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This work proved that biomass-based polyols (sorbitol, xylitol, erythritol, glycerol and ethanediol) were able to be converted into high-value chemical (p-xylene) by catalytic cracking of polyols, alkylation of aromatics, and the isomerization of xylenes over the SiO2-modified zeolites. Compared to the conventional HZSM-5 zeolite, the SiO2-containing zeolites considerably increased the selectivity and yield of p-xylene due to the reduction of external surface acidity and the narrowing of pore entrance. The influences of the methanol additive, reaction temperature, and types of polyols on the selectivity and yield of p-xylene were investigated in detail. Catalytic cracking of polyols with methanol significantly enhanced the production of p-xylene by the alkylation of toluene with methanol. The highest p-xylene yield of 10.9 C-mol% with a p-xylene/xylenes ratio of 91.1% was obtained over the 15wt%SiO2/HZSM-5 catalyst. The reaction pathway for the formation of p-xylene was addressed according to the study of the key reactions and the characterization of catalysts.

There are few reports on the near-field acoustic signals corresponding to lightning return strokes. One rocket-triggered lightning flash, which contains 13 return strokes, initial continuous current (ICC) processes, and abundant M-components, was observed in the summer of 2018 and reported in this study. The complete near-field acoustic pressure signals initiated by the flash were recorded and analyzed. It is found that the near-field acoustic pressure signals from each return stroke are composed of the first arrived N-shape shock waveform and the subsequent low-frequency oscillating waveforms. The characteristic of the acoustic waveforms has been parametrically defined and quantitatively analyzed, with a comprehensively acoustic-electrical correlation investigation. The acoustic pressure signals from intensive ICC processes and M-component pulses with different discharge intensities are also discussed. It is found that the too-close time interval between M-component and previous current pulses would affect the generation and measurement of the acoustic pressure waveforms from the M-component, even though the discharge amplitude is competitive and the wavefront is fast. The same phenomenon has also been observed in the acoustic signals from a return stroke with a too close interval from the previous pulse. The acoustic source localization with great accuracy for lightning channel reconstruction was realized based on the measured acoustic signals. The reconstructed channel structure agrees with that of the synchronously captured optical image. The study of the characteristics of acoustic signals from lightning discharge contributes to the recognition of thunder signals, source localization for channel reconstruction, and understanding of the lightning discharge process.

This work developed a one-step process for renewable p-xylene production by co-catalytic fast pyrolysis (co-CFP) of cellulose and methanol over the different metal oxides modified ZSM5 catalysts. It has been proven that ${\rm{L}}{{\rm{a}}_{\rm{2}}}{{\rm{O}}_{\rm{3}}}$ -modified ZSM5(80) catalyst was an effective one for the production of bio-based p-xylene. The selectivity and yield of p-xylene strongly depended on the acidity of the catalysts, reaction temperature, and methanol content. The highest p-xylene yield of 14.5 C-mol% with a p-xylene/xylenes ratio of 86.8% was obtained by the co-CFP of cellulose with 33wt% methanol over 20% ${\rm{L}}{{\rm{a}}_{\rm{2}}}{{\rm{O}}_{\rm{3}}}$ -ZSM5(80) catalyst. The deactivation of the catalysts during the catalytic pyrolysis process was investigated in detail. The reaction pathway for the formation of p-xylene from cellulose was proposed based on the analysis of products and the characterization of catalysts.

Lignin only accounts for about 6% of total mass in tobacco stem, but it influences the harmful substances in the side stream smoke of cigarette in a significant way. Traditional researches focus only on the determination of lignin content. In the present work, we investigate four typical imidazolium-based ionic liquids for efficient extraction of lignin under mild conditions and 1-ethyl-3-methylimidazolium diethylphosphate ([Emim][DEP]) shows the best results. The pretreatment of stem using water at 80 °C for 30 min can not only remove most of the sugars but also loose the microfibers. The extractive rate of lignin reaches 85.38% at 150 °C for 4 h and the purity of lignin is 90.21%.

