ENERGY & FUELS
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2023
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IF 5.3
Chen Huang,Ying Zhang,Shuofan Li,Quan Shi,Suoqi Zhao,Linzhou Zhang
With the escalating global energy crisis and burgeoning environmental concerns as a result of the accumulation of used lubricating oil, the urgency and economic potential of recycling this waste is undeniably critical. Conventional methods, such as distillation and hydrogenation, often stumble upon operational difficulties as a result of thermochemical decomposition, while advanced procedures, like molecular distillation and membrane separation, face industrial scale-up, owing to prohibitive costs and limited separation capabilities. Herein, this study heralds the emergence of supercritical CO2 (SC-CO2) extraction, which can exemplify superior efficacy in addressing these concerns. Leveraging the high solvency under extreme pressure and low-temperature conditions, SC-CO2 can selectively separate undesirable components, reducing coke formation and simplifying subsequent refining stages. The comprehensive analysis, conducted using gas chromatography–mass spectrometry and high-resolution mass spectrometry, revealed the selectivity of SC-CO2 toward saturates with a smaller molecular weight. On the basis of this analysis, the optimal extraction condition was determined. Implementing a two-stage process at 70 °C and 10–20 MPa, we effectively eradicated residual small molecules and large polar compounds, yielding an intermediate fraction rich in isoparaffins and 1–4 ring naphthenes with a carbon distribution of C25–40. Notably, the recovery rate of saturates was 60%. Critically, the removal rate of undesirable components in recycled lubricating oil is remarkably high, reinforcing the practical viability and exceptional advantages of SC-CO2 extraction for lubricating oil recycling as a sustainable and economically rewarding solution to pressing global energy and environmental predicaments.
研究领域:
化学工程
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环境科学
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能源技术
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产品关联
DOI
高影响因子
Catalysts
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2021
·Vol. 12
·期 1
·12
·
IF 4.146
Hao Yuan,Zhao Wang,Shunjing Jin,Shanshan Xiao,Siming Liu,Zhiyi Hu,Lihua Chen,Baolian Su
Supported copper has a great potential for replacing the commercial palladium-based catalysts in the field of selective alkynes/alkadienes hydrogenation due to its excellent alkene selectivity and relatively high activity. However, fatally, it has a low catalytic stability owing to the rapid oligomerization of alkenes on the copper surface. In this study, 2.5 wt% Cu catalysts with various Cu:Zn ratios and supported on hierarchically porous alumina (HA) were designed and synthesized by deposition–precipitation with urea. Macropores (with diameters of 1 μm) and mesopores (with diameters of 3.5 nm) were introduced by the hydrolysis of metal alkoxides. After in situ activation at 350 °C, the catalytic stability of Cu was highly enhanced, with a limited effect on the catalytic activity and alkene selectivity. The time needed for losing 10% butadiene conversion for Cu1Zn3/HA was ~40 h, which is 20 times higher than that found for Cu/HA (~2 h), and 160 times higher than that found for Cu/bulky alumina (0.25 h). It was found that this type of enhancement in catalytic stability was mainly due to the rapid mass transportation in hierarchically porous structure (i.e., four times higher than that in bulky commercial alumina) and the well-dispersed copper active site modified by Zn, with identification by STEM–HAADF coupled with EDX. This study offers a universal way to optimize the catalytic stability of selective hydrogenation reactions.Keywords:hierarchically porous structure;selective hydrogenation reaction;unsaturated hydrocarbons;copper–zinc alloy;synergistic effect;1,3-butadiene
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
ACS Omega
·
2025
·
IF 4.3
Yong Qu,Jingmei Liu,Xiaodong Zhou,Lang Liu,Ruitao Ma,Yongguo Su,Chunmei Ma,Pengtao Sun
Low-temperature coal tar (LTCT) is the preferred raw material for the catalytic hydrogenation of coal tar. In order to study and popularize the technology of preparing fuel oil by hydrogenation of LTCT, it is necessary to research its composition and structural characteristics. Heavy hydrogenated coal tar (HHCT) from a company in Xinjiang, which is a mixture of hydrorefined tail oil distillate (>350 °C) and hydrotreated circulating tail oil (>350 °C). To make scientific and customized use of HHCT, the chemical composition and molecular structure characteristics of HHCT and its subcomponents were investigated by using elemental analysis (EA), infrared analysis (FT-IR), and nuclear magnetic resonance (1H NMR and 13C NMR) through fraction separation. Compared to other low-temperature coal tar (LTCT), the content of saturates (SA) in HHCT is 95.01 wt %, considerably higher than other LTCT samples, and the content of aromatics (AR), resins (RE), and asphaltenes (AS) is all much lower than other LTCT samples. Compared with the basic properties, elemental content, and refining performance of other crude oils, HHCT is good-quality oil with relatively small density, high H/C ratio, fewer heteroatoms, and low metal impurities, and is easy to refine and process. FT-IR and NMR results show that HHCT and SA are primarily constituted of long-chain n-alkanes possessing longer aliphatic chains and fewer branched chains. Aromatics are predominantly present in AR and mainly encompass bicyclic and tricyclic aromatics. HHCT and other fractions contain a small quantity of aromatic structures.
