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New nanostructured sorbents for desulfurization of natural gas

Lifeng WANG, Ralph T. YANG

《化学科学与工程前沿(英文)》 2014年 第8卷 第1期   页码 8-19 doi: 10.1007/s11705-014-1411-4

摘要: Desulfurization of natural gas is achieved commercially by absorption with liquid amine solutions. Adsorption technology could potentially replace the solvent extraction process, particularly for the emerging shale gas wells with production rates that are generally lower than that from the large conventional reservoirs, if a superior adsorbent (sorbent) is developed. In this review, we focus our discussion on three types of sorbents: metal-oxide based sorbents, Cu/Ag-based and other commercial sorbents, and amine-grafted silicas. The advantages and disadvantages of each type are analyzed. Possible approaches for future developments to further improve these sorbents are suggested, particularly for the most promising amine-grafted silicas.

关键词: desulfurization     natural gas desulfurization     hydrogen sulfide sorbent     amine-silica sorbent    

Reaction and characterization of crosslinking hyperbranched poly (amine-ester) with succine anhydride

XIAO Ling, WEI Xiuzhen, ZHU Baoku

《化学科学与工程前沿(英文)》 2007年 第1卷 第4期   页码 355-359 doi: 10.1007/s11705-007-0064-y

摘要: Basing on hydroxyl terminated hyperbranched poly (amine-ester)s (HPAEs), the cross-linking reactions and preparation of ester-crosslinked HPAE films were investigated using succine anhydride (SA) as crosslink reagent. It was proved that the cross-linking reaction between HPAE and SA followed a two-step mechanism. This mechanism provides an efficient route to prepare HPAE/SA cross-linked films, in which, the precursor films were prepared by casting HPAE/SA solution at a lower temperature, and then curing the films at a higher temperature. By varying SA content, the solid HPAE/SA films with different cross-linking degrees were prepared successfully. The highest tensile strength of the cross-linked film could reach 59.60 MPa. With all water contact angle smaller than 74.3°, the crosslinked films demonstrated good hydrophilic properties.

关键词: different cross-linking     amine-ester     temperature     crosslinked     efficient    

Preparation and selection of Fe-Cu sorbent for COS removal in syngas

Bowu CHENG, Zhaofei CAO, Yong BAI, Dexiang ZHANG

《化学科学与工程前沿(英文)》 2010年 第4卷 第4期   页码 441-444 doi: 10.1007/s11705-010-0507-8

摘要: A series of iron-based sorbents prepared with iron trioxide hydrate, cupric oxide by a novel method was studied in a fixed-bed reactor for COS removal from syngas at moderate temperature. In addition, the sorbents mixed with various additives in different ratios were tested. The effects of additive type and ratio on the breakthrough capacity and desulfurization performance, as well as the influence of operating conditions on sulfidation behavior of the sorbent, were investigated. The simulate gas contained 1% COS, 5% CO , 20%–30% CO and 60%–70% H . The outlet gases from the fixed-bed reactor were automatically analyzed by on-line mass spectrometry, and the COS concentration before breakthrough can be kept steady at 1 ppmv. The result shows that the breakthrough sulfur capacity of the sorbent is as high as 25 g-S/100 g. At 700 K and space velocity of 1000 h , the efficiency of sulfur removal and breakthrough sulfur capacity of the sorbent increase with the increase of copper oxide with an optimum value. The result shows that the species and content of additives also affect desulfurization performance of the sorbent.

