TENSIDE SURFACTANTS DETERGENTS
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2023
·Vol. 60
·期 4
·368-375
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IF 1
Yarou Yang,Xu Li,Jinxiang Dong
Benzene and 1-dodecene are often alkylated to produce linear alkylbenzene (LAB). LAB is the raw material for the production of linear alkylbenzene sulfonate (LAS), a very important anionic surfactant used in both industrial cleaning and commercial laundry processes, as well as in household laundry detergents. In the present study, we investigated the use of [Et 3 NH]Cl–2AlCl 3 modified with CuCl 2 as a catalyst for the alkylation of benzene with 1-dodecene, specifically looking at the effect of reaction conditions on product activity. The results showed that a conversion of 1-dodecene of 100.0 % and a selectivity of LAB of 93.79 % could be obtained when the following ideal reaction conditions were present: molar ratio of benzene/1-dodecene = 6, reaction temperature = 25 °C, reaction time = 10 min, stirring speed of 1000 rpm and addition of 5.0 mol % CuCl 2 ). The catalyst concentration was 7.0 mol %. FTIR and 31 P-TMPO-NMR measurements were performed to characterise the ionic liquid before and after the addition of CuCl 2 . After the addition of CuCl 2 , it was found that the acidity of the ionic liquid had decreased. The regeneration of the catalyst was also investigated and the cause of inactivation of the catalyst was determined. The results showed that CuCl 2 modified the ionic liquids and decreased the benzene/1-dodecene ratio, but the high product selectivity was maintained.
研究领域:
化学工程
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催化剂科学
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DOI
高影响因子
APPLIED CATALYSIS A-GENERAL
·
2025
·
IF 4.8
Lu Cheng,Xingtao Ren,Shiyao Lu,Dameng Gao,Jing Yue
Regulating the hydroformylation capacity of heterogeneous catalysts is essential for efficiently converting higher olefins into aldehydes. In this study, a magnetic single-atom rhodium-cobalt-based catalyst (RhCo SACs) was synthesised by modifying Fe 3 O 4 with polymerised carbon nitride. Maintaining a constant metal single-atom loading, the catalytic activity in 1-dodecene hydroformylation was modulated by adjusting the type of N species in the support. The distribution of single atoms and valence states was characterised. At the same time, density functional theory (DFT) calculations were conducted to evaluate substrate binding energies and reaction-free energy barriers, providing insights into reaction mechanisms and pathways. The RhCo-pyridinic N configuration lowered the Gibbs free energy of the rate-determining and hydrogenation steps, enhancing substrate reaction activity. Compared to RhCo-graphitic N, RhCo-pyridinic N demonstrated superior performance, achieving a 1-dodecene conversion rate of 98.3% and aldehyde selectivity of 98.6%. Furthermore, the catalyst was magnetically recovered without loss of activity or mass and maintained stable performance over 10 reuse cycles. These findings present a novel and efficient strategy for the precise design of magnetic single-atom catalysts with potential practical applications in the hydroformylation of high-carbon olefins.
研究领域:
催化化学
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材料科学
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理论计算化学
✓ 已验证
产品关联
DOI
高影响因子
CHINESE JOURNAL OF CHEMICAL ENGINEERING
·
2022
·
IF 3.898
Shiyong Xing,Yan Cui,Tiefeng Wang,Jinwei He,Minghan Han
In the present work, the effect of oxides on the alkylation of benzene with 1-dodecene was comprehensively investigated over MCM-49 n -heptanol, n -heptaldehyde and n -heptanoic acid were selected as the model oxides herein, and obvious decrease of lifetime could be caused by only trace amount of oxides added in the feedstocks. However, the deactivated catalysts were difficult to be regenerated by extraction with hot benzene. Additionally, coke-burning was also proved to be incapable to regenerate the deactivated catalysts mainly for the dealumination during calcination . Further characterizations complementary with DFT calculations were conducted to demonstrate that the deactivation was mainly due to the firm adsorption of oxides on the acid sites.
