioning

confidence: 99%

“…Light cycle oil (LCO), as the main byproduct in fluid catalytic cracking processes, is majorly composed of condensed aromatics (>75%), most of which are bi- or tricyclic homologues such as naphthalene, alkylnaphthalene, anthracene, and phenanthrene. − LCO used to be added into diesel oil for viscosity adjustment; however, for diesel upgrading, this demand has witnessed a steep decrease during the last decade owing to its drawbacks like the low cetane number and poor ignition performance. , Meanwhile, light aromatics such as benzene, toluene, and xylene (BTX) are important raw materials in the chemical market, and demand will continue to increase in the future . For example, the worldwide increasing demand in paraxylene (PX) will maintain a growth of 3.5% over the next 5 years as a result of its importance as a major chemical in producing plastics and synthetic fibers. − At the same time, due to the growing demand for downstream products, the growth in demand for BTX is much more than that for refined oil. , The high content of potential aromatics in LCO makes it a possible source for the production of light aromatics.…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Identifying the Location of Real Active Sites in ZSM-5 Zeolites for Tetralin Conversion into Light Aromatics

Guan

Zhang

et al. 2023

Energy Fuels

View full text Add to dashboard Cite

Light cycle oil (LCO) can no longer be used as fuel additives for diesel upgrading, and hence, the catalytic cracking of LCO into light aromatics has become an urgent job for its proper utilization. In this work, toward the rational design of catalysts for LCO cracking, various ZSM-5 zeolites were prepared and utilized in tetralin (as a presentative compound of LCO) cracking to determine the essential locations of active sites. Results show that tetralin could hardly penetrate into the micropores constituted by the 10-member-ring channels of ZSM-5 owing to the large molecular size. Instead, this reaction majorly proceeds via the acid sites residing on the external surfaces rather than those in the intracrystal mesopores. Meanwhile, the external acid sites also possess the advantage of rapid diffusion, which significantly decreases the formation of coke and promotes the catalytic lifetime. Consequently, the morphologies of ZSM-5 play a pivotal role in catalytic performances, among which the nanosized ZSM-5 catalyst was the most outstanding candidate, exhibiting a tetralin conversion of 87.0%, benzene/toluene/xylene total yields of 51.3%, and a lifetime of 22 h as a result of the most abundant external acid sites. These findings disclosed the locations of real active sites in ZSM-5 zeolites in the cracking of tetralin and developed methods to enhance the catalytic performances, which are helpful for the rational design of catalysts for tetralin cracking.

show abstract

“…Hydrocracking is an effective technology to consume diesel, particularly inferior quality diesel, to produce aviation kerosene and chemical raw materials. [1][2][3][4][5] Compared with conventional gas oil hydrocracking, diesel hydrocracking is operated under higher liquid space velocity but lower temperature and hydrogen pressure. Moreover, diesel hydrocracking requires more accurate control over the conversion reactions to achieve the expected product distribution.…”

Section: Introductionmentioning

confidence: 99%