Science China-Chemistry
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2012
·Vol. 55
·期 6
·1167-1174
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IF 1.02
Lang WanZhong,Su Bo,Guo YaJun,Chu LianFeng
Four amine functionalized mesoporous catalysts were synthesized by grafting primary, dualistic and two secondary amines onto the channel walls of mesoporous silica, MCM-41. We examined the effects of organoamine loading amount on the acid-base synergism of the catalysts in the self-condensation reaction of n -butanal, a Knoevenagel condensation and a Henry reaction. We observed the balance of the amine and residual silanol amounts is crucial to the catalytic performances of the functionalized mesoporous catalysts. An optimum organoamine loading amount exists, which is dependent on the organoamine type. There is little difference in the optimum organoamine loading amount between different reactions. The secondary organoamine functionalized MCM-41 exhibits the best catalytic performance in the experimental range.
研究领域:
化学工程
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催化科学
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DOI
高影响因子
Reaction Kinetics Mechanisms and Catalysis
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2021
·Vol. 134
·期 2
·823-835
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IF 2.081
Wang Ying,He Runfa,Wang Cong,Li Gang
A kind of heterogeneous catalyst MCM-41-S-ImBr was prepared by grafting 1-vinyl-3-ethylimidazolium bromide ([VEIM]Br) on the surface of MCM-41. The catalyst was characterized by X-ray diffraction patterns, Fourier transform infrared spectroscopy and element analysis as well as scanning electron microscopy. It showed that [VEIM]Br was successfully grafted on MCM-41 and the catalyst possessed an average particle size of 1.4 µm with intact mesoporous structure. Moreover, the catalyst exhibited high catalytic activity in the cycloaddition reaction of CO 2 with epichlorohydrin without co-catalyst. The conversion of epichlorohydrin was 98.5% and the selectivity of cyclic carbonate was 98.3% at 130 °C under 1.6 MPa for 6 h. Reaction kinetic study indicated that the pseudo-first order rate constant was 0.223 ± 0.001 h −1 . It is proved that MCM-41-S-ImBr could be used at least 4 times without obvious decrease in catalytic performance. A possible reaction mechanism was also proposed: the quaternary imidazolium ion cooperatively worked with the bromide ion to catalyze the reaction. Graphical Abstract
研究领域:
材料科学
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催化化学
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高影响因子
INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
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2021
·
IF 3.764
Qiang Sun,Tianhao Li,Yu Mao,Hongxia Gao,Teerawat Sema,Shengyu Wang,Libin Liu,Zhiwu Liang
Amine-based CO2 capture is a promising method to limit global CO2 emissions. However, large thermal energy consumption for CO2 desorption during amine regeneration has limited large-scale worldwide applications. Here, we show that an efficient MCM-41-SO3H-0.6 catalyst presented a superior catalytic performance, decreasing the relative heat duty by one-third and enhancing the instantaneous desorption rate by up to 195% in comparison with the monoethanolamine (MEA) regeneration without catalysts. The excellent catalytic activity is related to the combination of the properties of mesopore surface area × total acid sites, and a possible catalytic mechanism is proposed for the MCM-41-SO3H catalysts. Furthermore, the experimental results in the MEA solution regeneration process were consistent with density functional theory calculations in revealing the catalytic desorption mechanism. This work demonstrated that MCM-41 functionalized with sulfonic acid group catalysts could play an essential role in the post-combustion CO2 capture technology using aqueous MEA for industrial applications.