研究领域:
化学工程
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催化科学
✓ 已验证
产品关联
DOI
高影响因子
RSC Advances
·
2015
·Vol. 5
·期 76
·62241-62247
·
IF 3.84
Yibo He,Chao Wan,Qinghua Zhang,Xiaoli Zhan,Dang-guo Cheng,Fengqiu Chen
Friedel–Crafts alkylation of benzene with 1-dodecene, which is an important reaction of synthetic detergent, was studied using the catalyst [bmim][TFSI]/AlCl3 (1-butyl-3-methylimidazolium bis((trifluoromethyl)sulfonyl)imide/AlCl3). These ionic liquid catalysts show biphasic behaviors at a specific condition. Active site species and Lewis acidity were determined by NMR and acetonitrile probe FT-IR. NMR spectroscopy investigations indicated that “coordinated” and “uncoordinated” [TFSI]− existed in the ionic liquid catalyst system simultaneously, while tetrahedral 4-coordinate Al2Cl7− was the main active species for Friedel–Crafts alkylation. The complex [AlClx(TFSI)y]− tends to decompose and release 4-coordinated Al2Cl7− and [TFSI]−. The phase behavior study of the ionic liquid [bmim][TFSI]/AlCl3 demonstrated that the upper phase could be used as an efficient heterogeneous catalyst when AlCl3/IL ≥ 1.5. Due to the presence of the anion [TFSI]− around the active sites, especially [TFSI]− at the “uncoordinated” state, the ionic liquid formed a stable and hydrophobic chemical environment, which enhanced catalyst durability. The influence of various reaction conditions including catalyst reusability on the alkylation reaction was studied, and the potential reasons for catalyst deactivation were discussed. The highest 2-LAB selectivity was more than 50% when 1-dodecene conversion was nearly 100%. Compared with liquid or solid acid catalyst, ionic liquid catalysts have many advantages concerning energy and the environment.
研究领域:
化学工程
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催化化学
✓ 已验证
产品关联
DOI
高影响因子
CATALYSIS TODAY
·
2016
·
IF 4.312
Yibo He,Qinghua Zhang,Xiaoli Zhan,Dang-guo Cheng,Fengqiu Chen
Friedel–Crafts alkylation of benzene with 1-dodecene, which is an important reaction of synthetic detergent, was studied via ionic liquid [bmim][TFSI]/AlCl 3 (1-butyl-3-methylimidazolium bis((trifluoromethyl)sulfonyl)imide/AlCl 3 ) immobilized on SBA-15 catalysts. XRD, BET, TEM, TG, ammonia TPD investigations were used to search insight into catalyst characteristic. The immobilized catalysts preserved ordered structure and presented high specific surface areas. The utilization of active sites was significantly improved by immobilization. Based on ammonia TPD, immobilized catalysts exhibited higher Lewis acidity than aluminum chloride grafted SBA-15. TG indicated that thermal stability of ionic liquid has been improved by immobilization. The influences of various reaction conditions including reaction time, benzene/1-dodecene ratio were studied. Immobilized ionic liquids have better performance of no matter 1-dodecene conversion or 2-linear alkyl benzene (2-LAB) selectivity, than bulk ionic liquid catalysts or aluminum chloride grafted mesoporous materials. 2-LAB selectivity can be increased from about 35% with bulk ionic liquid to more than 60% with immobilized catalysts. Under optimal condition, 2-LAB selectivity reached as high as 80%. The immobilized catalysts could be reused. And at 3th cycle of catalysts, 1-dodecene conversion could still reach more than 50%. The role of deactivation was proposed based on TEM, BET and TG investigations. By-products as oligomer , produced by oligomerization of olefin , blocked or covered the pores, led to deactivation of catalysts.
