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Catalytic fast pyrolysis of Kraft lignin with HZSM-5 zeolite for producing aromatic hydrocarbons

Xiangyu LI, Lu SU, Yujue WANG, Yanqing YU, Chengwen WANG, Xiaoliang LI, Zhihua WANG

《环境科学与工程前沿（英文）》 2012年 第6卷 第3期   页码 295-303 doi: 10.1007/s11783-012-0410-2

摘要： Catalytic fast pyrolysis (CFP) of Kraft lignins with HZSM-5 zeolite for producing aromatics was investigated using analytical pyrolysis methods. Two Kraft lignins were fast pyrolyzed in the absence and presence of HZSM-5 in a Curie-point pyrolyzer. Without the catalyst, fast pyrolysis of lignin predominantly produced phenols and guaiacols that were derived from the subunits of lignin. However, the presence of HZSM-5 changed the product distribution dramatically. As the SiO /Al O ratio of HZSM-5 decreased from 200 to 25 and the catalyst-to-lignin ratio increased from 1 to 20, the lignin-derived oxygenates progressively decreased to trace and the aromatics increased substantially. The aromatic yield increased considerably as the pyrolysis temperature increased from 500°C to 650°C, but then decreased with yet further increase of pyrolysis temperature. Under optimal reaction conditions, the aromatic yields were 2.0 wt.% and 5.2 wt.% for the two lignins that had effective hydrogen indexes of 0.08 and 0.35.

关键词： lignin     catalytic fast pyrolysis     HZSM-5     zeolite     aromatic hydrocarbon    

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Catalytic hydrogenation of insoluble organic matter of CS/Acetone from coal over mesoporous HZSM-5 supported

《化学科学与工程前沿（英文）》 2022年 第16卷 第10期   页码 1505-1513 doi: 10.1007/s11705-022-2164-0

摘要： Four supported catalysts, nickel and ruthenium on a HZSM-5 support, were prepared by equal volume impregnation and in-situ decomposition of carbonyl nickel. The properties of catalysts were investigated by catalytic hydro-conversion of 2,2′-dinaphthyl ether as the model compound and extraction residue of Naomaohu lignite as the sample under an initial H2 pressure of 5 MPa and temperature at 150 °C. According to the catalytic hydro-conversion results of the model compound, Ni−Ru/HZSM-5 exhibited the best catalytic performance. It not only activated H2 into H···H, but also further heterolytically split H···H into immobile H‒ attached on the acidic centers of Ni−Ru/HZSM-5 and relatively mobile H+. Catalytic hydro-conversion of the extraction residue from Naomaohu lignite was further examined over the optimized catalyst, Ni−Ru/HZSM-5. Detailed molecular compositions of products from the extraction residue with and without hydrogenation were characterized by Fourier transform infrared spectroscopy and gas chromatography/mass spectrometry. The analytical results showed that the oxygen-containing functional groups in products of hydrogenated extraction residue were obviously reduced after the catalytic treatment. The relative content of oxygenates in the product with catalytic treatment was 18.57% lower than that in the product without catalytic treatment.

关键词： HZSM-5     Ni-based catalyst     catalytic hydrogenation     coal     model compound    

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Fast and catalytic pyrolysis of xylan: Effects of temperature and M/HZSM-5 (M= Fe, Zn) catalysts on pyrolytic