In the present work, we reported a novel route for the conversion of lignocellulosic biomass (sawdust) to a high-value chemical of benzoic acid under atmospheric pressure. The transformation involved the catalytic pyrolysis of sawdust into aromatics, the decomposition of heavier alkylaromatics to toluene, and the liquid-phase oxidation of toluene-rich aromatics to benzoic acid. The production of the desired benzoic acid from the sawdust-derived aromatics, with the benzoic acid selectivity of 85.1 C-mol% and nearly complete conversion of toluene, was achieved using the MnO2/NHPI catalyst at 100 °C for 5 h. The influence of adding methanol on the catalytic conversion of sawdust to the core intermediate of toluene was also investigated in detail.

The directional production of benzene is achieved by the current-enhanced catalytic conversion of lignin. The synergistic effect between catalyst and current promotes the depolymerization of lignin and the selective recombinant of the functional groups in the aromatic monomers. A high benzene yield of 175 gbenzene/kglignin was obtained with an excellent selectivity of 92.9 C-mol%. The process potentially provides a promising route for the production of basic petrochemical materials or high value-added chemicals using renewable biomass.

Cumene is an important intermediate and chemical in chemical industry. In this work, directional preparation of cumene using lignin was achieved by a three-step cascade process. The mixture aromatics were first produced by the catalytic pyrolysis of lignin at 450 °C over 1%Zn/HZSM-5 catalyst, monocyclic aromatics with the selectivity of 85.7 wt% were obtained. Then, the catalytic dealkylation of heavier aromatics resulted in benzene-rich aromatics with 93.6 wt% benzene at 600 °C over Hβ catalyst. Finally, the cumene synthesis was performed by the aromatic alkylation, giving cumene selectivity of 91.6 C-mol% using the [bmim]Cl-2AlCl3 ionic liquid at room temperature for 15 min. Besides, adding a small amount of methanol to the feed can efficiently suppress the coke yield and enhance the aromatics yield. The proposed transformation potentially provides a useful route for production of cumene using renewable lignin.

In recent years, production of engine fuels and energy from biomass has drawn much interest. In this work, we conducted a novel integrated process for the preparation of bio-hydrogen and bio-fuels using lignocellulosic biomass pyrolysis-oil (bio-oil). The process includes (i) the production of bio-hydrogen or bio-syngas by the catalytic cracking of bio-oil, (ii) the adjustment of bio-syngas, and (iii) the production of bio-fuels by olefinic polymerization (OP) together with Fischer-Tropsch synthesis (FTS). Under the optimal conditions, the yield of bio-hydrogen was 120.9 g H2/(kg bio-oil). The yield of hydrocarbon bio-fuels reached 526.1 g/(kg bio-syngas) by the coupling of OP and FTS. The main reaction pathways (or chemical processes) were discussed based on the products observed and the catalyst property.

The continual growth in transportation fuels and more strict environmental legislations have led to immense interest in developing green biomass energy. In this work, a proposed catalytic transformation of oxygenated organic compounds (related to bio-oil) into pure hydrogen was desighed, involving the catalytic reforming of oxygenated organic compounds to hydrogen-rich mixture gas followed by the conversion of CO to CO2 via the water gas reaction and the removal of CO2. The optimization of the different reforming catalyst, the reaction conditions as well as various sources of oxygenated organic compounds were investigated in detail. The production of pure hydrogen, with the H2 content up to 99.96% and the conversion of 97.1%, was achieved by the integrated catalytic transformation. The reaction pathways were addressed based on the investigation of decomposition, catalytic reforming, and the water gas reaction.

A series of bifunctional catalysts composed of a component for higher alcohol synthesis (CuCoMn oxides, CCM) and an acidic zeolite (SAPO-34, ZSM-5, Y, MCM-41) were prepared for production of liquid hydrocarbon directly from a bio-syngas through a one-stage process. The effects of zeolite type, zeolite content, Si/Al ratio and preparation method on catalyst texture and its reaction performance were investigated. Higher selectivities and yields of liquid products were obtained by using bifunctional catalysts. The yields of liquid hydrocarbons decreased in the order CCM-ZSM-5>CCM-SAPO-34>CCM-Y>CCM-MCM-41. CCM-ZSM-5 (20wt%, Si/Al=100) prepared by coprecipitation method displayed the optimal catalytic performance with the highest CO conversion (76%) and yield of liquid products (30%). The catalysts were characterized by N2 adsorption/desorption, NH3-TPD, XRD, and H2-TPR analysis. The results showed that higher specific surface areas and pore volumes of bifunctional catalysts were achieved by adding zeolites into CuCoMn precursors. Medium pore dimension and moderate acidity in CCM-ZSM-5 were observed, which probably resulted in its excellent reaction performance. Additionally, a higher number of weaker acid sites (weak and/or medium acid sites) were formed by increasing ZSM-5 content in CCM-ZSM-5 or decreasing Si/Al ratio in ZSM-5. It was also seen that metal dispersion was higher and reducibility of metal ions was easier on the CCM-ZSM-5 catalyst prepared by coprecipitation. The higher alcohols-to-hydrocarbon process provides a promising route to hydrocarbon fuels via higher alcohols from syngas or biobased feedstocks.

