Journal of Environmental Sciences
·
2022
·
IF 6.796
Xiao Chen,Yong Wang,Jianyu Li,Zhongheng Hu,Ying Zhou,Huayan Liu,Hanfeng Lu
The preparation of highly active supported noble metal catalysts with a low noble metal loading has always been the ultimate goal of researchers working on catalysis. Hydrothermally treated Pt/Al 2 O 3 (Pt/Al 2 O 3 -H) exhibits better catalytic activity than that (Pt/Al 2 O 3 -C) treated via the conventional calcination approach. At the high space velocity of 100,000 mL/(g∙hr), the temperature that correspond to 50% toluene conversion ( T 50 ) of Pt/Al 2 O 3 -H is 115°C lower than that of Pt/Al 2 O 3 -C, and the turnover frequency (TOF) value can reach 0.0756 sec −1 . The mechanism by which the hydrothermal approach enhances Pt/Al 2 O 3 activity has been investigated. The structure associated with the high catalytic activity of Pt nanoparticles (NPs) can be retained via hydrothermal treatment. Furthermore, the support is transformed to AlO(OH) with numerous surface hydroxyl groups, which in turn can facilitate the adsorption of toluene. And the synergistic effects of Pt NPs and AlO(OH) increases the contents of Pt in oxidation state and active oxygen, which are beneficial for toluene oxidation.
研究领域:
催化化学
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环境科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
CHINESE JOURNAL OF CATALYSIS
·
2019
·
IF 4.914
Ziyan Zhao,Dmitry E. Doronkin,Yinghao Ye,Jan-Dierk Grunwaldt,Zeai Huang,Ying Zhou
Light illumination has been widely used to promote activity and selectivity of traditional thermal catalysts. Nevertheless, the role of light irradiation during catalytic reactions is not well understood. In this work, Pt/Al 2 O 3 prepared by wet impregnation was used for photothermal CO 2 hydrogenation, and it showed a photothermal effect. Hence, operando diffuse reflectance infrared Fourier-transform spectroscopy and density functional theory calculations were conducted on Pt/Al 2 O 3 to gain insights into the reaction mechanism. The results indicated that CO desorption from Pt sites including step sites (Pt step ) or/and terrace site (Pt terrace ) is an important step during CO 2 hydrogenation to free the active Pt sites. Notably, visible light illumination and temperature affected the CO desorption in different ways. The calculated adsorption energy of CO on Pt step and Pt terrace sites was −1.24 and −1.43 eV, respectively. Hence, CO is more strongly bound to the Pt step sites. During heating in the dark, CO preferentially desorbs from the Pt terrace site. However, the additional light irradiation facilitates transfer of CO from the Pt step to Pt terrace sites and its subsequent desorption from the Pt terrace sites, thus promoting the CO 2 hydrogenation.
研究领域:
催化化学
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材料科学
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环境科学
✓ 已验证
产品关联
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2024
·
IF 13.3
Jihui Yao,Zhikang Xu,Shuo Cheng,Yuanyuan Yue,Haibo Zhu
The use of dodecahydro- N -ethylcarbazole in hydrogen storage for liquid organic hydrogen carrier systems holds potential for achieving large-scale application. In order to investigate the relationship between dodecahydro- N -ethylcarbazole dehydrogenation performance and Pt particles size, a series of monometallic Pt/Al 2 O 3 catalysts with different Pt particles size from 0.70 nm to 5.12 nm were controlled synthesized by a simple impregnation method. The obtained catalysts are systematically characterized via XRD, 27 Al MAS NMR, SEM-EDS, TEM, N 2 -adsorption, CO-IR, H 2 -TPR and NH 3 -TPD analyses, which provide essential micro-structure of these catalysts. The dehydrogenation of dodecahydro- N -ethylcarbazole over Pt/Al 2 O 3 is a typical consecutive reaction, which follows a reaction sequence of dodecahydro- N -ethylcarbazole → octahydro- N -ethylcarbazole → tetrahydro- N -ethylcarbazole → N -ethylcarbazole. These dehydrogenation steps are quite sensitive to the Pt particle size. Large Pt particle can greatly enhance the reaction rates in octahydro- N -ethylcarbazole → tetrahydro- N -ethylcarbazole and tetrahydro- N -ethylcarbazole → N -ethylcarbazole steps. However, these two steps are difficult to take place in small Pt particles. The high performance of large Pt particle in dehydrogenation can be ascribed to its highly exposed (1 1 1) crystal face. The optimized catalyst Pt 5.0 /γ-Al 2 O 3 with Pt average size of 4.63 nm demonstrated exceptional performance in dodecahydro- N -ethylcarbazole dehydrogenation at 180 °C and 101 kPa, and the dodecahydro- N -ethylcarbazole conversion of 100 %, N -ethylcarbazole selectivity of 96.44 % and dehydrogenation efficiency of 98.73 % can be achieved. These results provide valuable insights for the development of efficient metal-based catalysts for liquid organic hydrogen carriers hydrogen storage system.
