INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
·
2020
·
IF 3.573
Jun Jiang,Teng Li,Kexin Huang,Guangyu Sun,Jing Zheng,Jinlong Chen,Weiran Yang
As a bio-based platform chemical, it is desirable to convert levulinic acid (LA) to varieties of value-added biochemicals. n-Butane, mainly from nonrenewable fossil resources, is a basic chemical to produce some important chemicals, such as butadiene and ethylene. In this paper, 95.5% yield of n-butane was obtained from LA in one-step over base-treated Pt/C at around 300 °C in 4 h. The reaction pathway was confirmed to be the hydrodeoxygenation of LA to valeric acid (VA) and then the VA decarboxylation to n-butane by kinetic studies. Base-treated Pt/C had better reactivity due to its improved decarboxylation activity. Detailed characterization of the catalyst revealed that the Pt particle size is the key reason for the activity improvement, and further studies showed that Pt nanoparticles with a size of 2–4 nm showed the highest decarboxylation activity. This is the first report on the direct conversion of LA to n-butane.
研究领域:
化学工程
·
可再生资源
·
催化科学
✓ 已验证
DOI
高影响因子
INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
·
2025
·
IF 3.9
Xuying Liu,Min Zou,Yehao Yu,Yuanrui Hai,Jinyan Huang,Yunchang Fan,Yulong Zhang,Yujing Weng,Yuhe Liao
Glycolic acid (GA), a versatile compound widely used in pharmaceuticals, cosmetics, and biodegradable polymers, requires efficient and sustainable synthesis methods to meet industrial demands. This study investigates the selective oxidation of glycolaldehyde (GD) and ethylene glycol (EG) to GA over a carbon-supported platinum (Pt/C) catalyst under alkali-free conditions. Complete GD conversion with exceptional GA selectivity (99.8%) was achieved under mild conditions (30 °C, 2.5 MPa air), while EG oxidation exhibited moderate conversion (∼60%) with >90% GA selectivity. Kinetic analysis revealed distinct oxygen pressure dependencies: GD oxidation exhibited strong oxygen sensitivity, as oxygen adsorption and activation were rate-determining, whereas EG oxidation was predominantly governed by substrate concentration due to the oxygen saturation on the Pt/C surface. Mechanistic studies identified GD as a key intermediate in EG oxidation, with overoxidation pathways limiting GA selectivity at higher temperatures and concentrations. Catalyst characterization demonstrated high Pt dispersion, stable surface chemistry, and structural durability, contributing to its superior performance. This work provides a green, efficient pathway for GA production, offering valuable insights into catalyst design and process optimization for sustainable chemical manufacturing.
研究领域:
化学工程
·
催化科学
✓ 已验证
产品关联
DOI
高影响因子
CHEMISTRY-A EUROPEAN JOURNAL
·
2016
·Vol. 22
·期 29
·9909-9913
·
IF 5.771
Wenhai Wang,Jing Geng,Long Kuai,Min Li,Baoyou Geng
Graphical Low cost, high value : An Mn 2 O 3 catalyst with porous structure exhibits comparably activity to commercial Pt/C and notably higher activity than other Mn-based oxides, such as Mn 3 O 4 and MnO 2 . In light of the low cost and high earth abundance of Mn, the highly active Mn 2 O 3 is a promising candidate to be used as a cathode material in metal–air batteries and alkaline fuel cells. Preparing nonprecious metal catalysts with high activity in the oxygen reduction reaction (ORR) can promote the development of energy conversion devices. Support-free porous Mn 2 O 3 was synthesized by a facile aerosol-spray-assisted approach (ASAA) and subsequent thermal treatment, and exhibited ORR activity that is comparable to commercial Pt/C The catalyst also exhibits notably higher activity than other Mn-based oxides, such as Mn 3 O 4 and MnO 2 . The rotating ring disk electrode (RRDE) study indicates a typical 4-electron ORR pathway on Mn 2 O 3 . Furthermore, the porous Mn 2 O 3 demonstrates considerable stability and a good methanol tolerance in alkaline media. In light of the low cost and high earth abundance of Mn, the highly active Mn 2 O 3 is a promising candidate to be used as a cathode material in metal–air batteries and alkaline fuel cells.