研究领域:
化学工程
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环境科学
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DOI
高影响因子
EUROPEAN JOURNAL OF LIPID SCIENCE AND TECHNOLOGY
·
2022
·Vol. 124
·期 9
·2100254
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IF 3.196
Kainan Xing,Minghe Cao,Qinkai Zhu,Haojie Yin,Meizhen Lu,Jianbing Ji
Vegetable oils and their derivatives are of great interest because of their abundance and renewability. This paper prepares nonanal (N) and methyl 9-oxonanoate (M) from methyl epoxystearate (ME) with WO 3 ∙0.33H 2 O, WO 3 ∙H 2 O, and WO 3 ∙2H 2 O as catalysts and H 2 O 2 as the oxidant without the use of organic solvent. The reaction temperature, catalyst amount, H 2 O 2 amount, and reaction time effects on ME conversion and N/M yield are investigated. The results show that WO 3 ∙H 2 O has the best catalytic performance. The optimal reaction conditions are: reaction temperature 60 °C, reaction time 40 min, ME/H 2 O 2 /WO 3 ∙H 2 O molar ratio 1/1.2/0.4, under which the ME conversion and N/M yield reach 95% and 70%, respectively. WO 3 ∙ n H 2 O reacts with H 2 O 2 to form soluble tungsten anions, resulting in severe tungsten loss. Al-MCM-41 materials with different silicon to aluminum molar ratios are added to the reaction system as adsorbents to recover the catalyst by effective adsorption of tungsten anions. The adsorption performance improves as the Si/Al ratio decreases, however, the ME conversion and N/M yield decrease. Thus, 50 is the most suitable Si/Al ratio. The ME conversion and N/M yield can still reach 90% and 60% after four times of use. Practical applications : The nonanal has a natural fragrance and can be used in the cosmetic industry as well as in the preparation of bio-based surfactants. The methyl 9-oxonanoate can be converted into polymer monomers by hydrogenation or amination. The results show that WO 3 ∙ n H 2 O has good catalytic activity, and a satisfying yield of aldehyde products is obtained under mild reaction conditions.
研究领域:
化学工程
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可再生资源化学
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DOI
高影响因子
CHINESE JOURNAL OF CHEMISTRY
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2021
·Vol. 40
·期 8
·918-924
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IF 6
Jisheng Xu,Chengxiang Shi,Shuguang Zhang,Qiancheng Zheng,Lun Pan,Xiangwen Zhang,Ji-Jun Zou
Comprehensive Summary Non-oxidative ethane dehydrogenation is a promising route to produce ethene. Herein, PtSn supported catalysts were investigated to achieve better ethane dehydrogenation performance by introduction of different Zr promoters, i.e. , framework Zr and ZrO 2 , to mesoporous MCM-41. In-situ XRD, TEM and CO chemisorption show that aggregation of metal particles and phase segregation of Pt 3 Sn to Pt and PtSn 3 at high temperature occur for PtSn/M, leading to bad ethane dehydrogenation activity. Strong interaction between ZrO 2 and PtSn species, as proved by XPS, results in restrained metal particles, which promotes the initial reactivity. However, Pt phase generated on surface is disadvantageous for the desorption of produced ethene as indicated by CO-IR and C 3 H 6 -TPD, and pyridine-IR and NH 3 -TPD indicate strong acidity generated. Both deactivate the catalyst rapidly by deep dehydrogenation and coking. Moderate interaction between PtSn species and Si-O-Zr with much weaker acidity is formed when framework Zr is incorporated into MCM-41, which benefits the dispersion of metal particles, formation of Pt 3 Sn/Pt species and stabilization of metal species from phase segregation. Outstanding initial ethane conversion and ethene selectivity of ca. 99% were achieved for the optimal PtSn/ZrM, which is more coking-tolerant and stable by generating graphitic carbon mainly on support instead of active metals.
研究领域:
催化化学
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材料科学
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高影响因子
ACS Applied Materials & Interfaces
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2024
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IF 8.3
Mingzhao Liang,Zhaohong He,Lisheng Deng,Jun Li,Xianglong Luo,Hongyu Huang
MCM-41, a mesoporous material with a high surface area and tunable pore size, shows great potential for water vapor adsorption. However, due to its large pore size, the effective adsorption capacity at medium to low relative partial pressures is limited in adsorption chiller applications. In this work, MCM-41 was successfully synthesized at room temperature using cetyltrimethylammonium bromide (CTAB) as a templating agent. Pore size modulation was achieved by treating the MCM-41 gel with ethanol. The results indicated that ethanol likely exerted an inward force on the pore channels, reducing the pore size from 3.418 to 2.583 nm. The water vapor adsorption properties and hydrothermal stability of the ethanol-treated samples were significantly enhanced. Additionally, a dual-atmosphere calcination process at 450 °C was established, showing results comparable to the conventional 550 °C process in terms of template removal. The sample, which combined dual-atmosphere calcination with ethanol treatment, demonstrated a significant increase in the water vapor adsorption capacity, achieving a 1.3-fold improvement compared to the untreated sample. These results provide a feasible reference for the application of MCM-41 in adsorption chillers.
