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This paper reports the discovery of a magnetophotoluminescence response in metallofullerene Y3N@C80 triggered by the triplet excited state. In experiments, Y3N@C80 exhibits magnetic field‐dependent (0→±42 T) phosphorescence emission at 4.2 K. Crucially, with increasing magnetic field, the phosphorescence peaks shift to longer wavelengths owing to the Zeeman effect. Further, a nanoring of [9]CPPH is employed to modulate the magnetophotoluminescence response of Y3N@C80 through host−guest interaction. The circularly polarized phosphorescence spectra of Y3N@C80 and Y3N@C80⊂[9]CPPH are investigated to further reveal their magnetophotoluminescence properties using the technique of field‐induced circular polarization (FICPO). These results show that metallofullerene Y3N@C80 with magnetophotoluminescence response has potential applications in spin‐related optical devices and quantum technology. [ABSTRACT FROM AUTHOR]

Lactic acid is an important organic acid with wide applications, and preparation of lactic acid from biomass-derived 1,2-propanediol was considered a green reaction route. In this paper, a Cu modified Au/γ-Al2O3 catalyst was designed for the oxidative esterification of 1,2-propanediol to methyl lactate in an alkali-free methanol system. The structural properties of the Au–Cu/γ-Al2O3 catalyst were characterized by various characterization methods, and interaction between Au nanoparticles and Cu species was discovered. Moreover, the catalytic tests showed that the Cu modified Au/γ-Al2O3 catalysts exhibited higher methyl lactate selectivity than the monometallic Au/γ-Al2O3 catalyst. It was revealed that the synergistic effect between the Au nanoparticles and Cu species could promote the oxidation of primary hydroxyl groups of 1,2-propanediol to produce methyl lactate and reduce the generation of by-products. In addition, a reasonable reaction pathway for the oxidative esterification of 1,2-propanediol was proposed based on the comparative experiments. These findings may provide favorable guidance for design of Au based nanocatalysts for the oxidative esterification of alcohols to esters and carboxylic acids. [ABSTRACT FROM AUTHOR]

Palladium (Pd) nanostructures are highly active non-platinum anodic electrocatalysts in alkaline direct methanol fuel cells (DMFCs), and their electrocatalytic performance relies highly on their morphology and composition. This study reports the preparation, characterizations, and electrocatalytic properties of palladium-copper alloys loaded on the carbon support. XC-72 was used as a support, and hydrazine hydrate served as a reducing agent. PdxCuy/XC-72 nanoalloy catalysts were prepared in a one-step chemical reduction process with different ratios of Pd and Cu. A range of analytical techniques was used to characterize the microstructure and electronic properties of the catalysts, including transmission electron microscopy (TEM), X-ray diffractometry (XRD), X-ray photoelectron spectroscopy (XPS), and inductively coupled plasma emission spectroscopy (ICP-OES). Benefiting from excellent electronic structure, Pd3Cu2/XC-72 achieves higher mass activity enhancement and improves durability for MOR. Considering the simple synthesis, excellent activity, and long-term stability, PdxCuy/XC-72 anodic electrocatalysts will be highly promising in alkaline DMFCs. [ABSTRACT FROM AUTHOR]

In this paper, we propose a knowledge sharing oriented approach to enable a robot to reuse other robots' knowledge by adapting itself to the inverse dynamics model of the knowledge-sharing robot. The purpose of this work is to remove the heavy fine-tuning procedure required before using a new robot for a task via reusing other robots' knowledge. We use the Neural Knowledge DNA (NK-DNA) to help robots gain empirical knowledge and introduce a Knowledge Adaption Module (KAM) utilizing the deep neural networks (DNN) for knowledge reuse. The initial experiment shows that the target robot can adapt to the inverse dynamic model of the source robot via our KAM and reuse the knowledge shared by the source robot. [ABSTRACT FROM AUTHOR]

Luminescent thermometers provide a non-contact method of probing temperature with high sensitivity and response speed at the nanoscale. Synergistic photoluminescence from different activators can realize high sensitivity for luminescent thermometers by finely selecting ions with specific crystallographic sites. Herein, the more temperature-sensitive Mn4+ and the less-sensitive Eu3+ (or Sm3+) activators are co-doped into a Ca2GdSbO6 matrix to form an effective thermometer, where Mn4+ and Eu3+ (or Sm3+) ions occupy the Sb5+ and Gd3+ sites, respectively. The co-doping of Eu3+ ions or Sm3+ ions leads to lattice expansion of Ca2GdSbO6 matrix and a tuned narrow emission from deep-red to orangish-red. According to the ratio of luminescence intensity, the maximal Sa and Sr values are 0.19 K−0 (347 K) and 1.38% K−( (420 K) for Ca2GdSbO6:Mn4+/Eu3+ probe and 0.26 K−p (363 K) and 1.55% K−( (430 K) for Ca2GdSbO6:Mn4+/Sm3+ probe thermometers, respectively. In addition, thermometers based on Mn4+ emission lifetimes can provide the highest relative sensitivity of 1.47% K−s at 425 K. Thus, the highly-temperature-sensitive Ca2GdSbO6:Mn4+/(Eu3+ or Sm3+) phosphor is a promising candidate for practical luminescence thermometers. [ABSTRACT FROM AUTHOR]

HZSM-5@silicalite-1 catalysts were prepared by the hydrothermal method, and the structure, morphology, acidity and pore texture of core–shell catalysts were studied by XRD, SEM, TEM, NH3-TPD, Py-IR and N2 adsorption/desorption isotherms in detail. Their catalytic performances were tested in the alkylation reaction of toluene with methanol. The results showed that a coating layer was formed in the form of silicalite-1 on HZSM-5. NH3-TPD measurements indicated that HZSM-5@silicalite-1 contained less strong acid sites but more weak acid sites than the parent HZSM-5. The selectivity of p-xylene for toluene alkylation was approximately linear with the percentage of weak acid in total acid. Under the optimal reaction conditions, the conversion of toluene was 34.15%, and the selectivity of p-xylene was 96.77%. [ABSTRACT FROM AUTHOR]

Luminescence thermometry has been widely concerned by researchers due to its quick response, high spatial resolution, and remote measurement. However, low sensitivity is still an existing problem and affects its development. Herein, the luminescence thermometer with high sensitivity taking advantage of the distinguished thermal response between Eu3+ and Mn4+ is designed. Excitedly, Eu3+ exhibits an anti-thermal quenching behavior under 310 nm excitation and a slight thermal quenching behavior under 393 nm excitation due to the energy transfer of host→Eu3+, while Mn4+ presents a strong thermal quenching behavior. Moreover, the energy transfer of Eu3+→Mn4+ (λ ex = 310 nm and λ ex = 393 nm) can also be observed for the Ca 2 Sb 2 O 7 : Eu3+, Mn4+ phosphors during the heating process. On the basis of the diverse thermal quenching behavior of Eu3+ and Mn4+, the thermometric performances are investigated by utilizing the fluorescence intensity ratio (FIR) of Eu3+(5D 0 →7F 2)/Mn4+(2E g →4A 2g) under a dual-wavelength excitation. The maximum relative sensitivities of the designed phosphors are determined to be 4.072% K−1 at 305 K under 310 nm and 3.072% K−1 at 351 K under 393 nm excitation. It's worth noting that the thermometric characteristic can be modified by various excitation wavelengths. Hence, the developed Ca 2 Sb 2 O 7 : Eu3+, Mn4+ phosphors have great potential in the field of luminescence thermometry and provide an effective strategy for designing high-sensitivity dual-wavelength excitation optical thermometers. [Display omitted] [ABSTRACT FROM AUTHOR]

