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Light olefins synthesis from С

Anton SHALYGIN, Evgenii PAUKSHTIS, Evgenii KOVALYOV, Bair BAL’ZHINIMAEV

《化学科学与工程前沿(英文)》 2013年 第7卷 第3期   页码 279-288 doi: 10.1007/s11705-013-1338-1

摘要: A two-step process was employed to convert methane or ethane to light olefins via the formation of an intermediate monoalkyl halide. A novel K RuOCl /TiO catalyst was tested for the oxidative chlorination of methane and ethane. The catalyst had high selectivity for methyl and ethyl chlorides, 80% and 90%, respectively. During the oxychlorination of ethane at ≥250°C, the formation of ethylene as a reaction product along with ethyl chloride was observed. In situ Fourier transform infrared studies showed that the key intermediate for monoalkyl chloride and ethylene formation is the alkoxy group. The reaction mechanism for the oxidative chlorination of methane and ethane over the Ru-oxychloride catalyst was proposed. The novel fiber glass catalyst was also tested for the dehydrochlorination of alkyl chlorides to ethylene and propylene. Very high selectivities (up to 94%–98%) for ethylene and propylene formation as well as high stability were demonstrated.

关键词: oxychlorination     methane     ethane     light olefins     ruthenium catalyst    

Effect of temperature in the conversion of methanol to olefins (MTO) using an extruded SAPO-34 catalyst

Ignacio Jorge Castellanos-Beltran, Gnouyaro Palla Assima, Jean-Michel Lavoie

《化学科学与工程前沿(英文)》 2018年 第12卷 第2期   页码 226-238 doi: 10.1007/s11705-018-1709-8

摘要: The methanol-to-olefin (MTO) reaction was investigated in a bench-scale, fixed-bed reactor using an extruded catalyst composed of a commercial SAPO-34 (65 weight percentage, wt-%) embedded in an amorphous SiO matrix (35 wt-%). The texture properties, acidity and crystal structure of the pure SAPO-34 and its extruded form (E-SAPO-34) were analyzed and results indicated that the extrusion step did not affect the properties of the catalyst. Subsequently, E-SAPO-34 was tested in a temperature range between 300 and 500 °C, using an aqueous methanol mixture (80 wt-% water content) fed at a weight hour space velocity (WHSV) of 1.21 h . At 300 °C, a low conversion was observed combined with catalyst deactivation, which was ascribed to oligomerization and condensation reactions. The coke analysis showed the presence of diamandoid hydrocarbons, which are known to be inactive molecules in the MTO process. At higher temperatures, a quasi-steady state was reached during a 6 h reaction where the optimal temperature was identified at 450 °C, which incidentally led to the lowest coke deposition combined with the highest H/C ratio. Above 450 °C, surges of ethylene and methane were associated to a combination of H-transfer and protolytic cracking reactions. Finally, the present work underscored the convenience of the extrusion technique for testing catalysts at simulated scale-up conditions.

关键词: MTO     SAPO-34     temperature     extrusion     coke     light alkanes    

靶向生产低碳烯烃的催化裂化技术——反应机理、生产方案和工艺展望 Review

许友好, Yanfen Zuo, Wenjie Yang, Xingtian Shu, Wei Chen, Anmin Zheng

《工程(英文)》 2023年 第30卷 第11期   页码 100-109 doi: 10.1016/j.eng.2023.02.018

摘要:

Light olefins are important organic building blocks in the chemicals industry. The main low-carbon olefin production methods, such as catalytic cracking and steam cracking, have considerable room for improvement in their utilization of hydrocarbons. This article provides a thorough overview of recent studies on catalytic cracking, steam cracking, and the conversion of crude oil processes. To maximize the production of light olefins and reduce carbon emissions, the perceived benefits of various technologies are examined. Taking olefin generation and conversion as a link to expand upstream and downstream processes, a targeted catalytic cracking to olefins (TCO) process is proposed to meet current demands for the transformation of oil refining into chemical production. The main innovations of this process include a multiple feedstock supply, the development of medium-sized catalysts, and a diameter-transformed fluidized-bed reactor with different feeding schemes. In combination with other chemical processes, TCO is expected to play a critical role in enabling petroleum refining and chemical processes to achieve low carbon dioxide emissions.

