CATALYSIS TODAY
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2022
·
IF 6.562
Lidan Deng,Qiao Chen,Xingmao Jiang,Xiaowei Liu,Zheng Wang
Propane dehydrogenation is a promising way to produce propylene . Catalysts with high propane conversion, selectivity to propylene , and stability are vital to this technology. In this work, we determined that the catalytic performance of Pt/SBA-15 can be significantly enhanced by introducing an appropriate amount of indium . A too low ratio of In/Pt (1/8) or too high of a ratio (2/1) is detrimental to the activity of the catalyst. When the nominal ratio of Pt to In is 1/1, the initial propane conversion and selectivity towards propylene over 1Pt1In/SBA-15 are highest among all catalysts tested at 57.06 % and 99.04 %, respectively. The conversion rate decreased to 39.63 % after 28 h of reaction, but selectivity was retained at greater than 99 %. Very little coke was deposited on the used 1Pt1In/SBA-15 catalyst. With catalyst characterization, it was proposed that Pt 1 In 1 alloy nanoparticles with surface-enriched In 2 O 3 were responsible for the selective dehydrogenation of propane.
研究领域:
催化化学
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材料科学
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DOI
高影响因子
RSC Advances
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2015
·Vol. 5
·期 110
·90904-90912
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IF 3.84
Yueling Cao,Junwei Wang,Maoqing Kang,Yulei Zhu
Hydrogenolysis of glucose and cellobiose, used as the model feedstocks, over Ni–WO3/SBA-15 catalysts has been investigated to probe the influencing factors for the conversion of cellulose to ethylene glycol (EG). The conversion of glucose and cellobiose to EG showed different dependencies on reaction temperature; a lower reaction temperature was needed for the former. Additionally, the surface atomic ratio of W to Ni on the Ni–WO3/SBA-15 catalysts was the key factor for the product distribution. Both glucose and cellobiose had their own optimum W–Ni ratio for the production of EG, and the ratio of W to Ni for glucose was slightly lower than that of cellobiose. On the other hand, the Ni–WO3/SBA-15 catalysts were thoroughly characterized by N2 adsorption–desorption, X-ray diffraction (XRD), hydrogen-temperature programmed reduction (H2-TPR), X-ray photoelectron spectroscopy (XPS) and transmission electron microscopy (TEM). The results indicated that the reducibility of Ni–WO3/SBA-15 catalysts with high Ni loading was more similar to that of pure NiO. More importantly, the change of surface atomic content of Ni and W of Ni–WO3 catalysts with various Ni loadings resulted from the surface W species of the catalysts being gradually covered by Ni species with the increase of Ni loading.
研究领域:
化学工程
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催化转化
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DOI
高影响因子
FUEL
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2022
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IF 8.035
Xiangyang Mao,Ge Liu,Bolun Yang,Jianxuan Shang,Bo Zhang,Zhiqiang Wu
Macromolecular volatiles are one of the important components of biomass pyrolysis products. Chemical looping reforming can efficiently convert macromolecular components into hydrogen-rich syngas. Oxygen carriers with good partial oxidation performance and excellent recycling performance are the key factor. In this work, the embeddedness strategy was proposed to regulate the micro-reaction environment of oxygen carriers and thus improve the recycling and partial oxidation performance. The characteristics of toluene chemical looping reforming via Fe 2 O 3 embedded in SBA-15 (Fe 2 O 3 @SBA-15) were studied in fixed-bed reactor. The performances of Fe 2 O 3 and Fe 2 O 3 @SBA-15 were compared. The effect of pure Fe 2 O 3 particle size, Fe 2 O 3 loading amount, and reaction temperature were investigated. Thermodynamic analysis results showed that the reaction could proceed spontaneously when the temperature was higher than 600℃. The experimental results showed that chemical looping reforming process could be divided into two stages, including partial oxidation and catalytic cracking. The main product in the first stage was syngas, while the main product in the latter stage was H 2 and coke. The Fe 2 O 3 particle size decreased from 5um to 30 nm, and the CO selectivity increased from 25.87% to 33.15%. This indicated that the nanocrystallization of Fe 2 O 3 would improve the partial oxidation performance. Compared with pure Fe 2 O 3 , the CO selectivity of Fe 2 O 3 @SBA-15 rose from 25.9% to 96.2%. The utilization rate of lattice oxygen and the conversion rate of toluene increased significantly. At 900℃, toluene was nearly completely converted, and the utilization rate of lattice oxygen reached 92.7%. The toluene conversion increased with the elevation of Fe 2 O 3 loading, and the CO selectivity always remained above 87.9%. With the elevation of reaction temperature from 700℃-900℃, toluene conversion increased from 30.5% to 95.6%, while CO selectivity decreased slightly. More importantly, the stability test results showed that after 10 cycles, toluene conversion rate only dropped by 1.9%, and the average concentration of gas products remained stable. The above results showed that the embeddedness of Fe 2 O 3 in SBA-15 could effectively improve CO selectivity, enhance the transmission and release of lattice oxygen, and elevate the catalytic performance and cycle stability of oxygen carriers.
