ENERGY & FUELS
·
2020
·
IF 3.421
Chenglong Wen,Jundong Xu,Xueman Wang,Yu Fan
A novel SO42–/ZrO2@SAPO-11 (SZ@SA-11) composite was synthesized via a two-step method, and the corresponding SZ@SA-11 supported Pt catalyst was applied to catalyze n-heptane hydroisomerization. First, UiO-66@SAPO-11 is produced by the growth of UiO-66 on SAPO-11 due to the covalent bonds between Zr and the oxygen in the hydroxyl groups of SAPO-11. Then, UiO-66@SAPO-11 is decomposed to form ZrO2@SAPO-11 via calcination in air, and the SZ@SA-11 composite is obtained by the impregnation of ZrO2@SAPO-11 with (NH4)2SO4 and subsequent calcination. Compared with the physical mixture of SO42–/ZrO2 and conventional SAPO-11 (SZ+SA-11), SZ@SA-11 possesses smaller ZrO2 particles and more tetragonal ZrO2. Moderate and strong Brønsted acid sites (MSBAS) are produced only via interactions between tetragonal ZrO2 and sulfate, so SZ@SA-11 with more tetragonal ZrO2 has a greater amount of MSBAS than SZ+SA-11. These advantages of SZ@SA-11 endow the corresponding Pt/SZ@SA-11 catalyst with a better performance for n-heptane hydroisomerization compared to Pt/(SZ+SA-11). In addition, compared with the other counterparts such as Pt/SZ and Pt/SA-11, Pt/SZ@SA-11 presents higher selectivity for total isomers (91.5%), higher selectivity for multibranched isomers (22.6%), and a lower cracking selectivity (8.1%) in n-heptane hydroisomerization. The strategy proposed herein provides a new insight into the acidity adjustment of the molecular-sieve-based catalysts for hydrocarbon hydroisomerization.
研究领域:
催化化学
·
能源化学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF THE ENERGY INSTITUTE
·
2023
·
IF 5.7
Saisai Liu,Jing Liu,Guanyi Chen,Jingang Yao,Beibei Yan,Weiming Yi,Chunyan Tian,Huijie Zao
Herein, spherical and nanosheet-like SAPO-11s were successfully synthesized hydrothermally and utilized to catalyze the methanol-to-gasoline (MTG) process. The nanosheet-like SAPO-11 (SAPO-11-A) had a thickness of about 10 nm, while the spherical SAPO-11 (SAPO-11-B) had a particle size of around 11 μm. Compared to SAPO-11-B, the property of SAPO-11-A was enhanced by 42.9% in specific surface area (SSA), 38.1% in mesopore volume (V me ) and 20.2% in acid amounts, respectively. In terms of catalytic performance during the MTG reaction, SAPO-11-A demonstrated superior results not only in the methanol conversion (95.82%), gasoline-range hydrocarbons selectivity (58.76%) and iso/nparaffin ratio (8.17) but also in suppressed coke deposition (2.56%) compared with those (90.63%, 50.95%, 4.75 and 5.73%, respectively) of SAPO-11-B. Additionally, the optimal MTG process conditions were identified utilizing SAPO-11-A, demonstrating a methanol conversion rate of 98.34%, a gasoline hydrocarbon selectivity of 67.61%, an isoparaffin selectivity of 36.01% and an iso/nparaffin ratio of 10.94 at 380 °C, weight hourly space velocity (WHSV) of 2 h −1 and 1 MPa. These results highlight the potential of nanosheet SAPO-11 to produce gasoline-range hydrocarbons rich in isoparaffins.
