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This work aimed to develop an integrated process for production of gasoline fraction bio-fuels from bio-oil under atmospheric conditions. This novel transformation process included the catalytic cracking of bio-oil to light olefins and the subsequent synthesis of liquid hydrocarbon bio-fuels from light olefins with two reactors in series. The yield of bio-fuel was up to 193.8 g/(kg bio-oil) along with a very low oxygen content, high RONs (research octane numbers), high LHVs (lower heating values) and low benzene content under the optimizing reaction conditions. Coke deposition seems to be the main cause of catalyst deactivation in view of the fact that the deactivated catalysts was almost recovered by on-line treating the used catalyst with oxygen. The integrated transformation potentially provides a useful way for the development of gasoline range hydrocarbon fuels using renewable lignocellulose biomass.

The continual growth in commercial aviation fuels and more strict environmental legislations have led to immense interest in developing green aviation fuels from renewable lignocellulosic biomass. This work demonstrated a novel transformation of biomass into bio-jet and diesel fuels. The transformation included following three reaction steps: (i) the catalytic pyrolysis of sawdust into low-carbon aromatics, (ii) the production of C8–C15 aromatics by the aromatic alkylation and (iii) the production of C8–C15 cyclic alkanes by the hydrogenation of C8–C15 aromatics. The production of the desired C8–C15 aromatics with the highest selectivity of 92.4% was achieved by the low temperature alkylation reactions of the low carbon aromatics using the ionic liquid of [bmim]Cl–2AlCl 3 (1-butyl-3-methylimidazolium chloroaluminate). The biofuels derived from sawdust basically met the main specifications of jet fuels. This transformation potentially provides a useful avenue for the development of green aviation biofuels utilizing lignocellulose biomass.

The growing demand of commercial jet fuels, in combination with the strict environmental legislations, has led to immense interest in developing aviation biofuels. This work demonstrated that the bio-oil derived from fast pyrolysis of straw stalk was able to be converted into the jet and diesel fuel range hydrocarbons by a designed transformation route. This transformation included three reaction steps: (i) the catalytic cracking of bio-oil into low-carbon aromatics and light olefins, (ii) the synthesis of C8-C15 aromatic hydrocarbons by the alkylation of low-carbon aromatics with light olefins, and (iii) the production of C8-C15 cyclic alkanes by the hydrogenation of C8-C15 aromatics. It was also demonstrated that the production of the desired C8-C15 aromatics with a high selectivity of 88.4% was achieved by the low temperature alkylation reactions of the bio-oil-derived aromatics using the ionic liquid of [bmim]Cl-2AlCl(3) (1-butyl-3-methylimidazolium chloroaluminate). The synthetic biofuels basically met the main technical specifications of jet fuels based on the combustion heat, viscosity, freeze point and other characteristics of fuels. (C) 2015 Elsevier Ltd. All rights reserved.

The continual growth in commercial aviation fuels and more strict environmental legislations have led to immense interest in developing green aviation fuels from biomass. This paper demonstrated a controllable transformation of lignin into jet and diesel fuel range hydrocarbons, involving directional production of C8-C15 aromatics by the catalytic depolymerization of lignin into C6-C8 low carbon aromatic monomers coupled with the alkylation of aromatics, and the directional production of C8-C15 cycloparaffins by the hydrogenation of aromatics. The key step, the production of the desired C8-C15 aromatics with the selectivity up to 94.3%, was achieved by the low temperature alkylation reactions of the lignin-derived monomers using ionic liquid. The synthetic biofuels basically met the main technical requirements of conventional jet fuels. The transformation potentially provides a useful way for the development of cycloparaffinic and aromatic components in jet fuels using renewable lignocellulose biomass.