研究领域:
能源化学
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石油加工
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燃料化学
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分析化学
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煤化工
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有机地球化学
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材料化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY
·
2024
·
IF 5.7
Lin Zhu,Mingming Zhang,Boyan Gao,Hong Zhang,Hai Zhang,Yaqiong Zhang,Liangli Lucy Yu
In this work, the paraffin oil was first molecularly distilled into two mineral oil saturated hydrocarbons (MOSH) subfractions with their main carbon number range of C20–30 (84.58%) and C30–50 (89.65%), which were determined using a liquid chromatography–gas chromatography–flame ionization detector (LC-GC-FID) technique. Then, both female and male Fischer 344 (F344) rats were fed with the diets containing one of these two MOSH subfractions at the low (1.5 g/kg) or high dose (15 g/kg) for 6 months. It was found that the exposure of MOSH C20–30 subfraction could result in a significant increase of spleen weight index (4.64 ± 0.18 mg/g for female and 3.79 ± 0.31 mg/g for male rats) (P < 0.05), and irregular shape of white medulla, and the macrophage infiltration in mesenteric lymph node for both female and male rats, especially for the 15 g/kg MOSH C20–30-fed rats. Meanwhile, both MOSH C20–30 and C30–50 subfraction promoted inflammation and oxidative stress and had a negative effect on the immune function in both female and male rats. The metabolomics results further supported these observations, and indicated the down-regulation of cysteine and methionine metabolism, and glutathione metabolism pathway in female and male rats, respectively.
研究领域:
毒理学
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环境健康科学
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分子生物学
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产品关联
DOI
PubMed
高影响因子
Journal of Marine Science and Engineering
·
2025
·Vol. 13
·期 9
·1713
·
IF 2.8
Aigang Li,Shengjun Guo,Jianwen Deng,Hong Chen,Jinxuan Wu,Ru Jiang,Jing Tan,Lihua Cheng,Libo Zhang,Qinzhen Fan
Addressing IMO 2020 compliance, this study investigates marine fuel oil production from hydrotreated residues, focusing on mitigating excessive total sediment potential (TSP) caused by over-hydrotreatment. This study systematically investigates the impact of blending ratios of Fluid Catalytic Cracking (FCC) slurry oil with Residue Desulfurization (RDS) heavy oil on TSP, colloidal stability, and asphaltene structure evolution. Techniques such as XRD, SEM, and XPS were employed to analyze the structural changes in asphaltenes during the TSP exceeding process. The results indicate that as the FCC slurry oil blending ratio increases, TSP in the blended oil initially rises and then decreases. The peak TSP value of 0.41% occurs at a 10% FCC slurry oil blending ratio, primarily due to high-saturation hydrocarbons in RDS heavy oil disrupting the colloidal stability of asphaltenes in FCC slurry oil. When the blending ratio reaches 25%, TSP significantly decreases to 0.09%, attributed to the solubilizing effect of high aromatic compounds in the FCC slurry oil on the asphaltenes. The ω(Asp)/ω(Res) ratio mirrors the TSP trend, and the colloidal solubilizing capacity of asphaltenes increases with the blending ratio. Asphaltenes in RDS heavy oil exhibit a spherical structure, whereas those in FCC slurry oil show a layered structure. The precipitated asphaltenes in the blends primarily result from the aggregation of asphaltenes in FCC slurry oil, with heteroatoms (N, S, O) mainly originating from RDS heavy oil asphaltenes. During the early stage of blending, TSP formation is dominated by FCC slurry oil asphaltenes, but increasing the aromatic content in the system can significantly reduce TSP. This work provides theoretical and technical support for optimizing marine fuel blending processes in petrochemical enterprises.
研究领域:
石油工程
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燃料化学
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胶体与界面科学
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船用燃料
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石油化工工艺
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产品关联
DOI
高影响因子
NEW JOURNAL OF CHEMISTRY
·
2024
·Vol. 48
·期 8
·3573-3580
·
IF 2.7
Ruidong Li,Bo Zhao,Ganggang Chang,Shanchao Ke,Minjie Chen,Didi Dong,Chun Pu,Xiaoyu Yang
In the current investigation, the base-metal hollow multifunctional catalyst, Pd–IL@H-UiO-66-NH2, was fabricated utilizing a hydrothermal method followed by etching and supporting processes. The results of the effort demonstrate that Pd–IL@H-UiO-66-NH2 displays significantly enhanced activity and product selectivity in catalysis of the one-pot Knoevenagel condensation–hydrogenation reaction, as well as a high level of generality in promoting hydrogenation reactions of unsaturated hydrocarbons. The excellent properties of Pd–IL@H-UiO-66-NH2 are ascribed to its rationally designed spatial distribution of catalytically active sites within its hierarchical structure, which is comprised of surface wrinkles that increase hydrophobicity and exposure of the active sites, and hollow structures that serve as nanoreactors to enrich substrate interactions and improve mass transfer. Furthermore, the catalytic stability of Pd–IL@H-UiO-66-NH2 was shown to be largely maintained after its use in five successive catalytic cycles. The stability of the new tandem catalyst benefits from strong confinement effects associated with its hollow structure and electronic interactions between the Pd and ILs that effectively restrict leaching and aggregation of Pd nanoparticles (NPs).
研究领域:
催化
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材料科学
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化学工程
✓ 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）