研究领域:
化学工程
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材料科学
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DOI
高影响因子
POLYMER BULLETIN
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2020
·Vol. 78
·期 10
·5741-5753
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IF 2.014
Yue Longlong,Xie Qian,Yang Yifeng,Li Jing,Li Xiancai
The preparation of a lanthanum ion-imprinted polymer is described via surface ion imprinting, with polyethyleneimine as the functional monomer and SBA-15 as the matrix material. Its structure was characterized and analyzed, and static adsorption experiments were carried out to determine the best experimental conditions for the adsorption of lanthanum ions. The effects of initial concentration, temperature, adsorption time and pH on the adsorption of lanthanum ion surface-imprinted polymer were investigated. In addition, the regeneration performance of La(III)-IIP-PEI/SBA-15 on lanthanum ion was studied and showed that La(III)-IIP-PEI/SBA-15 has strong specific recognition ability and high reuse performance.
研究领域:
材料科学
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环境科学
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产品关联
DOI
高影响因子
MICROPOROUS AND MESOPOROUS MATERIALS
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2020
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IF 4.551
Yue Zhang,Li Wang,Nan Wang,Guohua Gao,Zhiyong Pan,Baoning Zong
Monodispersed mesoporous SBA-15 silica was synthesized by adding n -decane to conventional synthesis recipe. Pd catalysts for 2-alkyl-anthraquinone hydrogenation were then prepared on the as-synthesized SBA-15 and characterized by scanning and transmission electron micrographs, X-ray diffraction, XPS spectroscopy and N 2 adsorption-desorption. At the molar ratio of n -decane to P123 (C10/P123) ranging between 120 and 240, monodispersed SBA-15, together with the shortened length of pore channels, expanded size of mesopores and decreased proportion of micropores could be obtained. The Pd catalyst on SBA-15 synthesized with 240 in C10/P123 exhibited the superior catalytic performance. The initial hydrogenation rate of 2-ethyl-, tert-butyl- and amyl-anthraquinone increases by approximately 300%, 183% and 150% compared with that on SBA-15 synthesized using a recipe without n -decane, with the selectivity to active anthraquinone of >99%.
研究领域:
化学工程
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材料科学
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催化
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产品关联
DOI
高影响因子
APPLIED CATALYSIS A-GENERAL
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2016
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IF 4.012
Hua Wang,Yingge Guo,Cuirong Chang,Xinli Zhu,Xiao Liu,Jinyu Han,Qingfeng Ge
The number of strong acid sites on a hydrolysis catalyst accessible by the bulky cellulose limits its efficiency in the conversion and utilization of biomass-based resources. In this work, high surface area WZr/SBA-15 catalysts (>400 m 2 /g) were prepared by hydrothermal method and characterized using XRD, N 2 adsorption, TEM, Raman, UV–vis, XPS and FTIR of pyridine adsorption. The results showed that doping a moderate amount of ZrO 2 into the WO 3 /SBA-15 catalyst stabilized the tungstate species in the form of a polytungstate species as a result of the strong ZrO x -WO x interaction as well as increased the surface area of the catalyst. The resulting polytungstate species provided strong Brønsted acid sites for hydrolysis. Consequently, the cellobiose conversion was maximized at 5% ZrO 2 loading, corresponding to a maximized surface area and density of Brønsted acid sites. This catalytic activity is significantly higher than that of a WO 3 /ZrO 2 catalyst prepared using the conventional impregnation method, indicating the importance of mesoporous structure to the dispersion of active species and to the accessibility of the active sites by the bulky reactant. This result indicates that the density of the strong Brønsted acid sites with improved accessibility by the bulky reactant is essential to achieve a high hydrolysis activity.
