SEPARATION AND PURIFICATION TECHNOLOGY
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2022
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IF 9.136
Sitan Wang,Xuan Meng,Naiwang Liu,Li Shi
Sulfated zirconia, as a promising catalyst in various acid-catalytic reactions, still suffer from unsatisfactory catalytic stability and regeneration performance due to severe leaching of sulfur species, while aluminum modification can effectively overcome these drawbacks. Unfortunately, the limited acceptability of aluminum content by co-precipitation and milling methods remains a critical issue. Herein, an effective strategy of coating sulfated zirconia on the surface of γ-Al 2 O 3 was developed to synthesize the novel Al 2 O 3 @SO 4 2- /ZrO 2 catalyst with high aluminum content. The synthesis variables were investigated and systematically optimized. The structural and acidic properties of Al 2 O 3 @SO 4 2- /ZrO 2 were determined by XRD, HR-TEM equipped with EDX, N 2 adsorption-desorption isotherms, EA, FT-IR, NH 3 -TPD and Py-FTIR. Results indicated that the unique structure constructed by sulfated zirconia coated on γ-Al 2 O 3 not only realized the stabilization of favorable tetragonal zirconia phase even at exceedingly high aluminum content but also promoted Brønsted acid sites. Accordingly, the optimal Al 2 O 3 @SO 4 2- /ZrO 2 - 50% performed outstanding catalytic activity and stability, given the olefins conversion of 98%-75% during the continuous reaction experiment. Owing to the alleviation of sulfur loss by Al-promoting effects, excellent regeneration performance, with olefins conversion only slightly declining after 4 consecutive reaction-regeneration cycles, was also obtained. The mechanistic pathway for the alkylation of olefins with aromatics over Al 2 O 3 @SO 4 2- /ZrO 2 was also investigated and proposed by GC–MS analysis.
研究领域:
催化
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化学工程
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材料科学
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DOI
高影响因子
Nature Communications
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2020
·Vol. 11
·期 1
·1-11
·
IF 12.121
Gao Shaojie,Hao Shaoyun,Huang Zhennan,Yuan Yifei,Han Song,Lei Lecheng,Zhang Xingwang,Shahbazian-Yassar Reza,Lu Jun
High-entropy alloy nanoparticles (HEA-NPs) are important class of materials with significant technological potential. However, the strategies for synthesizing uniformly dispersed HEA-NPs on granular supports such as carbon materials, γ-Al 2 O 3 , and zeolite, which is vital to their practical applications, are largely unexplored. Herein, we present a fast moving bed pyrolysis strategy to immobilize HEA-NPs on granular supports with a narrow size distribution of 2 nm up to denary (MnCoNiCuRhPdSnIrPtAu) HEA-NPs at 923 K. Fast moving bed pyrolysis strategy ensures the mixed metal precursors rapidly and simultaneously pyrolyzed at high temperatures, resulting in nuclei with a small size. The representative quinary (FeCoPdIrPt) HEA-NPs exhibit high stability (150 h) toward hydrogen evolution reaction with high mass activity, which is 26 times higher than the commercial Pt/C at an overpotential of 100 mV. Our strategy provides an improved methodology for synthesizing HEA-NPs on various supports.
研究领域:
材料科学
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纳米技术
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催化
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DOI
PubMed
高影响因子
OZONE-SCIENCE & ENGINEERING
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2019
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IF 1.253
Wencan Qi,Jing Wang,Xie Quan,Shuo Chen,Hongtao Yu
Heterogeneous catalytic ozonation is an efficient technology for degrading refractory organic pollutants in water. However, most studied heterogeneous catalysts for catalytic ozonation were powders, which were not practically available for continuous fixed-bed reactor in water treatment. In this work, manganese, iron and cerium oxides on γ-Al2O3 pellets were synthesized and used as heterogeneous catalysts for catalytic ozonation in a continuous fixed-bed reactor. Results showed that all the prepared metal oxides on γ-Al2O3 pellets exhibited facilitated catalytic ozonation for degrading refractory contaminates compared with ozonation alone and catalytic ozonation on pure γ-Al2O3 pellets. The cerium oxides supported on γ-Al2O3 pellets (CeO2/γ-Al2O3) performed best catalytic performance with the COD removal efficiency of 64.3% and TOC removal efficiency of 41.7%. Moreover, the catalytic activity was further enhanced by the synergistic effect of the bimetallic oxides on γ-Al2O3 pellets (CeO2-Fe2O3/γ-Al2O3). This study is expected to help to encourage further research and applications in AOPs based on the success of this work in designing heterogeneous catalysts available for continuous fixed-bed reactor.
