JOURNAL OF COLLOID AND INTERFACE SCIENCE
·
2022
·
IF 9.965
Minghu Zhao,Jiuhu Zhao,Ran Ding,Rongshu Zhu,Haiyan Li,Zhi Li,Jingwen Zhang,Yongji Zhu,Huiying Li
The existence of sulfur dioxide and water vapor in the flue gas generated from waste-to-energy stations could lead to catalyst deactivation , which has adverse effects on NO x removal. It is thus particularly important to study the reaction mechanism of catalyst resistance to poisoning. Herein, we report the mechanism of In-Co 3 O 4 -Ga 2 O 3 /H-Beta catalyst to SO 2 and H 2 O resistance in the selective catalytic reduction (SCR) of NO x by CH 4 . The catalyst could achieve 74.6% NO x removal efficiency in the presence of 100 ppm SO 2 and 5% H 2 O. In this catalyst, Co 3 O 4 is attributed to enhancing the reversible poisoning of SO 2 and CH 4 activation and increasing the number of Brønsted acid sites by decomposing H 2 O. However, the InO + active center was still eroded by a small amount of water vapor, leading to a reduction in NO x removal efficiency. The addition of Ga 2 O 3 primarily provided an important intermediate NO 2 for CH 4 -SCR reaction and reduced the aggregates of Co 3 O 4 to increase the exposure of indium sites, and could reduce a part of SO 2 to S 2− . This study provides a good candidate for preparing catalysts with superior resistance towards SO 2 and H 2 O for CH 4 -SCR.
研究领域:
环境科学
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催化化学
✓ 已验证
DOI
高影响因子
Catalysis Science & Technology
·
2025
·
IF 4.2
Mingkang Zhang,Jingwei Wu,Haolin Yang,Xiaohan Wang,Zebao Rui,Junfei Chen
Selective catalytic reduction of nitrogen oxides with methane (CH4-SCR) is an effective way to simultaneously eliminate NOx and CH4 emissions. Development of efficient CH4-SCR reaction system with high NOx reduction activity and selectivity is highly desirable for its commercial application. Herein, a two-part relay reaction system, including sequentially Co@S-1 and In-Ce/H-Beta catalysts, is designed for boosting CH4-SCR. In this system, the Co@S-1 with high redox ability boosts NO oxidation to NO2 and generates key intermediate CH3NO2 that can partially be in situ oxidized and the excessive can migrate to In-Ce/H-Beta. Meanwhile, the inner synergistic effect between InO+ and CeO2 species on In-Ce/H-Beta not only exhibits fair CH4-SCR performance, also facilitates the formation of NO- 3 species to react with the migrated CH3NO2 from Co@S-1. Benefiting from the combination between outer active sites synergy and inner active sites synergy, the simultaneous efficient conversion of NOx (T50 = 380 ℃) and CH4 (T50 = 425 ℃) with well durability is achieved.
研究领域:
环境科学
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催化化学
✓ 已验证
产品关联
DOI
高影响因子
Catalysis Science & Technology
·
2017
·Vol. 7
·期 24
·6050-6058
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IF 5.773
Wei Zhang,Wei Hou,Tongsuo Meng,Wenxia Zhuang,Jingyan Xie,Yu Zhou,Jun Wang
Vanadium (V)-containing all-silica beta-zeolites (VSi-Beta) were directly synthesized using a dry-gel-conversion route, in which the gel was prepared from the acid-catalysed co-hydrolysis of a silica precursor and ammonium metavanadate. Besides the framework isolated V species, VSi-Beta contained tetrahedral [V2O7]4− and (VO3)nn− species that were bonded to the framework with a high dispersion. These V species resisted the over-oxidation of fructose and efficiently catalyzed the oxidation of 5-hydroxymethylfurfural (HMF) into 2,5-diformylfuran (DFF). As a result, VSi-Beta demonstrated high activity in the one-pot and one-step conversion of fructose into DFF using atmospheric oxygen (O2) in the presence of sulfuric acid, affording a high yield of 86.3% and a maximum turnover number (TON) of 270. The catalyst can be easily recovered by filtration and exhibits good reusability. Various other carbohydrates (glucose, sucrose, inulin, raffinose, maltose and starch) were also effectively converted into DFF using VSi-Beta.
