APPLIED CATALYSIS A-GENERAL
·
2025
·
IF 4.8
Xuying Bian,Hualiang An,Xinqiang Zhao,Yanji Wang
The selective hydrogenation of dimethyl toluene-2,4-dicarbamate (TDC) to methyl cyclohexyl-2,4-dicarbamate (HTDC) is an important process for non-phosgene synthesis of methylcyclohexane-2,4-diisocyanate (HTDI). We prepared Rh/γ-Al 2 O 3 catalysts with an Rh particle size of 1.8–6.7 nm and studied size effect on TDC selective hydrogenation. The results showed that the catalytic activities of Rh/γ-Al 2 O 3 increase monotonously with increasing Rh particle size. This demonstrated that Rh/γ-Al 2 O 3 catalyst dedicates a negative size effect or an antipathetic structure sensitivity. Based on the characterization, we found that the geometric property of Rh is the main factor affecting the activity of catalyst. Combined with the proposed Rh particle model, it was inferred that the Rh (111) plays a major role in the TDC selective hydrogenation and the terrace sites are beneficial to promote the adsorption of TDC. The study on size effect can provide a guidance for the design and preparation of highly efficient Rh-based catalysts for TDC selective hydrogenation.
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
INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
·
2018
·
IF 3.141
Hongqin Ma,Xiao Sun,Meijie Wang,Jiasheng Zhang
This research focused on the removal of dibenzothiophene (DBT) from model diesel oil using CuO-loaded γ-Al2O3–reduced graphene oxide (CuO/γ-Al2O3–RGO) as an adsorbent, which possesses the highest adsorption capacity among reported regenerable graphene-related materials. The boehmite–RGO supports were synthesized using a one-pot hydrothermal synthesis method. As the RGO sheet surfaces are completely covered and isolated by boehmite nanorods formed via hydroxyl condensation of [Al(OH)x](3–x)+ or Al(OH)3 and the −OH of graphene oxide (GO), the specific surface area of boehmite–RGO increased to 378 m2/g, which is 20.8% higher than that of RGO (313 m2/g). CuO/γ-Al2O3–RGO adsorbents with different CuO contents were prepared, and their DBT adsorption desulfurization properties were evaluated. With a 2% mass ratio of CuO to boehmite–RGO, CuO/γ-Al2O3–RGO displays the highest DBT adsorption capacity (6.0 mg S/g) under ambient conditions, which improved by 53.8% in comparison with that of pure RGO (3.9 mg S/g). Moreover, the regeneration of the CuO/γ-Al2O3–RGO adsorbent is much more practical than that of the pure RGO adsorbent.
研究领域:
材料科学
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环境工程
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产品关联
DOI
高影响因子
Journal of Physical Chemistry Letters
·
2024
·
IF 4.8
Xue Zhou,Yueying Chu,Chao Wang,Qiang Wang,Min Hu,Jun Xu,Feng Deng
γ-Al2O3 is a crucial catalyst widely used in industrial alcohol dehydration processes. However, the specific nature of its active sites has remained unclear. In this study, we utilize two-dimensional heteronuclear correlation solid-state nuclear magnetic resonance and density functional theory calculations to uncover the active Al sites on the surface of γ-Al2O3 that facilitate ethanol dehydration. We show the formation of stable pentacoordinated AlV–ethanol complexes upon the adsorption of ethanol on the tetracoordinated AlIV sites. This interaction significantly enhances synergy with adjacent AlV–OH sites, resulting in a marked reduction of the activation energy barrier for ethene production. Furthermore, we reveal an interchange between AlIV and AlV–OH species, allowing hexacoordinated AlVI–OH sites to participate in the dehydration pathway through the migration of ethanol between these coordination sites.
研究领域:
催化化学
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物理化学
·
固态核磁共振光谱
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密度泛函理论
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表面化学
✓ 已验证
DOI
高影响因子
JOURNAL OF COLLOID AND INTERFACE SCIENCE
·
2022
·
IF 9.965
Jin Liu,Hongyu Chen,Chaosheng Zhu,Songfang Han,Jun Li,Sijia She,Xiaoyong Wu
Advanced oxidation processes (AOPs) based on photo-Fenton reaction has been widely used in refractory organic wastewater treatment . However, the mineralization rate and H 2 O 2 utilization in AOPs is relatively low. Herein, a photothermal-assisted photocatalytic-Fenton-like process with CuO x /γ-Al 2 O 3 catalyst was designed to solve the above issues. The utilization rate of H 2 O 2 and mineralization rate of tetracycline hydrochloride (TC) in the 3%-CuO x /γ-Al 2 O 3 /H 2 O 2 /full spectrum light system were significantly increased to 72.0% and 74.3%, respectively, which were ascribed to the synergy of photothermal effect and photocatalytic-Fenton-like reaction. During the simultaneous removal of TC and Cr(VI), the reaction efficiency of 3%-CuO x /γ-Al 2 O 3 /H 2 O 2 /light system was much higher than that of 3%-CuO x /γ-Al 2 O 3 /H 2 O 2 system. In addition, the 3%-CuO x /γ-Al 2 O 3 /H 2 O 2 /light system was not only active in wider pH range (3–9), but also effective in various organic pollutants and Cr(VI) coexisted solutions as well as different water conditions. More importantly, a possible photothermal-assisted photocatalytic-Fenton-like reaction mechanism for the simultaneous removal of TC and Cr(VI) in the CuO x /γ-Al 2 O 3 /H 2 O 2 /light system was proposed. This work may pave a new way for efficient simultaneous removal of refractory organic pollutants and heavy metals in wastewater.