关键词: sorbent     desulfurization     COS removal     syngas    

Activated carbons and amine-modified materials for carbon dioxide capture –– a review

Zhenhe CHEN, Shubo DENG, Haoran WEI, Bin WANG, Jun HUANG, Gang YU

《环境科学与工程前沿(英文)》 2013年 第7卷 第3期   页码 326-340 doi: 10.1007/s11783-013-0510-7

摘要: Rapidly increasing concentration of CO in the atmosphere has drawn more and more attention in recent years, and adsorption has been considered as an effective technology for CO capture from the anthropogenic sources. In this paper, the attractive adsorbents including activated carbons and amine-modified materials were mainly reviewed and discussed with particular attention on progress in the adsorbent preparation and CO adsorption capacity. Carbon materials can be prepared from different precursors including fossil fuels, biomass and resins using the carbonization-activation or only activation process, and activated carbons prepared by KOH activation with high CO adsorbed amount were reviewed in the preparation, adsorption capacity as well as the relationship between the pore characteristics and CO adsorption. For the amine-modified materials, the physical impregnation and chemical graft of polyethylenimine (PEI) on the different porous materials were introduced in terms of preparation method and adsorption performance as well as their advantages and disadvantages for CO adsorption. In the last section, the issues and prospect of solid adsorbents for CO adsorption were summarized, and it is expected that this review will be helpful for the fundamental studies and industrial applications of activated carbons and amine-modified adsorbents for CO capture.

关键词: adsorption capacity     CO2 capture     activated carbon     amine-impregnated adsorbents    

Desulfurization performance of iron-manganese-based sorbent for hot coal gas

Xiurong REN, Weiren BAO, Fan LI, Liping CHANG, Kechang XIE

《化学科学与工程前沿(英文)》 2010年 第4卷 第4期   页码 429-434 doi: 10.1007/s11705-010-0504-y

摘要: A series of iron-manganese-based sorbents were prepared by co-precipitation and physical mixing method, and used for H S removal from hot coal gas. The sulfidation tests were carried out in a fixed-bed reactor with space velocity of 2000 h (STP). The results show that the suitable addition of manganese oxide in iron-based sorbent can decrease H S and COS concentration in exit before breakthrough due to its simultaneous reaction capability with H S and COS. Fe O and MnO are the initial active components in iron-manganese-based sorbent, and FeO and Fe are active components formed by reduction during sulfidation. The crystal phases of iron affect obviously their desulfurization capacity. The reducibility of sorbent changes with the content of MnO in sorbent. S7F3M and S3F7M have bigger sulfur capacities (32.68 and 32.30 gS/100 g total active component), while S5F5M has smaller sulfur capacity (21.92 gS/100 g total active component). S7F3M sorbent has stable sulfidation performance in three sulfidation-regeneration cycles and no apparent structure degradation. The sulfidation performance of iron- manganese-based sorbent is also related with its specific surface area and pore volume.

关键词: iron-manganese-based sorbent     sulfidation performance     regeneration     hot coal gas    

Efficient MgO-doped CaO sorbent pellets for high temperature CO

Zhihong Xu, Tao Jiang, Hao Zhang, Yujun Zhao, Xinbin Ma, Shengping Wang

《化学科学与工程前沿(英文)》 2021年 第15卷 第3期   页码 698-708 doi: 10.1007/s11705-020-1981-2

摘要: Novel MgO-doped CaO sorbent pellets were prepared by gel-casting and wet impregnation. The effect of Na and MgO on the structure and CO adsorption performance of CaO sorbent pellets was elucidated. MgO-doped CaO sorbent pellets with the diameter range of 0.5 1.5 mm exhibited an excellent capacity for CO adsorption and adsorption rate due to the homogeneous dispersion of MgO in the sorbent pellets and its effects on the physical structure of sorbents. The results show that MgO can effectively inhibit the sintering of CaO and retain the adsorption capacity of sorbents during multiple adsorption-desorption cycles. The presence of mesopores and macropores resulted in appreciable change of volume from CaO (16.7 cm ∙mol ) to CaCO (36.9 cm ∙mol ) over repeated operation cycles. Ca2Mg1 sorbent pellets exhibited favorable CO capture capacity (9.49 mmol∙g ), average adsorption rate (0.32 mmol∙g ∙min ) and conversion rate of CaO (74.83%) after 30 cycles.