Background G protein-coupled receptors (GPCRs) participate in a variety of physiologic functions, and several GPCRs have critical physiologic and pathophysiologic roles in the regulation of renal function. We investigated the role of Gpr97, a newly identified member of the adhesion GPCR family, in AKI. Methods AKI was induced by ischemia–reperfusion or cisplatin treatment in Gpr97-deficient mice. We assessed renal injury in these models and in patients with acute tubular necrosis by histologic examination, and we conducted microarray analysis and in vitro assays to determine the molecular mechanisms of Gpr97 function. Results Gpr97 was upregulated in the kidneys from mice with AKI and patients with biopsy-proven acute tubular necrosis compared with healthy controls. In AKI models, Gpr97-deficient mice had significantly less renal injury and inflammation than wild-type mice. Gpr97 deficiency also attenuated the AKI-induced expression of semaphorin 3A (Sema3A), a potential early diagnostic biomarker of renal injury. In NRK-52E cells subjected to oxygen–glucose deprivation, siRNA-mediated knockdown of Gpr97 further increased the expression of survivin and phosphorylated STAT3 and reduced toll-like receptor 4 expression. Cotreatment with recombinant murine Sema3A protein counteracted these effects. Finally, additional in vivo and in vitro studies, including electrophoretic mobility shift assays and luciferase reporter assays, showed that Gpr97 deficiency attenuates ischemia–reperfusion-induced expression of the RNA-binding protein human antigen R, which post-transcriptionally regulates Sema3A expression. Conclusions Gpr97 is an important mediator of AKI, and pharmacologic targeting of Gpr97-mediated Sema3A signaling at multiple levels may provide a novel approach for the treatment of AKI.

Despite substantial progress being made in understanding the mechanisms contributing to the pathogenesis of renal fibrosis, there are only a few therapies available to treat or prevent renal fibrosis in clinical use today. Therefore, identifying the key cellular and molecular mediators involved in the pathogenesis of renal fibrosis will provide new therapeutic strategy for treating patients with chronic kidney disease (CKD). β-Arrestin-1, a member of β-arrestin family, not only is a negative adaptor of G protein-coupled receptors (GPCRs), but also acts as a scaffold protein and regulates a diverse array of cellular functions independent of GPCR activation. In this study, we identified for the first time that β-arrestin-1 was upregulated in the kidney from mice with unilateral ureteral obstruction nephropathy as well as in the paraffin-embedded sections of human kidneys from the patients with diabetic nephropathy, polycystic kidney, or uronephrosis, which normally causes renal fibrosis. Deficiency of β-arrestin-1 in mice significantly alleviated renal fibrosis by the regulation of inflammatory responses, kidney fibroblast activation, and epithelial-mesenchymal transition (EMT) in both in vivo and in vitro studies. Furthermore, we found that among the major isoforms of Wnts, Wnt1 was regulated by β-arrestin-1 and gene silencing of Wnt1 inhibited the activation of β-catenin and suppressed β-arrestin-1-mediated renal fibrosis. Collectively, our results indicate that β-arrestin-1 is one of the critical components of signal transduction pathways in the development of renal fibrosis. Modulation of these pathways may be an innovative therapeutic strategy for treating patients with renal fibrosis.β-Arrestin-1 was upregulated in the kidney from mice with UUO nephropathy. β-Arrestin-1 regulated kidney fibroblast activation and epithelial-mesenchymal transition. β-Arrestin-1 exacerbated renal fibrosis via mediating Wnt1/β-catenin signaling.

We present an analysis of lightning electromagnetic fields taking into account the soil stratification and frequency dependence of its electrical parameters. Two current waveforms corresponding to typical first and subsequent return strokes are considered for the analysis. Different cases for the soil (homogeneous, 2-layer, frequency-dependent/constant electrical parameters) are considered. The analysis is carried out considering different distance ranges: close (50 m), intermediate (5 km) and distant (100 km). The obtained results confirm that the vertical electric field and the azimuthal magnetic field at close range can be evaluated assuming the ground as a perfectly conducting plane. The impact of the soil stratification and frequency-dependent parameters on the vertical electric field and azimuthal magnetic field appear at intermediate and distant ranges. On the other hand, the horizontal electric field is found to be very sensitive to the ground stratification for all the considered distance ranges. However, at close range, the impact of the soil becomes less significant for observation points that are located at above-ground heights of 10 m or higher. It is shown that the three field components are affected more markedly by the soil stratification than by the frequency dependence of its electrical parameters, especially for intermediate and distant ranges (i.e., 5 km and 100 km). Furthermore, subsequent return stroke fields are more significantly affected by the soil stratification and frequency-dependence compared to first return stroke fields. The impact of the frequency-dependent soil parameters on the considered field components is more noticeable in a poorly conducting soil compared to a good conducting soil. We present also a comparison between simulation results with simultaneous measurements of current and distant vertical electric fields associated with rocket-triggered lightning flashes. It is shown that the computed vertical electric field waveforms for the case of a two-layer soil follow to a much better extent the corresponding experimental waveforms compared a non-stratified ground model. The frequency-dependence of the soil affects slightly the early-time response of the field. However, the late-time response of the field is essentially determined by the soil stratification.

