JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY
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2015
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IF 2.912
Chang Li,Hanbing Jia,Mingyue Shen,Yuting Wang,Shaoping Nie,Yi Chen,Yongqiang Zhou,Yuanxing Wang,Mingyong Xie
The capacities of six antioxidants to inhibit the formation of 3-monochloropropane-1,2 diol (3-MCPD) esters were examined in this study. Inhibitory capacities of the antioxidants were investigated both in chemical models containing the precursors (tripalmitoyl glycerol, 1,2-dipalmitoyl-sn-glycerol, monopalmitoyl glycerol, and sodium chloride) of 3-MCPD esters and in oil models (rapeseed oil and sodium chloride). Six antioxidants, butylated hydroxytoluene (BHT), butylated hydroxy anisole (BHA), tert-butyl hydroquinone (TBHQ), propyl gallate (PG), l-ascorbyl palmitate (AP), and α-tocopherol (VE), were found to exhibit inhibiting capacities on 3-MCPD ester formation both in chemical models and in oil models. TBHQ provided the highest inhibitory capacity both in chemical models and in oil models; 44% of 3-MCPD ester formation was inhibited in the presence of TBHQ (66 mg/kg of oil) after heating of rapeseed oil at 230 °C for 30 min, followed by PG and AP. BHT, BHA, and VE appeared to have weaker inhibitory abilities in both models. VE exhibited the lowest inhibition rate; 22% of 3-MCPD esters were inhibited in the presence of VE (172 mg/kg of oil) after heating of rapeseed oil at 230 °C for 30 min. In addition, the inhibition rates of PG and VE decreased dramatically with an increase in temperature or heating time. The results suggested that some antioxidants, such as TBHQ, PG, and AP, could be the potential inhibitors of 3-MCPD esters in practice.
研究领域:
食品科学
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化学
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产品关联
DOI
PubMed
高影响因子
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
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2014
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IF 2.93
Shurong Wang,Qinjie Cai,Fan Zhang,Xinbao Li,Li Zhang,Zhongyang Luo
Catalytic reforming of three typical bio-oil model compounds, phenol, acetic acid and hydroxyacetone , has been carried out over a Ni/nano-Al 2 O 3 catalyst. Al 2 O 3 , in the form of nano-rods of length approximately 40 nm, was selected as the catalyst support. The catalyst showed superior performance in terms of activity and stability. The conversions for phenol, acetic acid and hydroxyacetone reached 84.2%, 98.2% and 98.7%, respectively, at the reaction temperature of 700 °C. The corresponding hydrogen yields were 69%, 87% and 97.2%. The catalyst maintained its high reactivity for more than 10 h in the catalytic reforming of three model compounds. The influences of steam to carbon ratio, catalyst loading and Ni content in the catalyst on the reforming performance were also investigated. In addition, the possible decomposition pathways for phenol, acetic acid and hydroxyacetone are proposed.
研究领域:
能源化学
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催化科学
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DOI
高影响因子
ENVIRONMENTAL TECHNOLOGY
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2023
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IF 2.8
Songyuan Hao,Hong Yuan,Huiliang Zhou
Ni-Cu/Al-KCC-1 catalysts with different metal contents were prepared using fibrous nano-silica (Al-KCC-1) as a support. Field emission scanning electron microscopy observations showed that the spherical particle morphology and fibrous structure of the Al-KCC-1 were not changed after metal loading. Transmission electron microscopy images demonstrated that the introduction of copper improved the dispersion of the nickel, while X-ray diffraction and hydrogen temperature-programmed reduction confirmed the formation of a Ni-Cu alloy. The N2-Brunauer–Emmett–Teller specific surface areas of the catalysts were in the range of 269–378 m2/g and the average pore diameters were 7.988–12.078 nm. These Ni-Cu/Al-KCC-1 catalysts were used to promote the cracking of waste cooking oil model compound (WCOMC) to produce H2 and carbon nanotubes (CNTs), and the 10 wt% Ni-5 wt% Cu/Al-KCC-1 exhibited the highest catalytic activity. At a WCOMC flow rate of 0.04 mL/min and 750 °C, the instantaneous volume fraction of H2 reached 49.8 vol% and the content of H2 in the gaseous product was close to 71.4 vol%.