关键词: MgO doping     CaO sorbent pellets     gel-casting technique     CO2 capture    

Optimizing the compressive strength of concrete containing micro-silica, nano-silica, and polypropylene

Fatemeh ZAHIRI, Hamid ESKANDARI-NADDAF

《结构与土木工程前沿(英文)》 2019年 第13卷 第4期   页码 821-830 doi: 10.1007/s11709-019-0518-6

摘要: Many studies have evaluated the effects of additives such as nano-silica (NS), micro-silica (MS) and polymer fibers on optimizing the mechanical properties of concrete, such as compressive strength. Nowadays, with progress in cement industry provides, it has become possible to produce cement type I with strength classes of 32.5, 42.5, and 52.5 MPa. On the one hand, the microstructure of cement has changed, and modified by NS, MS, and polymers; therefore it is very important to determine the optimal percentage of each additives for those CSCs. In this study, 12 mix designs containing different percentages of MS, NS, and polymer fibers in three cement strength classes(CSCs) (32.5, 42.5, and 52.5 MPa) were designed and constructed based on the mixture method. Results indicated the sensitivity of each CSCs can be different on the NS or MS in compressive strength of concrete. Consequently, strength classes have a significant effect on the amount of MS and NS in mix design of concrete. While, polymer fibers don’t have significant effect in compressive strength considering CSCs.

关键词: mixture method     compressive strength     nano-silica     micro-silica     polypropylene fibers    

Synthesis, insecticidal activities and DFT study of pyrimidin-4-amine derivatives containing the 1,2,4

《化学科学与工程前沿(英文)》 2022年 第16卷 第7期   页码 1090-1100 doi: 10.1007/s11705-021-2091-5

摘要: Twenty six novel pyrimidin-4-amine derivatives containing the 1,2,4-oxadiazole motif were synthesized. Their chemical structures were confirmed by 1H nuclear magnetic resonance (NMR), 13C NMR, and high-resolution mass spectrography. The insecticidal activity results indicated that some of them possessed excellent insecticidal activity (100%) against Mythimna separate, especially for compounds 6d, 6f, 6o, 6w, 6y and 6z. These compounds exhibited no activity against the insects Aphis medicagini and Tetranychus cinnabarinus. The structure- insecticidal activity relationships are discussed. Density functional theory analysis can potentially be used to design more active compounds. These results provide useful insecticide design information for further optimization.

关键词: synthesis     pyrimidin-4-amine derivatives     1     2     4-oxadiazole     insecticidal activity     structure-activity relationship    

Activated carbon-hybridized and amine-modified polyacrylonitrile nanofibers toward ultrahigh and recyclable

Fengli Li, Chuang Chen, Yuda Wang, Wenpeng Li, Guoli Zhou, Haoqin Zhang, Jie Zhang, Jingtao Wang

《化学科学与工程前沿(英文)》 2021年 第15卷 第4期   页码 984-997 doi: 10.1007/s11705-020-2000-3

摘要: Nanofibers with high specific surface area and chemical stability have broad prospects in the applications of adsorption. However, the adsorption capacity is limited by the scarcity of adsorption groups and storage space. Herein, the activated carbon-hybridized and amine-modified nanofibers are prepared by integrating activated carbon (AC) and polyacrylonitrile (PAN) via electrospinning method and the subsequent amination, which could provide additional storage space and adsorption groups for ultrahigh adsorption capability. Thus, the obtained amine-rich porous PAN nanofibers (APAN/AC) readily realized the ultrahigh adsorption capacity for metal ions and dyes in wastewater. Specifically, the adsorption capacity of APAN/AC nanofibers were 284 mg·g for Cr(VI) and 248 mg·g for methyl orange, which were almost 2 and 4 times than that of amine-modified nanofibers (APAN) and carbon-hybridized nanofibers (PAN/AC), respectively. Moreover, the AC inhibited the chain mobility of polymer matrix and thereby endowing APAN/AC nanofibers with excellent recyclability. The adsorption capability retained 80% after nine adsorption-desorption cycles. The adsorption kinetics and corresponding mechanism were further explored. This strategy combines the advantages of polymer nanofibers and AC, opening a new avenue for developing next-generation absorbent materials.