Xifeng ZHU, Qiang LU, Wenzhi LI, Dong ZHANG,

《能源前沿（英文）》 2010年 第4卷 第3期   页码 424-429 doi: 10.1007/s11708-010-0015-z

摘要： Pyrolysis-gas chromatography/mass spectrometry (Py-GC/MS) was employed to achieve fast pyrolysis of xylan and on-line analysis of pyrolysis vapors. Tests were conducted to investigate the effects of temperature on pyrolytic products, and to reveal the effect of HZSM-5 and M/HZSM-5 (M= Fe, Zn) zeolites on pyrolysis vapors. The results showed that the total yield of pyrolytic products first increased and then decreased with the increase of temperature from 350°C to 900°C. The pyrolytic products were complex, and the most abundant products included hydroxyacetaldehyde, acetic acid, 1-hydroxy-2-propanone, 1-hydroxy-2-butanone and furfural. Catalytic cracking of pyrolysis vapors with HZSM-5 and M/HZSM-5 (M= Fe, Zn) catalysts significantly altered the product distribution. Oxygen-containing compounds were reduced considerably, and meanwhile, a lot of hydrocarbons, mainly toluene and xylenes, were formed. M/HZSM-5 catalysts were more effective than HZSM-5 in reducing the oxygen-containing compounds, and therefore, they helped to produce higher contents of hydrocarbons than HZSM-5.

关键词： xylan     fast pyrolysis     catalytic pyrolysis     Py-GC/MS     HZSM-5    

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Modification of acidity of Mo-Fe/HZSM-5 zeolite via argon plasma treatment

ZHU Xinli, YU Kailu, CHENG Dangguo, XIA Qing, LIU Changjun, ZHANG Yueping

《化学科学与工程前沿（英文）》 2008年 第2卷 第1期   页码 55-58 doi: 10.1007/s11705-008-0005-4

摘要： The NH-TPD characterization was conducted to confirm that the acidity of Mo-Fe/HZSM-5 zeolite could be selectively modified via the glow discharge plasma treatment. The plasma catalyst treatment could totally change the distribution of aromatic products with higher methane conversion compared to the untreated catalyst. Some polycyclic aromatics such as anthracene, pyrene and phenanthrene were also produced over the plasma treated catalyst, in addition to benzene, toluene and naphthalene, which were normally obtained over the untreated catalyst.

关键词： phenanthrene     Mo-Fe/HZSM-5     conversion     glow discharge     polycyclic    

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ZnZr/HZSM-5 as efficient catalysts for alkylation of benzene with carbon dioxide

《化学科学与工程前沿（英文）》 2023年 第17卷 第4期   页码 404-414 doi: 10.1007/s11705-022-2215-6

摘要： Alkylation of benzene with carbon dioxide and hydrogen to produce toluene and xylene could increase the added-value of surplus benzene as well as relieve environmental problems like green-house effect. In this work, the alkylation benzene with carbon dioxide and hydrogen reaction was proceeded by using the mixture of zinc-zirconium oxide and HZSM-5 as bifunctional catalyst. The equivalent of Zn/Zr = 1 displays the best catalytic performance at 425 °C and 3.0 MPa, and benzene conversion reaches 42.9% with a selectivity of 90% towards toluene and xylene. Moreover, the carbon dioxide conversion achieves 23.3% and the carbon monoxide selectivity is lower than 35%, indicating that more than 50% carbon dioxide has been effectively incorporated into the target product, which is the best result as far as we know. Combined with characterizations, it indicated that the Zn and Zr formed a solid solution under specific conditions (Zn/Zr = 1). The as-formed solid solution not only possesses a high surface area but also provides a large amount of oxygen vacancies. Additionally, the bifunctional catalyst has excellent stabilities that could keep operating without deactivation for at least 80 h. This work provides promising industrial applications for the upgrading of aromatics.

关键词： carbon dioxide     alkylation of benzene     solid solution catalyst     bifunctional catalyst    

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Methanol to propylene: the effect of iridium and iron incorporation on the HZSM-5 catalyst

Alireza MOHAMMADREZAEI, Sadegh PAPARI, Mousa ASADI, Abas NADERIFAR, Reza GOLHOSSEINI