研究领域:
催化化学
·
能源材料科学
✓ 已验证
产品关联
DOI
高影响因子
ENERGY & FUELS
·
2019
·
IF 3.021
Meiqiu Hu,Hong Yuan,Wei Liu
Ordered mesoporous SAPO-11 molecular sieves (OMSMS) with a single mesoporous structure were prepared via a one-step hydrothermal method. Metal–acid bifunctional Pt/SAPO-11 (Pt/OMSMS-700) catalysts with Pt loadings of 1% and 2% were synthesized by a deposition–precipitation method using OMSMS-700 as a carrier. The OMSMS and Pt/OMSMS-700 were characterized using transmission electron microscopy (TEM), scanning electron microscopy (SEM), Brunauer–Emmett–Teller (N2-BET) analysis, and X-ray powder diffraction (XRD). TEM and small-angle XRD results revealed that the degree of order in the OMSMS increased as the calcination temperature increased from 500 to 700 °C. The N2-BET analysis revealed that the OMSMS had a mesoporous structure with an average pore diameter of 6.4–7.8 nm and a BET surface area of 149–171 m2/g. The sizes of the Pt nanoparticles supported on OMSMS-700 were in the range of 3 to 6 nm and displayed good dispersibility. The catalytic performance of Pt/OMSMS-700 during the decarboxylation of oleic acid to form C8–C17 alkanes under a CO2 atmosphere was investigated. As the reaction temperature increased from 320 to 360 °C, the total yield of C8–C17 alkanes initially increased and then decreased. Increasing the Pt loading led to an increased yield of C8–C17 alkanes. The total yield of C8–C17 alkanes reached 78% when 2 wt % Pt/OMSMS-700 was used at 340 °C for 3 h.
研究领域:
催化化学
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能源化学
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多相催化
·
生物燃料
·
材料化学
✓ 已验证
DOI
高影响因子
FUEL PROCESSING TECHNOLOGY
·
2019
·
IF 4.507
Lingmei Yang,Shiyou Xing,Hongzhe Sun,Changlin Miao,Ming Li,Pengmei Lv,Zhongming Wang,Zhenhong Yuan
In this study, a series of Ni/SAPO-11 catalysts with different Ni loadings were prepared by citric acid-assisted impregnation for the hydroisomerization of oleic acid to iso-alkanes. Serving as a chelating ligand, citric acid first promoted the dispersion of Ni nanoparticles loaded on SAPO-11. Because of its acid properties, citric acid facilitated the removal of aluminium oxide species, contributing to the formation of a mesoporous SAPO-11 structure. A maximum of 67.3 mol% of iso-alkanes was formed using 7Ni/SAPO-11 as a catalyst under optimal conditions of 360 °C, 4 h, and 4.0 MPa H 2 . After reusing for five cycles, the catalyst still exhibited 21.5 mol% isomer selectivity. The reaction pathways and catalytic mechanisms concerning the oleic acid hydroisomerization process were proposed and discussed. The hydroisomerization of oleic acid mainly depended on the catalyst's Lewis acid sites, with the assistance of the metal centre and Brönsted acid sites. The mesoporous structure of SAPO-11 facilitated the availability of a significant number of catalytic Lewis acid sites, which, together with the highly dispersed Ni centres, contributed to the enhanced product isomerization.
研究领域:
催化化学
·
材料科学
✓ 已验证
DOI
高影响因子
FUEL PROCESSING TECHNOLOGY
·
2023
·
IF 7.5
Saisai Liu,Jing Liu,Guanyi Chen,Jingang Yao,Beibei Yan,Weiming Yi,Zhanjun Cheng,Chunyan Tian,Huijie Zao
Syngas is a key precursor for synthesizing gasoline (C 5 -C 11 ) hydrocarbons, offering an efficient route for utilizing non-petroleum carbon sources. However, the conventional Fischer-Tropsch synthesis (FTS) process faces a constraint with a maximum 45% selectivity for C 5 -C 11 , attributed to the Anderson-Schultz-Flory (ASF) distribution. Herein, bifunctional catalysts comprising ZnZrO x with different Zr/Zn ratios along with SAPO-11 zeolite sieves featuring varied morphologies like nanosheets (SA-A), petals (SA-B), and spheres (SA-C) have been effectively formulated and employed for the syngas-to-gasoline hydrocarbons (STG) reaction. Notably, the selectivity toward C 5 -C 11 far exceeded the ASF limits. Under identical reaction parameters, the Zn 1 Zr 4 O x /SA-A catalyst demonstrated notable enhancements of 6.6% and 26.2% in CO conversion, along with 4.6% and 7.6% increases in C 5 -C 11 selectivity, as compared to that of Zn 1 Zr 4 O x /SA-B and Zn 1 Zr 4 O x /SA-C catalysts, respectively. Furthermore, under the ideal conditions (380 °C, 4.5 MPa and gas hourly space velocity (GHSV) of 2400 mL min −1 g −1 ), Zn 1 Zr 4 O x /SA-A exhibited an exceptional C 5 -C 11 selectivity of 69.8% (CO 2 -free) alongside a single-pass CO conversion of 30.4%. Impressively, isoparaffin constituted 39.2% of the total composition , with the iso/n-paraffin ratio reaching 11.8. Even after 100 h, the catalyst maintained its remarkable catalytic activity , with the CO conversion and C 5 -C 11 selectivity maintaining levels of 27.5% and 66.85%, respectively.