[Display omitted] • A novel Mn4+-doped BaLaCa 1−x Mg x SbO 6 red phosphor with tunable and enhanced luminescence characteristics has been investigated. • The luminescence lifetime thermometry has been achieved. • The thermometric performance can be regulated by modulating the Ca/Mg ratio. • A new strategy to significantly improve the sensitivity of luminescence lifetime thermometers. Mn4+-activated phosphors are of great interest in luminescence lifetime thermometry due to the luxuriant luminescence properties influenced by the locally surrounding crystal field. It is highly desirable to develop effective Mn4+-based luminescence lifetime thermometry through modulating the structural parameters. In this work, by introducing the smaller Mg2+ ions to replace Ca2+ site in the BaLaCaSbO 6 matrix, a 4.2-fold enhance in the luminescence intensity, red-shifted from 690 nm to 698 nm, as well as luminescence lifetime increase from 0.212 to 0.951 ms is achieved. These modulations are mainly attributed to the strengthen pressure on the local structure, superior lattice rigidity and suppresses non-radiative transition after the substitution of smaller Mg2+. Interestingly, owing to the obvious thermal quenching behavior of Mn4+ ions in the matrix, effective lifetime-based luminescence thermometry can be realized. Mg2+ dopant results in the improvement of the absolute sensitivity from 1.22 µsK−1 (BaLaCaSbO 6 :Mn4+@408 K) to 4.88 µsK−1 (BaLaCa 0.1 Mg 0.9 SbO 6 :Mn4+@401 K). [ABSTRACT FROM AUTHOR]

(3 R,4 R)-4-Acetoxy-3-[( R)-1(( t-butyldimethylsilyl)oxy)-ethyl]-1-methoxyphenyl-2-azetidinone (an important precursor for the synthesis of carbapenem antibiotics) was synthesized under mild and green conditions catalyzed by Cu-OMS-2. Normal to excellent isolated yields were obtained under given conditions. [ABSTRACT FROM AUTHOR]

Abstract: A series of ruthenium catalysts supported by H–Y, Na–Y and TiO2 were fabricated and characterized by XRD, BET and IR of adsorbed pyridine to establish some physicochemical properties of the catalysts. The activity of the catalysts was tested in hydroquinone hydrogenation reaction and the yield of 1, 4-cyclohexanediol was found to be in the following increasing order: Ru/TiO2 << Ru/H–Y < Ru/Na–Y. IR of adsorbed pyridine analysis revealed that Ru/Na–Y catalyst possessed optimal ratios of Lewis to Brønsted acid which could contribute to high selectivity of Ru/Na–Y catalyst for hydrogenation of hydroquinone. [Copyright &y& Elsevier]

Vehicle derailment is difficult to explore because accidents are caused by many factors. In this paper, derailment behaviors are divided into three categories: friction-type derailment, structure-type derailment, and nonlinear-type derailment. Each category has unique characteristics. Wheel climb is a frequent form of friction-type derailment, resulting from mechanical and generally dynamical behavior between wheel and rail. Dynamic simulation is an important tool for prediction of friction-type derailment. There exists a critical point during wheel climb, and lateral normal force primarily prevents the wheel's moving up. Structure-type derailment is a result of component failure, appearing as local, then developing into general derailment. Factors affecting the development process, such as failure modes, front wheelset derailment, and vehicle speed, are discussed. Nonlinear-type derailment commonly occurs as impact derailment when the vehicle loses stability beyond a nonlinear critical speed. The critical speed for derailment is derived, and the case of a bifurcation diagram is studied. Although nonlinear-type derailment is sensitive to initial conditions, the possibility of accurate prediction is discussed. [ABSTRACT FROM AUTHOR]

Abstract: Polyoxometalates (abbreviated as POMs) are useful acids and oxidation catalysts in various reactions since its catalytic features can be controlled at a molecular level. This review summarizes some recent research progress in catalytic application of Keggin and Wells–Dawson type polyoxometalates. Particular attention is given to most developments of our recent studies on the use of POMs as heterogeneous and homogeneous catalysts for the selective oxidation and acid-catalyzed reactions. [Copyright &y& Elsevier]

Abstract: Wells–Dawson type Heteropolyacids (H6+n P2Mo18−n V n O62) (n =0–2, 4) have proved to be efficient heterogeneous catalysts for the reaction of epoxides with carbonyl compounds to form 1,3-dioxolane derivatives. Especially, when H7P2Mo17VO62 was used to catalyze the reaction between acetone and epoxypropane, the selectivity to 1,3-dioxolane reached to 93.3% with nearly complete conversion of epoxide and 1.1×104 h−1 of TOF. [Copyright &y& Elsevier]

Based on the space engagement theory, a special type of noninvolute beveloid gears meshing with line contact between intersecting axes has been studied in this paper for the first time. The engagement equation and tooth profile equation have been presented by applying the theory of gearing. Meanwhile the tooth profile errors and axial errors have been calculated by means of numerical analysis in this paper. As a numerical example, the three-dimensional simulation of beveloid gears between intersecting axes has been finished by means of the CAD system, Pro/Engineer. [Copyright &y& Elsevier]

HZSM-5 is a widely used catalyst for the conversion of methanol to aromatics (MTA), but its single micropore system often results in severe diffusion limitations, leading to the decrease of reaction rate and the change of selectivity to aromatics, as well as affecting the carbon deposition and catalyst deactivation. Thus, an ingenious protective desiliconization method with a mixed solution of sodium hydroxide and tetrapropylammonium hydroxide as a desiliconization agent was developed to create hierarchical porous systems without destruction of the main structure of the molecular sieve. Such modification leads to the greatly increased mesoporous volume from 0.12 to 0.38 cm3 g−1, and only slightly decreased microporous volume from 0.12 to 0.09 cm3 g−1. However, the desiliconization sharply increases the acidity of the catalyst (from 0.248 to 0.341 mmol g−1 for the strong acid sites), which may significantly affect the distribution of aromatics and accelerate the carbon deposition rate. Thus, the deposition of inert SiO 2 on the catalyst surface is subsequently carried out to passivate the surface acidity and adjust the orifice of the catalyst. Accordingly, a hierarchical porous HZSM-5 molecular sieve catalyst (Si@Z5-Na + TP) with suitable acidity is precisely prepared, which exhibits the high selectivity to benzene, toluene and xylenes (BTX) with the excellent anticoking ability in the MTA reaction. The selectivity to BTX in aromatics (63.32%) and the carbon deposition rate (0.91 mg g cat −1 h−1) over the Si@Z5-Na + TP catalyst are both much more superior than those over the parent HZSM-5 catalyst (47.5% and 2.23 mg g cat −1 h−1, respectively). A composite catalyst Si@Z5-Na + TP amalgamating with hierarchical porous system and suitable acidity was successfully fabricated by protective desiliconization and subsequent silanization modification, which exhibited high selectivity for benzene, toluene and xylenes (BTX) and excellent anticoking ability in the transformation reaction of methanol to aromatics (MTA). Image 1 • The hierarchical porous HZSM-5 with suitable acid content is designed precisely. • The mixed solution of NaOH and TPAOH was used as protective desiliconization agent. • The deposition of inert SiO 2 is then done to modify the surface acid density. • The designed catalyst exhibits high selectivity for BTX in the MTA reaction. • The catalyst also exhibits excellent anticoking ability in the MTA reaction. [ABSTRACT FROM AUTHOR]