研究领域:
化学工程
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催化科学
✓ 已验证
产品关联
DOI
高影响因子
Catalysis Science & Technology
·
2024
·
IF 4.4
Ling Ding,Lou Gao,Di Pan,Ke Du,Jiayu Yu,Wanyi Li,Yahong Zhang,Yi Tang
The utilization of racemic lactic acid (rac-LA) produced via chemocatalytic conversion for polylactic acid (PLA) synthesis remains limited due to the formation of undesired mesomeric lactide (meso-LD), a by-product that arises during the conversion process. This study proposes the use of shape-selective H-Beta zeolite to reduce the formation of meso-LD in lactide (LD) by leveraging its selectivity towards different lactic dimers (L2A) in a one-step catalytic conversion of rac-LA to LD. Experimental results from various LA solutions with different L2A content indicate that the L2A content is critical for maximizing the selectivity of racemic lactide (D/L-LD), thus confirming the shape-selective nature of H-Beta zeolite towards L2A. Additionally, it is found that increasing the reaction temperature and employing structurally reconstructed H-Beta zeolite with more regularized channels as a catalyst can further decrease meso-LD formation, and a LD yield of 60% with a D/L-LD/meso-LD ratio of 2.26 can be achieved under optimal catalyst and reaction conditions. Despite the coexistence of D/L-LD and meso-LD in the final product, this study marks a significant step towards controlling the stereoisomer distribution of LD synthesized from rac-LA derived from chemical conversion.
研究领域:
化学工程
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材料科学
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催化
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF CATALYSIS
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2023
·
IF 7.3
Zhiwei He,Qifeng Lei,Weili Dai,Hongbo Zhang
Alkene epoxidation is a very important reaction process for the selective generation of chiral products, usually performed in some solvent(s) with different polarity, solubility and proton properties. These physical properties are entangled and do not explain very well whether they are mainly against population or stability of the reaction intermediates during catalysis. Here, we investigate how different solvents with known polarity properties (CH 3 CN, (CH 3 ) 2 CO, CH 3 OH, etc.) affect the C 6 H 10 transformation over Ti-Beta catalysts. Combining kinetic measurements, thermodynamic investigations and isotope experiments, the solvent was found not to change the reaction path or mechanism, with C 6 H 10 epoxidation most likely following the Eley-Rideal mechanism and C 6 H 10 O hydration following a Langmuir-Hinshelwood mechanism, and both nucleophile and carbonium were found to be involved in the transition state (c.a. SN 2 process) of hydration. However, in the epoxidation reaction of C 6 H 10 with CH 3 CN and (CH 3 ) 2 CO as solvents, the reaction order of [C 6 H 10 ] is subtly different and the epoxidation rate increases with increasing volumetric fraction of CH 3 CN in the binary mixture, which indicates that the solvent affects the concentration of dissolved C 6 H 10 surrounding the active sites and leads to the corresponding differences in activity and product selectivity. Nevertheless, the measured apparent reaction barrier (energy difference between transition state and MASIs) spans the elementary step of solvent modification, thus allowing for the observation of negligible solvent thermodynamic modification. Collectively, these findings provide clear evidence of solvent effects on alkene epoxidation and can be easily extended to some other reactions in solvents.
研究领域:
催化化学
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物理化学
✓ 已验证
产品关联
DOI
高影响因子
Sustainable Energy & Fuels
·
2020
·Vol. 4
·期 10
·5327-5338
·
IF 5.503
Meng Xia,Wenjie Dong,Zheng Shen,Shaoze Xiao,Wenbo Chen,Minyan Gu,Yalei Zhang
In the catalytic transformation of biomass into valuable chemicals, it is extremely important to inhibit undesirable reactions to increase the yield of target products. In this study, the introduction of indium and tin into Beta zeolites promoted the transformation of glucose into lactic acid with a high yield of 53%. Selective experiments and a developed kinetic model confirmed the sensitivity of the main reaction rate to the action of tin, including those of the isomerization and retro-aldol condensation reactions, and shielding of the side reactions by indium. An in-depth analysis of the catalyst acidity showed that weak Lewis acidity in the indium and tin species promoted the main reaction steps, whereas the decreased amount of strong Lewis acidity by introduction of indium into the Sn-Beta catalyst suppressed the side reactions. The coupling of multifunctional active sites provides a new strategy for addressing challenges in commercial lactic acid production.