研究领域:
材料科学
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化学工程
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PubMed
高影响因子
Journal of Inorganic and Organometallic Polymers and Materials
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2021
·Vol. 32
·期 1
·161-168
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IF 3.543
Qin Yuanyuan,Wang Xiu,Shi Minxin,Huang Yuhua,Liu Xiaogang,Li Xiancai
In this paper, APTES was used as the functional monomer, reamed MCM-41 was used as the carrier, and epichlorohydrin was used as the crosslinking agent to prepare the Lanthanide ion-imprinted polymer, La-IIP. The effects of pH, time, temperature, and initial concentration on La-IIP adsorption were investigated, and the adsorption mechanism was discussed by fitting the adsorption data to various kinetic and thermodynamic models. The results showed that La-IIP reached adsorption equilibrium in 20 min at 338 K and pH = 5, and the maximum adsorption capacity was 272.2 mg/g. The La-IIP adsorption process conformed to the Langmuir adsorption model, and La-IIP showed strong selectivity for La(III) in the presence of interfering ions with similarproperties. 2 M hydrochloric acid solution was used to eluate La-IIP and re-adsorb lanthanum ion solution. After elution of La-IIP for five times, the adsorption remained at the initial value of 81%. It shows that La-IIP has stability and reusability.
研究领域:
材料科学
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环境科学
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高影响因子
CHINESE JOURNAL OF CATALYSIS
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2015
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IF 1.964
Fu Yang,Shuying Gao,Cuirong Xiong,Haiqing Wang,Jin Chen,Yan Kong
The different amounts of [5,10,15,20-tetrakis-(pentafluorophenyl)porphyrin] manganese chloride (TF 20 PPMnCl) were immobilized on amino-functionalized MCM-41 for catalysis of the hydroxylation of naphthalene . The samples were characterized by X-ray powder diffraction, N 2 adsorption/desorption isotherms, Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy, scanning electron microscopy, diffuse reflectance ultraviolet-visible spectroscopy, thermogravimetric and differential scanning calorimetry , and inductively coupled plasma mass spectrometry . The results indicated that the manganese porphyrins were axially coordinated on amino-functionalized MCM-41. The prepared samples showed remarkable catalytic activity in the hydroxylation of naphthalene with meta -chloroperbenzoic acid as the oxidant. The catalyst could be reused several times without loss of its activity.
研究领域:
化学
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材料科学
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催化反应
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DOI
高影响因子
RSC Advances
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2019
·Vol. 9
·期 40
·23061-23070
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IF 3.049
Libo Peng,Qinglong Xie,Yong Nie,Xuejun Liu,Meizhen Lu,Jianbing Ji
The oxidative cleavage of vegetable oils and their derivatives to produce bio-based aldehydes is a potentially useful process, although the aldehyde products are readily oxidized to carboxylic acids and thus seldom obtained in high yields. The present study developed a room-temperature method for the synthesis of bio-aldehydes via the oxidative cleavage of vegetable oil-derived epoxides, using H2WO4 as the catalyst, H2O2 as the oxidant, and t-BuOH as the solvent. Reactions were carried out at temperatures ranging from 25 to 35 °C for 3.5–10.5 h, and provided >99% conversion and >90% aldehyde yield. In particular, an approximately 97% yield was obtained at 25 °C after 10.5 h. As the reaction proceeded, the H2WO4 dissolved to form a W-containing anion. Several mesoporous Al-MCM-41 materials having different Si/Al ratios were hydrothermally synthesized and used as adsorbents to recover the catalyst by adsorbing these anions. The adsorption capacity of the Al-MCM-41 was found to increase with decreases in the Si/Al ratio. The Al-MCM-41 had little effect on the oxidative cleavage reaction at 25 °C, and thus could be directly added to the reaction system. The excellent anion adsorption performance of the Al-MCM-41 greatly improved the reusability of the H2WO4 catalyst. When using the Al-MCM-41 with the best adsorption performance, there was no significant decrease in the activity of the catalyst following five reuses.
