查找使用阿拉丁产品的科研文献

Synthesis, Characterization and Application of Amine-Functionalized Hierarchically Micro-Mesoporous Silicon Composites for CO2 Capture in Flue Gas

Yilan Chen,Junjie Wu,Xin Wang,Minyi Liu,Yamin Liu

An efficient CO2adsorbent with a hierarchically micro-mesoporous structure and a large number of amine groups was fabricated by a two-step synthesis technique. Its structural properties, surface groups, thermal stability and CO2adsorption performance were fully investigated. The analysis results show that the prepared CO2adsorbent has a specific hierarchically micro-mesoporous structure and highly uniformly dispersed amine groups that are favorable for the adsorption of CO2. At the same time, the CO2adsorption capacity of the prepared adsorbent can reach a maximum of 3.32 mmol-CO2/g-adsorbent in the actual flue gas temperature range of 303–343 K. In addition, the kinetic analysis results indicate that both the adsorption process and the desorption process have rapid adsorption/desorption rates. Finally, the fitting of the CO2adsorption/desorption experimental data by Avrami’s fractional kinetic model shows that the CO2adsorption rate is mainly controlled by the intra-particle diffusion rate, and the temperature has little effect on the adsorption rate.Keywords:CO2adsorbent;hierarchically micro-mesoporous silicon;amine-functionalized;kinetic

Control the greenhouse gas emission via mediating the dissimilatory iron reduction: Fulvic acid inhibit secondary mineralization of ferrihydrite

Mingwei Wang,Zhiqiang Zhao,Yang Li,Song Liang,Yutong Meng,Tengfei Ren,Xiaoyuan Zhang,Yaobin Zhang

Reducing methane emission is of great importance to control the global greenhouse effect. Dissimilatory iron reduction (DIR) coupling of organic matter decomposition may suppress methane production via reducing primary electron donors available for methanogenesis. However, during DIR, the amorphous iron oxides (e.g., ferrihydrite) are easy to transform into more stable crystalline iron minerals, which slowdowns the rate of DIR. Humic substance (HS) with redox activity has been extensively reported to facilitate DIR via “electron shuttles” mechanism, yet little known about the effect of HS on mediating the mineralization of iron oxides and the subsequent influences on DIR and methanogenesis. To clarify this, ferrihydrite and fulvic acid (FA) (as the model substance of HS) were supplied to anaerobic methanogenesis systems. Results showed that FA could significantly decrease the formation of crystalline iron oxides, enhance DIR rate by 13.72% and suppress methanogenesis by 25.13% compared to ferrihydrite supplemented only. By X-ray absorption spectra analysis, it was found that FA could complex with ferrihydrite via forming a Fe-C/O structure on the second shell of Fe atom. Quantum chemical calculation further confirmed that FA reduced the adsorption energy between Fe(II) and ferrihydrite. Our study suggested that rational use of HS to mediate mineralization pathway of iron oxides could efficiently improve the availability of iron oxides to drive DIR and control the conversion of organics into CH 4 in natural or engineered systems.

Fabrication of polyarylate thin-film nanocomposite membrane based on graphene quantum dots interlayer for enhanced gas separation performance

Yuhui Niu,Yuhao Chen,Shanshan Bao,Haixiang Sun,Yaxuan Wang,Baosheng Ge,Peng Li,Yingfei Hou

Interlayered-thin film nanocomposite (i-TFN) membranes with nanomaterials as the interlayer has attracted more and more attention of researchers in recent years due to the effective regulation of the separation layer structure in the membrane separation field. In this work, the amino-functionalized graphene quantum dots (N-GQDs) were synthesized and applied as an interlayer to modify the polyethersulfone (PES) ultrafiltration substrate. Then interfacial polymerization (IP) between trimesoyl chloride (TMC) and β-cyclodextrin (β-CD) was performed to prepare novel i-TFN polyarylate membranes for CO 2 /N 2 separation. The effect of the N-GQDs deposition amount on the structure and gas separation performance of the composite membrane was studied thoroughly. The results indicated that the i-TFN polyarylate membrane presented a particular sandwich structure and provided an effective transport channel for the diffusion of CO 2 . Moreover, the affinity of the N-containing groups (e. g. amino and amide groups) in the i-TFN membrane and the CO 2 molecules helped to increase the CO 2 /N 2 separation selectivity. At the optimal preparation condition, the obtained i-TFN membrane showed CO 2 /N 2 selectivity of 23.3 with CO 2 permeance of 174.5 GPU. This work proposes a novel nanomaterial interlayer to effectively improve the gas permselectivity by regulating the structure of i-TFN membranes, which has significant instruction for the preparation of high-performance i-TFN by exploring the interlayer of other nanomaterials.