研究领域:
化学工程
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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 POROUS MATERIALS
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2023
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IF 2.6
Zhang Guoliang,Liu Hao,Yuan Hong
Ni/KIT-6 catalysts were synthesized using ordered mesoporous silica-based KIT-6 molecular sieves as a support in conjunction with an impregnation method. These catalysts were characterized using transmission electron microscopy, X-ray diffraction, N 2 -Brunauer–Emmett–Teller surface area analysis and hydrogen temperature-programmed reduction. The results showed good dispersion of metallic nickel (Ni) on the surface of the KIT-6 and strong interactions between the metal and carrier. The surface areas of the catalysts were in the range of 387–788 m 2 /g and the average pore diameters were in the range of 5.5–8.6 nm. Following H 2 reduction, these materials were applied to the catalytic cracking of a waste cooking oil model compound to produce hydrogen and carbon nanotubes in a laboratory-scale fixed bed reactor. A catalyst with a Ni loading of 10 wt% showed optimal catalytic activity. Reaction trials using an oil flow rate of 0.04 mL/min at 750 °C provided an instantaneous H 2 volume-based proportion of 44.2% with a maximum H 2 concentration in the gaseous products of 59.0% after 25 min. Analyses by thermogravimetry and Raman spectroscopy indicated that carbon nanotubes deposited on the spent catalyst had good oxidative stability and a high degree of graphitization.
研究领域:
化学工程
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材料科学
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产品关联
DOI
高影响因子
FUEL
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2020
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IF 5.578
Xingfei Tang,Wentao Ding,Hao Li
Bio-oil, one of significant renewable energy, was blocked from its direct application by thermodynamic instability due to the high oxygen content, so its deoxygenation needs urgent solution. Avoiding the disadvantages of the traditional catalytic method, such as harsh reaction conditions, potential explosion risk and environmental pollution, we utilize solid-acidic zeolites as low-load Pd-based catalyst supports instead of corrosive acid additives, with polymethylhydrosiloxane (PMHS) as the hydrogen-supplying agent, to achieve efficient hydrodeoxygenation of bio-oil models (carbonyl compounds) under mild conditions. The reaction conditions such as Si/Al ratio of HZSM-5 zeolite, temperature, solvent, and the type of Pd salts precursor are optimized. In particular, we have found that polar protic solvents improve catalytic efficiency by promoting proton transfer in the reaction. In an open-to-air, 97.9% ethylbenzene yield can be obtained for acetophenone conversion under mild conditions (0.5 wt% Pd/HZSM-5(18), 65 °C, 3 h, n-butanol as solvent), which is more efficient and environmental friendly than currently reports. Meanwhile, hydrogenation–dehydration mechanism was proposed, and the Brønsted acid in HZSM-5 promotes the dehydration of the alcohol (rate-limiting step) by efficiently accelerating the removal of hydroxyl groups and the proton transfer of the reaction. Furthermore, the catalytic scheme exhibits the excellent stability (reusable seven times) and versatility. The potential of a green catalytic technology using with PMHS opens attractive opportunities for bio-oil upgrading.
研究领域:
能源化学
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催化化学
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产品关联
DOI
高影响因子
SCIENCE OF THE TOTAL ENVIRONMENT
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2018
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IF 4.61
Guanyi Chen,Ruixue Zhang,Wenchao Ma,Bin Liu,Xiangping Li,Beibei Yan,Zhanjun Cheng,Tiejun Wang
The catalytic cracking upgrading reactions over HZSM-5 of different model compounds of bio-oil have been studied with a self-designed fluid catalytic cracking (FCC) equipment. Typical bio-oil model compounds, such as acetic acid, guaiacol, n-heptane, acetol and ethyl acetate, were chosen to study the products distribution, reaction pathway and deactivation of catalysts. The results showed: C 6 –C 8 aromatic hydrocarbons , C 2 –C 4 olefins , C 1 –C 5 alkanes, CO and CO 2 were the main products, and the selectivity of olefins was: ethylene > propylene > butylene . Catalyst characterization methods, such as FI-IR, TG-TPO and Raman, were used to study the deactivation mechanism of catalysts. According to the catalyst characterization results, a catalyst deactivation mechanism was proposed as follows: Firstly, the precursor which consisted of a large number of long chain saturated aliphatic hydrocarbons and a small amount C C of aromatics formed on the catalyst surface. Then the active sites of catalysts had been covered, the coke type changed from thermal coke to catalytic coke and gradually blocked the channels of the molecular sieve, which accelerated the deactivation of catalyst.