《化学科学与工程前沿（英文）》 2012年 第6卷 第3期   页码 253-258 doi: 10.1007/s11705-012-0902-4

摘要： The effect of iridium and iron impregnation of HZSM-5 zeolite on the methanol to propylene reaction (MTP) was investigated. The selectivities of propylene and other hydrocarbons, and the conversion of methanol were compared by performing MTP in a small pilot plant. The results indicate that HZSM-5 zeolite modified by iron and iridium increased propylene selectivity by 6.3% and 8%, respectively. The selectivity of propylene was higher for Ir/H-ZSM-5 than for Fe/H-ZSM-5, where Fe/H-ZSM-5 was more stable than Ir/H-ZSM-5. Analytic techniques, including X-ray diffraction, BET surface area, temperature-programmed desorption of ammonia, and inductively coupled plasma atomic emission spectroscopy, were used to characterize the modified zeolites as well as the parent zeolites.

关键词： HZSM-5     promoter     iridium     iron     MTP    

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Dealumination and desilication for Al-rich HZSM-5 zeolite via steam-alkaline treatment and its application

Yuehua Fang, Fan Yang, Xuan He, Xuedong Zhu

《化学科学与工程前沿（英文）》 2019年 第13卷 第3期   页码 543-553 doi: 10.1007/s11705-018-1778-8

摘要： The hierarchical HZSM-5 was prepared via dealumination and desilication of commercial Al-rich HZSM-5, and characterized by X-ray diffraction, Al magic-angle spinning nuclear magnetic resonance, inductively coupled plasma mass spectrometry, scanning electron microscope, transmission electron microscope, N adsorption-desorption, NH temperature-programmed desorption, performed thermogravimetric and Raman spectrum. The results showed that partial framework of HZSM-5 was removed after steam treatment at 0.15 MPa, 500°C for 3 h. HZSM-5 with high specific surface area and much mesoporosity was obtained by the subsequent alkaline treatment. The regulation of acid quantity was achieved by altering the concentration of alkaline. Dealumination and desilication of Al-rich HZSM-5 zeolites became more effective using a combination of steam and alkaline treatments than using alkaline treatment alone. Methanol aromatization reaction was employed to evaluate the catalytic performance of treated HZSM-5 at 0.15 MPa, 450°C and MHSV of 1.5 h . The results indicated that after steam treatment, HZSM-5 further treated with 0.2 mol/L NaOH exhibits the best catalytic performance: the selectivity of aromatics reached 42.1% and the lifetime of catalyst attained 212 h, which are much better than untreated HZSM-5.

关键词： steam treatment     alkaline treatment     hierarchical ZSM-5     methanol aromatization    

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Alkylation of benzene with carbon dioxide to low-carbon aromatic hydrocarbons over bifunctional Zn-Ti/HZSM-5-5 catalyst

Xiangyu Liu, Yanling Pan, Peng Zhang, Yilin Wang, Guohao Xu, Zhaojie Su, Xuedong Zhu, Fan Yang

《化学科学与工程前沿（英文）》 2022年 第16卷 第3期   页码 384-396 doi: 10.1007/s11705-021-2045-y

摘要： Alkylation of benzene to value-added, high octane number and low toxic toluene and xylenes provides a way to lower benzene content in gasoline pool, and is hence a method to promote fuel quality. On the other hand, CO accumulation in the atmosphere causes global warming and requires effective route for its valorization. Utilization of CO as a carbon source for benzene alkylation could achieve both goals. Herein, alkylation of benzene with CO and H was realized by a series of low-cost bifunctional catalysts containing zinc/titanium oxides (Zn/Ti oxides) and HZSM-5 molecular sieves in a fixed-bed reactor. By regulating and controlling oxygen vacancies of Zn/Ti oxides and the acidities of HZSM-5, benzene conversion and CO conversion reached 28.7% and 29.9% respectively, along with a total selectivity of toluene and xylene higher than 90%. In this process, more than 25% CO was effectively utilized and incorporated into the target products. Moreover, the mechanism of the reaction was analyzed and the course was simultaneously traced. CO was transformed into methanol firstly, and then methanol reacted with benzene generating toluene and xylene. The innovation provides a new method for upgrading of fuels and upcycling the emissions of CO , which is of great environmental and economic benefits.