研究领域:
环境科学
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废水处理
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产品关联
DOI
PubMed
高影响因子
CATALYSIS TODAY
·
2022
·
IF 6.562
Peng Bai,Tao Zhou,Xiaohua Wang,Xiaofei Liu,Yi Wang,Yue Wang,Edgar Muhumuza,Yonghui Zhang,Pingping Wu
A series of γ-Al 2 O 3 supported gold-palladium (Au-Pd) alloy nanoparticles (NPs) catalysts were synthesized by a one-pot approach applying mercapto-propyl-trimethoxysilane (MPTMS) as an anchoring ligand. Homogeneously dispersed Au-Pd alloy NPs were observed on the prepared catalysts and their catalytic performance in benzyl alcohol partial oxidation was investigated. Results showed that the highest benzaldehyde yield was achieved on catalyst Au-Pd/7%MPTMS-γ-Al 2 O 3 with a benzaldehyde selectivity of 90%. By establishing the structure-performance relationship, the high activity of catalysts with MPTMS modification was attributed to the anchoring and dispersion effect of MPTMS on Au-Pd NPs, while the high benzaldehyde selectivity was due to the formation of more surface Lewis acid sites after introducing MPTMS, protecting the benzaldehyde from over-oxidation to byproducts.
研究领域:
催化化学
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材料科学
✓ 已验证
产品关联
DOI
高影响因子
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
·
2024
·
IF 8.1
Wenjie Zhang,Jing Zhao,Linfeng Wang,Guofu Liu,Dekui Shen,Huiyan Zhang
The pyrolytic reforming of toluene to hydrogen and CNTs over the commercial and self-prepared Al 2 O 3 loaded with Fe through the impregnation method is investigated in a fixed bed reactor under the temperature from 600 °C to 800 °C. The physicochemical properties of Fe–Al 2 O 3 catalysts and Al 2 O 3 supports were characterized by XPS, H 2 -TPR, HRTEM and H 2 -pulse chemisorption . The reforming process over the catalyst of Fe loaded on self-prepared Al 2 O 3 gives the excellent H 2 yield of 27.8 mmol/(g-Fe) and graphite yield of 82.6 wt%, which is much higher than those from that over the catalyst of Fe loaded on the commercial Al 2 O 3 . It is evidenced by H 2 -pulse chemisorption that 5.1 % of Fe 0+ dispersion over the commercial Al 2 O 3 with mainly-exposed (110) facet while 11.2 % of Fe 0+ dispersion over self-prepared Al 2 O 3 with mainly-exposed (111) facet were obtained. The adsorption energy of iron cluster (Fe 4 ) with Al 2 O 3 (111) facet was estimated to be −14.5 eV through the DFT simulation, which is notably higher than that of iron cluster (Fe 4 ) with Al 2 O 3 (110) facet as −9.1 eV. With regard to the MD simulation along with XRD analysis of the Fe 3 C crystallite , Fe 0+ particles can be prominently molten at the high Fe 0+ dispersion over Al 2 O 3 facet, promoting the carbon solubility for the assembly of multi-wall CNTs without the deposition of unwanted amorphous carbon .