研究领域:
催化化学
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能源材料科学
✓ 已验证
产品关联
DOI
高影响因子
ACS Catalysis
·
2020
·
IF 12.35
Yang Chen,Yingxin Feng,Lin Li,Jingyue Liu,Xiaoli Pan,Wei Liu,Fenfei Wei,Yitao Cui,Botao Qiao,Xiucheng Sun,Xiaoyu Li,Jian Lin,Sen Lin,Xiaodong Wang,Tao Zhang
Exclusive Pt species supported on inert substrates have not achieved satisfactory performance for cryogenic CO oxidation because of the constraint of the competitive Langmuir–Hinshelwood process in which the strongly adsorbed CO inhibits the activation of O2. Here, we develop a catalyst of Pt nanoparticles on Al2O3 that exhibits extremely high activity with 100% CO conversion at −20 °C and orders of magnitude higher specific rate than current commercial catalysts. Detailed catalyst characterizations reveal the presence of metallic Pt sites and positively charged ones associated with the OH species in Pt/Al2O3. Both experimental data and theoretical calculations suggest that CO adsorbed on Pt(OH) kink sites reacts with OH species covering Pt0 terrace sites to release CO2. Afterward, O2 is facilely activated on terrace sites to regenerate OH. The presence of OH species and the synergy between Pt kink and terrace sites on the Pt species lead to an ultralow reaction barrier for CO oxidation.
研究领域:
催化化学
·
材料科学
✓ 已验证
DOI
高影响因子
CATALYSIS COMMUNICATIONS
·
2019
·
IF 3.674
Feng Wang,GuoQin Qi,ChuanQi Zhang,HeCheng Ren,Hua Ma,Yu Guo
A series of Na-doped Pt/Al 2 O 3 catalysts with 0.2 wt% of Pt loading and 0–6 wt% Na loading was prepared to investigate the HCHO complete oxidation at room temperature. Powder XRD, BET and XPS were used to characterize the bulk structure and texture of catalysts, as well as the ratio of hydroxyl oxygen to lattice oxygen. A long-term catalyst stability test (50 h on reaction stream) was conducted under severe conditions of a large space velocity of 180,000 mL/h/g, a high HCHO concentration of 80 ppm and dry conditions (relative humidity of 0%). An appropriate amount of doped-Na (2 wt%) contributed to a remarkable improvement of activity and stability of the Na-doped 0.2 wt% Pt/Al 2 O 3 catalyst.
研究领域:
催化化学
·
环境科学
✓ 已验证
产品关联
DOI
高影响因子
INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
·
2025
·
IF 3.9
Chengyin Lin,Yongyuan Deng,Yuankai Lin,Jun Li,Junling Tu,Riyang Shu
Hydrodeoxygenation (HDO) represents a highly efficient refining pathway to convert lignin-derived phenolic compounds for the production of hydrocarbon fuels, and the selection of a suitable catalyst is pivotal for a high reaction efficiency. In this study, we introduce a novel highly dispersed Pt/Al2O3–TiO2 composite catalyst that is prepared via a photochemical reduction method and employ it for the HDO of lignin-derived phenolic compounds. The catalyst demonstrates a good HDO performance, achieving complete conversion of guaiacol at 260 °C with cyclohexane selectivity of 99.9%. Catalyst characterization results reveal that the Pt/Al2O3–TiO2 catalyst exhibits a high Pt metal dispersion. Besides, the composite support synergistically combines the properties of Al2O3 and TiO2 components, resulting in a high specific surface area, moderate acidity, and abundant oxygen vacancy. These factors facilitate the provision of numerous active metal sites and acid sites those are essential for the HDO reaction. Moreover, the Pt/Al2O3–TiO2 catalyst also shows a high activity on the HDO of various other phenolic compounds. When applied to the upgrading of lignin oil, the catalyst significantly increases the hydrocarbon content from 18.9% to 92.2%, concurrently reducing the oxygen content and substantially increasing the hydrogen content of the lignin oil. The calorific value is significantly enhanced, underscoring the potential of the Pt/Al2O3–TiO2 composite catalyst to upgrade lignin-derived phenolic compounds into high-quality hydrocarbon liquid fuels.