关键词： carbon dioxide     benzene     alkylation     bifunctional catalyst     mechanism    

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On the monolayer dispersion behavior of Co3O4 on HZSM-5 support: designing applicable

《化学科学与工程前沿（英文）》 2023年 第17卷 第11期   页码 1741-1754 doi: 10.1007/s11705-023-2332-x

摘要： Based on monolayer dispersion theory, Co3O4/ZSM-5 catalysts with different loadings have been prepared for selective catalytic reduction of nitrogen oxides by ammonia. Co3O4 can spontaneously disperse on HZSM-5 support with a monolayer dispersion threshold of 0.061 mmol 100 m–2, equaling to a weight percentage around 4.5%. It has been revealed that the quantities of surface active oxygen (O2–) and acid sites are crucial for the reaction, which can adsorb and activate NOx and NH3 reactants effectively. Below the monolayer dispersion threshold, Co3O4 is finely dispersed as sub-monolayers or monolayers and in an amorphous state, which is favorable to generate the two kinds of active sites, hence promoting the performance of ammonia selective catalytic reduction of nitrogen oxide. However, the formation of crystalline Co3O4 above the capacity is harmful to the reaction performance. 4% Co3O4/ZSM-5, the catalyst close to the monolayer dispersion capacity, possesses the most abundant active O2– species and acidic sites, thereby demonstrating the best reaction performance in all the samples. It is proposed the optimal Co3O4/ZSM-5 catalyst can be prepared by loading the capacity amount of Co3O4 onto HZSM-5 support.

关键词： Co3O4/ZSM-5     NOx-SCR by NH3     monolayer dispersion threshold effect     surface acid sites     surface active O2– anions    

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Catalytic cracking of endothermic fuels in coated tube reactor

LI Jia, ZOU Jijun, ZHANG Xiangwen, GUO Wei, MI Zhentao

《化学科学与工程前沿（英文）》 2008年 第2卷 第2期   页码 181-185 doi: 10.1007/s11705-008-0032-1

摘要： Suspensoid of HZSM-5 or HY zeolites mixed with a self-made ceramic-like binder was coated on the inner wall of a tubular reactor by gas-aided fluid displacement technology. The coated zeolites were characterized by means of X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR) and scanning electron microscopy (SEM). The coating thickness is 10–20 ?m and the particle size of the zeolites is in the range of 1–5 ?m. In the coated reactor, cracking of endothermic fuels including -dodecane and aviation fuel RP-3 was carried out separately under supercritical conditions at 600°C and 625°C to investigate their heat sinks and conversion of catalytic reactions. For the reaction catalyzed by HY(25% mass fraction) coating, the heat sink capacity of -dodecane are 815.7 and 901.9 kJ/kg higher than that of the bare tube at 600°C and at 625°C, respectively. Conversion of -dodecane also increases from 42% to 60% at 600°C and from 66% to 80% at 625°C. The coated zeolite can significantly inhibit the carbon deposition during supercritical cracking reactions.

关键词： HZSM-5     self-made ceramic-like     gas-aided     Conversion     Suspensoid    

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Effect of SiO

Qian WANG, Lei WANG, Hui WANG, Zengxi LI, Xiangping ZHANG, Suojiang ZHANG, Kebin ZHOU