研究领域:
化学工程
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催化材料
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DOI
高影响因子
INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES
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2020
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IF 5.162
Xin Wang,Lihong He,Jianrong Huang,Nanjing Zhong
In this study, SBA-15 was modified by halogen & haloalkanes and later used to immobilize lipases. The hydrolysis activity and the glycerolysis performance of the immobilized lipases was carefully studied. Highest activity of the immobilized Candida antarctica lipase B (CALB), Lipase from Aspergillus oryzae (AOL), Lecitase® Ultra (LU) and lipase from Rhizomucor miehei (RML) was respectively at 5577, 12000, 2822 and 11,577 U/g; in addition, the highest activity was obtained from the lowest or moderate lipase loading, at 25.73, 90.72, 89.52 and 30.56 mg/g respectively. The mechanism of lipase immobilization was studied and it was through interfacial activation. The halogen & haloalkanes modification of SBA-15 afforded considerable glycerolysis activity for diacylglycerols (DAG) preparation. CALB@SBA-15-CH 2 CH 2 (CF 2 ) 5 CF 3 and CALB@SBA-15-CH 2 CH 2 (CF 2 ) 7 CF 3 were suitable for DAG production, they both exhibited good reusability in glycerolysis reaction, with 117.36% and 93.06% of their initial glycerolysis activity retained respectively after ten cycles of reuse. The relationships between temperature with triacylglycerols (TAG) conversion were ln V 0 = 3.13–3.07/T and ln V 0 = 7.90–4.64/T respectively for CALB@SBA-15-CH 2 CH 2 (CF 2 ) 5 CF 3 and CALB@SBA-15-CH 2 CH 2 (CF 2 ) 7 CF 3 ; in addition, their activation energy ( Ea ) was respectively at 25.50 and 38.54 kJ/mol.
研究领域:
生物化学
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酶工程
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材料科学
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产品关联
DOI
PubMed
高影响因子
Journal of Oleo Science
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2020
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IF 1.304
Maomao Kou,Siting Feng,Nanjing Zhong
In this study, Lecitase® Ultra (LU) was immobilized onto the parent and the amino-functionalized SBA-15. The immobilization conditions were studied and the activity of the parent SBA-15 supported LU (SBA-15-LU) was found to be at 2177.78 ± 101.84 U/g. After 3-aminopropyl and n-(2-aminoethyl)-3-aminopropyl groups functionalization, enzymatic activity was increased to 3555.56 ± 200.21 and 3444.44 ± 346.41 U/g respectively. The immobilized LU samples were then used to catalyze glycerolysis. The possibility for diacylglycerols (DAG) and monoacylglycerols (MAG) production was evaluated and it was found only suitable for DAG production. In addition, the glycerolysis activity of the immobilized LU was impaired by the tert-pentanol and solvent-free was found suitable. Similar DAG content over 50 wt% could be obtained from glycerolysis by the three immobilized LU samples. The reusability in glycerolysis was evaluated, and 9.79 % of the initial glycerolysis activity was remained from the SBA-15-LU after 5 cycles of reuse. Encouragingly, after 3-aminopropyl and n-(2-aminoethyl)-3-aminopropyl groups functionalization, 62.93 and 83.91% of their initial activity was respectively remained after 5 cycles of reuse.
研究领域:
生物化学
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酶工程
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食品科学
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DOI
PubMed
高影响因子
Catalysis Science & Technology
·
2017
·Vol. 7
·期 23
·5540-5549
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IF 5.773
Xinqiang Feng,Chun Shen,Kaiyue Ji,Jiabin Yin,Tianwei Tan
Mesoporous solid acid catalyst WO3/SBA-15 exhibited high performance for the production of bio-based p-xylene (PX). After immobilization on SBA-15, isolated [WO4]2− tetrahedral species which were coordinatively unsaturated, were generated and functioned as Lewis acid centers. The ratio of Lewis to Brønsted acid sites varied in the range of 7.4 to 13.4 by adjusting the calcination temperature. A high ratio of Lewis to Brønsted acid sites and the mesoporous structure contributed to the high activity and stability: a selectivity of 88.0% for PX with a conversion of 64.4% and a carbon balance of 90.1% was achieved over 0.20-WO3/SBA-15-700. Compared with microporous Sn-Beta, the as-prepared catalyst showed better resistance to carbon deposition with a 20% higher yield. The spent catalyst could be easily regenerated by calcination at high temperature. The conversion decreased by 3% and no loss in PX selectivity was observed after five regeneration cycles. The as-prepared WO3/SBA-15 catalyst is highly active, stable and recyclable, and has high potential towards bio-based PX production.