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 THE ENERGY INSTITUTE
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2021
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IF 6.186
Hao Xu,Xing Fan,Guo-Sheng Li,Yang-Yang Xu,Wen-Long Mo,Peter N. Kuznetsov,Feng-Yun Ma,Xian-Yong Wei
Co-Mo/γ-Al 2 O 3 bimetallic catalyst was prepared by incipient wetness impregnation and the physicochemical properties were obtained by a series of characterization methods. The active components are mainly MoS 2 and Co-Mo-S existing on γ-Al 2 O 3 , the support. Meanwhile, the activity of catalyst in hydroconversion of four coal-related model compounds (CRMCs), dibenzyl ether, furan, thiophene and quinoline, was investigated. Hydroconversion products were analyzed by gas chromatography/mass spectrometry (GC/MS) and the possible reaction pathways were proposed according to the GC/MS data. Oxygen was removed from dibenzyl ether via the direct cleavage of C alk -O bridge bond to produce benzylium cation followed by the combination with H − to generate toluene. The hydroconversion of furan can be realized by the direct cleavage of C ar -O bond and direct hydrogenation, respectively. For thiophene, H + directly transferred to sulfur atom, leading to the cleavage of C ar -S bond to produce H 2 S and 1,3-butadiene, which abstracted active hydrogen to yield butane. Another indirect desulfurization pathway for thiophene is hydrogenating to form tetrahydrothiophene and C–S bond cracking to produce butane. Hydroconversion of quinoline started with either N-ring or benzene ring , and the first one was the main pathway.
研究领域:
催化化学
·
煤炭化学
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DOI
高影响因子
Journal of Materials Chemistry A
·
2017
·Vol. 5
·期 14
·6664-6676
·
IF 8.867
Zepei Bao,Lin Ye,Beibei Fang,Lijun Zhao
Herein, Fe0.32Co0.68 binary metal nanoparticles synthesized at room-temperature were loaded onto a novel hierarchical flower-like γ-Al2O3@C composite, which improved the stability and dispersity of the Fe0.32Co0.68 nanoparticles. The freshly prepared Fe0.32Co0.68/γ-Al2O3@C displayed good adsorption of Orange II (100 mg L−1, 973.55 mg g−1). Subsequently, the used Fe0.32Co0.68/γ-Al2O3@C adsorbent (Fe–Co oxide/γ-Al2O3@C) was reused as a peroxymonosulfate (PMS) catalyst. Amazing results were obtained, which demonstrated that Fe–Co oxide/γ-Al2O3@C can highly efficiently decompose Orange II (60 mg L−1, 1 min; 90 mg L−1, 2 min, 120 mg L−1, 7 min and 150 mg L−1, 10 min) as a PMS catalyst. It also exhibited good general degradation of different organic pollutants and excellent reusability (98%, tenth cycle) due to the structural stabilities of γ-Al2O3@C. Further, an experiment was carried out to treat high concentrations of Orange II (200 mg L−1) with the Fe0.32Co0.68/γ-Al2O3@C nanocomposite. After adsorption, PMS was added, and 98% degradation occurred within 5 minutes. The combination of adsorption and PMS advanced oxidation techniques may be one of the effective ways to deal with high-concentration dye wastewater.
研究领域:
环境科学
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材料科学
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产品关联
DOI
高影响因子
JOURNAL OF THE ENERGY INSTITUTE
·
2021
·
IF 6.186
Wenbin Li,Jida Wang,Zhen Wang,Jie Chen,Xiaoan Nie,Zhangshuai Ding,Dechao Wang,Zhifeng Zheng,Yunwu Zheng,Jianchun Jiang
Pt–Sn–Ce/γ-Al 2 O 3 catalysts were synthesized by the impregnation method and used to produce aromatic hydrocarbons (AHs)-rich bio-oil via catalytic fast pyrolysis of cellulose . The upgraded products were on-line analyzed by pyrolysis-comprehensive two-dimensional gas chromatography/mass spectrometry (Py-GC × GC/MS). It was found that Pt–Sn–Ce/γ-Al 2 O 3 catalysts were effective for improving the relative content of AHs in bio-oil. Especially, Pt–Sn–Ce/γ-Al 2 O 3 contributed the highest AHs content (85.82%), which was 3 times than that of γ-Al 2 O 3 , and increased 85.44% compared with non-catalytic. In addition, Pt–Sn–Ce/γ-Al 2 O 3 and Pt–Sn/γ-Al 2 O 3 can generate the highest monocyclic aromatic hydrocarbons (MAHs) with the relative content of 60.24% and 51.92%, respectively. Pt–Sn–Ce/γ-Al 2 O 3 catalyst can be reused five times with stable catalytic activity to produce AHs-rich bio-oil.