《化学科学与工程前沿（英文）》 2011年 第5卷 第1期   页码 79-88 doi: 10.1007/s11705-010-0550-5

摘要： A series of SAPO-34 molecular sieves with different SiO /Al O ratios have been synthesized for the methanol-to-olefin (MTO) reaction. Their physico-chemical properties are characterized by various techniques such as X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), Fourier transform infrared spectroscopy (FT-IR) and N adsorption-desorption. The results are compared with those of the commercial HZSM-5, which show that the crystallinity and particle diameter of SAPO-34 as well as HZSM-5 increase with SiO /Al O ratio. The variation of BET surface area of SAPO-34 is different from that of HZSM-5 and the sample with SiO /Al O ratio of 0.4 exhibits the highest BET surface area. FT-IR spectra indicate that HZSM-5 has both Br?nsted and Lewis acid sites and Br?nsted acid sites are stronger, whereas SAPO-34 samples are dominated only by Lewis acid sites. When the SiO /Al O ratio increases, propylene and butylenes become the predominant product of the MTO reaction over HZSM-5. In contrast, the main products of this reaction catalyzed by SAPO-34 are ethylene and propylene. According to the product distribution, the reaction mechanism over HZSM-5 catalysts is proposed.

关键词： HZSM-5     SAPO-34     methanol-to-olefin (MTO)     SiO2/Al2O3 ratio    

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5G成效未达预期

Mitch Leslie

《工程（英文）》 2023年 第29卷 第10期   页码 5-7 doi: 10.1016/j.eng.2023.08.003

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基于 5G技术的教育信息化应用研究

卢向群,孙禹

《中国工程科学》 2019年 第21卷 第6期   页码 120-128 doi: 10.15302/J-SSCAE-2019.06.020

摘要：

教育信息化日益普及，智慧学习空间不断出现，学生对学习内容的个性化、便捷化、多样化需求也日益凸显，而第五代移动通信（ 5G）技术以其大带宽、本文重点探索 5G技术的教育信息化应用，在梳理教育信息化主要特征的基础上，分析了我国教育网络面临的技术挑战，从教学、教研、教育管理三方面着手，论证提出相应的 5G应用场景，形成 5G教育信息化总体视图。面向 2035年， 5G的技术普及与应用拓展，将不断丰富教育场景的内涵，推动教育场景的变革，成为我国教育信息化创新的原生动力。

关键词： 教育     信息技术     教育信息化     5G 技术     应用场景    

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5G应用下的MIMO阵列天线去耦方法综述 Review Articles

Xiao-xi ZHANG, Ai-di REN, Ying LIU

《信息与电子工程前沿（英文）》 2020年 第21卷 第1期   页码 62-71 doi: 10.1631/FITEE.1900466

摘要： 提出一种面向微纳卫星的自主汽化管理液氨推进系统。相比常规冷气或液化气推进系统，提出多路平行筛孔式汽化装置和对应汽化控制方法。所提方案有效解决了液氨高汽化潜热和不易完全汽化的问题，从而发挥液氨推进剂高贮存密度和高比冲性能优势。此外，重点分析自主汽化管理液氨推进系统的工作流程及其涉及的物理化学过程和数学模型。综合考虑推力表现和能源效率，提出最优系统推力控制策略。地面测试表明，自主汽化管理液氨推进系统总重1.8 kg（包含0.34 kg液氨推进剂），比冲达到100 s，系统功耗在10 W以下。自主汽化管理液氨推进系统具有高比冲、低功耗、可实现性强、推力输出均一稳定等特点，适合微纳卫星在轨应用。

关键词： MIMO阵列；5G手机；去耦方法    

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lncR-GAS5 upregulates the splicing factor to impair endothelial autophagy, leading to atherogenesis