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.

Efficient production of clean biofuels using CO2-rich bio-oil-based syngas obtained from bio-oil steam reforming was performed over a Fe1.5Cu1Zn1Al1K0.117 catalyst. The effects of synthesis parameters (temperature, pressure, gas hourly space velocity) on the performance of the biofuel synthesis were investigated. The maximum biofuel yield reaches about 0.63 kg biofuels/(kgcata·h) with a contribution of 0.40 kg alcohols/(kgcata·h) and 0.23 kg liquid hydrocarbons/(kgcata·h). The content of C2+ alcohols (mainly C2–C6 alcohols) in the alcohols products is 87.04–91.15 wt%. Some important elementary steps involved in the biofuel synthesis, including the reverse water-gas shift reaction and methanation, were also investigated in detail.

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.

The gas in the coal seam is an important disaster-causing factor that affects and restricts the safe and efficient mining in coal mines. The use of directional drilling in the coal seam is the preferred method to reduce the gas content and pressure of the coal seam. In the past two decades, the directional drilling technology and equipment have been widely used in high-gas coal mine in China, and remarkable gas control effects have been achieved. In view of the need for gas control in super-long working face in China, it is proposed to use ZDY12000LD directional drill rig, BLY460/13 pump, survey system and supporting drilling tools to carry out directional drilling of in-seam over 2,000m, and to summarize and form the matching technology of directional drilling over 2,000m. It provides a new way to improve the construction capability of directional borehole in coal mines and explore a new mode for gas control in long working face.

Transformation of lignin to ethylbenzene can provide an important bulk raw material for the petrochemical industry. This work explored the production of ethylbenzene from lignin through the directional catalytic depolymerization of lignin into the aromatic monomers followed by the selective alkylation of the aromatic monomers. For the first step, the aromatics selectivity of benzene derived from the catalytic depolymerization of lignin reached about 90.2 C-mol% over the composite catalyst of Re-Y/HZSM-5 (25). For the alkylation of the aromatic monomers in the second step, the highest selectivity of ethylbenzene was about 72.3 C-mol% over the HZSM-5 (25) catalyst. The reaction pathway for the transformation of lignin to ethylbenzene was also addressed. Present transformation potentially provides a useful approach for the production of the basic petrochemical material and development of high-end chemicals utilizing lignin as the abundant natural aromatic resource.

BACKGROUND Catalytic transformation of bio-oil into higher olefins can provide valuable bio-fuels and chemicals used in the manufacture of high-octane gasoline, detergents, plasticizers and other petrochemicals. This work explores the production of higher olefins from bio-oil through catalytic cracking of bio-oil along with light olefins oligomerization. RESULTS For bio-oil catalytic cracking, the olefins yield reached 43.8 C-mol% with near-complete bio-oil conversion. The oxygenated organic compounds in bio-oil go through deoxygenation, cracking and hydrogen transfer reactions and form light olefins over the zeolite acid sites. For the oligomerization of light olefins, the highest selectivity and yield of C5+ olefins over the LTGO catalyst reached 85.4 C-mol% and 326.7 g kg−1cata h−1, respectively. Main products below 300°C were C6=—C12= olefins, originating from light olefin oligomerization. The influences of the reaction conditions were investigated in detail, and the reaction mechanism was addressed. CONCLUSION Bio-oil can be catalytically converted to C2=–C4= light olefins over HZSM-5, and further selectively transformed to C5+ high olefins via the oligomerization of light olefins over LTGO. The transformation of bio-oil to higher olefins may be useful for the production of bio-fuels and high value chemicals using renewable biomass. © 2013 Society of Chemical Industry

Biomass conversion into benzene, toluene and xylenes (BTX) can provide basic feedstocks for the petrochemical industry, which also serve as the most important aromatic platform molecules for development of high-end chemicals. Present work explored a new route for transformation of bio-oil tar into BTX through current-enhanced catalytic conversion (CECC), involving the synergistic effect between the zeolite catalyst and current to promote the deoxygenation and cracking reactions. The proposed transformation shows an excellent BTX aromatics selectivity of 92.9 C-mol% with 25.1 wt.% yield at 400 °C over usual HZSM-5 catalyst. The study of the model compounds revealed that the groups such as methoxy, hydroxyl and methyl in aromatics can be effectively removed in the CECC process. Present transformation potentially provides an important approach for production of the key petrochemicals of BTX and the overall use of bio-oil tar derived from bio-oil or biomass.