关键词: carbon-hybridized and amine-modified nanofibers     polyacrylonitrile     metal ions and dyes     wastewater     adsorption kinetics    

Dispersion of “guava-like” silica/polyacrylate nanocomposite particles in polyacrylate matrix

QI Dongming, YANG Lei, WU Minghua, SHAO Jianzhong, BAO Yongzhong

《化学科学与工程前沿(英文)》 2008年 第2卷 第2期   页码 127-134 doi: 10.1007/s11705-008-0033-0

摘要: A series of “guava-like” silica/polyacrylate nanocomposite particles with close silica content and different grafting degrees were prepared via mini-emulsion polymerization using 3-(trimethoxysilyl)propyl methacrylate (TSPM) modified silica/acrylate dispersion. The silica/polyacrylate composite particles were melt-mixed with unfilled polyacrylate (PA) resin to prepare corresponding silica/polyacrylate molded composites and the dispersion mechanism of these silica particles from the “guava-like” composite particles into polyacrylate matrix was studied. It was calculated that about 110 silica particles were accumulated in the bulk of every silica/polyacrylate composite latex particle. Both the solubility tests of silica/polyacrylate composite latex particles in tetrahydrofuran (THF) and the section transmission electron microscope (TEM) micrographs of silica/polyacrylate molded composites indicated that the grafting degree of silica particles played a crucial role in the dispersion of silica/polyacrylate composite particles into the polyacrylate matrix. When the grafting degree of polyacrylate onto silica was in a moderate range (ca. 20%–70%), almost all of silica particles in these “guava-like” composite particles were dispersed into the polyacrylate matrix in a primary-particle-level. However, at a lower grafting degree, massive silica aggregations were found in molded composites because of the lack of steric protection. At a greater grafting degree (i.e., 200%), a cross-linked network was formed in the silica/polyacrylate composite particles, which prevented the dispersion of composite particles in THF and polyacrylate matrix as primary particles.

关键词: silica/polyacrylate composite     cross-linked network     –70     guava-like     TEM    

Reaction mechanism of arsenic capture by a calcium-based sorbent during the combustion of arsenic-contaminated

Mei Lei, Ziping Dong, Ying Jiang, Philip Longhurst, Xiaoming Wan, Guangdong Zhou

《环境科学与工程前沿(英文)》 2019年 第13卷 第2期 doi: 10.1007/s11783-019-1110-y

摘要:

Pilot-scale combustion is required to treat arsenic-enriched biomass in China.

CaO addition to arsenic-enriched biomass reduces arsenic emission.

CaO captures arsenic via chemical adsorption to form Ca3(AsO4)2.

关键词: Arsenic contamination     Phytoremediation     Emission control     Calcium-based sorbent     Biomass disposal     Pilot-scale combustion    

Synthesis of spherical parallel manipulator for dexterous medical task

Abdelbadia CHAKER, Abdelfattah MLIKA, Med Amine LARIBI, Lotfi ROMDHANE, Sa?d ZEGHLOUL

《机械工程前沿(英文)》 2012年 第7卷 第2期   页码 150-162 doi: 10.1007/s11465-012-0325-4

摘要:

This paper deals with the design and the analysis of a spherical parallel manipulator (SPM) for a haptic minimally invasive surgery application. First the medical task was characterized with the help of a surgeon who performed a suture technique called anastomosis. A Vicon system was used to capture the motion of the surgeon, which yielded the volume swept by the tool during the anastomosis operation. The identified workspace can be represented by a cone with a half vertex angle of 26°. A multi objective optimization procedure based on genetic algorithms was then carried out to find the optimal SPM. Two criteria were considered, i.e., task workspace and mechanism dexterity. The optimized SPM was then analyzed to determine the error on the orientation of the end effector as a function of the manufacturing errors of the different links of the mechanism.