Metal Modified NaY Zeolite as Sorbent for the Ultra-Deep Removal of Thiophene in Simulated Coke Oven Gas

Fanjing Wei,Xiaoqin Guo,Weiren Bao,Liping Chang,Junjie Liao

The ultra-deep removal of thiophene is essential for the conversion of coke oven gas to methane and metal modified Y zeolite has excellent thiophene adsorption capacity. The effects of temperature on chemisorption between metal modified Y zeolite and thiophene and the reductive gases in coke oven gas on the thiophene adsorption performance still remains ambiguous. To address the aforementioned aims, series of NaMY (M = Ce, Ni, Zn and Ag) were prepared via ion-exchanged with Na+of NaY, and two comparable sets of thiophene adsorption evaluation were conducted in a fixed bed reactor: (1) NaY and NaMY were evaluated at different temperatures in simulated coke oven gas, and (2) NaCeY was evaluated in N2and different reductive atmospheres. The results show that NaNiY, NaZnY and NaAgY could adsorb thiophene via π-complexation, however, NaCeY mainly through S-Ce bond. Π complexation becomes weak above 150 °C, and the strength of S-Ce bond varies little when the temperature rises to 250 °C. Compared with that of other sorbents, the breakthrough adsorption capacity for thiophene (Qb-thiophene) of NaAgY reaches the highest 144 mg/g at 100 °C, but decreases sharply when temperature rises to 200 °C. NaCeY has relatively low variation inQb-thiophenefrom 100 °C to 200 °C. Moreover, Ce(IV) in NaCeY is more favorable for thiophene adsorption than Ce(III) in coke oven gas and the presence of H2and CO would reduce the desulfurization activity of NaCeY. For the industrial utilization of thiophene ultra-deep removal, NaAgY has an excellent potential below 150 °C, while NaCeY with more Ce(IV) has a good prospect at 150–250 °C.Keywords:coke oven gas;thiophene;adsorption;Y zeolite;metal modification

Ultra-efficient trimethylamine gas sensor based on Au nanoparticles sensitized WO3 nanosheets for rapid assessment of seafood freshness

Cheng Zhao,Jiabin Shen,Shanshan Xu,Jing Wei,Haiquan Liu,Siqi Xie,Yingjie Pan,Yong Zhao,Yongheng Zhu

Trimethylamine (TMA) is an organic amine gas used as an important index to assess the seafood freshness. In this work, an ultra-efficient trimethylamine gas sensor was constructed by ultrasonic treatment loading of Au nanoparticles (∼4 nm) on WO 3 nanosheets prepared by solvothermal self-assembly method. The response of the sensor to 25 ppm TMA was as high as 217.72 (R air /R gas ) at 300 ℃. In addition, the Au/WO 3 nanosheets sensor exhibited rapid response-recovery time (8 s/6 s), low detection limit (0.5 ppm), and high selective detection of TMA. Moreover, the composition of volatiles produced by decay of Larimichthys crocea (0–15 days) was examined, which proved that the detection of TMA by the Au/WO 3 sensor can evaluate the freshness of Larimichthys crocea . Such a magnificent gas sensing performance reveals that the Au/WO 3 sensor has remarkable application potential in rapid and non-destructive seafood freshness assessment on the spot.

Microtubular Fe/Mn-promoted CaO-Ca12Al14O33 bi-functional material for H2 production from sorption enhanced water gas shift

Chunxiao Zhang,Yingjie Li,Zirui He,Jianli Zhao,Dong Wang

Herein, a hollow microtubular Fe/Mn-promoted CaO-Ca 12 Al 14 O 33 bi-functional material was prepared by the bio-template method and used for H 2 production from sorption enhanced water gas shift (SEWGS). The microtubular Fe/Mn-promoted CaO-Ca 12 Al 14 O 33 exhibits excellent CO 2 capture and H 2 production performance in SEWGS/regeneration cycles. The stable hollow microtubular structure improves available adsorption and catalytic sites in Fe/Mn-promoted CaO-Ca 12 Al 14 O 33 for CO 2 capture and H 2 production. Mn addition improves CO 2 affinity capacity of the microtubular material. The Fe-Mn interaction increases redox ability of Fe 3+ /Fe 3+, 2+ , which promotes CO conversion. Moreover, the formed Ca 2 Fe 2 O 5 and Ca 2 MnO 4 both increase oxygen vacancies to promote catalytic activity of the microtubular material for WGS and its CO 2 capture capacity. The CO conversions for the microtubular material with the Fe/Mn/Al/Ca molar ratio= 10/2/10/100 are 98.7% and 94.0% after 20 cycles under the mild and severe calcination conditions, respectively. The hollow microtubular bi-functional material shows good prospect for efficient H 2 production from SEWGS.