研究领域:
化学工程
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催化科学
✓ 已验证
DOI
高影响因子
ANALYTICA CHIMICA ACTA
·
2024
·
IF 5.7
Li Yang,Ru Liu,Chaodan Li,Boning Gu,Jiannong Ye,Li Chen,Qingcui Chu
Background With the rapid growth of the demand for optically pure compounds in the fields of biology, medicine and stereospecific synthesis, it is of great importance to develop efficient, economical, simple enantioseparation and analysis methods. Open tubular capillary electrochromatography (OT-CEC) has attracted much attention in the field of chiral separation , but its column capacity and the sensitivity of common-used optical detection are relatively low. Zeolite beta nanomaterial is both enantioselective and size-selective, providing suitable chiral microenvironment for chiral recognition, and amperometric detection (AD) avoids the low sensitivity caused by the short optical path in optical detection to some extent. Results Zeolite beta nanomaterials with different particle sizes (25, 50 and 200 nm) were synthesized, and the morphology and structure were characterized by scanning electron microscopy and X-ray diffraction. Then, a novel chiral OT column was prepared by one-step method using zeolite beta nanomaterial as chiral stationary phase, and its separation performance was characterized by miniaturized CEC with AD (mini-CEC-AD) device. Under the optimum conditions, six groups of chiral drugs achieved baseline separation. Norepinephrine enantiomers were used for evaluating the inter-day, intra-day and inter-column reproducibility of the prepared open-tubular column. The relative standard deviations of migration time, peak area, resolution and selectivity factor were within 8.7 %. The limits of detection for norepinephrine enantiomers were 0.18 μg mL −1 (S/N = 3), and the average recoveries were in range of 96.7–105.0 %. This developed method has been successfully applied to the analysis of impurity enantiomer in potassium dichromate (+)-norepinephrine injection sample. Significance Zeolite beta nanomaterial was used as the stationary phase to prepare chiral OT columns for the first time, and this one-step preparation method is simple and easy. The introduction of zeolite beta enriches the types of chiral stationary phase materials in electrochromatographic columns, and mini-OT-CEC-AD system provides an alternative for fast enantioseparation of chiral compounds.
研究领域:
分析化学
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药物化学
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生物医学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ACS Applied Materials & Interfaces
·
2025
·
IF 8.2
Chen Liu,Jin Hu,Haichang Zhang,Jiaxin Wu,Chunsheng Shi,Biao Chen,Chunnian He,Naiqin Zhao
Poly(ethylene oxide) (PEO)-based solid polymer electrolytes (SPEs) demonstrate strong electrode adhesion and facile processability, making them promising candidates in all-solid-state lithium metal batteries (ASSLMBs). However, poor ionic conductivity, low Li+ transference number, and insufficient mechanical strength greatly limit their practical application. Zeolite, a porous ceramic material rich in active sites, shows significant potential as a filler in the PEO-based SPEs. In this study, we prepared heteroatomic Sn-Beta zeolite with high Lewis acid activity through a simple two-step postsynthesis process and explored the mechanism of action of metal acidic sites on Li+ dissociation and transport. The Lewis acidic metal sites in the Sn-Beta zeolite effectively weaken the coordination environment of Li+ by binding the O atoms in PEO via metal–oxygen bonds, facilitating the transfer of Li+ along the PEO polymer chains. Moreover, it can promote the dissociation of the lithium salt by anchoring TFSI– anions, resulting in the release of free Li+. The obtained SPE (PL-Sn-Beta) exhibits a high ionic conductivity of 1.40 × 10–3 S cm–1 at 60 °C and a Li+ transference number of up to 0.51. Furthermore, the ordered pore channels of the Sn-Beta zeolite provide uniform Li-ion transport pathways, facilitating homogeneous Li+ deposition. As a result, the lithium symmetric cell with PL-Sn-Beta demonstrates a stable lithium plating/stripping cycle performance for over 2200 h at 60 °C and 0.1 mA cm–2. Meanwhile, the initial discharge capacity of the Li/PL-Sn-Beta/LiFePO4 full cell reaches 145.6 mAh g–1 at 1 C and 60 °C, and the capacity retention rate is 81.5% after 500 cycles. This work provides theoretical insights into the mechanism of zeolite fillers in SPEs as well as new design concepts.
研究领域:
材料科学
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电化学
·
能源存储
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Catalysis Science & Technology
·
2023
·Vol. 13
·期 13
·3974-3986
·
IF 5
Meng Xia,Zheng Shen,Shaoze Xiao,Minyan Gu,Yalei Zhang
During the catalytic transformation of biomass into valuable chemicals, enhancing the yield of target products and inhibiting undesirable reactions are vital but challenging. In this study, a facile and efficient method for synthesizing a hierarchical bimetallic Mg–Sn-Beta-H zeolite was developed. Using this method, the simultaneous fabrication of catalytically active sites and hierarchical structures was achieved. Selective experiments and kinetic analysis confirmed that the catalytically active sites and hierarchical structures in the catalyst exhibited a clear synergistic effect on the transformation of glucose into lactic acid with a high yield of 62.7%, and the lactic acid yield remained above 58% after reusing the catalyst four times. An in-depth analysis of the synergistic catalysis mechanism demonstrated that strong and weak Lewis acidity in the catalytically active sites promoted the main reaction steps, including isomerisation and retro-aldol condensation, whereas the hierarchical structure induced by the introduction of magnesium into the parent Sn-Beta zeolite regulated the main reaction steps and suppressed the side reactions. The coupling of multifunctional active sites and hierarchical structures provides a new strategy for addressing the challenges of commercial lactic acid production.