A series of surfactant-modified CuCoMn-based catalysts were prepared for higher alcohol synthesis from biomass-based syngas. Three typical surfactants, cetyltrimethylammonium bromide (CTAB), sodium dodecyl sulfate (SDS) and pluronic P123 triblock copolymer (EO20PO70EO20), were employed. Compared to surfactant-free CuCoMn catalyst, CO conversion increased from 17.4% to 29.7% over SDS-modified CuCoMn catalyst, and the selectivity of higher alcohols increased from 22.0% to 41.2% over CTAB-modified catalyst. Besides, the proportions of higher alcohols in total alcohols increased over all surfactant-modified catalysts. The catalysts were characterized by N2 adsorption/desorption, XRD, XPS and IR analysis. The results showed that several more favorable features rendered the CTAB-modified CuCoMn catalyst to be suitable for higher alcohol production, such as the larger pore size, better crystallinity of CuCoMnO4 spinel, moderate surface atomic distribution and lower valence of metallic ions. In addition, it was verified that CTAB addition at the metal precipitation stage was beneficial to higher alcohol synthesis. Surfactant-induced modification provides a promising alternative method for catalyst improvement in synthesis of higher alcohols.

Lignin is the only nature renewable resource which can provide large quantities of aromatic compounds. In the work, transformation of lignin into benzene, toluene, and xylenes (BTX) was investigated over the HZSM-5, HY, and MCM-22 catalysts, and the HZSM-5 catalyst showed the highest carbon yield of BTX. The reaction condition, including temperature, the gas flow rate, and the catalyst/lignin ratio, was also investigated. The carbon yield of BTX reached about 25.3 C-mol% over HZSM-5 catalyst under T=550 °C, f(N2)=300 cm3/min, and catalyst/lignin ratio of 2.

Low‐carbon light olefins are the basic feedstocks for the petrochemical industry. Catalytic cracking of crude bio‐oil and its model compounds (including methanol, ethanol, acetic acid, acetone, and phenol) to light olefins were performed by using the La/HZSM‐5 catalyst. The highest olefins yield from crude bio‐oil reached 0.19 kg/(kg crude bio‐oil). The reaction conditions including temperature, weight hourly space velocity, and addition of La into the HZSM‐5 zeolite can be used to control both olefins yield and selectivity. Moderate adjusting the acidity with a suitable ratio between the strong acid and weak acid sites through adding La to the zeolite effectively enhanced the olefins selectivity and improved the catalyst stability. The production of light olefins from crude bio‐oil is closely associated with the chemical composition and hydrogen to carbon effective ratios of feedstock. The comparison between the catalytic cracking and pyrolysis of bio‐oil was studied. The mechanism of the bio‐oil convers...

A new kind of multiple metal (Cu, Mg, Ce) doped Ni based mixed oxide catalyst, synthesized by the co‐precipitation method, was used for efficient production of hydrogen from bio‐oil reforming at 250–500 °C. Two reforming processes, the conventional steam reforming (CSR) and the electrochemical catalytic reforming (ECR), were performed for the bio‐oil reforming. The catalyst with an atomic mole ratio of Ni : Cu : Mg : Ce : Al =5.6:1.1:1.9:1.0:9.9 exhibited very high reforming activity both in CSR and ECR processes, reaching 82.8% hydrogen yield at 500 °C in the CSR, yield of 91.1% at 400 °C and 3.1 A in the ECR, respectively. The influences of reforming temperature and the current through the catalyst in the ECR were investigated. It was observed that the reforming and decomposition of the bio‐oil were significantly enhanced by the current. The promoting effects of current on the decomposition and reforming processes of bio‐oil were further studied by using the model compounds of bio‐oil (acetic acid and ethanol) under 101 kPa or low pressure (0.1 Pa) through the time of flight analysis. The catalyst also shows high water gas shift activity in the range of 300–600 °C. The catalyst features and alterations in the bio‐oil reforming were characterized by the ICP, XRD, XPS and BET measurements. The mechanism of bio‐oil reforming was discussed based on the study of the elemental reactions and catalyst characterizations. The research catalyst, potentially, may be a practical catalyst for high efficient production of hydrogen from reforming of bio‐oil at mild‐temperature.