研究领域:
材料科学
·
电化学
·
能源转换技术
✓ 已验证
DOI
高影响因子
Biomass Conversion and Biorefinery
·
2024
·
IF 3.5
Yang Mingzhu,Li Liangli,Shi Jingjing,Xia Haian,Xu Junming
Lignin is an important source of biomass energy and chemical raw material. The combination of lignin depolymerization and electrocatalytic hydrogenation (ECH) is a very important pathway to convert lignin to high-value chemicals or bio-fuels, which has important economic and environmental significance. It remains great challenges to control the conversion pathways and modulate the desired product selectivity. In additions, in-depth understanding of the hydrodeoxygenation mechanism of lignin pyrolysis oil in ECH has not yet been revealed. Herein, we report the results of ECH of various typical lignin models using Pt/C in a fluid electrocatalytic system. Common phenolic model compounds with different functional groups and varying chain lengths were chosen as the reaction substrates, such as guaiacol, 2,6-dimethoxyphenol, eugenol, phenol, vanillin. The effects of the types and positions of functional groups such as hydroxyl, methoxyl and alkyl groups on the ECH performances were investigated. The electrolytic hydrogenation system employed phosphotungstic acid (PW12) and phosphoric acid as the electrolyte, NaBH 4 as a partial hydrogen source and PW12 reducing agent, and Pt/C as the catalyst directly added to the electrolyte. Results demonstrated that the production of cyclohexane from the ECH of the phenolic model compounds, which have undergone complete deoxygenation. For phenolic compounds containing alkyl substituents, the conversion decreases with increasing chain length, but the selectivity of alkyl cyclohexane increases. These findings contribute to advancing the understanding of lignin utilization and pave the way for sustainable development and energy transformation.
研究领域:
生物质化学
·
催化化学
·
可再生能源
✓ 已验证
产品关联
DOI
高影响因子
RSC Advances
·
2016
·Vol. 6
·期 31
·25877-25881
·
IF 3.289
Ling Li,Mingkun Wang,Ning Cui,Yuedi Ding,Qingling Feng,Wenming Zhang,Xiaowei Li
Incorporation of nanophase ceria into the cathode catalyst Pt/C was used as alternative cathode catalysts for the oxygen reduction reaction in an air-cathode single-chamber microbial fuel cell (SCMFC) for the first time. Electrochemical results reveal that the ceria doped Pt/C catalysts exhibited a higher catalytic performance than the pure Pt/C catalyst. The highest voltage of 580 mV and the maximum power density of 840 ± 24 mW m−2 were achieved from the 3 wt% CeO2 doped Pt/C cathode, which was larger than that of the pure Pt/C cathode.
研究领域:
环境科学
·
电化学
·
能源材料
✓ 已验证
产品关联
DOI
高影响因子
ENERGY & FUELS
·
2017
·
IF 3.091
Qiurong Tian,Zihao Zhang,Feng Zhou,Kequan Chen,Jie Fu,Xiuyang Lu,Pingkai Ouyang
The role of solvents in the conversion of oleic acid over Pt/C was studied. Three solvent systems (solvent-free, water, and dodecane systems) were employed for the conversion of oleic acid over Pt/C at 350 °C. Decarboxylation, hydrogen transfer, and aromatization were observed in these three reaction systems. In comparison to the non-solvent reaction system, much slower decarboxylation and aromatization rates and fewer heptadecane and aromatic products were observed in the hydrothermal and dodecane reaction systems. The decarboxylation and aromatization rates and yields of heptadecane and aromatics decreased with increased dodecane loading in the dodecane reaction system, and the decarboxylation and aromatization rates and yields of heptadecane and aromatics significantly decreased with the increase of water in the hydrothermal reaction system. The effects of solvent loading, catalyst loading, and reaction time on the reactions (decarboxylation, hydrogen transfer, and aromatization) were investigated. The reaction behaviors of 1-heptadecene with different solvents were studied, and N2 adsorption–desorption and thermogravimetric analysis of fresh and spent Pt/C in the three reaction systems were also performed. The results indicate that the competition of dodecane for the Pt/C active sites is mainly responsible for the slow decarboxylation and aromatization rates. In addition to the similar influencing factor to that in the dodecane system, H+ released from water and hydrogen bonding, which inhibited the ionization of carboxyl groups, was the key influencing factor for the slower decarboxylation and aromatization rates obtained under hydrothermal conditions.