关键词: Light olefins     Steam cracking     Catalytic cracking     TCO process     Oil processing revolution    

Selective epoxidation of linear terminal olefins with metalloporphyrins under mild conditions

Xiaoguang BAI, Yuanbin SHE

《化学科学与工程前沿(英文)》 2009年 第3卷 第3期   页码 310-313 doi: 10.1007/s11705-009-0168-7

摘要: The epoxidation of linear terminal olefins with metalloporphyrins in the presence of dioxygen and isobutyraldehyde under ambient temperature and atmospheric pressure was investigated. The results show that all olefins could be smoothly converted to epoxides with high selectivities (70%-90%). For the metalloporphyrins with different catalytic activities within 1-hexene epoxidation in the order of Fe>Mn>Co, T( -Cl)PPFe(Ⅲ)Cl was most effective, with a 41.7% yield and 80.2% selectivity of 1,2-epoxyhexane. Various amounts of catalyst were investigated, and it was found that with only 10 ppm catalyst the yield of 1,2-epoxyhexane and turnover number (TON) could reach up to 41.9% and 41859, respectively.

关键词: metalloporphyrins     olefins     dioxygen     epoxidation    

Confinement effects in methanol to olefins catalysed by zeolites: A computational review

German Sastre

《化学科学与工程前沿(英文)》 2016年 第10卷 第1期   页码 76-89 doi: 10.1007/s11705-016-1557-3

摘要: Small pore zeolites, containing 8-rings as the largest, are widely employed as catalysts in the process of methanol-to-olefins (MTO). Reactants and products diffuse with constraints through 8-rings and this is one of the reaction bottlenecks related to zeolite micropore topology. Small pore zeolites and silicon-aluminophosphates(SAPOs) containing cavities, where olefins are mainly formed through the hydrocarbon pool (HP) mechanism, are frequently tested for MTO. Shape selectivity of transition states within the side-chain methylation will be reviewed as this is one of the controlling steps of the MTO process, with particular attention to the role of hexamethylbenzene (HMB) and heptamethylbenzenium cation (HeptaMB ), which are the most tipically detected reaction intermediates, common to the paring and side-chain routes within the HP mechanism. The relative stability of these and other species will be reviewed in terms of confinement effects in different cage-based zeolites. The role of the different alkylating agents, methanol, dimethyl ether (DME), and surface methoxy species (SMS) will also be reviewed from the computational viewpoint.

关键词: small pore zeolites     SAPOs     methanol-to-olefins     hydrocarbon pool mechanism     alkylation of polymethylbenzenes    

Benzene alkylation with long chain olefins catalyzed by ionic liquids: a review

QIAO Congzhen, CAI Yonghong, GUO Quanhui

《化学科学与工程前沿(英文)》 2008年 第2卷 第3期   页码 346-352 doi: 10.1007/s11705-008-0045-9

摘要: The introduction of ionic liquids to alkylation process gives a choice for “green production” in the petrochemical and detergent industry. A lot of papers and patents have been published using chloroaluminate ionic liquid as a novel catalyst for alkylation with high reactivity and easy separation from reactants. These included the acidity, characterization, determination and catalysis technologies in batch and continuous operation mode for different scales. According to published data and several results of pilot alkylation,including the authors’ experience,the prospect of chloroaluminate ionic liquids for commercials was also discussed. It has been pointed out that there still are many difficulties and challenges to be overcome for commercial application of the ionic liquid catalyst.