Catalytic conversion of bio-oil into light olefins was performed by a series of molecular sieve catalysts, including HZSM-5, MCM-41, SAPO-34 and Y-zeolite. Based on the light olefins yield and its carbon selectivity, the production of light olefins decreased in the following order: HZSM-5>SAPO-34>MCM-41> Y-zeolite. The highest olefins yield from bio-oil using HZSM-5 catalyst reached 0.22 kg/kgbio-oil with carbon selectivity of 50.7% and a nearly complete bio-oil conversion. The reaction conditions and catalyst characterization were investigated in detail to reveal the relationship between the catalyst structure and the production of olefins. The comparison between the pyrolysis and catalytic pyrolysis of bio-oil was also performed.

Autothermal steam reforming (ATR) of bio-oil, which couples the endothermic steam reforming reaction with the exothermic partial oxidation, offers many advantages from a technical and economic point of view. Effective production of hydrogen through ATR of bio-oil was performed at lower temperature with NiCuZnAl catalyst. The highest hydrogen yield from bio-oil reached 64.3% with a nearly complete bio-oil conversion at 600 °C, the ratio of steam to carbon fed (S/C) of 3 and the oxygen to carbon ratio (O/C) of 0.34. The reaction conditions in ATR including temperature, O/C, S/C and weight hourly space velocity can be used to control both hydrogen yield and products distribution. The comparison between the ATR and common steam reforming of bio-oil was studied. The mechanism of the ATR of bio-oil was also discussed.

Highly efficient synthesis of clean biofuels using the bio-syngas obtained from biomass gasification was performed over Fe1.5Cu1Zn1Al1K0.117 catalyst. The maximum biofuel yield from the bio-syngas reaches about 1.59 kg biofuels/(kgcatal·h) with a contribution of 0.57 kg alcohols/(kgcatal·h) and 1.02 kg liquid hydrocarbons/(kgcatal·h). The alcohol products in the resulting biofuels were dominated by the C2+ alcohols (mainly C2—C6 alcohols) with a content of 73.55%–89.98%. The selectivity of the liquid hydrocarbons (C5+) in the hydrocarbon products ranges from 60.37% to 70.94%. The synthesis biofuels also possess a higher heat value of 40.53–41.49 MJ/kg. The effects of the synthesis conditions, including temperature, pressure, and gas hourly space velocity, on the biofuel synthesis were investigated in detail. The catalyst features were characterized by inductively coupled plasma and atomic emission spectroscopy, X-ray diffraction, temperature programmed reduction, and the N2 adsorption-desorption isotherms measurements. The present biofuel synthesis with a higher biofuel yield and a higher selectivity of liquid hydrocarbons and C2+ alcohols may be a potentially useful route to produce clean biofuels and chemicals from biomass.

A dual-reactor, assembled with the on-line syngas conditioning and methanol synthesis, was successfully applied for high efficient conversion of rich CO2 bio-oil derived syngas to bio-methanol. In the forepart catalyst bed reactor, the catalytic conversion can effectively adjust the rich-CO2 crude bio-syngas into the CO-containing bio-syngas using the CuZnAlZr catalyst. After the on-line syngas conditioning at 450 °C, the CO2/CO ratio in the bio-syngas significantly decreased from 6.3 to 1.2. In the rearward catalyst bed reactor, the conversion of the conditioned bio-syngas to bio-methanol shows the maximum yield about 1.21 kg/(kgcatal·h) MeOH with a methanol selectivity of 97.9% at 260 °C and 5.05 MPa using conventional CuZnAl catalyst, which is close to the level typically obtained in the conventional methanol synthesis process using natural gas. The influences of temperature, pressure and space velocity on the bio-methanol synthesis were also investigated in detail.