Cyclohexane epoxide, which contains highly active epoxy groups, plays a crucial role as an intermediate in the preparation of fine chemicals. However, controlling the epoxidation pathway of cyclohexene is challenging due to issues such as the allylic oxidation of cyclohexene and the ring opening of cyclohexane epoxide during the cyclohexene epoxidation process to form cyclohexane oxide. This review focuses on the structure‐activity relationships and synthesis processes of various heterogeneous transition metal‐based catalysts used in cyclohexene epoxidation reactions, including molybdenum(Mo)‐based, tungsten(W)‐based, vanadium(V)‐based, titanium(Ti)‐based, cobalt(Co)‐based, and other catalysts. Initially, the mechanism of cyclohexene epoxidation by transition metal‐based catalysts is examined from the perspective of catalytic active centers. Subsequently, the current research of cyclohexene epoxidation catalysts is summarized based on the perspective of catalyst support. Additionally, the differences between alkyl hydroperoxide, hydrogen peroxide (H2O2), and oxygen (O2) as oxidants are analyzed. Finally, the main factors influencing catalytic performance are summarized, and reasonable suggestions for catalyst design are proposed. This work provides scientific support for the advancement of the olefin epoxidation industry. [ABSTRACT FROM AUTHOR]

Mordenite (MOR) has demonstrated potential as a catalyst for alkylation due to high variability, intrinsic porosity, and outstanding stability. However, the contact probability of benzene and methanol has been limited by typical layered structures of MOR and there is no connection between layers. Here, we report the preparedness of H‐MOR via a sequential post‐treatment method based on a commercial MOR. H‐MOR sample had appeared lattice imperfections inferred from characterization means. The samples were tested with benezene methylation reaction. Results show that the high conversion of benzene and the high selectivity of toluene were obtained from the miracle role of lattice imperfections in the H‐MOR sample. Sequentially, based on the study of all catalyst structure and physical properties, a plausible reaction mechanism for the selectivity of the desired toluene was proposed. [ABSTRACT FROM AUTHOR]

Enhancing the p-xylene (PX) yield for the process of direct crude to chemicals will keep more technological competitiveness and sustainable economics. However, the enhancement would be limited by the ratio of benzene ring to methyl groups in the feedstock. To maximize the PX capacity, the toluene methylation unit is integrated to the traditional aromatic complex with the low-cost methanol as additional feedstock. The detailed process modeling and simulation are presented for the mass balance, energy consumption and technoeconomic analyses. The results show that the PX yield is significantly improved by integrating toluene methylation unit and the additional methanol feedstock to break the limitations of ratio of benzene ring to methyl groups in the original feedstock. By comparing with the traditional aromatic complex, the PX product increases with a growth of 31.24% from 869.70 kmol·h−1 to 1140.92 kmol·h−1 for the methylation integrated process, and the effective utilization rate of benzene ring in the feedstock enhances from 65.74% to 86.23%. Under the minimum temperature difference of 10 °C, the integrated process reduces the unit energy consumption by 5.59% equaling 7.55% of standard oil. Besides, the integrated process needs less total capital investment but produces more annual sales revenues due to the high PX yield and low energy consumption, which exhibits more sensibility to the prices of feedstock and products and greater techno-economic performance than that of traditional aromatic complex. [Display omitted] • Aromatics complex integrated toluene methylation with low-cost methanol feedstock. • Methanol breaks the ratio limitations of benzene ring to methyl groups. • PX product increases 31.24% for the methylation integrated process. • Energy consumption for unit product reduces 5.59% for integrated process. • Integrated process exhibits greater techno-economic performance. [ABSTRACT FROM AUTHOR]

Cu/SiO2 catalyst prepared by the ammonia-evaporation (AE) method is the potential preferred catalyst for hydrogenation of dimethyl oxalate (DMO) to ethylene glycol (EG). Although significant advancements have been obtained in the confirmation and influence factors of active species in the hydrogenation process, the relationship between the catalytic activity and the sensitive factors in the preparation or pretreatment process of the catalyst is still uncertain. In this paper, Cu/ZSM-5 catalysts for DMO hydrogenation to EG were prepared by the AE method using ZSM-5 molecular sieve with high silicon-alumina ratio (1500) as a support. The ZSM-5 support was pretreated by drying at 393 K for different hours and it was found that the surface hydroxyl group of the support had significant influence on the structure and catalytic hydrogenation performance of the prepared Cu/ZSM-5 catalyst. The distribution of surface hydroxyl groups could be significantly changed by pre-drying the carrier, which further resulted in the change of the copper dispersion and surface properties of subsequent copper-supported catalysts. With the decrease of hydroxyl content on the surface of the ZSM-5 support, the prepared reduced Cu/ZSM-5 catalyst possessed smaller Cu0 particles size, higher copper dispersion, higher surface area of Cu0 and Cu+ species, but weakened surface acidity of the catalyst, which resulted in the great improvement of the catalytic activity. The DMO conversion and EG selectivity could reach 100% and 93% even under the low reaction temperature at 448 K over the Cu/ZSM-5-24 catalyst (based on the ZSM-5 support pretreated by drying for 24 h). In addition, the catalytic activity did not show obvious change after 300 h of reaction, probably due to the low temperature reaction and suitable surface properties of the catalyst. [ABSTRACT FROM AUTHOR]

TiO2 photocatalysis, as an energy‐saving, high‐efficiency and green technology, has a wide range of applications in sewage treatment, cancer treatment, hydrogen production, photocatalytic CO2 reduction and photocatalytic sensors. However, the large band width (Eg=3.2 eV) of TiO2 material hinders its practical application, which in turn leads to low visible‐light utilization and low quantum yield. Therefore, the preparation of TiO2 with high quantum yield and fast response to visible light has become a key topic in current photocatalyst research. This review discusses different photocatalytic applications, current synthetic techniques for the elaboration of nanostructures of several TiO2‐based materials and recent advances in enhancing visible photocatalytic activity. [ABSTRACT FROM AUTHOR]

A series of NiAlO composite oxide catalysts with high surface areas and high Ni dispersion were prepared through an improved co-precipitation method. The new preparation method effectively improved the specific surface area and pore volume of the catalyst, promoted the dispersion of nickel species, alleviated the agglomeration of the catalyst, and improved the stability of the catalyst by strengthening the interaction between Ni and Al. The typical catalyst Ni20Al had a specific surface area of 359 m2/g and a NiAl2O4 phase. In the dehydrogenation of methylcyclohexane over the Ni20Al catalyst, the conversion of methylcyclohexane could reach 77.4%, with toluene selectivity of 85.6%, and a hydrogen release rate of 63.94 mmol g−1 h−1, and did not show any significant inactivation during the stability test over 29 h under the reaction conditions of reaction temperature 450 °C and LHSV = 4 mL g−1 h−1. However, the conversion of methylcyclohexane with the IM-NiAl catalyst prepared through the traditional impregnation method was only 50.75%, with toluene selectivity of 70.5%, and with a hydrogen release rate of 35.84 mmol g−1 h−1, and the lifetime of the catalyst was only 15 h. [ABSTRACT FROM AUTHOR]