关键词: different     petrochemical     characterization     introduction     chloroaluminate    

Continuous reaction performances of benzene alkylation with long chain olefins catalyzed by ionic liquid

QIAO Congzhen, LI Chengyue

《化学科学与工程前沿(英文)》 2008年 第2卷 第1期   页码 69-73 doi: 10.1007/s11705-008-0014-3

摘要: Based on a compulsive mixing-reacting-separating-recycling small experimental setup,the continuous reaction performances of benzene alkylation with long chain olefins catalyzed by [BMIM]Cl-AlCl ionic liquid were investigated. Three different situations including normal continuous operation mode (reagent materials), sidetrack feeding from different axial positions along the static mixing reactor (reagent materials) and normal continuous alkylation using industrial paraffin and olefins materials were examined. Even under the relatively hypecritical reaction conditions, the single pass conversion of pure 1-dodecene could reach to nearly 100.0%, and the selectivity of 2-phenyl isomer was higher than 37.7%. Although the positions along the reactor for sidetrack feeding were different, the 100.0% single pass conversion of 1-dodecene was also attained before the outlet of the reactor. The refined industrial olefins as raw material could meet with the requirements of continuous alkylation. The influences of impurities such as di-olefins and non-benzene aromatics on the catalytic activity and stability should be studied further.

关键词: stability     different     hypecritical     compulsive mixing-reacting-separating-recycling     non-benzene    

Photocatalysis: from solar light to hydrogen energy

《能源前沿(英文)》 2021年 第15卷 第3期   页码 565-567 doi: 10.1007/s11708-021-0784-6

A novel light fluctuation spectrum method for in-line particle sizing

Shouxuan QIN, Xiaoshu CAI, Li MA

《能源前沿(英文)》 2012年 第6卷 第1期   页码 89-97 doi: 10.1007/s11708-012-0176-z

摘要: This paper discusses two problems in in-line particle sizing when using light fluctuation method. First, by retrieving the ratio of particle concentrations at different time, the intensity of incident light is obtained. There exists narrow error between the calculated and pre-detected value of the intensity of incident light. Secondly, by combining spectrum analysis with Gregory’s theory, a multi-sub-size zone model is proposed, with which the relationship between the distribution of turbidity and the particle size distribution (PSD) can be established, and an algorithm developed to determine the distribution of turbidity. Experiments conducted in the laboratory indicate that the measured size distribution of pulverized coal conforms well with the imaging result.

关键词: in-line measurement     particle size distribution (PSD)     incident light intensity     particle concentration     light fluctuation    

surfactant-assisted synthesis of mesoporous SSZ-39 zeolite with enhanced catalytic performance in the methanol-to-olefins

Hao Xu, Chi Lei, Qinming Wu, Qiuyan Zhu, Xiangju Meng, Daniel Dai, Stefan Maurer, Andrei-Nicolae Parvulescu, Ulrich Müller, Fengshou Xiao

《化学科学与工程前沿(英文)》 2020年 第14卷 第2期   页码 267-274 doi: 10.1007/s11705-019-1845-9

摘要: SSZ-39 zeolite with AEI framework structure is a good catalyst candidate for the methanol-to-olefins (MTO) reaction. However, the diffusion limitation and coke formation often results in fast deactivation of the SSZ-39 zeolite catalyst. One solution for this challenge is to introduce mesoporosity in the SSZ-39 zeolite. Herein, we report the synthesis of mesoporous SSZ-39 zeolite using an organosilane surfactant, , -dimethyl- -(3-(trimethoxysilyl)propyl)octan-1-aminium chloride, as a mesopore template and , -dimethyl- -2,6-dimethylpiperidinium as a micropore template. The obtained zeolites were characterized by X-ray diffraction, N sorption, scanning electron microscopy, temperature programmed desorption of ammonia, and magic angle spinning nuclear magnetic resonance of Al. The results show that the mesoporous SSZ-39 zeolite has high crystallinity, meso/microporosity, high surface area, cuboid morphology, and abundant acidic sites. More importantly, this mesoporous SSZ-39 zeolite exhibits enhanced catalyst lifetime in the MTO reaction due to the presence of mesoporosity for fast mass transfer, compared with a conventional SSZ-39 zeolite without mesoporosity.

