2719-63-3Relevant articles and documents
Effect of surface silicon modification of H-beta zeolites for alkylation of benzene with 1-dodecene
Han, Minghan,Li, Ruimin,Xing, Shiyong,Zhang, Shuai
, p. 10006 - 10016 (2020/03/23)
H-beta zeolites of 100-200 nm (named BEA-L) and 20-30 nm (named BEA-S) were treated by chemical liquid deposition (CLD) of tetraethyl orthosilicate (TEOS) to improve the selectivity of 2-phenyl linear alkylbenzene (2-LAB) from benzene alkylation with 1-dodecene. The results indicate that H-beta zeolite with a smaller crystal size has a longer lifetime due to shorter channels and less diffusion limitation. The deposited SiO2 layers passivated the external surface acid sites of the zeolite and made the pores narrower. BEA-L lost more external Br?nsted acid sites than BEA-S with the same added amount of TEOS, which was due to the severe aggregation of BEA-S grains. This increased passivation gave BEA-L increased 2-LAB selectivity. And when the added amount of SiO2 was 7.20 wt% of the parent zeolite, the selectivity of 2-LAB over BEA-L significantly increased from 41.9% to 54.7% while that of BEA-S only increased by 2%.
A process for preparing long-chain alkyl benzene (by machine translation)
-
Paragraph 0080-0088; 0098-0101, (2019/05/16)
The invention discloses a process for preparing long-chain alkyl benzene, including: the [...] chain alkyl agent in the metal compound assistants and the presence of the ionic liquid catalyst for carrying out the alkylation reaction, containing the reaction product of the long-chain alkyl benzene; wherein the alkylating agent is C states the long chain10 - C18 Straight-chain olefin or halide; said ionic liquid catalyst comprises a cation and anion, the cation is selected from the isoquinoline kind of positive ion, quinoline kind of positive ion and benzimidazole in at least one of the kind of positive ion, the anion is selected from sulfuric acid hydrogen radical, trifluoromethanesulfonic acid radical, the dihydrogen phosphates, paratoluene sulfonic acid, trifluoroacetic acid radical, four fluorophosphoric acid radical and six fluoboric acid in the root of the at least one. The method of the invention the kind of positive ion cation is isoquinoline, quinoline kind of positive ion or benzimidazole kind of positive ion of the ionic liquid as catalyst, to mix with the additive for preparing long-chain alkylbenzene, mild reaction conditions, the reaction conversion rate of raw materials is high, the product has good choice. (by machine translation)
Selective synthesis of linear alkylbenzene by alkylation of benzene with 1-dodecene over desilicated zeolites
Aslam, Waqas,Siddiqui, M. Abdul Bari,Rabindran Jermy,Aitani, Abdullah,?ejka, Ji?í,Al-Khattaf, Sulaiman
, p. 187 - 197 (2014/03/21)
The alkylation of benzene with 1-dodecene to linear alkylbenzenes (LAB) was investigated over 12-ring zeolites MOR, BEA, and FAU with varying framework topologies and Si/Al ratios. The reaction was carried out under a high-pressure, 20 bar, in a fixed-bed flow reactor at 140 C, using WHSV 4 h-1, benzene/1-dodecene molar ratio of 6.0 and time-on-stream of 6.0 h. In contrast to MOR and BEA zeolites, FAU exhibited the lowest selectivity (24%) to the desired 2-phenyl dodecane (2-LAB) due to its large cavities. The MOR and BEA with different Si/Al ratios were further desilicated using alkali-metal treatments (0.2 M and 0.05 M NaOH) to create hierarchical porous structure. The desilication of both zeolites improved the conversion of 1-dodecene and the selectivity to 2-LAB. The excellent stability resulting from desilication is attributed to a better diffusivity of the LAB isomers, shortening of real contact time, due to the enhanced mesporous structure in both zeolites and the higher Lewis acidity. The selectivity to 2-LAB increased to 70% over desilicated MOR (Si/Al ratio = 20) compared with a selectivity of 35% over desilicated BEA (Si/Al ratio = 24).