Porous bimetallic TiO 2 –Fe 2 O 3 composite nanofibers with different Fe 2 O 3 compositions (0–40 wt%) were prepared via a simple one-pot electrospinning approach. The surface areas, pore diameters, crystallinity and mesostructures of the bimetallic nanofibers were reasonably tuned by changing the Fe 2 O 3 compositions. A feasible mechanism of TiO 2 nanofiber modified with Fe 2 O 3 was proposed. The sensing results showed that TiO 2 –Fe 2 O 3 nanofibers with an appropriate Ti/Fe ratio exhibited much better Fenton activity than pure TiO 2 nanofibers. The best Fenton properties of methylene blue (MB) degradation were found for 60 wt% TiO 2 -40 wt% Fe 2 O 3 nanofibers, which formed a progressive TiO 2 /Fe 3 Ti 3 O 10 /Fe 2 O 3 triple-heterojunction and accelerated charge transfer and Fe3+/Fe2+ cycle reaction efficiency. More active sites were responsible for the high activity in the Fenton reaction. Porous bimetallic TiO 2 –Fe 2 O 3 composite nanofibers with different Ti/Fe ratio were prepared via a simple one-pot electrospinning approach. Pure nano-TiO 2 fiber had the smallest diameter but the largest particle size. Hence, it possessed a very low surface area because the large grains had to be confined to such a narrow range in fiber by compact and repetitive particle accumulation. TiO 2 fibers exhibited a good methylene blue (MB) degradation rate, which also indicated that TiO 2 itself can provide certain active sites. Thereafter, adding Fe 2 O 3 to TiO 2 can effectively adjust its structure and catalytic performance. When the doping amount of Fe 2 O 3 was 15%, the nanofiber diameter increased, and the particle size of TiO 2 decreased. The wide space can make TiO 2 particles uniformly dispersed, and there are many gaps among the grains. It can be seen from XRD and TEM that the TiO 2 particles were even dispersed, and Fe 2 O 3 particles were so small and homogeneous that they went undetected in XRD. These factors contributed to the rapid increase in its specific surface area. However, the Fenton activity decreased, probably due to too few Fe 2 O 3 active sites, the strong binding force between TiO 2 and Fe 2 O 3 to reduce the lattice oxygen mobility and prejudice redox reactions on the catalyst surface, and the active sites of TiO 2 were overlaid and passivated by Fe 2 O 3. As the iron content continued to increase to 40%, the fiber diameter decreased, and TiO 2 grains increased. The gradually enlarged grains were astricted by the fiber with reduced diameter, the dispersion of Ti–Fe particles was bound to slightly decrease compared with 85 wt%TiO 2 –15 wt%Fe 2 O 3 , the BET of bimetallic composite dropped but was larger than that of pure TiO 2 and mapping showed various elements still were evenly dispersed on the fiber. TiO 2 may be activated on the basis of H 2 -TPR results (reduction peak about pure TiO 2 was observed 580 °C, whereas reduction peak approximately 60 wt%TiO 2 –40 wt%Fe 2 O 3 was observed 515 °C, respectively.). XRD and TEM demonstrated that a new crystal phase Fe 3 Ti 3 O 10 appeared. It was believed that 60 wt%TiO 2 –40 wt%Fe 2 O 3 formed a progressive TiO 2 /Fe 3 Ti 3 O 10 /Fe 2 O 3 triple heterojunction, which accelerated the charge transfer and Fe3+/Fe2+ cycle reaction efficiency on surface of the catalyst, leading to a higher activity. [Display omitted] • TiO 2 -Fe 2 O 3 composite nanofibers (CNs) were synthesized by an electrospinning process. • The surface areas, fiber diameters and crystallinity of the TiO 2 -Fe 2 O 3 CNs are controlled by changing the iron content. • The CNs with appropriate Ti/Fe ratio exhibited a higher BET and much better Fenton activity than pure TiO 2. • The feasible mechanism of TiO 2 nano-fibers modified with Fe 2 O 3 was proposed. [ABSTRACT FROM AUTHOR]

Cathode materials LiNiMnO and LiNiLaMnO ( x = 0.04, 0.1, 0.14) were successfully prepared by the sol-gel self-combustion reaction (SCR) method. The X-ray diffraction (XRD) patterns indicated that, a few of doping La ions did not change the structure of LiNiMnO material. The scanning electronic microscopy (SEM) showed that the sample heated at 800°C for 12 h and then annealed at 600°C for 10 h exhibited excellent geometry appearance. A novel electrolyte system, 0.7 mol L lithium bis(oxalate)borate (LiBOB)-propylene carbonate (PC)/dimethyl carbonate (DMC) (1: 1, v/v), was used in the cycle performance test of the cell. The results showed that the cell with this novel electrolyte system performed better than the one with traditional electrolyte system, 1.0 mol L LiPF-ethylene carbonate (EC)/DMC (1: 1, v/v). And the electrochemical properties tests showed that LiNiLaMnO/Li cell performed better than LiNiMnO/Li cell at cycle performance, median voltage, and efficiency. [ABSTRACT FROM AUTHOR]

• Porous CoW oxide has high catalytic activity for the allylic oxidation of cyclohexene. • 79.8% cyclohexene conversion and 73.8% 2-cyclohexene-1-one selectivity are achieved. • Co site can promote effectively the cyclohexene allyl oxidation. • W site is conducive to the activation of the 2-cyclohexene 1-alcohol dehydrogenation. • Catalyst is easy to separate and has good cycling performance. The controllable oxidation of the allylic C H bond has great academic and industrial value. Different Co/W ratios of CoW composite oxides were prepared using hydrothermal method and used in the allylic oxidation reaction of cyclohexene containing unstable allylic hydrogen atoms and carbon-carbon double bonds. The relationship between the structure of active sites and catalytic performance was revealed using characterization techniques such as XRD, N 2 adsorption/desorption, SEM, TEM, FT-IR, UV–vis, and XPS. The results indicated that the Co(II)/Co(III) sites effectively mediate the first step of the entire oxidation reaction system, which generates hydroxyl radicals and peroxyl radicals through the activation of H 2 O 2 to achieve chain initiation. Subsequently, the cyclohexene underwent a series of chain migration reactions under the action of hydroxyl radicals and peroxyl radicals, resulting in the formation of 2-cyclohexen-1-one and 2-cyclohexen-1-ol. Finally, 2-cyclohexen-1-ol interacted with W(VI) sites to form 2-cyclohexen-1-one via an alcohol-coordinated hydroxyl intermediate. The tandem oxidation reaction of cyclohexene allylic oxidation and 2-cyclohexen-1-ol dehydrogenation was realized by the CoW synergistic catalytic. The synergy between Co and W sites, composed of Co-O-W units on the surface of the CoW oxide with porous channel features, was elucidated. The experimental results showed that under the optimal conditions, using CoW composite oxide (Co/ W = 1:1) as the catalyst, a 79.8% conversion rate of cyclohexene was achieved with 93.9% selectivity for the allylic products, among which the selectivity for 2-cyclohexen-1-one was 73.8%. The controllable oxidation of the allylic C H bond has great academic and industrial value. Co-W composite oxides were prepared using hydrothermal method and used in the allylic oxidation reaction of cyclohexene. This research indicated that the Co(II)/Co(III) sites effectively mediate the first step of the entire oxidation reaction system, which generates hydroxyl radicals and peroxyl radicals through the activation of H 2 O 2 to achieve chain initiation. Subsequently, the cyclohexene underwent a series of chain migration reactions under the action of hydroxyl radicals and peroxyl radicals, resulting in the formation of 2-cyclohexen-1-one and 2-cyclohexen-1-ol. Finally, 2-cyclohexen-1-ol interacted with W(VI) sites to form 2-cyclohexen-1-one via an alcohol-coordinated hydroxyl intermediate. The tandem oxidation reaction of cyclohexene allylic oxidation and 2-cyclohexen-1-ol dehydrogenation was realized by the CoW synergistic catalytic. [Display omitted] [ABSTRACT FROM AUTHOR]

Abstract: Mono-substituted Keggin-polyoxymetalate complex Na6 [SiW11ZnH2O40]·12H2O was demonstrated to be an effective catalyst for the selective oxidation of alcohols in the presence of hydrogen peroxide as oxidant. The reaction was carried out in an aqueous/oil biphasic system, which allowed easy recovery of catalyst, under relative mild conditions. The catalyst could be reused five times without appreciable loss of activity. [Copyright &y& Elsevier]