Deep-basin gas generation via organic–inorganic interactions: New insights from redox-controlled hydrothermal experiments at elevated temperature

Yanan Yang,Ningning Zhong,Jia Wu,Yueyang Pan

Under hot, deep-basin conditions, hydrogen-to-carbon ratios of residual kerogen are low. Whether ubiquitous water in sedimentary environments contributes hydrogen directly to hydrocarbon gas formation through organic-inorganic interactions is, therefore, critical for natural gas generation. Accordingly, we conducted laboratory experiments on immature to overmature kerogens at 300–600°C and 700 bar to examine the chemical interactions between kerogens and fluid under varying redox states and hydrothermal conditions. Mineral buffers, comprised of magnetite-hematite, nickel‑nickel oxide, cobalt‑cobalt oxide, and molybdenum‑molybdenum trioxide, were added to the experiments to control the redox state of the fluid from geologically reasonable to generally excessive values. The kerogens and mineral buffers were spatially isolated using double-capsule techniques to prevent contact catalysis. Our results indicated that chemical interactions between kerogens and water depended strongly on the kerogen thermal maturity and fluid redox state. The chemical interactions of overmature kerogens with reducing water were stronger than those of immature kerogens, which could be ascribed to the weaker competitive transfer of hydrogen from organics to organics than from water to organics. Unexpectedly high amounts of hydrocarbon gas were generated by incorporating water-derived hydrogen in the pyrolysis of overmature kerogens, and the yields increased under low to high reducing fluid conditions for a given temperature. Along with the increasing thermal maturity, residual kerogen eventually became ineffective for hydrocarbon gas generation through reduction reactions. Demethylation, bridge bond cleavage reaction, aromatic structure ring opening reactions in residual kerogen and subsequent redox reaction of intermediate products with reducing fluids is evidenced as the possible reaction mechanisms. The produced hydrocarbon gas under f H 2 level of oilfield water is characterized by high dryness (99 mol%) and more-enriched 13 C in CH 4 compared with precursors. Natural gas deep within the Sichuan and Appalachian basins with similar characteristics suggests that our simulated organic–inorganic interactions could occur widely under natural conditions. Consequently, a potentially prolific source of natural gas may be formed by the overmature source rocks in the deep basin and fluid redox should be considered for gas potential evaluation of overmature source rocks.

Simultaneous detection of multiple phenolic compounds in fish by gas chromatography-mass spectrometry following a modified QuEChERS cleanup

Jiali Xing,Yang Li,Ruihang Zheng,Hao Shen,Xiaorong Xu,Lingyan Mao,Xiaohu Luo,Jian Shen,Weirong Yao

Promotion effects of oxygen vacancies on activity of Na-doped CeO2 catalysts for reverse water gas shift reaction

Bowen Lu,Tai Zhang,Liqi Zhang,Yongqing Xu,Zewu Zhang,Fan Wu,Xiaoshan Li,Cong Luo

CeO 2 -based catalysts have been widely used in the CO 2 hydrogenation process. The oxygen vacancies on CeO 2 resulted from Na ion incorporation play a vital role in CO 2 conversion activity, the effect of Na + ion-doped in CeO 2 during CO 2 hydrogenation was rarely studied. In this work, the LN-CeO 2 catalysts with different n NaOH :n Ce ratios were prepared with liquid nitrogen(Liquid Nitrogen-CeO 2 , LN-CeO 2 ), and the effect of the n NaOH :n Ce ratio on the microstructure of the LN-CeO 2 catalysts were evaluated. The best CO 2 hydrogenation performance was achieved by LN-CeO 2 -100 with a CO production rate of 3.90 mol/g cat· h at 800 °C (100% CO selectivity). The kinetic results indicated that the CO 2 hydrogenation performance difference among these LN-CeO 2 catalysts resulted from the CO 2 activation process. Oxygen vacancies could enhance CO 2 activation on the surface of LN-CeO 2 , and oxygen vacancies displayed a linear correlation relationship with the Na content doped in LN-CeO 2 . The highest concentration of oxygen vacancies resulted from Na ion incorporated and lower CO 2 reaction order was closely related to CO 2 hydrogenation performance of LN-CeO 2 -100. These results will give insight into the Na effect on the CO 2 hydrogenation mechanism over CeO 2 .