研究领域:
环境科学
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化学工程
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水处理
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高级氧化技术（AOPs）
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DOI
高影响因子
CATALYSIS COMMUNICATIONS
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2017
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IF 3.33
Fei Chen,Feng Wang,Qing Li,CaiYuan Cao,Xiang Zhang,Hua Ma,Yu Guo
Different catalyst supports, namely: commercial Degussa P25 TiO 2 , anatase TiO 2 (CC), γ-Al 2 O 3 , and lab-synthesized AlOOH were used to prepare Pt-based catalysts for the room temperature formaldehyde oxidation. XRD, BET and XPS were conducted to characterize the bulk structure of support, the oxidation state of surface elements and the ratio of oxygen in hydroxyls to the total surface oxygen, as well as textural properties of catalysts. For the first time, a long-term activity test at 0% relative humidity was conducted to investigate relationships between the activity of the Pt-based catalysts with Pt dispersion and oxidation state and the relative abundance of surface OH groups. Pt/AlOOH showed the best activity, whereas Pt/P25 TiO 2 gave the worst activity. We consider that both the surface hydroxyl groups and the Pt dispersion are indispensable, and both act synergistically. The specific surface area is not the decisive factor for the present reaction.
研究领域:
催化化学
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环境催化
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材料化学
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表面科学
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大气污染控制
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DOI
高影响因子
Molecular Catalysis
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2023
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IF 4.6
Shiwei Feng,Chengping Zhang,Hengdao Quan
As an environmentally friendly cleaning agent, Z -1-chloro-3,3,3-trifluoropropene (HCFO-1233zd( Z )) can realize industrial production by the isomerization of HCFO-1233zd( E ). Herein, various isomerization catalysts with different structures, compositions and acid properties were prepared through the fluorination of γ-Al 2 O 3 with CHF 3 by controlling the activation conditions. For the first time, the catalysts for HCFO-1233zd( E ) isomerization were systematically studied by XRD, N 2 physisorption, XPS, SEM, MAS NMR spectroscopy, NH 3 -TPD and py-IR. The active site of this reaction was revealed and the catalyst deactivation mechanism was proposed. It turned out that HCFO-1233zd( E ) isomerization prefers to occur at Lewis acid sites with moderate density and strength. The amorphous particles composed of γ-Al 2 O 3 , Al 2 O 3 (F) and α-AlF 3 ( R 3 ¯ c ) at 450 °C exhibit highly catalytic activity for HCFO-1233zd( E ) isomerization. After 100 h evaluation, it was found that residual γ-Al 2 O 3 can be fluorinated by HCFO-1233zd( E ) to form needle-like structures which could induce the amorphous Al 2 O 3 (F) particles to reorganize and give cubic structures, where the Lewis acid properties were enhanced, leading to catalyst deactivation.
