CHEMICAL ENGINEERING JOURNAL
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2024
·
IF 13.3
Huihui Deng,Baozhen Li,Wenchun Zheng,Qin Sun,Mengjia Zhu,Jun Zuo,Yu Tang,Lizhi Wu,Li Tan
Propane dehydrogenation is one of the most promising routes for propylene production due to its single reactant, product and high economic efficiency. For Co-based catalysts, the state of Co species is one of the important factors affecting the performance of propane dehydrogenation. Here, we designed zeolite Silicalite-1 (S-1) with different silanol nests content as support to investigate the effect of silanol nests content to form Td-Co(II) species. It is found that the content of silanol nests in the S-1 supports have a linear correlation with the formation of T d -Co(II) species and corresponding PDH catalytic activity through the study of the catalyst structure-performance relationship. And the silanol nests of S-1 could be fully coordinated with 0.5 wt% Co content over 0.5Co/S-1-1-HTS in the form of T d -Co(II) species to maximize the Co atomic utilization. Correspondingly, 0.5Co/S-1-1-HTS shows the most excellent catalytic activity and stability, with C 3 H 6 generation rate of 3014 mmol C 3 H 6 g Co −1 h −1 and deactivation rate of 0.07 h −1 at 550 °C.
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
Molecular Catalysis
·
2025
·
IF 4.9
Rong Chen,Peng Wang,Lizhi Wu,Li Tan,Yu Tang
PtSn bimetallic catalysts applied in propane dehydrogenation (PDH) reaction suffer from deactivation at high temperatures (500–700 °C) due to metal segregation and Sn-rich cluster formation. This study demonstrates that supporting PtSn catalysts on Silicalite-1 zeolite (S-1) enhances Sn dispersion through interactions with silanol hydroxyl groups, enabling effective regeneration of Pt-rich PtSn clusters even after 15 reaction-regeneration cycles. Comprehensive characterizations reveal that silanol nests play a critical role in redispersing metal species during regeneration, minimizing aggregation, and maintaining catalytic activity. The enhanced metal-support interactions significantly improve catalyst regenerability and stability, addressing key challenges in industrial PDH processes. This work highlights the importance of Sn dispersion and metal-support interactions in designing durable and efficient PtSn catalysts, offering practical insights for sustainable propylene production.
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
CHEMICAL ENGINEERING SCIENCE
·
2018
·
IF 3.306
Xunan Hou,Linzhou Zhuang,Beibei Ma,Shuixia Chen,Hui He,Fengqin Yin
In this work, we report a new route to improve the CO 2 adsorption performance of solid amine adsorbents. Platelet mesoporous silicas with abundant surface silanols were prepared by emulsion synthesis followed by simple solvent extraction. These silanol-rich silica particles were then functionalized with branched polyethyleneimine (BPEI) by grafting or impregnation to prepare CO 2 adsorbents. Silanol-rich silicas grafted with BPEI exhibited 70% higher amine density and 47% higher CO 2 adsorption capacity than its calcined counterpart. The adsorbent achieved a maximum CO 2 adsorption efficiency up to 13.82 mmol CO 2 /g-BPEI. Adsorbed species found in the infrared spectra suggested that silanols may contribute to the enhanced CO 2 adsorption efficiency on grafted amines. Silanol-rich silica functionalized with BPEI retained more porosity than its calcined counterparts, which may account for its superior CO 2 adsorption capacity. Silanol-rich silica impregnated with amines achieved the highest CO 2 adsorption efficiency ever reported (5.65 mmol/g, 526.7 mg/g-BPEI). Adsorption kinetic modeling confirmed that silanol-rich adsorbent provides better CO 2 diffusion pathways. These potential benefits of silanol-amine interaction, coupled with platelet mesoporous structure and branched polyamine chains, opens a new pathway to high-performance adsorbents for CO 2 capture.