研究领域:
化学工程
·
催化科学
✓ 已验证
DOI
高影响因子
Advanced Sustainable Systems
·
2020
·Vol. 4
·期 7
·2000065
·
IF 4.869
Wenrui Yan,Yan Xiang,Jin Zhang,Shanfu Lu,San Ping Jiang
Development of direct formic acid fuel cell (DFAFC) is significantly constrained by low output performance and poor durability because of the sluggish formic acid oxidation reaction (FAOR) and the poisoning by CO ads intermediate on the Pt-based electrocatalyst at low operating temperatures. By operating DFAFCs at elevated temperatures, the peak power density (PPD) of the cell based on the Pt/C catalyst increases significantly. For example, the PPD of DFAFC reaches 198 mW cm −2 at 240 °C, eight times higher than that of the DFAFC at 70 °C. The study shows the surprising transition in power performance of DFAFCs at elevated temperatures. The increase of PPD for DFAFC against temperature is 121 mW cm −2 /100 °C at temperatures above 115 °C, almost three times higher than the 45 mW cm −2 /100 °C obtained at lower temperatures. The fundamental reason for the substantially enhanced power output and durability is the gradual transformation of the reaction kinetics from sluggish direct FAOR at low temperatures to fast H 2 oxidation reaction at elevated temperatures due to the increased in situ decomposition of formic acid on Pt/C catalysts at temperatures above 100 °C. This study demonstrates that operation at temperatures above 160 °C is most effective to promote performance and durability of DFAFCs.
研究领域:
能源科学
·
电化学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF THE ENERGY INSTITUTE
·
2016
·
IF 1
Nan Li,Wei-Yan Xia,Chang-Wei Xu,Shuang Chen
This study investigated Pt/C and Pd/C catalysts promoted by Au for glycerol electrooxidation in alkaline medium . The results show that addition of Au can significantly promote the catalytic activity and stability of Pt/C and Pd/C for glycerol electrooxidation. The catalysts with a weight ratio of 4:1 for Pt to Au and Pd to Au show the best performance for glycerol electrooxidation and the PtAu(wt 4:1)/C shows a better performance than the PdAu(wt 4:1)/C. Glycerol electrooxidation on the PdAu(wt 4:1)/C has a better stability than that on the Pt/C. The results show that the PdAu(wt 4:1)/C can give a better discharge performance than the Pt/C in a direct glycerol fuel cell. Electrooxidation of pre-adsorbed CO has been used to explain the results.
研究领域:
化学
·
催化科学
·
能源材料
✓ 已验证
产品关联
DOI
高影响因子
FUEL
·
2023
·
IF 7.4
Xiaoying Qi,Na Ye,Riguang Zhang,Zhao Jiang,Tao Fang
Developing the efficient and high CO tolerance electrocatalysts is important for methanol oxidation reaction. In this study, a sequence of catalysts were constructed by introducting various transition metal nitrides (TMNs) to modify the Pt/C catalyst. The corresponding electrochemical performance were evaluated to investigate the activity, kinetics, charge transfer rate, CO tolerance and stability for MOR in alkaline media. Based on the structural characterization analysis from ICP-MS, XRD, HRTEM and XPS, it could be indicated that the participation of TMNs mainly brought the electronic effect, but not for the geometric effect. The evident difference did not exist in the nanoparticle size, morphology and crystallinity of the related catalysts. After the evaluation on the catalytic performance for alkaline MOR, The TMNs-modified catalysts exhibited higher activity and lower onset potential potential compared with the commercial Pt/C. Among them, Pt-NbN/C showed the highest mass activity with 9.56-fold that of the commercial Pt/C. The faster charge transfer kinetics and reaction rate were confirmed by Tafel and EIS results. CA measurements indicated that they also exhibited higher stability and anti-CO poisoning ability for alkaline MOR, consistent with the CO stripping experiments. To quantitatively describe the realtionship of the electronic effect on the catalytic activity and CO tolerance, the d-band center was employed as a parameter to bulid the corresponding function. Interestingly, it was proposed that the rational d-band center could lead high MOR performance and anti-CO poisoning ability. The introduction of TMNs brought the evident shift of the Pt d-band center and boosted the catalytic activity and anti-CO poisoning ability for alkaline MOR.