关键词: spherical parallel manipulator (SPM)     anastomosis     haptic     motion capture     optimization     workspace     dexterity     genetic algorithm     manufacturing errors    

Enhanced activation of persulfate using mesoporous silica spheres augmented Cu–Al bimetallic oxide particles

《化学科学与工程前沿(英文)》 2023年 第17卷 第10期   页码 1581-1592 doi: 10.1007/s11705-023-2327-7

摘要: Herein, Cu–Al bimetallic oxide was synthesized and mixed with mesoporous silica spheres via a simple hydrothermal method. The prepared sample was then analyzed and employed to activate potassium peroxydisulfate for bisphenol A removal. Based on the results of X-ray diffraction, scanning electron microscopy, and energy dispersion spectroscopy, Cu–Al bimetallic oxide was determined as CuO-Al2O3, and mesoporous silica spheres were found around the these particles. At 30 min, a bisphenol A degradation level of 90% was achieved, and it remained at over 60% after five consecutive cycles, indicating the catalyst’s superior capacity and stability. In terms of removal performance, the radical pathway (including SO4•‒, OH •, and O2•‒) and singlet oxygen (1O2) played minor roles, while electron migration between bisphenol A, potassium peroxydisulfate, and the catalyst played a dominant role. The introduction of Al2O3 promoted the formation of surface oxygen vacancies, which improved ligand complex formation between potassium peroxydisulfate and the catalyst, thereby facilitating electron migration. Furthermore, mesoporous silica spheres augment not only enhanced bisphenol A adsorption but also alleviated Cu leaching. Overall, this work is expected to provide significant support for the rational development of catalysts with high catalytic activity for persulfate activation via surface electron migration.

关键词: Cu–Al bimetallic oxides     mesoporous silica spheres     peroxydisulfate     bisphenol A    

A thermodynamic study of the removal of HCl and H

Joseph LEE, Bo FENG

《化学科学与工程前沿(英文)》 2012年 第6卷 第1期   页码 67-83 doi: 10.1007/s11705-011-1162-4

摘要: Advanced integrated-gasification combined-cycle (IGCC) and integrated-gasification fuel cell (IFGC) systems require high-temperature sorbents that are capable of removing hydrogen chloride and hydrogen sulfide from coal derived gases to very low levels. HCl and H S are highly reactive, corrosive, and toxic gases that must be removed to meet stringent environmental regulations, to protect power generation equipment and to control the emissions of contaminants. The thermodynamic behavior of 13 sorbents for the removal of HCl and H S under various conditions including: initial toxic gas concentration (1–10000 ppm), operating pressure (0.1–11 Mpa), temperature (300 K–1500 K), and the presence of H O were investigated. The correlation between HCl and H S was also examined. Thermodynamic calculations were carried out for the reactions of the 13 sorbents using a FactSage 5.2 software package based on free energy minimization. The sorbents, Na CO , NaHCO , K CO , and CaO are capable of completely removing chlorine at high temperatures (up to ~1240 K) and at high pressures. Water vapor did not have any significant effects on the dechlorination capability of the sorbents. Nine of the sorbents namely; Cu O, Na CO , NaHCO , K CO , CaO, ZnO, MnO, FeO, and PbO, were determined to have great potential as desulfurization sorbents. Cu O and ZnO had the best performance in terms of the optimum operating temperature. The addition of water vapor to the reactant gas produces a slightly detrimental effect on most of the sorbents, but FeO exhibited the worst performance with a reduction in the maximum operating temperature of about 428 K. The dechlorination performance of the alkali sorbents was not affected by the presence of H S in the reactions. However, the desulfurization capability of some sorbents was greatly affected by the presence of HCl. Particularly, the performance of Cu O was significantly reduced when HCl was present, but the performance of FeO improved remarkably. The thermodynamic results gathered are valuable for the developments of better sorbents.