关键词: SSZ-39 zeolite     mesopores     organosilane surfactant     MTO reaction     soft template     mass transfer    

Plasmonic light trapping for enhanced light absorption in film-coupled ultrathin metamaterial thermophotovoltaic

Qing NI, Hassan ALSHEHRI, Yue YANG, Hong YE, Liping WANG

《能源前沿(英文)》 2018年 第12卷 第1期   页码 185-194 doi: 10.1007/s11708-018-0522-x

摘要: Ultrathin cells have gained increasing attention due to their potential for reduced weight, reduced cost and increased flexibility. However, the light absorption in ultrathin cells is usually very weak compared to the corresponding bulk cells. To achieve enhanced photon absorption in ultrathin thermophotovoltaic (TPV) cells, this work proposed a film-coupled metamaterial structure made of nanometer-thick gallium antimonide (GaSb) layer sandwiched by a top one-dimensional (1D) metallic grating and a bottom metal film. The spectral normal absorptance of the proposed structure was calculated using the rigorous coupled-wave algorithm (RCWA) and the absorption enhancement was elucidated to be attributed to the excitations of magnetic polariton (MP), surface plasmon polariton (SPP), and Fabry-Perot (FP) resonance. The mechanisms of MP, SPP, and FP were further confirmed by an inductor-capacitor circuit model, dispersion relation, and phase shift, respectively. Effects of grating period, width, spacer thickness, as well as incidence angle were discussed. Moreover, short-circuit current density, open-circuit voltage, output electric power, and conversion efficiency were evaluated for the ultrathin GaSb TPV cell with a film-coupled metamaterial structure. This work will facilitate the development of next-generation low-cost ultrathin infrared TPV cells.

关键词: metamaterial     thermophotovoltaic     plasmonics     light trapping     selective absorption    

HQ in inland saline-alkaline water under different light qualities

《环境科学与工程前沿(英文)》 2022年 第16卷 第4期 doi: 10.1007/s11783-021-1479-2

摘要:

• Optimal growth of Chlorella in inland saline-alkaline water was achieved by blue LED.

关键词: Light quality     Chlorella     Inland saline-alkaline water     Fatty acid     Biodiesel property    

Effect of light scattering on the performance of a direct absorption solar collector

Kwang Hyun WON, Bong Jae LEE

《能源前沿(英文)》 2018年 第12卷 第1期   页码 169-177 doi: 10.1007/s11708-018-0527-5

摘要: Recently, a solar thermal collector often employs nanoparticle suspension to absorb the solar radiation directly by a working fluid as well as to enhance its thermal performance. The collector efficiency of a direct absorption solar collector (DASC) is very sensitive to optical properties of the working fluid, such as absorption and scattering coefficients. Most of the existing studies have neglected particle scattering by assuming that the size of nanoparticle suspension is much smaller than the wavelength of solar radiation (i.e., Rayleigh scattering is applicable). If the nanoparticle suspension is made of metal, however, the scattering cross-section of metallic nanoparticles could be comparable to their absorption cross-section depending on the particle size, especially when the localized surface plasmon (LSP) is excited. Therefore, for the DASC utilizing a plasmonic nanofluid supporting the LSP, light scattering from metallic particle suspension must be taken into account in the thermal analysis. The present study investigates the scattering effect on the thermal performance of the DASC employing plasmonic nanofluid as a working fluid. In the analysis, the Monte Carlo method is employed to numerically solve the radiative transfer equation considering the volume scattering inside the nanofluid. It is found that the light scattering can improve the collector performance if the scattering coefficient of nanofluid is carefully engineered depending on its value of the absorption coefficient.