We reports an efficient approach for production of hydrogen from crude bio-oil and biomass char in the dual fixed-bed system by using the electrochemical catalytic reforming method. The maximal absolute hydrogen yield reached 110.9 g H2/kg dry biomass. The product gas was a mixed gas containing 72%H2, 26%CO2, 1.9%CO, and a trace amount of CH4. It was observed that adding biomass char (a by-product of pyrolysis of biomass) could remarkably increase the absolute H2 yield (about 20%-50%). The higher reforming temperature could enhance the steam reforming reaction of organic compounds in crude bio-oil and the reaction of CO and H2O. In addition, the CuZn-Al2O3 catalyst in the water-gas shift bed could also increase the absolute H2 yield via shifting CO to CO2.

We provides a novel approach to generate low-temperature atomic oxygen anions (O?) emission using the cesium oxide-doped 12CaO?7Al2O3 (Cs2O-doped C12A7). The maximal emission intensity of O? from the Cs2O-doped C12A7 at 700 ?C and 800 V/cm reached about 0.54 ?A/cm2, which was about two times as strong as that from the un-doped C12A7 (0.23 ?A/cm2) under the same condition. The initiative temperature of the O? emission from the Cs2O-doped C12A7 was about 500 ?C, which was also much lower than the initiative temperature from the un-doped C12A7 (570 ?C) in the given field of 800 V/cm. High pure O? emission close to 100% could be obtained from the Cs2O-doped C12A7 under the lower temperature (

We investigated high catalytic activity of Ni/HZSM-5 catalysts synthesized by the impregnation method, which was successfully applied for low-temperature steam reforming of bio-oil. The influences of the catalyst composition, reforming temperature and the molar ratio of steam to carbon fed on the stream reforming process of bio-oil over the Ni/HZSM-5 catalysts were investigated in the reforming reactor. The promoting effects of current passing through the catalyst on the bio-oil reforming were also studied using the electrochemical catalytic reforming approach. By comparing Ni/HZSM-5 with commonly used Ni/Al2O3 catalysts, the Ni20/ZSM catalyst with Ni-loading content of about 20% on the HZSM-5 support showed the highest catalytic activity. Even at 450 °C, the hydrogen yield of about 90% with a near complete conversion of bio-oil was obtained using the Ni20/ZSM catalyst. It was found that the performance of the bio-oil reforming was remarkably enhanced by the HZSM-5 supporter and the current through the catalyst. The features of the Ni/HZSM-5 catalysts were also investigated via X-ray diffraction, inductively coupled plasma and atomic emission spectroscopy, hydrogen temperature-programmed reduction, and Brunauer-Emmett-Teller methods.

A series of Mo-based catalysts prepared by sol-gel method using citric acid as complexant were successfully applied in the high efficient production of mixed alcohols from bio-syngas, derived from the biomass gasification. The Cu1Co1Fe1Mo1Zn0.5−6%K catalyst exhibited a higher activity on the space-time yield of mixed alcohols, compared with the other Mo-based catalysts. The carbon conversion significantly increases with rising temperature below 340 °C, but the alcohol selectivity has an opposite trend. The maximum mixed alcohols yield derived from biomass gasification is 494.8 g/(kgcatal·h) with the C2+ (C2—C6 higher alcohols) alcohols of 80.4% under the tested conditions. The alcohol distributions are consistent with the Schulz-Flory plots, except methanol. In the alcohols products, the C2+ alcohols (higher alcohols) dominate with a weight ratio of 70%–85%. The Mo-based catalysts have been characterized by X-ray diffraction and N2 adsorption/desorption. The clean bio-fules of mixed alcohols derived from ...

The reforming of anisole (as model compound of bio-oil) was performed over the NiCuZn-Al2O3 catalyst, using a recently-developed electrochemical catalytic reforming (ECR). The influence of the current on the anisole reforming in the ECR process has been investigated. It was observed that anisole reforming was significantly enhanced by the current approached over the catalyst in the electrochemical catalytic process, which was due to the non-uniform temperature distribution in the catalytic bed and the role of the thermal electrons originating from the electrified wire. The maximum hydrogen yield of 88.7% with a carbon conversion of 98.3% was obtained through the ECR reforming of anisole at 700°C and 4 A. X-ray diffraction was employed to characterize catalyst features and their alterations in the anisole reforming. The apparent activation energy for the anisole reforming is calculated as 99.54 kJ/mol, which is higher than ethanol, acetic acid, and light fraction of bio-oil. It should owe to different physical and chemical properties and reforming mechanism for different hydrocarbons.