研究领域:
化学工程
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生物化学
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材料科学
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DOI
PubMed
高影响因子
JOURNAL OF MEMBRANE SCIENCE
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2014
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IF 4.908
Hong Wu,Xueqin Li,Yifan Li,Shaofei Wang,Ruili Guo,Zhongyi Jiang,Chan Wu,Qingping Xin,Xia Lu
Facilitated transport mixed matrix membranes (FT-MMMs) were fabricated by incorporating polyethylenimine functionalized ordered mesoporous silica (PEI-MCM-41) into poly(ether-block-amide) (Pebax ® MH 1657). The polyethylenimine both in the pore channels and on the surface of MCM-41 rendered abundant amine carriers to facilitate the transport of CO 2 through reversible reaction and simultaneously improved the filler–polymer interface compatibility. The membranes were characterized by scanning electron microscopy (SEM), differential scanning calorimetry (DSC), tensile test, dynamic mechanical analysis (DMA), and X-ray diffraction (XRD). The results indicated that incorporation of PEI-MCM-41 generated stronger interfacial interactions and resulted in higher polymer chain rigidification at the filler–polymer interface compared with unmodified MCM-41. The as-prepared FT-MMMs showed increased gas permeability and selectivity, and the highest ideal selectivities for CO 2 /CH 4 and CO 2 /N 2 were 41 and 102 (at a CO 2 permeability of 1521 Barrer), respectively. Compared to the membranes doped with pristine MCM-41, the permeability, the ideal CO 2 /CH 4 selectivity and the ideal CO 2 /N 2 selectivity of the PEI-MCM-41-doped membranes were increased by 102.3%, 115.8% and 96.1%, respectively, at 20 wt% filler loading and surpassed the 2008 Robeson upper bound line.
研究领域:
材料科学
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化学工程
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高影响因子
ACS Sustainable Chemistry & Engineering
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2022
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IF 9.224
Chao Miao,Kaixuan Shang,Lixing Liang,Shumei Chen,Jing Ouyang
In this work, a Ni-based catalyst supported on a core–shell structure catalytic carrier material (Ni/ZSM-5@MCM-41) based on kaolinite tailings is reported, which exhibits excellent CO2 methanation performance at atmospheric pressure. At 400 °C, CO2 conversion and CH4 selectivity reach 80 and 97% with the space velocity of 12,000 mL gcat–1 h–1, respectively, and it can maintain good stability during the 80 h stability test. Compared with traditional Ni/ZSM-5 and Ni/MCM-41 catalysts, Ni/ZSM-5@MCM-41 has more substantial confinement effects on the active components, and the active components are more evenly dispersed on surface of the carrier. In addition, it is confirmed by the in situ diffuse reflectance infrared Fourier transform spectroscopy technique that CO2 methanation over the Ni/ZSM-5@MCM-41 catalyst follows the path of formate and CO as intermediates.
研究领域:
催化
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化学工程
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环境科学
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高影响因子
CHINESE JOURNAL OF CATALYSIS
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2015
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IF 1.964
Dong Xie,Qihui He,Yangyang Su,Tongwei Wang,Renfu Xu,Baixing Hu
Catalysts play an important role in oxidative desulfurization, a promising process for producing cleaner fossil fuels for transport. A highly efficient catalyst, Q 4 -H 2 Se IV 3 W 6 , for the oxidative desulfurization of dibenzothiophene (DBT) was reported in 2011. To comprehensively evaluate this catalyst and better understand its recovery, two types of the catalyst were prepared by impregnating Q 4 -H 2 Se IV 3 W 6 on MCM-41 and functionalized MCM-41 materials. In the oxidative desulfurization process catalyzed by these supported catalysts, the conversion of DBT reached 98.7%. The catalytic activities were excellent when Q 4 -H 2 Se IV 3 W 6 was impregnated on functionalized MCM-41. The results showed that the supported catalysts had excellent reusability. In addition, a mechanism for the catalytic oxidative desulfurization was proposed.
研究领域:
化学工程
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环境科学
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DOI
高影响因子
危险品化学品经营许可证（带存储）