研究领域:
材料科学
·
环境科学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF CHROMATOGRAPHY A
·
2016
·
IF 3.926
Hai-yan Liu,Zhi-yong Li,Dan Liu,Ying-Wen Xue,Zhi-guo Shi
Octadecyl bonded silica (ODS) is the most popular packing for reversed-phase chromatography. However, it generally demonstrates bad resolution for polar analytes because of the residue silanols and its poor stability in aqueous mobile phase. To address the problem, a new reversed-phase packing containing both polar-embedded and polar-endcapped moieties was proposed. It was prepared by a very simple method, in which the epoxide addition reaction of 3-glycidoxypropyltrimethoxysilane with 1-octadecanethiol proceeded simultaneously with the reaction of silane coupling onto silica particles. By controlling the molecular ratio of 3-glycidoxypropyltrimethoxysilane to 1-octadecanethiol higher than 1.0 (1.56 for the present study), both polar-embedded and polar-endcapped moieties were achieved onto the packing. The performance of the packing was evaluated in detail. The results demonstrated that neutral, acidic and basic analytes were well separated on the packing. The column efficiency for phenanthrene was 34,200 theoretical plates per meter. In addition, four nucleotides can be separated in 100% phosphate buffered saline solution with good reproducibility, which indicates the packing has good stability in aqueous mobile phase. Amitriptyline, a typical basic analytes, was eluted out with relatively symmetric peak shape (asymmetry factor of 1.36), which implies that the packing has not suffered from the negative effect of residue silanols significantly. Good stability in buffer solution of pH ranging from 2.0 to 10.0 was also documented for the packing.
研究领域:
分析化学
·
色谱学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
APPLIED CATALYSIS A-GENERAL
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2022
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IF 5.723
Guoqiang Hou,Tingjun Fu,Xin Li,Qian Ma,Zhong Li
HZSM-5 catalysts with abundant silanol nests were fabricated by removing framework Al, which effectively promoted the selective alkylation of toluene with methanol by inhibiting the deep alkylation of aromatics to heavy aromatics and the conversion of methanol to light hydrocarbons. Correspondingly, the alkylation efficiency reached 65.3% at a toluene conversion of 31.3% over dealuminated HZSM-5, higher than the 55.2% efficiency and 28.0% conversion of parent zeolites, respectively. In situ DRIFTS and single-factor experimental clarified that toluene adsorption was enhanced and methanol to hydrocarbons was inhibited with the presence of silanol nests. Additionally, by increasing the crystal size of HZSM-5 with silanol nests from 2 to 5 µm, para-xylene selectivity was increased from 36.1% to 65.5% because of the enhanced diffusion barrier . The finding of the positive effect of the silanol nests on toluene alkylation can provide a solid fundamental basis for the rational design of catalysts.
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
Water
·
2024
·Vol. 16
·期 16
·2218
·
IF 3
Zhichao Chen,Yulin Min,Xin Zhao,Penghui Shi,Hongxiu Lu
Ceramsites are extensively employed as substrates for adsorbents in studies focused on phosphorus adsorption, leaving ceramsites crafted from diatomite less explored. Diatomite-based ceramsite, with its distinct porous architecture and surface silanol functionalities, is adept at supporting a variety of metal oxides, presenting a distinct advantage over other ceramsite variants. In light of this, the present study embarked on producing diatomite-based ceramsite using diatomite as the foundational material, subsequently enhancing it through the incorporation of Fe, thus yielding an Fe-modified diatomite-based ceramsite. Through adsorption testing, the modified ceramsite demonstrated a significantly improved adsorption capacity of 4.06 mg P/g, marking a substantial enhancement from the initial capacity of 0.9 mg P/g. The process of phosphorus adsorption exhibited a strong alignment with the Langmuir isotherm model and the pseudo-second-order kinetic model. In-depth analyses employing XRD, FTIR, zeta potential, and XPS techniques have revealed that the principal mechanisms driving the adsorption process are centered on interactions involving electrostatic forces, the formation of chemical precipitates, and the exchange of ligands. This investigation not only opens new avenues for the application of diatomite-based ceramsite but also lays down a theoretical foundation for its modification, thereby enriching the spectrum of its utility.