关键词: syngas cleaning     sorbent     desulfurization     dechlorination    

The modification of titanium in mesoporous silica for Co-based Fischer–Tropsch catalysts

《化学科学与工程前沿(英文)》 2022年 第16卷 第8期   页码 1224-1236 doi: 10.1007/s11705-022-2139-1

摘要: Ordered SBA-15 mesoporous silica with incorporated titanium was successfully synthesized via a one-pot hydrothermal crystallization method. The characterization including powder X-ray diffraction, Brunauer–Emmett–Teller, transmission electron microscope, temperature-programmed reduction, temperature-programmed desorption, Fourier transform infrared and ultraviolet-visible-near infrared spectrometer was performed to explore the physical and chemical structures of both the supports and the catalysts. The results showed that titanium was successfully incorporated into the mesoporous silica framework with a limited amount of titanium (Si/Ti > 20), and the mesoporous structure was retained. However, the increased titanium content inevitably resulted in the formation of anatase TiO 2 particles on the support surface. The increased incorporated titanium strengthened the interactions between cobalt species and supports, which was favorable for the cobalt species dispersion, despite the limited cobalt oxide reducibility. The enhanced metal-support interactions were beneficial for the CO/H2 ratio at the active cobalt sites, which facilitated the formation of more C5+ hydrocarbons. This study provides a promising method for support modification with incorporated-heteroatoms for the rational development of Fischer–Tropsch catalysts.

关键词: Fischer–Tropsch synthesis     titanium incorporation     mesoporous silica     metal-support interactions     C5+ selectivity    

标题 作者 时间 类型 操作

New nanostructured sorbents for desulfurization of natural gas

Lifeng WANG, Ralph T. YANG

期刊论文

Reaction and characterization of crosslinking hyperbranched poly (amine-ester) with succine anhydride

XIAO Ling, WEI Xiuzhen, ZHU Baoku

期刊论文

Preparation and selection of Fe-Cu sorbent for COS removal in syngas

Bowu CHENG, Zhaofei CAO, Yong BAI, Dexiang ZHANG

期刊论文

Activated carbons and amine-modified materials for carbon dioxide capture –– a review

Zhenhe CHEN, Shubo DENG, Haoran WEI, Bin WANG, Jun HUANG, Gang YU

期刊论文

Desulfurization performance of iron-manganese-based sorbent for hot coal gas

Xiurong REN, Weiren BAO, Fan LI, Liping CHANG, Kechang XIE

期刊论文

Efficient MgO-doped CaO sorbent pellets for high temperature CO

Zhihong Xu, Tao Jiang, Hao Zhang, Yujun Zhao, Xinbin Ma, Shengping Wang

期刊论文

Optimizing the compressive strength of concrete containing micro-silica, nano-silica, and polypropylene

Fatemeh ZAHIRI, Hamid ESKANDARI-NADDAF

期刊论文

Synthesis, insecticidal activities and DFT study of pyrimidin-4-amine derivatives containing the 1,2,4

期刊论文

Activated carbon-hybridized and amine-modified polyacrylonitrile nanofibers toward ultrahigh and recyclable

Fengli Li, Chuang Chen, Yuda Wang, Wenpeng Li, Guoli Zhou, Haoqin Zhang, Jie Zhang, Jingtao Wang

期刊论文

Dispersion of “guava-like” silica/polyacrylate nanocomposite particles in polyacrylate matrix

QI Dongming, YANG Lei, WU Minghua, SHAO Jianzhong, BAO Yongzhong

期刊论文

Reaction mechanism of arsenic capture by a calcium-based sorbent during the combustion of arsenic-contaminated

Mei Lei, Ziping Dong, Ying Jiang, Philip Longhurst, Xiaoming Wan, Guangdong Zhou

期刊论文

Synthesis of spherical parallel manipulator for dexterous medical task

Abdelbadia CHAKER, Abdelfattah MLIKA, Med Amine LARIBI, Lotfi ROMDHANE, Sa?d ZEGHLOUL

期刊论文

Enhanced activation of persulfate using mesoporous silica spheres augmented Cu–Al bimetallic oxide particles

期刊论文

A thermodynamic study of the removal of HCl and H

Joseph LEE, Bo FENG

期刊论文

The modification of titanium in mesoporous silica for Co-based Fischer–Tropsch catalysts

期刊论文