研究领域:
化学工程
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催化材料科学
✓ 已验证
产品关联
DOI
高影响因子
INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
·
2021
·
IF 3.764
Weijian Lu,Jianwen Zhang,Shiqi Zhang,Chen Ji,Ying Wu,Huiyong Chen,Yanxiong Fang,Jinxiang Dong,Baoyu Liu
The development of zeolite catalysts for linear alkylbenzene production is of crucial importance in achieving green chemical processes for the detergent industry. In the present research, the fabricated beta zeolite catalysts exhibited extraordinary activity (73%) and selectivity of 2-LAB (85%) in the alkylation of benzene with 1-dodecene, which benefited from the open micropore-to-mesopore networks, exposed acid sites, and shape-selectivity of special topology of beta zeolites. The computer calculations revealed that both benzene and 1-dodecene can enter into the 12-MR channels of beta zeolites, in which 1-dodecene was adsorbed on the surface of 12-MR channels in the form of chemical adsorption, and the fixed 1-dodecene was attached to benzene combined with the matched pore size of 12-MR channels of beta zeolites to effectively produce the desired 2-LAB. Moreover, the mesopore beta zeolites also presented superior stability compared with traditional micropore beta zeolite in the alkylation between benzene and 1-dodecene due to enhanced diffusion. Our work definitely paved a way to develop mesopore beta zeolites as a new type of highly efficient heterogeneous catalysts for industrial production of 2-LAB.
研究领域:
化学工程
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催化
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材料科学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF LIQUID CHROMATOGRAPHY & RELATED TECHNOLOGIES
·
2015
·
IF 0.606
Haiyan Liu,Yamin Ma,Fengqing Wang,Jiafei Wang,Quanjie Liu
A new poly(1-dodecene-co-trimethylol propane triacrylate-co-ethylene dimethacrylate) [poly(C12-co-TMPTA-co-EDMA)] monolithic column was prepared via in situ free-radical polymerization reaction. Various parameters affecting the polymerization were investigated and optimized. The permeability of the monolithic column was calculated as 2.9098 × 10−14 m2 with methanol as the mobile phase and the surface areas was 73.1 m2/g by the nitrogen adsorption–desorption experiment. The morphologies of the monolith were characterized by scanning electron microscopy (SEM) and the mechanical strength has been studied in detail as well. The prepared monolith was then used as the stationary phase of reversed phase high-performance liquid chromatography (RP-HPLC) to separate small molecule compounds. Column efficiency for chlorobenzene reached 14,340 theoretical plates per meter. The monolith also showed satisfactory reproducibility, based on the retention times of benzene, phenol, chlorobenzene, diphenylamine, and anthracene; the relative standard deviation (RSD) values for run-to-run, column-to-column and batch-to-batch were less than 0.62%, 3.2%, and 5.7%, respectively.
研究领域:
分析化学
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材料科学
✓ 已验证
DOI
高影响因子
RSC Advances
·
2020
·Vol. 10
·期 17
·10006-10016
·
IF 3.119
Ruimin Li,Shiyong Xing,Shuai Zhang,Minghan Han
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 Brønsted 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%.
研究领域:
催化
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化工
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材料科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
·
2017
·
IF 3.133
Yan-xia Wang,Feng Li,Feng Wang,Yan-feng Pu,Ning Zhao,Fu-kui Xiao
The effects of the polymerization conditions on the yield of insoluble sulfur were investigated by using olefin, such as the 1,-dodecene, 1,-tetradecene, 1,-octadecene as well as acids, such as the salicylic acid, lauric acid and the oleic acid as polymerization stabilizers . The properties of the as-prepared insoluble sulfur were characterized by mu-Raman spectrometer and differential scanning calorimetry (DSC). The results demonstrated that both the olefin and acid stabilizers could couple with the end groups of the IS, thus improved the thermal stability of the IS, and the olefin stabilizers were superior to the acid stabilizers. The stabilizing effect of oleic acid was the best for the acid stabilizers, and the C C in the oleic acid played a crucial role in the stabilization of the IS.
研究领域:
化学
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
STAR Protocols
·
2024
·
IF 1.3
Shihao Song,Binbin Cui,Xiaohan Kong,Yinyue Deng
Summary Here, we present a protocol for identifying the components of a quorum sensing signaling system in bacteria. We describe the steps for characterizing the novel response regulator and receptor of the cis -2-dodecenoic acid (BDSF) quorum sensing signaling system in Burkholderia cenocepacia . The technical assays of this protocol include generating a random mutant library, chromatin immunoprecipitation sequencing (ChIP-seq), electrophoretic mobility transfer assay (EMSA), microscale thermophoresis (MST), and molecular simulation docking. For complete details on the use and execution of this protocol, please refer to Li et al. 1 and Yang et al. 2
研究领域:
微生物学
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分子生物学
·
遗传学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）