研究领域:
催化化学
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可再生能源
✓ 已验证
产品关联
DOI
高影响因子
Molecular Catalysis
·
2025
·
IF 4.9
Shiping Wu,Yanhong Quan,Shunan Yin,Jun Ren
A series of Pt/Al 2 O 3 catalysts were fabricated by finely adjusting the amount of platinum and investigated in the selective oxidative of ethylene glycol (EG) to glycolic acid (GA) under mild neutral conditions. The 0.90Pt/Al 2 O 3 catalyst showed the maximum turnover frequency (TOF: 1106.6 h −1 ) with the EG conversion of 74.2 % and GA selectivity of 90.2 %. A strong linear relationship between TOF values and Pt 0 concentration was revealed, confirming that Pt 0 species serves as the active sites for GA formation. In addition, in situ diffused reflectance infrared Fourier transform spectroscopy (DRIFTS) results verify the reaction pathways of EG oxidation as follows: C 2 H 6 O 2 → HOCH 2 CHO → HOCH 2 COOH. This work unraveled structure-performance relationship for the selective EG oxidation over Pt/Al 2 O 3 catalyst, providing important guidance for the design of efficient noble catalysts especially for the oxidation reaction of polyols.
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
INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
·
2025
·
IF 3.9
Yuan Ma,Baining Lin,Lukai Luo,Chaojun Guo,Le Xie,Yonghua Zhou
The low activity and rapid coke deposition issues are challenging for the nonmetal and metal catalysts in the direct dehydrogenation (DDH) of ethylbenzene to styrene, respectively. To address these issues, the synergistic effect between nonmetal and metal species was explored in this paper by successively loading Pt species and phosphorus oxynitride (PNO) on Al2O3 support to fabricate PNO/Pt/Al2O3 catalyst. The XPS, TEM, NH3-TPD, and CO2-TPD characterizations revealed an obvious strong interaction between Pt and P, increasing the loading amount of PNO and significantly modifying the electronic properties of the Pt species. The catalytic performance results showed that PNO/Pt/Al2O3 not only exhibited higher catalytic activity with XEB of 56.68% than that of PNO/Al2O3 (39.55%) and Pt/Al2O3 (41.65%) but also displayed better coke resistance than Pt/Al2O3 at high-concentration of ethylbenzene feed. DFT calculations confirmed that the interaction between Pt and PNO led to the obviously reduced energy barriers for α-C–H and β-C–H bond breaking, which therefore enhanced the catalytic activity.
研究领域:
化学工程
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催化材料科学
✓ 已验证
产品关联
DOI
高影响因子
Catalysis Science & Technology
·
2024
·Vol. 14
·期 14
·4058-4067
·
IF 4.4
Yang You,Aijie Xu,Yao Lv,Lide Yang,Xuan Tang,Jie Tang,Yanglong Guo,Yao Cui,Wangcheng Zhan,Li Wang,Yun Guo,Sheng Dai
Complete oxidation of propane has drawn great attention in the fields of automotive emission control and volatile organic compound elimination. However, it is challenging to achieve high activity of this reaction due to the stability of propane. We here utilize a facile solvothermal method to construct tri-coordinated Al (AlIII) sites on the as-synthesized ST-Al2O3 support to alter the properties of supported Pt species. It is demonstrated that AlIII sites facilitate the dispersion and electron enrichment of supported Pt sites. Thus, Pt/ST-Al2O3 exhibits a superior activity toward complete propane oxidation, showing a 6.7-fold improvement in the turnover frequency over commercial Pt/Al2O3 catalysts. Meanwhile, Pt/ST-Al2O3 possesses a distinct reaction route originating from its stronger C–H and C–C cleavage capability, while having excellent activity not only in complete propane oxidation but also in the complete oxidation of other alkanes (CH4, C2H6, and n-C4H10). In addition, the AlIII construction strategy is successfully extended to more cases, e.g., Pd/ST-Al2O3 with higher Pd dispersion and electron density. This work provides a promising strategy for the control of the oxide support for advanced design and synthesis of alkane oxidation catalysts.