研究领域:
能源化学
·
催化材料科学
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产品关联
DOI
高影响因子
CHEMOSPHERE
·
2023
·
IF 8.8
Zilong Zhao,Shuyu Qi,Jianli Zhou,Yatao Ren,Kaiyun Zheng,Jin Zhang,Wenyi Dong,Hongjie Wang
To enhance the polarization distribution of electron cloud density on the catalyst surface, we have introduced a novel bimetallic-substituted dual-reaction center (DRC) catalyst (FeCo-γ-Al 2 O 3 ) comprising iron (Fe) and cobalt (Co) for the decomplexation and mineralization of heavy metal complex Ni-EDTA in this study. Compared to the catalysts doped solely with Fe or Co, the bimetal-doped catalyst offered several advantages, including enhanced electron cloud polarization distribution, additional electron transfer pathway, and improved capacity of free radical generation. Through DFT calculations and EPR tests, we have elucidated the influences of the catalyst's adsorption toward Ni-EDTA and its decomplexation products on the electron transfer between the pollutant and the catalyst. The competition between the pollutants and H 2 O 2 affects the generation of free radicals in both electron-rich Fe and Co centers as well as electron-deficient Al center. Building on these findings, we have proposed a plausible removal mechanism of Ni-EDTA using the heterogeneous Fenton-like catalyst FeCo-γ-Al 2 O 3 . This study sheds light on the potential of FeCo-γ-Al 2 O 3 as a DRC catalyst and emphasizes the significance of pollutant characteristics in determining the catalyst's performance.
研究领域:
环境科学
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材料科学
·
化学工程
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产品关联
DOI
PubMed
高影响因子
ENVIRONMENT INTERNATIONAL
·
2019
·
IF 7.943
Qian Sun,Cun Liu,Peixin Cui,Tingting Fan,Mengqiang Zhu,Marcelo Eduardo Alves,Matthew G. Siebecker,Donald L. Sparks,Tongliang Wu,Wei Li,Dongmei Zhou,Yujun Wang
Apart from surface complexation, precipitation of minerals also plays an important role in reducing the mobility and transport of heavy metals in the environment. In this study, Cd(II) sorption species on surfaces of γ-Al 2 O 3 at pH 7.5 were characterized using multiple techniques. Results show that in addition to adsorption complexes, Cd hydroxide phases (Cd(OH) 2 precipitates and Cd x (OH) y polynuclear complexes) were formed at the initial stages of Cd(II) sorption and gradually transformed to CdCO 3 with time. In addition, Cd(II) formed Cd Al layered double hydroxide (LDH) on γ-Al 2 O 3 under various conditions, independent of temperature and Cd loadings. The formation of Cd hydroxide phases and Cd Al LDH could be ascribed to surface-induced precipitation because the bulk solution was undersaturated with respect to hydroxides. Cd Al LDH formation on the Al-bearing mineral here is rather surprising because typically this occurs with elements of ionic radii similar to that of Al 3+ ; this formation is unknown for metals such as Cd(II) with a much larger ionic radius. The thermodynamic feasibility of Cd Al LDH formation was further confirmed by laboratory synthesis of Cd Al LDH and density function theory (DFT) calculations. These results suggest that Cd precipitation on Al-bearing minerals can be an important mechanism for Cd immobilization in the natural environment. Additionally, the finding of Cd Al LDH formation on Al-bearing minerals and the thermodynamic stability of Cd Al LDH provides new insights into the remediation of Cd-polluted soils and aquatic systems.
研究领域:
环境科学
·
地球化学
·
材料科学
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产品关联
DOI
PubMed
高影响因子
ENERGY CONVERSION AND MANAGEMENT
·
2019
·
IF 7.181
Yujiao Zhang,Shengli Niu,Chunmei Lu,Zhiqiang Gong,Xun Hu
This research focused on the novel, low-cost and green NaAlO 2 /γ-Al 2 O 3 heterogeneous nanocatalyst, which exhibited the excellent performance in catalyzing transesterification of palm oil with methanol for the biodiesel production. The physicochemical properties of the catalysts were characterized by different methods of the X-ray diffraction (XRD), N 2 adsorption–desorption, attenuated total reflectance-Fourier transform infrared spectroscopy (ATR-FTIR), Hammett indicators, field emission scanning electron microscopy-energy dispersive spectrometer (FESEM-EDS) and inductively coupled plasma-optical emission spectrometry (ICP-OES). The transesterification parameters, such as the methanol to oil molar ratio, catalyst content and reaction temperature, were optimized using the central composite design (CCD) based the response surface methodology (RSM), where the maximum biodiesel yield of 97.65% was achieved at the methanol to oil molar ratio of 20.79:1, catalyst content of 10.89 wt% and reaction temperature of 64.72 °C. The biodiesel yield was dropped to 52.16% for the third reused cycle due to the leaching of the active sites into the liquid phase. However, the spent catalyst could be effectively regenerated with a small number of active sites and the regenerated catalyst maintained the biodiesel yield of 93.29% for the sixth reused cycle. The properties of the produced biodiesel were in accordance with the ASTM D 6751 standard. Also, the biodiesel production process was environmental friendly based on the green chemistry metrics.
研究领域:
化学工程
·
可再生能源
·
催化科学
✓ 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）