High-efficient production of hydrogen from bio-oil was performed by electrochemical catalytic reforming method over the CoZnAl catalyst. The influence of current on the hydrogen yield, carbon conversion, and products distribution were investigated. Both the hydrogen yield and carbon conversion were remarkably enhanced by the current through the catalyst, reaching hydrogen yield of 70% and carbon conversion of 85% at a lower reforming temperature of 500°C. The influence of current on the properties of the CoZnAl catalyst was also characterized by X-ray diffraction, X-ray photoelectron spectroscopy, thermal gravimetric analysis, and Brunauer-Emmett-Teller measurements. The thermal electrons would play an important role in promoting the reforming reactions of the oxygenated-organic compounds in the bio-oil.

A storage and emission functional material of [Ca24Al28O64]4+(Cl)3.80(O2)0.10 (C12A7-Cl), was prepared by the solid-state reactions of CaCO3, -Al2O3, and CaCl2 in Cl2/Ar mixture atmosphere. The anionic species stored in the C12A7-Cl material were dominated by Cl, about (2.210.24) 1021 cm3, accompanied by a small amount of O2, O, and O2, measured via ion chromatography, electron paramagnetic resonance, and raman spectra measurements. These results also corroborate identification of time-of-flight mass spectroscopythe anionic species emitted from the C12A7-Cl surface were dominated by the Cl (about 90%) together with a small amount of O and electrons. The structure and morphological alterations of the material were investigated via X-ray diffraction and field emission scanning electron microscope, respectively.

Highly effective production of hydrogen from bio-oil was achieved by using a low-temperature electrochemical catalytic reforming approach over the conventional Ni-based reforming catalyst (NiO-Al2O3), where an AC electronic current passed through the catalyst bed. The promoting effects of current on the bio-oil reforming were studied. It was found that the performance of the bio-oil reforming was remarkably enhanced by the current which passed through the catalyst. The effects of currents on the microcosmic properties of the catalyst, including the BrunauerEmmettTeller (BET) surface area, pore diameter, pore volume, the size of the crystallites and the reduction level of NiO into Ni, were carefully characterized by BET, X-ray diffraction, X-ray photoelectron spectroscopy, and scanning electron microscope. The desorption of the thermal electrons from the electrified catalyst was directly observed by the TOF (time of flight) measurements. The mechanism of the electrochemical catalytic reforming of bio-oil is discussed based on the above investigation.

The effects of potassium addition and the potassium content on the activity and selectivity of coprecipitated iron catalyst for Fischer-Tropsch synthesis (FTS) were studied in a fixed bed reactor at 1.5 MPa, 300C, and contact time (W/F) of 12.5 gcath/mol using the model bio-oil-syngas of H2/CO/CO2/N2 (62/8/25/5, vol%). It was found that potassium addition increases the catalyst activity for FTS and the reverse water gas shift reaction. Moreover, potassium increases the average molecular weight (chain length) of the hydrocarbon products. With the increase of potassium content, it was found that CH4 selectivity decreases and the selectivity of liquid phase products (C5+) increases. The characteristics of FTS catalysts with different potassium content were also investigated by various characterization measurements including X-ray diffraction, X-ray photoelectron spectroscopy and Brunauer-Emmett-Teller surface area. Based on experimental results, 100Fe/6Cu/16Al/6K (weight ratio) was selected as the optimal catalyst for FTS from bio-oil-syngas. The results indicate that the 100Fe/6Cu/16Al/6K catalyst is one of the most promising candidates to directly synthesize liquid bio-fuel using bio-oil-syngas.

The benzene conversion and phenol selectivity from C6H6/O2/H2O over [Ca24Al28O64]4+4O(C12A7-O) catalyst were investigated using a flow reactor. The benzene conversion increases with the increase of temperature, and the phenol selectivity mainly depends on both reaction temperature and the composition of the mixtures. The changes of the catalyst structure before and after the reactions and the intermediates on the catalyst surface and in the bulk were investigated by XRD, EPR and FT-IR. The catalytic reactions do not cause any damage to the structure of the positively charged lattice framework C12A7-O, but part of the O and O2 species in the bulk of C12A7-O translate to OH after the reactions. The neutral species and anion intermediate were investigated by Q-MS and TOF-MS respectively. It is suggested that the active O and OH species played a key role in the process of phenol formation.