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 rice husk, sawdust, sugarcane bagasse, cellulose, hemicellulose and lignin into olefins was performed with HZSM-5 containing 6 wt.% lanthanum. The olefins yields for different feedstocks decreased in the order: cellulose > hemicellulose > sugarcane bagasse > rice husk > sawdust > lignin. Biomass containing higher content of cellulose or hemicellulose produced more olefins than feedstocks with higher content of lignin. Among the biomass types, sugarcane bagasse provided the highest olefin yield of 0.12 kg olefins/(kg dry biomass) and carbon yield of 21.2 C-mol%. Temperature, residence time and the catalyst/feed ratio influenced olefin yield and selectivity. While the HZSM-5 zeolite was catalytically active, the incorporation of lanthanum at 2.9, and 6.0 wt.% increased the production of olefins from rice husk by 15.6% and 26.5%, respectively. The conversion of biomass to light olefins potentially provides an alternative and sustainable route for production of the key petrochemicals.

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.

The NOx storage features and mechanism of a K-doped [Ca24Al28O64]4+·4O– catalyst (designated as C12A7-O–/K) were systematically investigated. The NOx storage capability (NSC) of the C12A7-O–/K catalyst was found to depend primarily on the temperature, the K-doping level, and the oxygen concentration in the gas mixture. The C12A7-O–/10%K catalyst exhibited the highest storage capacity among the C12A7-O–/M (M = K, Na, Mg) catalysts investigated, attaining a maximum NSC value of 183.9 μmol/g at about 550 °C. The optimum temperature window for NOx storage with C12A7-O–/10%K catalyst ranged from 400 to 650 °C. Thermogravimetric analysis (TGA), X-ray diffraction (XRD), and Fourier transform infrared (FT-IR) spectroscopy were utilized to identify the catalyst characteristics and the active species, both in the body of the catalyst and on its surface. Additionally, anionic time-of-flight mass spectrometry (TOF-MS) measurements were employed to investigate the anionic intermediates desorbed from the catalyst surfa...

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 (

A novel approach for high efficient conversion of the CO(2)-rich bio-syngas into the CO-rich bio-syngas was carried out by using biomass char and Ni/Al(2)O(3) catalyst, which was successfully applied for production of bio-methanol from bio-oil. After the bio-syngas conditioning, the CO(2)/CO ratio prominently dropped from 6.33 to 0.01-0.28. The maximum CO yield in the bio-syngas conditioning process reached about 1.96 mol/(mol CO(2)) with a nearly complete conversion of CO(2) (99.5%). The performance of bio-methanol synthesis was significantly improved via the conditioned bio-syngas, giving a maximum methanol yield of 1.32 kg/(kg(catalyst)h) with a methanol selectivity of 99%. Main reaction paths involved in the bio-syngas conditioning process have been investigated in detail by using different model mixture gases and different carbon sources.

Ab initio and Rice–Ramsperger–Kassel–Marcus theories are carried out to study the potential energy surface and the energy-dependent rate constants and branching ratios of the products for O(1D) + CH3CHF2 reaction. Optimized geometries and vibrational frequencies have been obtained by MP2/6-311G(d,p) method. The main products of the title reaction are CH3CFO + HF, CH2CFOH + HF, and CH3 + CF2OH at lower collision energy; and CH3 + CF2OH, CH3CF2 + OH are the main products at higher collision energy. CHF2 + CH2OH are the main products in the whole range of collision energy. © 2011 Wiley Periodicals, Inc. Int J Quantum Chem, 2012