Vanadium oxyphosphate (VPO) with a high surface area was synthesized in a mixed solvent of ionic liquid [Bmim]Br and water, using phosphorous acid to reduce V5+ to V4+ and as a partial phosphorus source, and V2O5 as the vanadium source. The effects of ionic liquids on the synthesis process were investigated in detail. Using pure water as the solvent, the product was a vanadium phosphate compound with large flakes. With the increase in the amount of ionic liquid, the size of the large flakes of vanadium phosphate gradually decreased, and the morphology was changed to spherical particles. When the proportion of ionic liquid was 80% or the ionic liquid was solely used as the solvent, the VPO showed completely spherical particle morphology, and the specific surface area was the highest. X-ray diffraction analysis showed that the crystal phase of VPO changed from vanadium (IV) hydrogenphosphate hemihydrate (VOHPO4·0.5H2O) to an amorphous state with an increase in ionic liquid ratio. All of the above results show that ionic liquids play an important role in the synthesis of VPO materials. After being calcined in an n-butane/air atmosphere, the precursors were transformed into the vanadium pyrophosphate phase. The active VPO catalysts were used in the selective oxidation of cyclohexanol, and the yield of cyclohexanone was 57.98% for the VPO-80 catalyst synthesized using the ionothermal method but only 21.41% for the VPO-W catalyst synthesized using a traditional hydrothermal method, which shows the advantage of ionic liquid synthesis for VPO catalysts. Vanadium oxyphosphate material with high surface area was synthesized in the mixed solvent of ionic liquid [Bmim]Br and water. Ionic liquid plays an important role in the morphology and properties of synthesized VPO materials. The active VPO catalysts were used in the selective oxidation of cyclohexanol, and the yield of cyclohexanone was 57.98% for VPO-80 catalyst synthesized by ionothermal method, but only 21.41% for VPO-W catalyst synthesized by traditional hydrothermal method, which exhibited the advantages of ionic liquid synthesis for VPO catalysts. [ABSTRACT FROM AUTHOR]

A series of Gd/HZSM-5 catalysts were synthesized by incipient-wetness impregnation method and their surface properties and catalytic performances in methanol to hydrocarbons (MTH) reaction were studied in detail. The addition of gadolinium has little effect on the structure of zeolite and the specific surface area of catalyst. However, with the increase of Gd content, the strong acid density of catalysts shows a monotonously increasing trend and the Gd/HZSM-5 catalysts exhibit high C2–C5 aliphatic hydrocarbon selectivity in MTH reaction which can reach 71.6% over the catalysts with the gadolinium content of 7%. In addition, the Gd/HZSM-5 catalysts exhibit much lower carbon deposition rates than the parent HZSM-5 catalyst in MTH reaction due to the low yield of C9+ aromatics. Thus, the introduction of Gd into the HZSM-5 catalysts can significantly affect the amount of acid on the surface of catalyst, the distribution of reaction products and anticoking ability in MTH reaction. [ABSTRACT FROM AUTHOR]

• Co-Ni-Al layered double hydroxide was prepared via a simple coprecipitation method. • After calcination, the CoNiAlO mixed oxide with nanosheet structure was obtained. • The catalyst exhibits high efficiency in the selective oxidation of ethylbenzene. • It is attributed to the interactions between Co-Ni species and special structure. In this study, a series of Co–Ni–Al–layered double hydroxides (Co x Ni y Al 1 –LDHs) was successfully prepared via a simple co-precipitation method with Na 2 CO 3 and NaOH as the precipitants. After the calcination of the Co x Ni y Al 1 –LDH precursors, the Co–Ni–Al–O mixed oxides were formed and used as highly efficient catalysts in the selective oxidation of ethylbenzene to acetophenone. The Ni addition to CoAlO x can induce the formation of interactions between Co–Ni species and affect the dispersion of metal active centers, thereby greatly influencing the catalytic performance. The typical Co 2 Ni 1 Al 1 O x sample with a Co:Ni molar ratio of 2:1 exhibited the highest surface area (165 m2/g) and the best catalytic performance (80.0% ethylbenzene conversion and 88.9% acetophenone selectivity). The high catalytic efficiency was mainly attributed to the high-efficiency synergistic effect between the highly dispersed active center Co and the promoter Ni species. More importantly, the good recyclability and stability of the Co 2 Ni 1 Al 1 O x catalyst made it more competitive. A Co 2 Ni 1 Al 1 O x mixed oxide catalyst was obtained from the Co-Ni-Al layered double hydroxide precursor, which exhibited the high catalytic performance in the selective oxidation of ethylbenzene to acetophenone. [Display omitted] [ABSTRACT FROM AUTHOR]

Background: The alkylation of benzene with methanol is an important synthetic method that is widely used in various chemical production processes. However, obtaining a high selectivity for xylene and annihilating the MTO side reaction remain challenges. Results: In this work, a Ru/HZSM-5 catalyst was prepared using ZSM-5 as the precursor by a chemical precipitation method. Both XRD and TEM confirmed that Ru nanoparticles were evenly dispersed on the surface of the ZSM-5. The catalytic performance of benzene alkylation with methanol on the Ru/HZSM-5 catalyst was investigated. The results showed that the Ru/HZSM-5 catalyst could completely annihilate the MTO side reaction with a high conversion efficiency of benzene and selectivity for xylene, which resulted from the large gap between the transgression energy value of Ru and the ionization potential value of benzene, and the acidity of the catalyst changed greatly. Conclusion: These findings may offer not only a new and efficient multifunctional catalyst for benzene alkylation but also fundamental insight into the catalytic mechanism of the Ru/HZSM-5 catalyst. [ABSTRACT FROM AUTHOR]

In this work Si/HZSM-5-0.09M catalyst was prepared using desilication and regrowth of SiO2 method, which was characterized by XRF, XRD, SEM, NH3-TPD, and N2 adsorption/desorption. Meanwhile, the structure–activity relationship was comprehensively discussed. The results revealed that the aromatics total selectivity of Si/HZSM-5-0.09M catalyst was significantly improved, from 33 to 54.8% compared to HZSM-5 under the optimal conditions. Also, the selectivity of p-xylene over Si/HZSM-5-0.09M catalyst increased from 4.6 to 19.8% compared to HZSM-5. The total selectivity of benzene, toluene, and xylene over Si/HZSM-5-0.09M catalyst was significantly improved by 66.1% compared to that of HZSM-5. Thus, an excellent catalytic effect has been found, which indicates that the SiO2 deposition on the surface favors the enhancement of the p-xylene selectivity in the methanol aromatization reaction. [ABSTRACT FROM AUTHOR]

Background. Sang-Xing-Zhi-Ke-Fang (SXZKF) demonstrates good therapeutic effect against pharyngitis. Nevertheless, the pharmacological mechanism underlying its effectiveness is still unclear. Objective. To investigate the underlying mechanisms of SXZKF against pharyngitis using network pharmacology method. Methods. Bioactive ingredients of SXZKF were collected and screened using published literature and two public databases. Using four public databases, the overlapping genes between these bioactive compound-related and pharyngitis-related genes were identified by Venn diagram. Protein-protein interaction (PPI) was obtained using "Search Tool for the Retrieval of Interacting Genes (STRING)" database. "Database for Annotation, Visualization, and Integrated Discovery ver. 6.8 (DAVID 6.8)" was used to perform Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis to explore the molecular mechanisms of SXZKF against pharyngitis. Finally, Cytoscape 3.7.2 software was used to construct and visualize the networks. Result. A total of 102 bioactive compounds were identified. Among them, 886 compounds-related and 6258 pharyngitis-related genes were identified, including 387 overlapping genes. Sixty-three core targets were obtained, including ALB, PPARγ, MAPK3, EGF, and PTGS2. Signaling pathways closely related to mechanisms of SXZKF for pharyngitis were identified, including serotonergic synapse, VEGF signaling pathway, Fc epsilon RI signaling pathway, Ras signaling pathway, MAPK signaling pathway, and influenza A. Conclusion. This is the first identification of in-depth study of SXZKF against pharyngitis using network pharmacology. This new evidence could be informative in providing new support on the clinical effects of SXZKF on pharyngitis and for the development of personalized medicine for pharyngitis. [ABSTRACT FROM AUTHOR]