One-pot cogeneration of phenol-rich bio-oil, hydrogen-rich gas and solid carbon degradation material from reed

Jian Hu,Long Chen,Pengzhang Chen,Shixi Gu,Yu Zhou,Jilong Zhang,Wenjie Zhao,Honglin Tao,Nan Zhou,Baobin Mi,Fangfang Wu

A newly developed two-step catalytic pyrolysis process (TSCP) based on poly-generation technology is proposed to convert reed straw (RS) into phenol-rich bio-oil, hydrogen-rich gas, and solid carbon degradation material over iron-loaded activated carbon. The effects of the first step pyrolysis temperature (T1) and catalyst composition on the product distribution and target product selectivity were investigated. When T1 was 350 °C and 10% Fe/AC catalyst was selected, the concentration of phenolic compounds and H 2 peaked at 63.87 area% and 63.29 vol%, respectively. The iron-loaded activated carbon catalysts promoted the decarboxylation and decarbonylation reactions of cellulose and hemicellulose decomposition products, as well as the demethylation and demethoxylation reactions of lignin for the selective production of phenolic compounds and hydrogen gas . In addition, 94.7% quinclorac (10 mg/L) removal was achieved with 0.2 g/L 10% Fe/AC catalyst-doped pyrolysis carbon and 2 mM PMS within 90 min. This study could realize the high-value comprehensive utilization of reed and provide a reference for the full quantitative utilization of other agricultural and forestry wastes.

Hybrid Aerogel Triboelectric Nanogenerator Based on the Synergistic Effect of Solid–Solid/Gas–Solid Triboelectricity and Piezoelectric Polarization

Tianci Huang,Yong Long,Bingqi Zhao,Qilin Hua,Zhong Lin Wang,Weiguo Hu

Aerogels, due to their unique interconnected 3D networks, and large number of air-filled pores, extend the structural characteristics and physicochemical properties of the nanoscale to the macro level. However, aerogels made from a single component can hardly meet the needs of multifunctional energy harvesting/supply situations. Here, a BaTiO3-based hybrid aerogel (BTO HA) with 3D network structure was prepared. When the BTO HA is used as the electrode of triboelectric nanogenerator (BTO HA-TENG), high electrical output performances were obtained, which is due to the synergistic effect of solid–solid contact electrifications between the two electrification layers, the gas–solid contact electrifications between the inner surface of BTO HA and the air filled in the aerogel pores, and the piezoelectricity of the doped BaTiO3 nanoparticles. The BTO HA-TENG exhibited excellent fatigue resistance and structural stability after 12,000 cycles of alternatively contact/separation tests, and it can not only provide stable power supply for commercial capacitors, drive small mobile electronic devices but also can be used as a self-powered sensor to monitor human motion signals. Compared with traditional TENGs depending on surface charge transfer, the BTO HA-TENG exhibited its unique advantage that it can generate and transfer triboelectric charges by 3D volume, which boost TENGs’ electrical output performances.

Facile engineering of metal–organic framework derived SnO2-ZnO composite based gas sensor toward superior acetone sensing performance

Hui Zhang,Shisong Guo,Wenjun Zheng,Haichao Wang,Hua-Yao Li,Mei-Hui Yu,Ze Chang,Xian-He Bu,Huan Liu

Aiming to achieve high-sensitivity disease diagnosis, it is of great significance to continuously improve the sensing performance of metal oxide based sensors. The morphology and component of metal oxides can be rationally engineered by using metal–organic frameworks as highly versatile platforms. Herein, the bimetallic Sn/Zn-ZIF-8 is synthesized by self-assembly, and then SnO 2 -ZnO hollow nanoparticles are obtained by using bimetallic Sn/Zn-ZIF-8 as precursor. The obtained SnO 2 -ZnO composite maintained the dodecahedral structure of Sn/Zn-ZIF-8, and in which SnO 2 is orthogonal due to the framework-induced effect. Based on the unique structure and composition of SnO 2 -ZnO, 6% SnO 2 -ZnO exhibits excellent selectivity, high response, low detection limit (0.82 ppb) and good response linearity between response and concentration of acetone, showing the potential of the practical application in clinical diagnosis of diabetic patients. In-depth discussions reveal that the excellent sensing performance can be attributed to the n-n heterostructure of SnO 2 -ZnO that is favorable for electron transport, the larger adsorption energy to acetone that results from orthogonal SnO 2 , and the abundant active reaction sites provided by the dodecahedral mesoporous structure. This synthetic strategy may provide an effective method for the facile engineering of high-performances metal oxide-based sensors toward practical health assessment.