关键词: direct absorption solar collector     plasmonic nanofluid     light scattering    

甲醇制烯烃技术——DMTO技术

叶茂, 田鹏, 刘中民

《工程(英文)》 2021年 第7卷 第1期   页码 17-21 doi: 10.1016/j.eng.2020.12.001

关键词: 工程成就    

Lignin-derived dual-function red light carbon dots for hypochlorite detection and anti-counterfeiting

《化学科学与工程前沿(英文)》 2023年 第17卷 第7期   页码 966-975 doi: 10.1007/s11705-022-2244-1

摘要: The efficient utilization of natural lignin, which is the main by-product of the cellulose industry, is crucial for enhancing its economic value, alleviating the environmental burden, and improving ecological security. By taking advantage of the large sp2 hybrid domain of lignin and introducing amino functional groups, new lignin-derived carbon dots (SPN-CDs) with red fluorescence were successfully synthesized. Compared with green and blue fluorescent materials, red SPN-CDs have desirable anti-interference properties of short-wave background and exhibit superior luminescence stability. The SPN-CDs obtained exhibited sensitive and distinctive visible color with fluorescence-dual responses toward hypochlorite. Considering this feature, a portable, low-cost, and sensitive fluorescence sensing paper with a low limit of detection of 0.249 μmol∙L–1 was fabricated using the SPN-CDs for hypochlorite detection. Furthermore, a new type of visible-light and fluorescence dual-channel information encryption platform was constructed. Low-concentration hypochlorite can be employed as an accessible and efficient information encryption/decryption stimulus, as well as an information “eraser”, facilitating a safe and diversified transmission and convenient decryption of information. This work opens new avenues for high-value-added applications of lignin-based fluorescent materials.

关键词: alkali lignin     red light carbon dots     hypochlorite     encryption and anti-counterfeiting    

标题 作者 时间 类型 操作

Light olefins synthesis from С

Anton SHALYGIN, Evgenii PAUKSHTIS, Evgenii KOVALYOV, Bair BAL’ZHINIMAEV

期刊论文

Effect of temperature in the conversion of methanol to olefins (MTO) using an extruded SAPO-34 catalyst

Ignacio Jorge Castellanos-Beltran, Gnouyaro Palla Assima, Jean-Michel Lavoie

期刊论文

靶向生产低碳烯烃的催化裂化技术——反应机理、生产方案和工艺展望

许友好, Yanfen Zuo, Wenjie Yang, Xingtian Shu, Wei Chen, Anmin Zheng

期刊论文

Selective epoxidation of linear terminal olefins with metalloporphyrins under mild conditions

Xiaoguang BAI, Yuanbin SHE

期刊论文

Confinement effects in methanol to olefins catalysed by zeolites: A computational review

German Sastre

期刊论文

Benzene alkylation with long chain olefins catalyzed by ionic liquids: a review

QIAO Congzhen, CAI Yonghong, GUO Quanhui

期刊论文

Continuous reaction performances of benzene alkylation with long chain olefins catalyzed by ionic liquid

QIAO Congzhen, LI Chengyue

期刊论文

Photocatalysis: from solar light to hydrogen energy

期刊论文

A novel light fluctuation spectrum method for in-line particle sizing

Shouxuan QIN, Xiaoshu CAI, Li MA

期刊论文

surfactant-assisted synthesis of mesoporous SSZ-39 zeolite with enhanced catalytic performance in the methanol-to-olefins

Hao Xu, Chi Lei, Qinming Wu, Qiuyan Zhu, Xiangju Meng, Daniel Dai, Stefan Maurer, Andrei-Nicolae Parvulescu, Ulrich Müller, Fengshou Xiao

期刊论文

Plasmonic light trapping for enhanced light absorption in film-coupled ultrathin metamaterial thermophotovoltaic

Qing NI, Hassan ALSHEHRI, Yue YANG, Hong YE, Liping WANG

期刊论文

HQ in inland saline-alkaline water under different light qualities

期刊论文

Effect of light scattering on the performance of a direct absorption solar collector

Kwang Hyun WON, Bong Jae LEE

期刊论文

甲醇制烯烃技术——DMTO技术

叶茂, 田鹏, 刘中民

期刊论文

Lignin-derived dual-function red light carbon dots for hypochlorite detection and anti-counterfeiting

期刊论文