An extra-large-pore aluminophosphate molecular sieve with -CLO topology was successfully synthesized in low-dosage ionic liquids (ILs) via a simplified ionothermal route, for which all raw materials were firstly mixed together, and then ground into homogeneous gels followed by high-temperature crystallization. A representative -CLO-type sample was characterized by XRD, SEM, N 2 physisorption, TG-DSC, CHN elemental analysis and liquid 13C NMR. The results indicate that the synthesis of -CLO topology is through the co-structure directing effect of the ionic liquid 1-ethyl-3-methylimidazolium bromide and diisopropylamine. Moreover, the optimum synthetic conditions of this material were refined. It was found that the appropriate crystallization temperature and time are 190 °C and 2 h, respectively. Owing to the facile preparation procedure and low consumption of ionic liquids, the newly synthesized extra-large-pore -CLO molecular sieve may find potential application in related areas. Image 104271 • –CLO molecular sieve was ionothermally synthesized in low-dosage ionic liquids. • A new synergistic template was found for the synthesis of –CLO material. • A facile preparation procedure was developed to synthesize –CLO material. [ABSTRACT FROM AUTHOR]

The preparation of aromatic by methanol was the most effective way for rational utilization of resources. However, the catalyst for MTA reaction has not yet been successfully studied. Therefore, highly active and shape‐selective HZSM‐5 zeolite‐based catalysts were designed and synthesized by post‐treatments of desilication, dealumination, surface‐passivation and hydrothermal treatment tuning pore structure and acid amount and acid concentration of catalysts. XRD, SEM, TEM, BET, NH3‐TPD and Py‐IR were used for research and analysis the structure‐activity relationship between the catalysts and MTA reaction. The results showed that the total acid amount of catalyst shown a significant role in increasing the BTX selectivity. The selectivity of aromatics increased from 33 % to 58.1 % after hydrothermal treatment compared to the parent HZSM‐5 zeolite due to the decreased of total acid amount. Nevertheless the weak acid sites were crucial in increasing the p‐xylene selectivity. The selectivity of p‐xylene reached 63.8 % and 70.1 % after hydrothermal treatment and surface‐passivation due to the increased of weak acid sites, respectively. Modified HZSM‐5 zeolite‐base catalysts showed good application prospects in producing aromatics from methanol. [ABSTRACT FROM AUTHOR]

• Indirect and direct electrification of coal-to-methanol process are investigated. • Energy efficiency of the semi-electrification scenario reaches to 64.31 %. • Semi-electrification scenario achieves the minimum CO 2 emissions. • Total production cost of semi-electrification scenario is 301.0 $/t and a payback time of 4.13 years. • Fully-electrification scenario is not an ideal choice from comprehensive performances comparison. Electrification of traditional large-scale chemical industry based on renewable electricity can greatly reduce process CO 2 emission, and store intermittent renewable electricity into chemical products locally to decrease power grid frequency regulation caused by fluctuating renewable electricity. This study presents a framework for electrification of chemical industry from indirect and direct aspects using the state-of-art coal-to-methanol process as a case study. Traditional coal-to-methanol (Process 1) suffers from high CO 2 emission due to mismatch of H/C ratio between coal and methanol. A pulverized coal gasification-integrated SOEC process (Process 2) has been investigated, the water–gas-shift unit is avoided and a simplified acid gas removal process is implemented to replace traditional acid gas removal unit in Process 2. Electric heaters and heat pump system are applied in Process 2 as direct electrification methods to form semi-electrified scenario (Process 3). To discuss the effect of electrification levels on process performances, a fully electrified process (Process 4) is also designed. The results show that: CO 2 emissions of the four processes are 2.19, 0.71, 0.52 and 0.63 t/t MeOH, and energy efficiency are 57.40 %, 62.32 %, 64.31 % and 57.63 %, respectively. Production costs are 159.1, 294.3, 301.0 and 358.3 $/t MeOH, IRRs are 14, 31, 29 and 14.5 %, respectively. Through this research and analysis, we hope to explore integration potential of renewable electricity and traditional chemical industry, and design a greener methanol production route based on renewable electricity. [ABSTRACT FROM AUTHOR]

A high proportion of renewable energy integration will be one of the significant characteristics of future electric power grid, and power-to-NH 3 technologies will become an important approach for inter-quarter long-term energy storage. Meanwhile, as an important method of peak regulation in power systems, coal-based power plant is necessary to implement CO 2 capture. This study constructed a novel urea synthesis process based on renewable energy, including water electrolyzers, air separation, green ammonia, oxy-fuel combustion power plant, CO 2 purification, and urea synthesis units. Coal- and natural gas-based urea synthesis processes were selected as the contrasting processes.The results showed that CO 2 emissions from the novel process proposed in this work were 0.124–0.174 t CO 2 /t urea, which was much lower than that of the coal and natural gas-based urea processes (1.4 and 0.8 t CO 2 /t urea, respectively). In the current technical economy (with coal and natural gas prices of 450 CNY/t and 1.7 CNY/m3, respectively), the production cost of this new process was about 1.0–2.2 times higher than that of traditional processes. When the carbon tax values were 121 and 371 CNY/t, the total production costs of the natural gas- and coal-based urea process would exceed that of the new process, respectively. This study will provide a promising method for urea production based on renewable energy to realize CO 2 utilization from coal-fired power plant. [Display omitted] • A novel urea production process was proposed. • Energy efficiency of the novel process reached about 49.07%. • The novel process achieved reduced CO 2 emissions. • The novel process would be economic competitive in the future. [ABSTRACT FROM AUTHOR]

Carbon dioxide hydrogenation to produce methanol has the potential to liberate humanity from its reliance on fossil fuels, while simultaneously reducing carbon dioxide and developing the economy. This paper focuses on the effect of catalyst type and the process conditions such as temperature, pressure, H 2 /CO 2 feed ratio, and space velocity on CO 2 conversion and CH 3 OH selectivity. The net generated CO in the reaction system results in the loss of CO 2 and H 2 to the purge gas, which reduces the utilization efficiency of carbon and hydrogen. The specially designed catalysts and processes with recycling can improve CO 2 conversion and CH 3 OH selectivity, and the CO flow rate difference can be close to zero in the total recycling condition. Starting from these ideas, the two kinds of near-zero carbon emission processes with total recycling (respectively named total recycling process after flash separation and named total recycling process after stripping separation) are proposed. The utilization efficiency of carbon and hydrogen are similar in the two processes, but hot and cold utilities in the latter are 17.96% and 15.11% lower than in the former, respectively. Through the process integration between reaction heat and double-effect distillation, the energy consumption is further reduced in the total recycling process after stripping separation. The utilization efficiency of CO 2 is 99.88% in the total recycling process after stripping separation with double-effect distillation of the light split/reverse configuration, and the proposed process just requires cold utility. • Proposed a novel CO 2 -to-methanol process with near-zero carbon emission. • Carbon utilization efficiency of the proposed process is 99.88%. • Energy efficiency of the novel process is 90.54%. [ABSTRACT FROM AUTHOR]