研究领域:
化学工程
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催化科学
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绿色化学
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DOI
高影响因子
MICROPOROUS AND MESOPOROUS MATERIALS
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2015
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IF 3.453
Hui-Min Zhao,Chang-Miao Di,Lan Wang,Yuan Chun,Qin-Hua Xu
Mesoporous graphitic C 3 N 4 has been synthesized using a novel cross-linked bimodal mesoporous (CLBM) SBA-15 as a hard template. This cross-linked bimodal mesoporous SBA-15 template was prepared by adjusting the pH to alter the copolymer micelle size. The resulting mesoporous g -C 3 N 4 replicates the morphology of the mesoporous silica template, and numerous pore openings are formed on the surfaces. The mesoporous g -C 3 N 4 exhibits a high specific surface area and a large pore volume . The photocatalytic degradation activity of methyl orange on mesoporous g -C 3 N 4 is nearly 15.3 times as high as that on bulk- g -C 3 N 4 under visible light irradiation. The high photocatalytic performance of this sample is due to the high specific surface area and more readily accessible active sites.
研究领域:
材料科学
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化学工程
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产品关联
DOI
高影响因子
International Journal of Environmental Science and Technology
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2021
·Vol. 19
·期 8
·7205-7216
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IF 2.86
Wu Chunlai,Liu Qiong,Peng Chuanyun,Xu Wenwen
In this work, novel glutamic acid-functionalized SBA-15 was prepared for sensitive and selective lead and copper ions removal from wastewater sample. The material was characterized by X-ray diffractometry, scanning electron microscope, Brunauer–Emmett–Teller surface area measurement and Fourier transform infrared spectroscopy. The as-prepared material maintains the coordination properties of glutamic acid to lead and copper ions and exhibited better adsorption performance than that of pure SBA-15. The effects of different parameters such as pH of the solution, adsorption time, initial concentration, ion selectivity and regeneration were investigated on the Pb(II) and Cu(II) adsorption by the prepared adsorbent. It was found that the adsorption process can reach equilibrium within 20 min and can be described by pseudo-second-order kinetic model. Adsorption isotherm analysis showed that the adsorption was in accordance with Langmuir adsorption isotherm model, and the maximum adsorption capacity of lead and copper ions was 12.14 mg/g and 13.29 mg/g, respectively. In addition, common co-existed ions have no interference on Pb(II) and Cu(II) adsorption. Moreover, adsorption–elution cyclic results demonstrated that Pb(II)- and Cu(II)-adsorbed composite adsorbent could be effectively regenerated by 0.5 mol/L of HCl, and the regenerated adsorbent could be employed for repeated use without significant deterioration in its real performances, demonstrating the good stability of the adsorbents. Therefore, the composite adsorbent can be used potentially to remove Pb(II) and Cu(II) ions from water samples in practical applications for environmental remediation. Graphic abstract Glutamic acid-functionalized SBA-15 can be used as adsorbent for efficient adsorption/desorption of Pb(II) and Cu(II) from wastewater.
研究领域:
环境科学
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材料科学
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DOI
高影响因子
CELLULOSE
·
2020
·Vol. 27
·期 5
·2737-2756
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IF 4.21
Shen Zhi,Cai Ning,Xue Yanan,Yu Bo,Wang Jianzhi,Song Hao,Deng Hang,Yu Faquan
Abstract A sustained release of anti-infection drugs is beneficial for the reduction of required dressing change times and the protection of the granulation tissue against further infection. In this work, the strategy of encapsulating mesoporous SBA-15 particles in a permeable cellulose membrane (CM) was used in the preparation of antibacterial cellulose based composite membranes to depot store and deliver drugs with prolonged anti-microbial drug release characteristics. It was found that SBA-15 with the protection of phosphate buffered saline prefilled in SBA-15 mesoporous channel could resist strong alkali environment during composite membranes preparation and its mesoporous structure remained intact, which was verified by SEM, TEM and BET results. The resultant cellulose based composite membrane containing 30 wt% SBA-15 (denoted as P-CM-SBA (30%)) had achieved 3.6 wt% drug loading and demonstrated the sustained release of chloramphenicol for 250 h, which was resulted from SBA-15/cellulose structure-inducing two-stage release behavior. Strong antibacterial activity of P-CM-SBA (30%) against S. aureus and E. coli . could last 144 h. In addition, the tensile strength, water vapor transmission rate and swelling properties of P-CM-SBA (30%) conformed to the primary requirements of wound dressing materials. Therefore, cellulose based composite membrane with 30 wt% SBA-15 particles possesses the potential for the application of wound healing. Graphic abstract
研究领域:
材料科学
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生物医学工程
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药剂学
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DOI
高影响因子
危险品化学品经营许可证（带存储）