研究领域:
化学工程
·
催化科学
✓ 已验证
产品关联
DOI
高影响因子
ENERGY & FUELS
·
2021
·
IF 3.605
Meiqiu Hu,Xiaolong Liu,Hong Yuan,Jingye Ma
An in situ encapsulation process was used to prepare ordered worm-like mesoporous Pt@SAPO-11 catalysts with different Pt loadings. Transmission electron microscopy images showed that Pt nanoparticles encapsulated within the SAPO-11 support mesopores were uniformly distributed and highly dispersed and had a narrow particle size distribution of 2–7 nm. Scanning electron microscopy indicated that increasing the Pt loading from 0.6 to 1.6 wt % did not significantly change the crystalline morphology of the catalyst, although the crystallinity decreased slightly. The specific surface area and average pore diameter of the Pt@SAPO-11 were in the ranges of 72–116 m2/g and 8.1–9.5 nm, respectively, which are determined by the Brunauer–Emmett–Teller method and Barrett–Joyner–Halenda method, respectively. The NH3 thermal-programmed desorption established that increasing the Pt loading gradually decreased the total NH3 desorption and that a loading of 1.2 wt % produced the highest concentration of medium-strong acid sites (6.2 cm3/g STP). X-ray photoelectron spectroscopy and H2 temperature-programmed reduction showed that a Pt loading of 1.2 wt % gave the strongest interaction between Pt nanoparticles and the SAPO-11 support. The Pt@SAPO-11 catalysts were used for the preparation of C8–C17 alkanes by decarboxylation of oleic acid. Employing a reaction temperature of 340 °C, a CO2 atmosphere, a Pt loading on the catalyst of 1.2 wt %, and a reaction time of 4 h, 100% oleic acid conversion was obtained together with an 80% yield of C8–C17 alkanes.
研究领域:
催化化学
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
FUEL PROCESSING TECHNOLOGY
·
2018
·
IF 3.956
Ping Zhang,Haiyan Liu,Yuanyuan Yue,Haibo Zhu,Xiaojun Bao
Hydroisomerization of light straight-chain paraffins to their branched isomers especially di-branched ones is considered as a promising technology to produce clean gasoline blending component with high octane number . In this article, we report a superior hydroisomerization catalyst that is based on a SAPO-11 molecular sieve (SAPO-11-H) simultaneously with smaller crystal size, hierarchical pore structure and enhanced acidity. This novel SAPO-11-H was successfully synthesized via a two-stage hydrothermal crystallization route by simultaneously using a cationic surfactant cetyltrimethylammonium bromide (CTAB) as template and a nonionic copolymer poly(ethylene oxide)‑ block ‑poly(propylene oxide)‑ block ‑poly(ethylene oxide) (F127) as crystal growth inhibitor . During the crystallization, CTAB plays roles in enhancing the acidity and creating the mesoporous structure, and F127 serves as a crystal growth inhibitor to control the crystals size. Compared to two Pt catalysts supported on a conventional SAPO-11 and a commercial SAPO-11, the SAPO-11-H supported Pt/SAPO-11-H catalyst with the same Pt loading (0.5 wt%) exhibited superior selectivity to di-branched C 8 isomers and dramatically lower cracking selectivity in n ‑octane hydroisomerization. The outstanding performance of Pt/SAPO-11-H is mainly attributed to two factors: one is the highly exposed pore mouths and hierarchical pore structure of SAPO-11-H that benefit the formation of di-branched isomers and avoid the cracking of the resultant di-branched isomers, and the other is the enhanced acidity that boosts the hydroisomerization activity.