研究领域:
化学工程
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催化科学
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产品关联
DOI
PubMed
高影响因子
INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
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2022
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IF 4.326
Yanli Zhang,Zihao Su,Ke Xue,Jiafu Xing,Dingchao Fan,Jianguang Qi,Zhaoyou Zhu,Yinglong Wang
Ionic liquids (ILs) have been proposed as promising green solvents for the separation of azeotropes. In this work, the efficient separation of methyl tert-butyl ether (MTBE) from gasoline model oil using ILs was investigated from the molecular level (i.e., extraction mechanism) to process system integration (i.e., process simulation). The quantum chemistry (energy analysis and weak interaction) and molecular dynamics were implemented to explore the separation mechanism. Compared to benchmark organic solvents, 1-butyl-3-methylimidazolium nitrate ([BMIM][NO3]) and 1-ethanyl-3-methylimidazole hydrogen sulfate ([EMIM][HSO4]) had the highest extraction rate, and [NO3]− played a major role in the separation process. The extraction performance of MTBE from gasoline model oil using ILs was evaluated. [BMIM][NO3] had the highest extraction effect at 298.15 K. The efficient process of liquid–liquid extraction and extractive distillation with [BMIM][NO3] as an extractant were designed, which confirmed that ILs are promising extractants. This work provides a theoretical guideline to search and develop task-specific ILs for efficient recovery of MTBE.
研究领域:
化学工程
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计算化学
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产品关联
DOI
高影响因子
JOURNAL OF CHEMICAL TECHNOLOGY AND BIOTECHNOLOGY
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2023
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IF 3.4
Guoliang Zhang,Haoyu Liu,Sen Fu,Hong Yuan
BACKGROUND A series of ZSM-5@KIT-6 composite molecular sieve catalysts was prepared by encapsulating ZSM-5 as a substrate in the mesoporous material KIT-6. The intent was to use these catalysts to promote the catalytic cracking of a waste cooking oil model compound (WCOMC) to produce light olefins. RESULTS The morphology, structural characteristics and acidity of each of the resulting catalysts were characterized by X-ray diffraction, transmission electron microscopy, N 2 -Brunauer–Emmett–Teller (N 2 -BET) surface area analysis and temperature-programmed ammonia desorption. The results showed that ZSM-5 was successfully coated with KIT-6. The BET surface areas of these catalysts ranged from 345 to 792 m 2 g −1 and the specimens had average pore sizes in the range of 2.37–5.51 nm. Total acidity increased with increases in the mass-based proportion of ZSM-5 in the material. CONCLUSION The catalytic cracking of WCOMC was studied in a lab-scale fixed-bed apparatus. Trials at a reaction temperature of 600 °C using the material having a mass-based ZSM-5 proportion of 80.0% (ZK-80) gave the highest gas-phase yield of light olefins of 43.8%. After 6000 min, the catalytic performance of this material remained stable, demonstrating a resistance to carbon deposits. The superior activity of the present composite catalysts can be ascribed to improvements in pore structure and acid strength distribution. © 2023 Society of Chemical Industry (SCI).