研究领域:
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
JOURNAL OF SEPARATION SCIENCE
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2019
·Vol. 43
·期 2
·398-405
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IF 2.516
Xiaojing Lai,Jing Liu,Xin Xu,Jie Li,Baojun Zhang,Lijun Wei,Hongping Cai,Xianglei Cheng
In reversed-phase liquid chromatography, tetracycline antibiotics yield broad and asymmetrical peaks, as a result of their ionic interaction with the anionic free silanol groups and metal ion present in the silica-based stationary phases (commonly derivatized with C18 groups). These frequently encountered difficulties were absolutely eliminated based on dual effect when methanesulfonic acid was employed as an eluent additive. The study revealed that the performance of methanesulfonic acid to minimize the “silanol effect” is mainly explained by both direct neutralization of the anionic silanol sites and electrostatic attraction with analytes. Based on these dual action mechanisms, an ultrasensitive method has been successfully developed for the simultaneous determination of tetracycline antibiotics and their derivatives (minocycline, oxytetracycline, tetracycline, chlortetracycline, metacycline, doxycycline, 4-epitetracycline, and 4-epichlortetracycline) in bovine milk with convenient ultraviolet detection within 15 min. Under the optimal conditions, the calibration curves showed good linearity ( r 2 > 0.999) for all analytes in the range of 1∼200 ng/mL with the instrument limits of detection as low as 0.3 ng/mL. The study sheds new light on suitable additives to analyze basic compounds with the advantage of good compatibility with MS detection.
研究领域:
分析化学
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药物分析
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食品安全
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Catalysts
·
2019
·Vol. 9
·期 10
·834
·
IF 3.444
Jun Zhou,Xiaoqing Cao,Hongna Wang,Song Li
The catalytic oxidation of silanes to produce silanols using water as an oxidant at mild temperatures is a major challenge in Si-H activation. Highly efficient and easy-to-recycle catalysts based on Pd nanoparticles are in high demand. In this study, Pd nanoparticles embedded in an MgO porous overlayer on an Mg plate as a structured catalyst was prepared by the plasma electrolyte oxidation (PEO) technique. The Pd/MgO catalyst is strongly anchored to the MgO plate, building a structured catalyst. Fabrication parameters such as the temperature of the electrolyte and applied voltage significantly influenced the structure of the obtained Pd/MgO catalyst and in turn its catalytic activity. The catalytic activities of Pd/MgO were evaluated by activation of a Si-H bond for catalyzing the aqueous oxidation of silanes to silanol at mild temperatures. The catalytic activity of Pd nanoparticles is favored by their electro-deficient state due to influence from the MgO substrate. The Pd/MgO catalyst exhibits good performance stability during recycling. This work paves the way for fabricating structured catalysts with long-term stability and enhanced metal–oxide interaction.Keywords:structured catalyst;Pd nanoparticles;metal–oxide interaction;silanol
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
INTERNATIONAL JOURNAL OF PHARMACEUTICS
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2024
·
IF 5.3
Junjie Wang,Xiang Guo,Xingchun Jiang,Xueyan Hu,Cui Wang,Yang Han,Hao Wu
This study investigates the effect of silanol density on the surface of glass containers on the stability of monoclonal antibody (mAb) formulations subjected to mechanical stress. By calcining Type I glass containers at different temperatures, we altered the concentration of silanols on the glass surface and examined its impact on the stability of protein formulations under mechanical stress. Contact angle measurements and Fourier Transform Infrared (FTIR) spectroscopy indicated that silanol formation influences the hydrophilicity of the surface. Additionally, mAb solutions filled in Type I glass containers with varying silanol densities were repeatedly dropped from a height of 0.5 m to simulate mechanical stress during transport. The results demonstrated that increasing surface silanol density reduces protein monomer loss and the formation of protein aggregates and subvisible particles. Furthermore, protein aggregates and subvisible particles formed by dropping did not activate the complement in human serum in vitro. Adjusting the silanol density on the glass container surface offers an economical and environmentally friendly approach to improving the stability of mAb formulations during transport and use.