Abstract Nickel phosphate (NiPO) nanofibers with high surface area (288 m2/g) were obtained from phosphoric acid and nickel nitrate in an ionic liquid ([Bmim]Br) via an ionothermal synthesis process at 150 °C. Heating the nanofibers under a H 2 atmosphere at 700 °C led to the formation of Ni 2 P nanorods, ~50 nm in diameter and 100–200 nm in length. The Ni 2 P nanorod catalyst exhibited a much higher turnover frequency in the hydrodesulfurization of dibenzothiophene than the previously reported Ni 2 P catalysts with nanoparticle, nanosheet or irregular block morphologies, which may be attributable to the morphology effect of the nanorods. Graphical abstract Unlabelled Image Highlights • Nickel phosphate nanofibers were obtained via an ionothermal synthesis process. • Heating the nanofibers in H 2 at 700 °C led to the formation of Ni 2 P nanorods. • The Ni 2 P nanorod catalyst exhibited high activity for the hydrotreating reactions. [ABSTRACT FROM AUTHOR]

Abstract Normally, higher conversion of benzene represented higher utilization rate of methanol. Given these problems, we have modified HZSM-5 with 3-aminopropyltriethoxysilane (AMEO) and the physical-chemistry properties of the catalysts were characterized by XRD, Zeta potential, Contact Angle Measurement, SEM, NH 3 -TPD and EDS. Meanwhile, the influence of AMEO addition on the catalytic performance of HZSM-5 for the alkylation of benzene with methanol was researched. Results show that HZSM-5 treated with AMEO, not only the selectivity of target product and the utilization of methanol for the alkylation of benzene with methanol were improved, but also the amount of coke was significant reduced. Graphical abstract Unlabelled Image Highlights • DMCS20-HZSM-5 was investigated for benzene alkylation. • DMCS20-HZSM-5 exhibited the highest selectivity of PX. • DMCS20-HZSM-5 exhibited a high methanol utilization. • The quantity of coke was greatly decreased over DMCS20-HZSM-5. [ABSTRACT FROM AUTHOR]

Abstract Iron-containing aluminophosphate molecular sieve with LEV topology (Fe-LEV molecular sieve) has been successfully synthesized by a microwave-assisted ionothermal method in low-dosage of eutectic mixture solvent, which is the first example of Fe incorporated aluminophosphates with the LEV-zeotype structure. The optimum synthetic conditions of this material were refined. The structure and morphology of a representative Fe-LEV sample, as well as the structure directing effect of eutectic mixture were thoroughly analyzed by various techniques including XRD, 27Al and 31P MAS NMR, ICP-AES, DR UV-Vis, ESR, XPS, N 2 adsorption/desorption, NH 3 -TPD, SEM, TEM, EDX, CHN elemental analysis, TG-DTA and FT-IR spectra. It was found that the combined effect of the starting precursor and a suitable structure-directing agent yielded an appropriate crystallization system of Fe-LEV molecular sieve, for which choline cations and intact tetraethylammonium bromide molecules were identified to be the structure-directing agents. The calcined Fe-LEV molecular sieve exhibits higher specific surface area and iron content, as well as a medium acidity and special hierarchical structure with both micropores and mesopores, implying that these zeolitic materials have a great potential in some industrially relevant applications. Graphical abstract Image 1 Highlights • The incorporation of iron into the framework of LEV-zeotype structure was achieved. • Fe-LEV zeolite was synthesized by microwave irradiation in low-dosage of eutectic mixture. • Choline cations and tetraethylammonium bromide molecules act as the SDAs. • Fast synthesis of Fe-LEV zeolite was achieved within 20 min. [ABSTRACT FROM AUTHOR]

The process of benzene/methanol alkylation reaction was studied thermodynamically based on functional group contribution method of Benson. Results show that ortho-xylene (OX), Ethyl-benzene (EB) and tri-methylbenzene (TMB) are the main byproduct in alkylation of benzene by methanol and the suppression of OX, EB and TMB over hierarchical porous HZSM-5 or other types of acidic solid catalysts still remains a great challenge. To overcome these limitations, we modified hierarchical ZSM-5 with ruthenium (Ru) to evaluate the alkylation of benzene with methanol in a fixed-bed continuous flow reactor. It was found that the presence of a small amount of Ru in ZSM-5 catalyst would largely suppress the formation of EB, reduce the selectivity of OX and TMB, and also extend greatly the live time of the catalyst. Alkylation of benzene by methanol: thermodynamics analysis for designing and designing for enhancing the selectivity of toluene and para-xylene.Graphical Abstract: Alkylation of benzene by methanol: thermodynamics analysis for designing and designing for enhancing the selectivity of toluene and para-xylene [ABSTRACT FROM AUTHOR]

ATN‐type FeAPO‐39 molecular sieves with high iron content has been successfully synthesized under non‐solvent conditions, which is the first example of iron‐incorporated aluminophosphate with the ATN‐zeotype structure. The optimum synthetic conditions of this material were refined. It was found that the following synthetic conditions, i.e. a low P2O5/Al2O3 ratio, a high DPA/Al2O3 ratio (DPA: di‐n‐propylamine) and an elevated crystallization temperature, seemed to be more favorable for the non‐solvent synthesis of ATN phase. The composition and structural characteristics of resultant relatively pure FeAPO‐39 molecular sieves were intensively studied by XRD, FT‐IR, TG‐DTA, CHN elemental analysis, ICP‐AES, SEM, TEM, N2 physisorption, UV/Vis diffuse reflectance spectroscopy and Mössbauer spectroscopy analyses. The iron content and zeolite yield of FeAPO‐39 material were found to be as high as 5.56 wt.‐% and 82.6 %, respectively. The results of FT‐IR, TG‐DTA and CHN elemental analysis indicate that DPA molecules may co‐direct the synthesis of ATN zeolites along with additional structure‐directing agent NH4+ ions resulting from iron source. Owing to the specific structure‐directing role provided by iron source, the synthetic strategy presented here may find a potential application in the non‐solvent synthesis of other aluminosilicate and aluminophosphate zeolites with novel frameworks. The incorporation of iron into the framework of ATN‐zeotype structure was achieved in non‐solvent system. DPA molecules and additional NH4+ ions resulting from iron compound act as the SDA. [ABSTRACT FROM AUTHOR]

[Display omitted] • Models of CTM with different CO 2 capture technologies are built and validated. • Techno-economic and environmental performances of CTM under different CO 2 capture technologies are analyzed and compared. • Low-carbon, efficient, and economically optimal carbon capture technology for green methanol synthesis is explored. • Improvement measures for sustainable development of CTM are proposed. CO 2 -to-methanol can realize the emissions reduction and resource utilization of CO 2. However, CO 2 capture technology will lead to energy and economic penalties of the whole methanol production process. Thus, the effect of different CO 2 capture technologies on the performance of the whole methanol production process is analyzed and compared in this study. A rigorous steady-state modeling and simulation of the four different CO 2 capture technologies (monoethanolamine (MEA), phase-change separation (PCS), dimethyl carbonate (DMC), and gas membrane separation (GMS)) are conducted, and the results are validated with literature data. Accordingly, the technical, economic, and environmental performances of the CO 2 -to-methanol process under different CO 2 capture technologies are analyzed to explore the low-carbon, efficient, and economically optimal carbon capture technology for green methanol synthesis. The results showed that the energy efficiency of the GMS case was the highest (68.4%), followed by PCS (66.2%), DMC (64.3%), and MEA (61.3%). The total production cost of the GMS case was the highest (4367 CNY/t-CH 3 OH), followed by MEA (4314 CNY/t-CH 3 OH), DMC (4279 CNY/t-CH 3 OH), and PCS (4204 CNY/t-CH 3 OH). All four cases achieved CO 2 emissions reductions. With the development of the third generation of biphasic absorbents, the PCS case improved the energy efficiency by 78.6%–83.8%. Thus, the PCS case was the optimal technology choice for achieving low-carbon, efficient, economic trade-offs in the commercial methanol production based on CO 2 capture and utilization. [ABSTRACT FROM AUTHOR]