研究领域:
化学工程
·
催化材料科学
✓ 已验证
产品关联
DOI
高影响因子
CATALYSIS LETTERS
·
2025
·Vol. 155
·期 3
·1-11
·
IF 2.4
Wen Chenglong,Liu Kang,Lu Yi,Wu Xintian,Li Shuning,Lu Mohong,Zhu Jie,Li Mingshi,Song Chunshan,Lu Xiaosong
Ni/SAPO-11 catalysts with highly dispersed Ni (TA-Ni/SA-11) were prepared using tartaric acid as a dispersant. The effect of the tartaric acid content on the physiochemical properties of the TA-Ni/SA-11 catalysts and their n-heptane hydroisomerization performance were investigated. TA-Ni/SA-11 exhibits smaller Ni particles and more Ni active sites in comparison to conventional Ni/SAPO-11 prepared via the impregnation method due to the interaction between tartaric acid and Ni 2+ . As the molar ratio of tartaric acid and Ni 2+ (n TA /n Ni ) increases, the number of Ni active sites in TA-Ni/SA-11 rises, while the surface area and relative crystallinity decrease because of the dealumination of SAPO-11. When n TA /n Ni is 0.75, 0.75TA-Ni/SA-11 presents the highest n-heptane conversion of 82.4% and isomer selectivity of 90.5%, as well as the lowest cracking selectivity of 9.0% at 380 °C, 1.5 MPa, 2 h − 1 , and a volume ratio of H 2 to n-heptane of 400 among these catalysts. Graphical
研究领域:
催化化学
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材料科学
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产品关联
DOI
高影响因子
JOURNAL OF MATERIALS SCIENCE
·
2017
·Vol. 52
·期 8
·4460-4471
·
IF 2.599
Chen Zhou,Dong Yunyun,Jiang Shaoyang,Song Wenjing,Lai Weikun,Yi Xiaodong,Fang Weiping
Hierarchical SAPO-11 was successfully synthesized without a secondary template by changing the hydrothermal crystallization temperature. SAPO-11 with a larger external surface area, more acidity, and a large number of external active sites was constructed through a novel two-step crystallization strategy. Both precrystallization step and the low-temperature crystallization step were confirmed to be indispensable conditions for constructing hierarchical SAPO-11. After loading Pt nanoparticles by incipient wetness impregnation, the heptane hydroisomerizations based on 0.5 wt% Pt/C-SAPO-11-200 and 0.5 wt% Pt/T-SAPO-11-120 catalysts were carried out in a fixed-bed at a total pressure of 1.5 MPa with a H 2 /n-heptane volumetric of 400 and WHSV = 10 h −1 . A conversion level of 75.7% of 0.5 wt% Pt/T-SAPO-11-120 catalyst was reached, which was higher than that of 0.5 wt% Pt/C-SAPO-11-200 catalyst (64.3%) at 300 °C. The enhanced performance achieved was attributed to the improved effect of the support, in terms of not only better mass transport and higher number of exposure active sites but also improved dispersity and decrease in the size of Pt particles.
研究领域:
材料科学
·
催化化学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF ANALYTICAL AND APPLIED PYROLYSIS
·
2024
·
IF 5.8
Xin Su,Chunquan Liu,Jing Liu,Guanyi Chen,Beibei Yan,Jingang Yao,Zhanjun Cheng,Weiming Yi
Arundo donax, acknowledged for its elevated energy content, substantial biomass yield and rapid growth, stands as an alluring candidate for biofuel production. In this investigation, a molecular sieve-based catalyst was utilized to scrutinize the catalytic fast pyrolysis (CFP) of Arundo donax, aiming for the production of naphtha-range compounds. The study also encompassed the evaluation of pyrolysis product yields within a fixed-bed reactor. The systematic exploration included an assessment of the impacts arising from catalyst type, temperature, weight hourly space velocity (WHSV), and N 2 flow rate. The results demonstrated that at 500 °C, WHSV of 1 h −1 and N 2 flow rate of 300 ml/min, SAPO-11 exhibited a selectivity of 64.55% to naphtha-range compounds and 64.55% to isomerous naphtha-range compounds. This was in stark contrast to the control group, which contained no catalyst (with a selectivity of 41.40% and 3.19%, respectively), SAPO-41 (with a selectivity of 11.02% and 9.55%, respectively) and HZSM-5 (with a selectivity of 59.89% and 53.51%, respectively). Additionally, SAPO-11 yielded the highest bio-oil compared to other catalysts (SAPO-11 of 28.52 wt% > none of 19.48 wt% > HZSM-5 of 18.90 wt% > SAPO-41 of 13.11 wt%). The conclusions drawn from these findings imply that the synthesized SAPO-11 catalyst exhibited superior catalytic activity and isomerization proficiency in contrast to other catalysts (SAPO-41 and HZSM-5). Remarkably, under the specified conditions of SAPO-11 catalyst, temperature = 500 °C, WHSV = 1 h −1 and N 2 flow rate = 200 ml/min, the CFP process yielded a remarkable maximum absolute yield of the naphtha-range compound at 25.82 wt%, with an isomerized naphtha-range compound absolute yield of 25.35 wt%.