研究领域:
生物技术
·
制药工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Small
·
2024
·
IF 13
Junshuo Cui,Shiyi Liu,Wenkang Li,Xiyu Wang,Li Zhen,Ying Xiong
High efficient dispersant that meanwhile possesses additional functions is highly desirable for the fabrication of graphene-based composite. In this paper, a new reactive dispersant, multi-silanols grafted naphthalenediamine (MSiND), is synthesized, which shows superiority compared with conventional dispersants. It can not only stabilize graphene in water at a high concentration of up to 16 mg mL −1 , but also simultaneously be applicable for ethanol medium, in which the graphene concentration can be as high as 12 mg mL −1 at the weight ratio of 1:1 (MSiND:graphene). The dispersion is compatible with multi-matrixes and affinity to various substrates. In addition, MSiND exhibits excellent reactivity due to the existence of high-density silanol groups. Tough graphene coatings are constructed on glass slides and non-woven fabric simply by direct painting and dip-coating. Moreover, with the assistance of MSiND, graphene-doped phase-change coatings on hydrophobic non-woven fabric (e.g., functional mask) are prepared via the spray method. The composite coatings show enhanced mechanical strength and excellent energy storage performance, exhibiting great potential in heat preservation and thermotherapy.
研究领域:
材料科学
·
化学工程
✓ 已验证
DOI
高影响因子
JOURNAL OF ADHESION SCIENCE AND TECHNOLOGY
·
2015
·
IF 0.961
Shufang Jiang,Shangwen Zha,Lanjun Xia,Rong Guan
A series of diphenylsilanediol modified epoxy resins and novel curing agents were synthesized. The modified epoxy resins were cured with regular curing agent diethylenetriamine (DETA); the curing agents were applied to cure unmodified diglycidyl ether of bisphenol A epoxy resin (DGEBA). The heat resistance, mechanical property, and toughness of all the curing products were investigated. The results showed that the application of modified resin and newly synthesized curing agents leads to curing products with lower thermal decomposition rate and only slightly decreased glass transition temperature (Tg), as well as improved tensile modulus and tensile strength. In particular, products cured with newly synthesized curing agents showed higher corresponding temperature to the maximum thermal decomposition rate, comparing with products of DGEBA cured by DETA. Scanning electron microscopy micro images proved that a ductile fracture happened on the cross sections of curing products obtained from modified epoxy resins and newly synthesized curing agents, indicating an effective toughening effect of silicon–oxygen bond.
研究领域:
材料科学
·
化学工程
✓ 已验证
DOI
高影响因子
Materials
·
2022
·Vol. 16
·期 1
·9
·
IF 3.748
Weiqing An,Xiangan Yue,Jirui Zou,Lijuan Zhang,Yu-Chun Fu,Rongjie Yan
Anomalous solid-like liquids at the solid–liquid interface have been recently reported. The mechanistic factors contributing to these anomalous liquids and whether they can stably exist at high vacuum are interesting, yet unexplored, questions. In this paper, thin slices of silica tubes soaked in hexadecane were observed under a transmission electron microscope at room temperature. The H-spectrum of hexadecane in the microtubules was measured by nuclear magnetic resonance. On the interior surface of these silica tubes, 0.2–30 μm in inside diameter (ID), a layer (12–400 nm) of a type of non-volatile hexadecane was found with thickness inversely correlated with the tube ID. A sample of this anomalous hexadecane in microtubules 0.4 μm in ID was found to be formable by an ion beam. Compared with the nuclear magnetic resonance H-spectroscopy of conventional hexadecane, the characteristic peaks of this abnormal hexadecane were shifted to the high field with a broader characteristic peak, nuclear magnetic resonance hydrogen spectroscopy spectral features typical of that of solids. The surface density of these abnormal hexadecanes was found to be positively correlated with the silanol groups found on the interior silica microtubular surface. This positive correlation indicates that the high-density aggregation of silanol is an essential factor for forming the abnormal hexadecane reported in this paper.Keywords:solid-liquid interface;transmission electron microscope;silica;microtubules;hexadecane;surface-silanol
研究领域:
材料科学
·
化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）