研究领域:
催化化学
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材料科学
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生物工程
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF HAZARDOUS MATERIALS
·
2020
·
IF 9.038
Zhiguo Zhu,Haikuo Ma,Hao Xu,Bo Wang,Peng Wu,Hongying Lü
As to metallosilicate zeolites, ions with larger size such as Ta 5+ in the gels greatly retarded their crystallization during the hydrothermal synthesis, affording long-winded synthesis periods, up-limited framework-substituted metal contents, or even frustrated outcome. An efficient hydrothermal synthesis strategy for metallosilicate, in this case of Ta framework-substituted *BEA zeolite, via structural reconstruction was proposed to stride the gap. The Ta content in our developed Ta-Beta-Re-50 zeolite achieved up to 5.48 % (Si/Ta = 52), breaking through the limitation of Ta contents for conventional method (Si/Ta > 100). Additionally, this Ta-Beta-Re zeolite possessed nanosized crystals (20–40 nm) and short crystallization time (8 h), significantly improving space-time yields of practical zeolite production. Through spectroscopic study, it was confirmed that the existence of zeolite structural units intensively facilitated the formation of nucleation and crystal growth. This innovative Ta-Beta zeolite demonstrated high catalytic performances for oxidation desulfurization, far outperforming traditional fluoride-mediated Ta-Beta-F, which was ascribed to its excellent diffusion properties and incredible high isolated Ta contents. Additionally, the catalytic performance of Ta-Beta-Re could be regenerated after simple calcination and the deactivation may be caused by pore blocking of organics. This work provides a new method for rationally design and construction of metallosilicate materials with high activity for catalytic oxidation applications, which can bridge the conceptual and technical gap between periodic trends and zeolite material synthesis.
研究领域:
化学工程
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材料科学
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催化
·
环境科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Chemical Engineering Journal Advances
·
2020
·
IF 0
Jiuhu Zhao,Zhengzhong Wen,Rongshu Zhu,Zhi Li,Ran Ding,Yongji Zhu,Tingkun Gu,Rong Yang,Zhenye Zhu
In this paper, In-metal oxide/H-Beta catalysts were synthesized by ion exchange method and In-Co 3 O 4 /H-Beta exhibited the highest catalytic activity for the selective catalytic reduction of NO x with CH 4 in presence of H 2 O and SO 2 . Thus, the synthesis conditions of In-Co 3 O 4 /H-Beta were optimized. The results showed that In-Co 3 O 4 /H-Beta exhibited excellent catalytic performance and high CH 4 selectively when the synthesis was carried out by ion exchange method, the ratio of Si and Al in H-Beta was 25, the ratio of Co 3 O 4 and H-Beta was 5:40, the concentration of ion exchange liquid was 0.033 M and calcination temperature was 500 °C. The NO x removal efficiency was about 87.6 % and N 2 selectivity could reach 96.3% in the presence of H 2 O and SO 2 . Through a series of characterizations, it was concluded that In-Co 3 O 4 /H-Beta owned stable catalyst structure, abundant Brønsted acid sites and the highest ratio of InO + /In 2 O 3 under the optimal synthesis conditions. In addition, the doped of Co 3 O 4 could inhibit the adsorption of sulfate species on the surface of In/H-Beta catalyst, leading to the excellent H 2 O and SO 2 resistance property.
研究领域:
环境科学
·
催化化学
✓ 已验证
DOI
MICROPOROUS AND MESOPOROUS MATERIALS
·
2018
·
IF 3.649
Li Gao,Zhiyuan Shi,Ubong Jerome Etim,Pingping Wu,Dezhi Han,Wei Xing,Svetlana Mintova,Peng Bai,Zifeng Yan
Beta-MCM-41(BM) composites consisting of Beta zeolite grown on MCM-41 type mesoporous structure were prepared. The composite materials were used as a support for stabilization of Pt. The Pt containing catalysts (Pt/HBM) were applied in n-heptane hydroisomerization reaction. The Pt/HBM catalysts showed higher n-heptane conversion and higher selectivity to isoheptanes in comparison to pure Beta and MCM-41. The results were explained by the accelerated diffusion of isoheptanes in the Pt/HBM composites, and the high concentration of acid sites with a moderate strength in the composites, which reduced the cracking of reactants and products. Based on the experimental results, an indexed isomerization factor (IIF) was deduced, which is correlated with the physical properties of the supports. The results indicated that the isoheptane yield of the catalysts is strongly dependent on the support (IIF). The general IIF descriptor for predicting the isomerization performance of support materials can provide precise guidance for the design of new micro-mesoporous composites.
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
危险品化学品经营许可证（带存储）