研究领域:
催化
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化学工程
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材料科学
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环境化学
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产品关联
DOI
高影响因子
Molecular Catalysis
·
2024
·
IF 3.9
Xuchao Cui,Jiakang Zhang,Hong-Yu Zhang,Yuecheng Zhang,Jiquan Zhao
ABSTRACT Hexamethylenediamine (HMDA), which is a crucial intermediate for the production of polyamides and other chemical products, was synthesized from the reductive amination of 6-hydroxycapronitrile (6-HHN) derived from ε‑caprolactone (ε‑CPL) with aqueous ammonia as the ammonia source. A bimetallic catalyst Co 10 Ru 1 /MgO-γ-Al 2 O 3(0.3:1) -500 was found to be effective in the reaction. Over this catalyst the conversion of 6-HHN reached up to 100 %, with a HMDA selectivity of 38.14 %, corresponding to a yield of 38.14 %, and the total selectivity of HMDA, 6-amino-1-hexanol (AHO) and hexamethyleneimine (HMI) of 86.92 %. Characterization results disclosed that Co and Ru uniformly disperse on the surface of the MgO-Al 2 O 3 mixed-oxide support, and respectively acts as the dehydrogenation-hydrogenation active species in the reaction with seldom agglomeration either in catalytic run or regeneration process. It was also found that some nonvolatile carbonaceous substances deposited on the surfaces of the catalyst during a catalytic run, leading to the deactivation of the catalyst. The catalysis of the catalyst could be largely recovered by high temperature calcination to remove the carbon deposits, followed by reduction with H 2 .
研究领域:
化学工程
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有机化学
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催化
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DOI
高影响因子
FUEL
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2021
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IF 6.609
Xinyue Zhang,Bo Zhang,Yanjun Chen,Lei Li,Houxiang Sun,Xuandong Liu,Rong Guo,Bo Meng,Peng Liu,Weiyu Song,Qiaoxia Guo,Baojian Shen
Electronic structure tuning is an effective strategy to activate transition metals. In this study, silica-promoted γ-Al 2 O 3 -supported Fe-based hydrodesulfurization catalysts of Fe species with electron loss were successfully prepared by transferring electrons from Fe to Si. The characterization results showed that the Fe-based hydrodesulfurization catalyst with the addition of silica modulated the structure and properties of the active metal, which not only improved the degree of sulfidation of the active metal but also promoted the generation of Fe(III)-S. The hydrodesulfurization rate of dibenzothiophene showed a remarkable rise from 38.4 to 83.2% at 673 K. Importantly, the formation of Fe(III)-S greatly stretched the bond length of Fe-S bonds, exhibiting an increase of approximately 21%, this facilitating the generation of coordinatively unsaturated active site. Finally, the HDS reaction performance of the Fe-based hydrodesulfurization catalysts was mainly influenced by the Fe(III)-S/Fe(II)-S ratio, with the most significant enhancement in the direct desulfurization reaction path. The results of this study provide a promising approach for the design and development of environmentally friendly and economical Fe-based catalysts in the field of clean fuels.
研究领域:
催化
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化学工程
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材料科学
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环境化学
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DOI
高影响因子
Catalysts
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2018
·Vol. 8
·期 12
·642
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IF 3.465
Yan Gao,Tao Luan,Mingyang Zhang,Wenke Zhang,Wenchen Feng
A series of Mn−Fe−Ce−Ox/γ-Al2O3nanocatalysts were synthesized with different Mn/Fe ratios for the catalytic oxidation of NO into NO2and the catalytic elimination of NOxvia fast selective catalytic reduction (SCR) reaction. The effects of Mn/Fe ratio on the physicochemical properties of the samples were analyzed by means of various techniques including N2adsorption, scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), H2-temperature-programmed reduction (TPR), NH3-temperature-programmed desorption (TPD) and NO-TPD, meanwhile, their catalytic performance was also evaluated and compared. Multiple characterizations revealed that the catalytic performance was highly dependent on the phase composition. The Mn15Fe15−Ce/Al sample with the Mn/Fe molar ratio of 1.0 presented the optimal structure characteristic among all tested samples, with the largest surface area, increased active components distributions, the reduced crystallinity and diminished particle sizes. In the meantime, the ratios of Mn4+/Mnn+, Fe2+/Fen+and Ce3+/Cen+in Mn15Fe15−Ce/Al samples were improved, which could enhance the redox capacity and increase the quantity of chemisorbed oxygen and oxygen vacancy, thus facilitating NO oxidation into NO2and eventually promoting the fast SCR reaction. In accord with the structure results, the Mn15Fe15−Ce/Al sample exhibited the highest NO oxidation rate of 64.2% at 350 °C and the broadest temperature window of 75–350 °C with the NOxconversion >90%. Based on the structure–activity relationship discussion, the catalytic mechanism over the Mn−Fe−Ce ternary components supported byγ-Al2O3were proposed. Overall, it was believed that the optimization of Mn/Fe ratio in Mn−Fe−Ce/Al nanocatalyst was an extremely effective method to improve the structure–activity relationships for NO pre-oxidation and the fast SCR reaction.