The secondary reaction of toluene is difficult to be suppressed in benzene alkylation with methanol over conventional acidic zeolite catalysts. Moreover, the formation of coke yet remains a challenging problem. In this study, Na-Y zeolites were modified with ammonium carbonate (AC), citric acid (CA) and caesium nitrate(CN) to evaluate the alkylation of benzene with methanol, which was also characterized by XRD, SEM, FT-IR, N2 adsorption and Py-IR. For the Na-Y treated with AC-CA-CN, not only the catalytic selectivity for the alkylation of benzene with methanol was improved (the total selectivity of toluene and xylene was 97.9% and toluene selectivity was 86.4%), but also the quantity of coke was greatly decreased. [ABSTRACT FROM AUTHOR]

A series of Ru/NaY catalysts modified by a different amount of polyethylene glycol (PEG) were prepared using the impregnation-precipitation method and tested towards the reaction of paranitrotoluene (PNT) hydrogenation to p -methyl-cyclohexylamine (PMC). The various characterization techniques applied suggested that a suitable amount of PEG was responsible to reduce Ru nanoparticles size and enhance at the same time metallic Ru loading on the catalyst surface. A Ru-PEG 7.5 /NaY catalyst modified by 7.5 mL PEG showed a higher PNT conversion (> 99.9%) and reaction selectivity to PMC (95.2%) at 160 °C for 35 min compared to other Ru catalysts of different Ru/PEG molar ratio. The reusability of the Ru-PEG 7.5 /NaY catalyst was also investigated showing only slight deactivation due to Ru agglomeration. [ABSTRACT FROM AUTHOR]

[Display omitted] A series of MnMoP catalysts were prepared by ionic liquid assisted thermal synthesis method and characterized by Powder X-ray diffraction, Fourier Transform Infrared Spectrometer, Scanning Electron Microscope, X-ray Photoelectron Spectroscope and NH 3 -Temperature Programmed Desorption. The catalytic performance of MnMoP catalysts for the synthesis of cyclohexene oxide (CHO) was studied. The results showed that phosphorus was fixed via ionic liquid, which could improve the catalytic performance of the catalysts. Under the optimal conditions, MnMoP-80 catalyst showed the best catalytic performance with the cyclohexene conversion of 97.5% and CHO selectivity of 93.9%. Meanwhile, we have deduced that the reaction was mainly carried out according to the epoxidation pathway over MnMoP catalyst. [ABSTRACT FROM AUTHOR]

[Display omitted] • An absorbent screening method was established with SO 2 absorption capacity (α) and desorption reaction heat (Q des) value as indicators, and then amine-based absorbents with low Q des can be screened out. • The total regeneration energy consumption (Q tot) distribution of the four absorbents (MDEA-H 2 O, EDA-H 2 SO 4 -H 2 O, PZ-H 2 SO 4 -H 2 O, and HEP-H 2 SO 4 -H 2 O) were calculated, and the result showed that the latent heat consumption (Q lat) was the main reason for the high Q tot of the SO 2 capture process. • Three improved processes (the rich-split, the lean-flash heat pump and the top-steam heat pump processes) were designed to recover the energy available in the SO 2 capture process. • The top-steam heat pump case greatly reduced the Q lat of the SO 2 capture process, and the top-steam heat pump process with the PZ-H 2 SO 4 -H 2 O absorbent was the most energy saving potential process for the flue gas SO 2 capture. The high total regeneration energy consumption (Q tot) limits the industrial application of amine-based absorbent SO 2 capture technology, and regeneration energy consumption can be divided into desorption reaction heat (Q des), latent heat consumption (Q lat) and sensible heat consumption. This work focused on developing an energy-efficient SO 2 capture technology through amine-based adsorbent screening and process improvement, in which desorption reaction heat, being the internal cause of high regeneration energy consumption, was only related to the type of adsorbent. An absorbent screening method was established with SO 2 absorption capacity (α) and desorption reaction heat values as indicators. The screening results showed the functional relationship of Q des - α for five organic diamines ethylenediamine (EDA), piperazine (PZ), N-hydroxyethylpiperazine (HEP), N, N'-dihydroxyethylpiperazine (DIHEP), and N-hydroxyethyl-N'-hydroxypropylpiperazine (HEHPP)): according to α EDA > α PZ > α HEHPP > α HEP > α DIHEP , Q des(EDA) > Q des(PZ) > Q des(HEHPP) > Q des(DIHEP) > Q des(HEP). The latent heat consumption and sensible heat consumption were related to process configuration, and N-methyldiethanolamine (MDEA), EDA, PZ and HEP were screened as amine-based absorbers for process modeling. The energy analysis showed that the order for regeneration energy consumption of the four absorbents followed Q tot(MDEA) > Q tot(EDA) > Q tot(PZ) > Q tot(HEP) , and the energy distribution calculations showed that latent heat consumption had the largest proportion in regeneration energy consumption. Three improved processes (the rich-split, the lean-flash heat pump and the top-steam heat pump processes) were designed to recover the energy available in the system. Compared to the conventional process, the top-steam heat pump case could greatly reduce the regeneration energy consumption, and the Q tot values of the four absorbents (MDEA, EDA, PZ, and HEP) in the top-steam heat pump case were 4.28 GJ·t−1 SO 2 , 3.10 GJ·t−1 SO 2 , 3.13 GJ·t−1 SO 2 and 3.68 GJ·t−1 SO 2 , respectively. According to technical and economic analyses, the top-steam heat pump case under the PZ absorbent system had the most potential for the flue gas SO 2 capture process. [ABSTRACT FROM AUTHOR]

Ammonia is a very important chemical industry product. It has a wide range of applications in refrigeration, energy, and fertilizers, and 80% of ammonia is used as a nitrogen fertilizer. China mainly produces ammonia and urea from coal gasification, which leads to difficult CO 2 capture and high energy consumption. This study proposed a new process for the production of ammonia and urea by coal direct chemical looping hydrogen production process (CDCLTU). The coal direct chemical looping hydrogen production replaces the air separation unit and water gas conversion unit of the traditional coal-to-urea process (CTU), which effectively separates and captures CO 2 and significantly reduces the energy consumption. A model of the CDCLTU was established using Aspen Plus. Parameter optimization, technoeconomic, and environmental analysis were conducted through simulations. The results showed that CDCLTU could completely replace the air separation system that the CTU relies on. Compared with the traditional process, the utilization rate of C increased from 53.46% to 67.95% in the new process. The energy consumption of CO 2 separation and capture was reduced by 97.04%. The CDCLH had a 79.7% energy efficiency in the hydrogen production process and 99% capture rate of CO 2. The total capital investment was dropped by 41%, unit urea production cost dropped by 12.1%, and the payback period dropped from 7.5 to 3.5 years. This paper provides a new direction for clean and efficient utilization of coal resources. [Display omitted] • Proposed a novel coal-to-urea process by chemical looping technology. • Conducted main parameters optimization and performance analysis for the new process. • The new process reduced 97.04% energy consumption of CO 2 separation and capture. • Production cost of the new process is 12.1% lower than that of the conventional process. • The new process achieved 67.95% C utilization rate and 1.39 t/t lower CO 2 emission. [ABSTRACT FROM AUTHOR]