《医学前沿（英文）》 2023年 第17卷 第2期   页码 317-329 doi: 10.1007/s11684-022-0931-4

摘要： Long noncoding RNAs (lncRNAs) play a critical role in the regulation of atherosclerosis. Here, we investigated the role of the lncRNA growth arrest-specific 5 (lncR-GAS5) in atherogenesis. We found that the enforced expression of lncR-GAS5 contributed to the development of atherosclerosis, which presented as increased plaque size and reduced collagen content. Moreover, impaired autophagy was observed, as shown by a decreased LC3II/LC3I protein ratio and an elevated P62 level in lncR-GAS5-overexpressing human aortic endothelial cells. By contrast, lncR-GAS5 knockdown promoted autophagy. Moreover, serine/arginine-rich splicing factor 10 (SRSF10) knockdown increased the LC3II/LC3I ratio and decreased the P62 level, thus enhancing the formation of autophagic vacuoles, autolysosomes, and autophagosomes. Mechanistically, lncR-GAS5 regulated the downstream splicing factor SRSF10 to impair autophagy in the endothelium, which was reversed by the knockdown of SRSF10. Further results revealed that overexpression of the lncR-GAS5-targeted gene miR-193-5p promoted autophagy and autophagic vacuole accumulation by repressing its direct target gene, SRSF10. Notably, miR-193-5p overexpression decreased plaque size and increased collagen content. Altogether, these findings demonstrate that lncR-GAS5 partially contributes to atherogenesis and plaque instability by impairing endothelial autophagy. In conclusion, lncR-GAS5 overexpression arrested endothelial autophagy through the miR-193-5p/SRSF10 signaling pathway. Thus, miR-193-5p/SRSF10 may serve as a novel treatment target for atherosclerosis.

关键词： lncR-GAS5     miR-193-5p     splicing factor SRSF10     autophagy     atherogenesis    

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标题 作者 时间 类型 操作

Catalytic fast pyrolysis of Kraft lignin with HZSM-5 zeolite for producing aromatic hydrocarbons

Xiangyu LI, Lu SU, Yujue WANG, Yanqing YU, Chengwen WANG, Xiaoliang LI, Zhihua WANG

期刊论文

Catalytic hydrogenation of insoluble organic matter of CS/Acetone from coal over mesoporous HZSM-5 supported

期刊论文

Fast and catalytic pyrolysis of xylan: Effects of temperature and M/HZSM-5 (M= Fe, Zn) catalysts on pyrolytic

Xifeng ZHU, Qiang LU, Wenzhi LI, Dong ZHANG,

期刊论文

Modification of acidity of Mo-Fe/HZSM-5 zeolite via argon plasma treatment

ZHU Xinli, YU Kailu, CHENG Dangguo, XIA Qing, LIU Changjun, ZHANG Yueping

期刊论文

ZnZr/HZSM-5 as efficient catalysts for alkylation of benzene with carbon dioxide

期刊论文

Methanol to propylene: the effect of iridium and iron incorporation on the HZSM-5 catalyst

Alireza MOHAMMADREZAEI, Sadegh PAPARI, Mousa ASADI, Abas NADERIFAR, Reza GOLHOSSEINI

期刊论文

Dealumination and desilication for Al-rich HZSM-5 zeolite via steam-alkaline treatment and its application

Yuehua Fang, Fan Yang, Xuan He, Xuedong Zhu

期刊论文

Alkylation of benzene with carbon dioxide to low-carbon aromatic hydrocarbons over bifunctional Zn-Ti/HZSM-5-5 catalyst

Xiangyu Liu, Yanling Pan, Peng Zhang, Yilin Wang, Guohao Xu, Zhaojie Su, Xuedong Zhu, Fan Yang

期刊论文

On the monolayer dispersion behavior of Co3O4 on HZSM-5 support: designing applicable

期刊论文

Catalytic cracking of endothermic fuels in coated tube reactor

LI Jia, ZOU Jijun, ZHANG Xiangwen, GUO Wei, MI Zhentao

期刊论文

Effect of SiO

Qian WANG, Lei WANG, Hui WANG, Zengxi LI, Xiangping ZHANG, Suojiang ZHANG, Kebin ZHOU

期刊论文

5G成效未达预期

Mitch Leslie

期刊论文

基于 5G技术的教育信息化应用研究

卢向群,孙禹

期刊论文

5G应用下的MIMO阵列天线去耦方法综述

Xiao-xi ZHANG, Ai-di REN, Ying LIU

期刊论文

lncR-GAS5 upregulates the splicing factor to impair endothelial autophagy, leading to atherogenesis

期刊论文