研究领域:
能源植物学
·
催化化学
✓ 已验证
产品关联
DOI
高影响因子
Inorganic Chemistry Frontiers
·
2022
·Vol. 9
·期 15
·3679-3691
·
IF 7.779
Lei Fan,Lianming Zhao,Yuchao Lv,Tinghu Wang,Yupeng Tian,Jianye Fu,Xinmei Liu
The synthesis of highly-dispersed non-noble metal based catalysts and their application in hydrogenation/dehydrogenation still remain challenging. Therefore, it is of great importance to protect metals from aggregation in both calcination and reduction processes. In this research, density functional theory (DFT) calculations were used to elucidate the stabilization effect of ionic liquid [Bmim][BF4] on Ni in the reduction process, showing that [Bmim][BF4] could efficiently inhibit Ni aggregation on the support. By further analysis combined with theoretical calculations, we found that the degree of metal dispersion before reduction directly determines the effect of [Bmim][BF4]. Guided by the DFT results, the method of co-assisted preparation of Ni/SAPO-11 using [Bmim][BF4] and lysine was adopted. Lysine forms a coordination compound with nickel oxides. The steric hindrance generated by the Ni–lysine complex can effectively inhibit the aggregation of nickel oxides during the calcination process. The DFT calculations revealed that during the reduction process, [BF4−] plays a dominant role in stabilization and electronic modulation by directly interacting with Ni on the support. The combination effects of [Bmim][BF4] and lysine effectively inhibit metal aggregation, leading to ultra-small nickel particles with a mean size of 4.4 nm over the obtained catalyst. Furthermore, the presence of [Bmim][BF4] also tunes the electronic state of Ni species. Using hexane isomerization as a probe reaction, the result indicates the excellent catalytic activity of the obtained catalyst (≈93.7% isomer selectivity at 63.5% conversion), much superior to that of Ni/SAPO-11 obtained from the traditional impregnation route (≈75.8% isomer selectivity at 64.6% conversion). This work provides a new method for the preparation of highly effective non-noble metal supported catalysts.
研究领域:
催化化学
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材料科学
·
理论计算
✓ 已验证
产品关联
DOI
高影响因子
APPLIED CATALYSIS A-GENERAL
·
2013
·
IF 3.41
Qiying Liu,Hualiang Zuo,Tiejun Wang,Longlong Ma,Qi Zhang
Nano-sized SAPO-11s were hydrothermally synthesized with using di-n-propylamine (DPA) as structure-directing agent in mixed n-tetradecanoamine–n-propanol–H 2 O medium and the Ni/SAPO-11 catalysts were prepared by incipient wetness impregnation. The catalysts was characterized by XRD, SEM, BET, H 2 -TPR, NH 3 -TPD and TG techniques and their catalytic performance was tested in hydrodeoxygenation (HDO) of palm oil to hydrocarbon fuels. Surfactant n-tetradecanoamine could mediate the minimum SAPO-11 sizes into 20–50 nm. As comparing to the commercial SAPO-11, the nano-sized SAPO-11s presented significantly enlarged surfaces and mesoporous volumes, which offered sufficient space and strong interactions for dispersing Ni. One-step HDO of palm oil demonstrated that the nano-sized SAPO-1 supported Ni catalysts showed the high yield (80%) of liquid hydrocarbons, high isomerization selectivity (80%) and excellent stability due to that the catalyst presented appropriate acidity, higher Ni dispersity, balance of metal (Ni) and acid (SAPO-11) functionalities and fast diffusion for bulky palm oil and products. These promotion effects observed over the nano-sized SAPO-11 supported Ni catalysts indicated the potential application in biorefinery of vegetable oils to hydrocarbon fuels.
研究领域:
催化化学
·
可再生资源转化
·
能源材料科学
✓ 已验证
DOI
高影响因子