研究领域:
催化化学
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环境科学
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材料科学
✓ 已验证
产品关联
DOI
高影响因子
ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH
·
2024
·Vol. 31
·期 25
·37746-37756
·
IF 0
Tian You,Han Zhitao,Li Yeshan,Zhao Hongzhe,Zeng Qingliang,Cheng Shaoshi
The selective catalytic oxidation (SCO) is an effective method for removing slipped high-concentration ammonia from NH 3 -fueled engine exhaust gas. Herein a novel bifunctional catalyst was synthesized by mechanically mixing sulfated Ce/ZrO 2 (Ce/ZrO 2 -S) with a small fraction of Pt/Al 2 O 3 (Pt 0.1 wt.%) for SCO of NH 3 . As expected, the introduction of a small amount of Pt/Al 2 O 3 significantly improved NH 3 conversion ability of Ce/ZrO 2 -S catalysts toward low-temperature direction. When the mass ratio of Pt/Al 2 O 3 to Ce/ZrO 2 -S was 7.5% (the corresponding mixed catalyst was denoted as P@CZS-7.5), T 90 temperature was 312 °C. More importantly, P@CZS-7.5 catalyst exhibited a much better N 2 selectivity (> 96%) in a wide temperature range (320 ~ 450 °C). H 2 -TPR results revealed that the addition of a trace amount of Pt/Al 2 O 3 significantly led to a distinct shift of reduction temperature peak toward low-temperature direction, thereby greatly improved the low-temperature redox performance of mixed catalysts. Furthermore, NH 3 -TPD and BET results showed that P@CZS-7.5 catalyst exhibited a similar NH 3 adsorption capacity to Ce/ZrO 2 -S catalyst, while the former had a relatively higher specific surface area than the latter. It was considered as a crucial factor for P@CZS-7.5 catalyst maintaining superior N 2 selectivity in high-concentration NH 3 (5000 ppm) removal processes. In situ DRIFTS results indicated that P@CZS-7.5 catalyst followed the internal selective catalytic reduction (i-SCR) mechanism in NH 3 -SCO reactions.
研究领域:
催化化学
·
环境科学
✓ 已验证
DOI
APPLIED CATALYSIS B-ENVIRONMENTAL
·
2025
·
IF 21.1
Chunxue Wang,Zhao Li,Junjun Qiu,Xin Sun,Yixing Ma,Chi Wang,Kunlin Li,Ping Ning,Kai Li,Fei Wang
In various industrial processes, particularly iron ore sintering operations, the concurrent use of fossil fuels and selective catalytic reduction by ammonia (NH 3 -SCR) denitrification technology inevitably results in the coexistence of carbon monoxide (CO) and escaped NH 3 in the exhaust gases. While simultaneous catalytic oxidation of CO and NH 3 represents an ideal strategy, it encounters significant challenges due to competition for active centers. Moreover, NH 3 -selective catalytic oxidation (NH 3 -SCO) is potentially inhibited by high CO concentrations. In this investigation, we synthesized a series of Pt/Al-X catalysts (X indicating calcination temperature) that demonstrated inverse activity patterns in independent NH 3 -SCO and CO oxidation reactions. Comprehensive analysis incorporating oxygen activation capacity, reactant adsorption characteristics, reaction kinetics, and in situ diffuse reflection infrared Fourier transform spectrum (DRIFTS) measurements indicated that O 2 activation capacity functioned as the rate-determining factor for NH 3 -SCO, whereas CO adsorption capacity and OH group density predominantly governed CO oxidation. Building on these findings, we engineered a composite catalyst by integrating Pt/Al-600 and Pt/Al-900 catalysts. This novel composite effectively reduced active center competition through strategic combination of functional sites, thereby achieving superior performance in simultaneous CO and NH 3 removal, while maintaining excellent water resistance and operational stability.
研究领域:
环境科学
·
催化化学
✓ 已验证
产品关联
DOI
高影响因子
FUEL
·
2025
·
IF 7.5
Chen-Xu Chen,Jing-Pei Cao,Nai-Yu Yao,Wen Tang,Wei Jiang,Chuang Zhang,Xiao-Yan Zhao,Xiao-Yu Qiao,Tungalagtamir Bold
Improving the catalytic efficiency and catalyst life of Pt/Al 2 O 3 catalyst for methylcyclohexane dehydrogenation is of great significance for the study of organic liquid hydrogen storage. In this work, the promotion effects of Ga and Ce on the substantial improvement of catalytic stability and activity over the Pt / Al 2 O 3 during the methylcyclohexane dehydrogenation were investigated. The catalyst with optimizing Ga and Ce loading (1.5 wt%) exhibits ∼99.76 % selectivity and H 2 evolution rate of 2102 mol/g Pt /min at 300 °C. In 100 h long-time reaction, the conversion of methylcyclohexane remains around 75 % with no significant decrease. The characterization results show that introducing proper amount of Ga and Ce helps Ga 3+ cations incorporate into the lattice structure of CeO 2 that increase concentration of oxygen vacancies and CeO 2 reducibility in the catalyst, which boost the capability of methylcyclohexane dehydrogenation and tolerance for coke formation. Thus, the excellent stability and activity are achieved over the GaCe-modified catalyst. This study may share new light on the rational construction of highly efficient Pt-based catalysts for methylcyclohexane dehydrogenation.
研究领域:
催化化学
·
能源材料
·
表面科学
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纳米催化
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氢储能
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材料化学
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）