研究领域:
化学工程
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材料科学
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产品关联
DOI
高影响因子
ACS Omega
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2024
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IF 3.7
Wenbo Luo,Haoyu Liu,Hong Yuan,Hao Liu
Hierarchical zeolites can provide multidimensional spatial networks and, therefore, have significant potential as catalysts for the cracking of biomass to generate light olefins. The present work synthesized the diquaternary ammonium-type surfactant [C18H37–N+(CH3)2–(CH2)6–N+(CH3)2–C6H13]Br2, incorporating hydrophobic 18-carbon alkyl groups for usage as a structure-directing agent. This compound was subsequently used to prepare nanosheets of a hierarchical ZSM-5 two-dimensional zeolite (HNZSM-5) through a one-pot hydrothermal method. The crystal phase, morphology, and hierarchical structure of the HNZSM-5 were analyzed using various techniques, including X-ray diffraction, electron microscopy, and N2 adsorption/desorption. When applied to the catalytic cracking of a waste cooking oil model compound, the HNZSM-5 exhibited superior activity and stability compared with a conventional ZSM-5. This performance was attributed to the more accessible acid sites and unique lamellar structure of the former material. The HNZSM-5 also outlasted the conventional zeolite, showing deactivation after 45 h of reaction compared with 20 h, indicating exceptional stability and excellent resistance to coking.
研究领域:
材料科学
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催化化学
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产品关联
DOI
PubMed
高影响因子
FUEL
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2019
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IF 5.128
Yiming Zhang,Xiefei Zhu,Liqiang Zhang,Xifeng Zhu
In this study, a bio-oil model compound of walnut shell pyrolysis oil was selected. The microemulsions of diesel and model compound were produced using Span80 and Tween 80 as surfactants. The microemulsions were quantificationally analyzed to investigate the solubilization capacity of bio-oil characteristic components in diesel. The effects of surfactant concentration and initial volume ratio of bio-oil model compound to diesel (B/D ratio) on the solubilization capacity of bio-oil characteristic components in diesel were investigated. The heating value, kinematic viscosity, elemental analysis and thermogravimetric analysis of microemulsion were also conducted. Experimental results indicated that the suitable concentration of surfactant was 0.3 mol/L–0.45 mol/L, and the optimum B/D ratio was 4:12 for the bio-oil model compound. The dissolubility of m-cresol and guaiacol in microemulsion was much better than that of water and acetic acid. The heating value and the kinematic viscosity of microemulsion decreased slightly as the B/D ratio increased. Increasing the surfactant concentration contributed to a more pronounced increase in the kinetic viscosity and a significant decrease in the heating value. The influence of surfactant concentration on the fuel properties and thermogravimetric characteristics was stronger than that of B/D ratio.
研究领域:
能源科学
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化学工程
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生物质能
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DOI
高影响因子
MICROPOROUS AND MESOPOROUS MATERIALS
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2025
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IF 4.7
Zhang Yanting,Ding Yunlong,Guo Yunya,Wang Wenfeng,Li Xiaofeng,Dou Tao
The development of mesoporogen-free synthetic routes for hierarchical ZSM-5 zeolites is critical to advancing their application in diffusion-constrained catalytic processes such as heavy oil cracking. Here, we develop a mesoporogen-free strategy through synergistic control of seed solution temperature (70-170 °C) and addition amount (0.8-50 wt%). The synthesized zeolites were characterized using techniques such as X-ray Diffraction (XRD), Scanning electron microscope (SEM), Transmission electron microscopy (TEM), N 2 adsorption-desorption, ammonia temperature-programmed desorption (NH 3 -TPD), and pyridine-infrared (Py-IR). The results show that the sample is rich in mesopores and has well-preserved microporosity. Control experiments under TPAOH conditions equivalent to the seed solution addition amounts and with room-temperature-dried seed solids equivalent to the seed solution were conducted to highlight the critical role of seed solutions. Notably, seed solutions stored for three months retained their effectiveness in synthesizing phase-pure ZSM-5 zeolites, demonstrating exceptional stability. In tetralin (heavy oil model) cracking tests, the optimized zeolite (HZ-T100-A50) achieved 90 % conversion within 2 hours, which is 20 % higher than HZ-T100-A0.8, attributed to enhanced reactant accessibility. This study not only provides an eco-friendly method for synthesizing hierarchical ZSM-5 zeolites without mesoporous templates but also deepens the understanding of seed solution impacts, offering an important basis for optimizing zeolites synthesis and application.
研究领域:
材料科学
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催化化学
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化学工程
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多孔材料
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石油炼制
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）