研究领域:
环境科学
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催化化学
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DOI
高影响因子
CHINESE JOURNAL OF CHEMICAL ENGINEERING
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2026
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IF 3.5
Zhen Xu,Caiyun Wang,Jiling Guo,Tianyu Bai,Yunmei Zhang,Han Yang,Fan Shao,Fengzhi Guo,Wenbin Huang,Qiang Wei
Cerium modification modulates the surface acidity and metal-support interactions of the Ni/γ-Al 2 O 3 catalyst. • Cerium species can not only suppress the formation of strong acid sites, but also regulate the adsorption configuration of pyridine molecules. • The enhanced electron transfer from cerium to nickel improves the reducibility and hydrogen activation performance of nickel. • The Ni/Al–Ce(10) catalyst achieves high catalytic activity in the pyridine hydrogenation reaction. To address the key challenge of achieving both high conversion and high selectivity in the selective hydrogenation of pyridine, this paper proposes a strategy of precisely modulating the surface acidity and metal–support interaction of an alumina support via cerium (Ce) modification. The study shows that Ce modification effectively suppresses the strong acid sites on the alumina surface, thereby promoting the desorption of the target product, piperidine. Meanwhile, Ce doping induces a flat-lying adsorption configuration of pyridine molecules, which is more favorable for the saturation hydrogenation of the aromatic ring, significantly enhancing the hydrogenation selectivity. Ce species facilitate electron transfer to the nickel active centers, increasing the local electron density around the nickel sites. This reduces the binding energy of nickel, enhances its reducibility, and effectively inhibits the formation of nickel aluminate spinel (NiAl 2 O 4 ), thereby improving the intrinsic hydrogenation activity of the catalyst. Under the reaction condition of 200 °C, the Ni/Al–Ce (10) catalyst achieves a pyridine conversion of 99.5% and a piperidine selectivity of 97.4%. Download: Download high-res image (281KB) Download: Download full-size image
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DOI
高影响因子
JOURNAL OF HAZARDOUS MATERIALS
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2025
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IF 11.3
Qiuyu Chen,Yongyi Zhang,Haiwang Liu,Peng Liu,Xinxin Ye,Xing Xia,Xiangwei Wu
Straw-derived dissolved organic matter (DOM) is widespread in farmland soils, but the relationship between straw-derived DOM and As in their co-sorption on minerals and the underlying mechanisms remain unclear. Here, batch experiments and spectroscopic analyses were employed to investigate the co-sorption of straw-derived DOM and As(III/V) on γ-Al 2 O 3 . Results showed a trade-off between the As(III/V) and DOM immobilization on γ-Al 2 O 3 under different pH levels, which was caused by competitive sorption. The rape straw-derived DOM (DOM_Ra) exhibited a stronger inhibition on As(III/V) sorption than rice straw-derived DOM (DOM_Ri). This could be due to more aromatic fractions in the DOM_Ra and DOM_Ri, which were preferentially sorbed by γ-Al 2 O 3 . In turn, the preferential sorption of aromatic DOM components was weakened by As(V) sorption, which, however, was not found in As(III) and DOM co-sorption. Furthermore, spectral results indicated that carboxylic groups on the sorbed DOM could provide additional binding sites for As(III/V) to form ternary complexes, but its role was overwhelmed by the DOM competitive sorption, which ultimately exhibited the inhibitory effect of DOM on As(III/V) sorption. These findings enhance the fundamental understanding of the co-sorption of As(III/V) and DOM on soil minerals and contribute to predicting As mobility and OM stability in As-contaminated farmlands with straw return.