研究领域:
电化学
·
催化材料科学
✓ 已验证
产品关联
DOI
高影响因子
ACS Applied Materials & Interfaces
·
2024
·
IF 8.3
Chaoqi Han,Wenwen Shi,Mengxue Huang,Qi Wang,Jie Yang,Jingchao Chen,Ruimin Ding,Xi Yin
Understanding the complex solvent effects on the microstructures of ink and catalyst layer (CL) is crucial for the development of high-performance anion exchange membrane fuel cells (AEMFCs). Herein, we study the solvent effects within the binary solvent ink system composed of water, isopropyl alcohol (IPA), commercial anion exchange ionomer, and Pt/C catalyst. The results show that the Pt/C particles and ionomer tend to form large aggregates wrapped with a thick ionomer layer in IPA-rich ink and promote the formation of large mesopores within the CL. With the increase of the water content in the ink, Pt/C particles are more likely to bridge to each other through wrapped FAA to form a well-connected three-dimensional network. The CL fabricated using water-rich ink shows smaller pores, higher porosity, and a more homogeneous ionomer network without the formation of large aggregates. Based on these results, we propose that the properties of the solvent mixture, including dielectric constant (ε) and solubility parameter (δ), affect the coulomb interaction of charged particles and surface tension at interfaces, which in turn affects the microstructure of ink and CL. By leveraging the solvent effects, we optimize the CL microstructures and improve the performance of AEMFC. These results may guide the rational design and fabrication of AEMFCs.
研究领域:
能源科学
·
材料科学
✓ 已验证
DOI
PubMed
高影响因子
CHEMICAL ENGINEERING SCIENCE
·
2022
·
IF 4.889
Xiaonan Duan,Jiabin Yin,Mengmeng Huang,Peixia Wang,Jisong Zhang
Halogenated aromatic anilines are series of crucial intermediates for the synthesis of pigments, medicines and pesticides in the fine chemistry. However, efficient inhibition of undesired dehalogenation is difficult to achieve in the commonly used batch reactors. Although employing continuous flow technology and modified catalysts could alleviate dehalogenation, obtaining high selectivity of halogenated aromatic anilines especially for brominated aromatic amines and iodine aromatic amines is still challenging. In this study, a continuous flow system based on micro-packed bed reactor was developed and a kinetic model of the hydrogenation of halogenated nitrobenzene was established. Kinetic parameters for the reductions of p -chloronitrobenzene, p -bromonitrobenzene and p -iodonitrobenzene were acquired and the kinetic model exhibited good fit for the transformation of each substance. Moreover, the accuracy of kinetic model was validated by the comparison with the values in literature. The obtained kinetic model offered helpful information for the process optimization of hydrogenation of halogenated nitroaromatics in continuous flow system.
研究领域:
化学工程
·
催化化学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF CATALYSIS
·
2018
·
IF 6.759
Qifan Wu,Bin Zhang,Chao Zhang,Xiangchun Meng,Xinluona Su,Shan Jiang,Ruhui Shi,Yan Li,Weiwei Lin,Masahiko Arai,Haiyang Cheng,Fengyu Zhao
The selectivity of 3-nitrostyrene (NS) hydrogenation over 0.5 wt-% Pt catalysts supported on carbon materials can be switched simply by changing reduction temperature. When the reduction temperature was 150 °C, 1-ethyl-3-nitrobenzene (ENB) was mainly produced in a selectivity of 93% at a conversion of 95% (at 100 °C). When the reduction was conducted at a higher temperature of 450 °C, in contrast, the main product was switched to 3-aminostyrene (AS) in a selectivity of 96% at a conversion of 91%. That is, the Pt/C catalysts reduced at low and high temperatures could preferentially catalyze the hydrogenation of vinyl and nitro groups of NS, respectively. This switching of the product selectivity may be ascribed to actions of surface oxygen-containing functional groups and surface hetero P species. The quantity and nature of these surface species were examined in detail by a few different methods. For the low-temperature reduced catalyst, surface acidic groups present close to Pt nanoparticles (∼2 nm) would interact with the nitro group of a NS molecule and make its vinyl group more likely to interact with the surface active metal species of Pt nanoparticles; this facilitates the hydrogenation of the latter and produces ENB selectively. For the high-temperature reduced catalyst, however, P species would interact with Pt and form Pt-PO x complex, on which a NS molecule is likely to be adsorbed with its nitro group, facilitating the selective production of AS via its hydrogenation. It is demonstrated that surface functional groups and surface hetero atoms (like P), in addition to main active metal species (like Pt), should have direct actions in the catalysis for such a catalyst that exposes a larger quantity of surface functional groups and/or hetero atoms compared to the number of supported metal nanoparticles .
研究领域:
催化
·
化学工程
·
物理化学
✓ 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）