A novel NOx storage/reduction catalyst 12CaO7Al2O3/10%K, defined as C12A7/K, was prepared, which possesses good NOx storage/reduction ability with a high sulfur-tolerance. The effect of H2O on the NO reduction features over the C12A7/K catalyst was investigated. The NO conversion and the N2 selectivity were measured as a function of temperature and H2O concentration. In the presence of 1.2% H2O, both the NO conversion and the N2 selectivity significantly decrease at lower temperature region ( 500C). At temperatures over 500C, however, the NO reduction is only slightly influenced by H2O. The species of NO3/NO2 are confirmed as main storage components in the C12A7/K catalyst, which are further reduced into N2 by H2 under the reduction conditions.

NS+ was detected from ionization of the final product of the N(2D)+SF2 reaction by laser multiphoton ionization. NS is not the spectral carrier of our REMPI (resonance-enhanced multiphoton ionization) spectrum. For understanding the experimental facts and to obtain a complete description of the whole process, quantum-chemical calculations were performed. The density functional theory/Becke’s three-parameter hybrid-function calculations indicate that NSF is the product of the most favorable channel of the N+SF2 reaction. The complete active space self-consistent field (CASSCF) potential energy curve calculations predict that 1 1A″ is a predissociative state of NSF with the NS radical and F atom as the dissociation products. The CASSCF vibrational frequencies calculated at the 1 1A″ minimum are in line with the excitation spectrum. The CASPT2 adiabatic excitation energy value of 3.32 eV for the 1 1A″ state is close to the energy value (3.44 eV) of one photon. On the basis of theoretical calculations, it is ...

Hydrogen production by catalytic steam reforming of the bio-oil, naphtha, and CH4 was investigated over a novel metal-doped catalyst of (Ca24Al28O64)4+4O/Mg (C12A7-Mg). The catalytic steam reforming was investigated from 250 to 850C in the fixed-bed continuous flow reactor. For the reforming of bio-oil, the yield of hydrogen of 80% was obtained at 750C, and the maximum carbon conversion is nearly close to 95% under the optimum steam reforming condition. For the reforming of naphtha and CH4, the hydrogen yield and carbon conversion are lower than that of bio-oil at the same temperature. The characteristics of catalyst were also investigated by XPS. The catalyst deactivation was mainly caused by the deposition of carbon in the catalytic steam reforming process.

V–E energy transfer in C2H4 and alkali gas system C2H‡4+M→C2H4+M*(M=Na, K, Rb, and Cs, ‡ denotes high vibrationally excited state, * denotes electronically excited state) was investigated by using IR multiphoton excitation of C2H4 and probing the atomic fluorescence due to the above process. The atomic decay rates were determined as a function of alkali or ethylene gas concentration. The rate constants of V–E energy transfer were originally obtained by comparing the decay rate under different experimental conditions with the solution of the set of equations based on a proposed kinetic model. The kinetic information with respect to the inverse E–V energy transfer and the deexcitation process of the highly vibrationally excited state C2H‡4 were also obtained which agreed well with the results obtained from other methods. The large cross sections of the V–E energy transfer and their weak dependence on temperature obtained were interpreted based on a harpooning mechanism.

Strong and high purity O− negative ion emission has been observed from a synthesized crystal 12CaO⋅7Al2O3 surface. A μA/cm2-level O− emission from this material has been achieved at the surface temperature of 800 °C and the extraction field over 1000 V/cm, which is about three orders of magnitude higher than the current density emitted from the Y2O3-stabilized ZrO2 electrolyte surface. The strong emissivity of this material, as well as easy and economical fabrication, may provide a useful tool to generate the O− negative ion, which is expected to be one of the most important radicals for chemical syntheses and material modifications.

By using an anion-exchanging method, about 90% of the O− anions in the C12A7‐O− microporous crystal ([Ca24Al28O64]4+∙4O−) have been substituted primarily by the H− anions, leading to the successful formation of a new H− emission material, C12A7‐H−([Ca24Al28O64]4+∙4H−). A sustainable and stable emission of H−, in a current density of μA∕cm2 level, has been obtained by supplying H2 and electrons on the backside of the C12A7‐H− sample. The emission features of C12A7‐H−, including temperature and field effects, have been investigated. It is expected that the present material could be practically used as an H− anion generator.