研究领域:
环境科学
·
土壤化学
·
农业生态学
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产品关联
DOI
PubMed
高影响因子
WATER SCIENCE AND TECHNOLOGY
·
2020
·Vol. 83
·期 2
·257-270
·
IF 1.638
Qu Guangzhou,Wang Hui,Li Xin,Wang Tiecheng,Zhang Zengqiang,Liang Dongli,Qiang Hong
This paper presents a study of V and N co-doping TiO 2 embedding multi-walled carbon nanotubes (MWCNTs) supported on γ -Al 2 O 3 pellet (V/N-TiO 2 -MWCNTs/ γ -Al 2 O 3 ) composite photocatalyst induced by pulsed discharge plasma to enhance the removal of acid orange II (AO7) from aqueous solution. The photocatalytic activity of the V/N-TiO 2 -MWCNTs/ γ -Al 2 O 3 composite to AO7 removal induced by the pulsed discharge plasma was evaluated. The results indicate that the V/N-TiO 2 -MWCNTs/ γ -Al 2 O 3 composite possesses enhanced photocatalytic activity that facilitates the removal of AO7 compared with the TiO 2 -MWCNTs/ γ -Al 2 O 3 and TiO 2 / γ -Al 2 O 3 composites. Almost 100% of AO7 is removed after 10 min under optimal conditions. The V 0.10 /N 0.05 -TiO 2 -MWCNTs/ γ -Al 2 O 3 photocatalyst exhibits the best removal effect for AO7. Analysis of the removal mechanism indicates that the enhancement of the removal of AO7 resulting from V and N co-doping causes TiO 2 lattice distortion and introduces a new impurity energy level, which not only reduces the band gap of TiO 2 but also inhibits the recombination of the pairs. An efficient and easily recycled V/N-MWCNTs-TiO 2 / γ-Al 2 O 3 composite was prepared. Activity of the composite induced by discharge plasma to AO7 removal was evaluated. Synergistic effect of discharge plasma and catalyst effectively improve AO7 removal. The composite demonstrates adequate recycling performance in a discharge plasma system. Possible mechanisms of AO7 removal were analyzed.
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DOI
高影响因子
ACS Sustainable Chemistry & Engineering
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2026
·
IF 7.6
Liu Mengyu,Feng Wenji,Wu Yunshuo,Wang Haiqiang,Wu Zhongbiao
Methane valorization is important for climate change mitigation and sustainable carbon utilization, but conventional nonoxidative coupling of methane (NOCM) suffers from the high activation barrier of CH 4 , limited product selectivity, and rapid coking-induced deactivation. Herein, we develop a spark discharge−dielectric barrier discharge (DBD) coupled plasma-catalytic system for the selective conversion of high-concentration methane to ethylene. Spark discharge first activates CH 4 and preferentially converts it to C 2 H 2 , while a downstream catalyst bed, maintained at 100−130 ° C by residual discharge heat, enables acetylene semihydrogenation to C 2 H 4 . A coupled DBD unit is further introduced for in situ carbon removal and catalyst regeneration. Among the tested catalysts, impregnation−reduction-derived 0.1Pd-5Cu/γ-Al 2 O 3 -R with atomically dispersed Pd exhibited the best performance, achieving 72.38% CH 4 conversion, 72.19% C 2 H 4 selectivity, 92.48% acetylene-based C 2 H 4 selectivity, and a C 2 H 4 space-time yield of 69.97 mmol·g· −1 ·h −1 at 36.2 kJ·L −1 . With DBD-assisted regeneration, efficient NOCM operation was maintained for 630 min. Mechanistic analyses associate the enhanced ethylene selectivity with highly dispersed Pd sites and their electronic modulation by predominantly low-valent Cu species, which suppress overhydrogenation and facilitate ethylene desorption.
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DOI
高影响因子
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