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 potential energy surface of O(1D) + CH3CH2Br reaction has been studied using QCISD(T)/6-311++G(d,p)//MP2/6-311G(d,p) method. The calculations reveal an insertion-elimination reaction mechanism of the title reaction. The insertion process has two possibilities: one is the O(1D) inserting into CBr bond of CH3CH2Br producing one energy-rich intermediate CH3CH2OBr and another is the O(1D) inserting into one of the CH bonds of CH3CH2Br producing two energy-rich intermediates, IM1 and IM2. The three intermediates subsequently decompose to various products. The calculations of the branching ratios of various products formed though the three intermediates have been carried out using RRKM theory at the collision energies of 0, 5, 10, 15, 20, 25, and 30 kcal/mol. CH3CH2O + Br are the main decomposition products of CH3CH2OBr. CH3COH + HBr and CH2CHOH + HBr are the main decomposition products for IM1; CH2CHOH + HBr are the main decomposition products for IM2. As IM1 is more stable and more likely to form than CH3CH2OBr and IM2, CH3COH + HBr and CH2CHOH + HBr are probably the main products of the O(1D) + CH3CH2Br reaction. Our computational results can give insight into reaction mechanism and provide probable explanations for future experiments. © 2009 Wiley Periodicals, Inc. Int J Quantum Chem, 2011

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.

High efficient production of hydrogen from the crude bio-oil was performed in the gasification-reforming dual beds. A recently developed electrochemical catalytic reforming method was applied in the downstream reforming bed using NiCuZnAl catalyst. Production of hydrogen from the crude bio-oil through both the single gasification and integrative gasification-reforming processes was investigated. The maximum hydrogen yield of 81.4% with carbon conversion of 87.6% was obtained through the integrative process. Hydrogen is a major product (∼73 vol%) together with by-products of CO2 (∼26 vol%) as well as very low content of CO (

Present study reports on high catalytic activity of CNTs-supported Ni catalyst (x% Ni-CNTs) synthesized by the homogeneous deposition–precipitation method, which was successfully applied for low-temperature reforming of organic compounds in bio-oil. The optimal Ni-loading content was about 15 wt%. The H2 yield over the 15 wt% Ni-CNTs catalyst reached about 92.5% at 550 °C. The influences of the reforming temperature (T), the molar ratio of steam to carbon fed (S/C) and the current (I) passing through the catalyst, on the reforming process of the bio-oil over the Ni-CNTs' catalysts were investigated using the stream as the carrier gas in the reforming reactor. The features of the Ni-CNTs' catalysts with different loading contents of Ni were investigated via XRD, XPS, TEM, ICP/AES, H2-TPD and the N2 adsorption–desorption isotherms. From these analyses, it was found that the uniform and narrow distribution with smaller Ni particle size as well as higher Ni dispersion was realized for the CNTs-supported Ni catalyst, leading to excellent low-temperature reforming of oxygenated organic compounds in bio-oil.

The potential energy surface of O( 1 D) + CH 3 CH 2 F reaction has been studied using QCISD(T)/6-311++G(d,p)//MP2/6-311G(d,p) method. The calculations reveal an insertion–elimination reaction mechanism of the title reaction. The insertion process has two possibilities: one is the O( 1 D) atom inserting into C–F bond of CH 3 CH 2 F produces one energy-rich intermediate CH 3 CH 2 OF and another is the O( 1 D) atom inserting into one of the C–H bonds of CH 3 CH 2 F produces two energy-rich intermediates, IM1 and IM2. The three intermediates subsequently decompose to various products. The calculations of the branching ratios of various products formed though the three intermediates have been carried out using RRKM theory at the collision energies of 0, 5, 10, 15, 20, 25 and 30 kcal/mol. CH 3 CH 2 O is the main decomposition product of CH 3 CH 2 OF. HF and CH 3 are the main decomposition products for IM1; CH 2 OH is the main decomposition product for IM2. Since IM1 is more stable and more likely to form than CH 3 CH 2 OF and IM2, HF and CH 3 are probably the main products of the O( 1 D) + CH 3 CH 2 F reaction. Our computational results can give insight to reaction mechanism and provide probable explanations for future experiments.

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.

Production of hydrogen from ethanol with high hydrogen yield and high energy efficiency was performed by using an electrochemical catalytic reforming (ECR) approach over the Ni-based catalyst. ECR was carried out in the fixed-bed continuous flow reactor, where an ac electronic current passed through the catalyst. It was found that the performance of the ethanol reforming not only depended on the reforming temperature, but also was remarkably enhanced by the current through the catalyst. In particular, the hydrogen yield and its selectivity significantly increased with an increase in the current in ECR. The promoting effects of the current on the decomposition of ethanol were also studied via the homogeneous experiments and low-pressure time-of-flight measurements. The alteration of the catalyst after the ECR processes was investigated via X-ray diffraction, transmission electron microscopy, and Brunauer−Emmett−Teller measurements. The mechanism of the electrochemical catalytic reforming of ethanol was dis...

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.

Production of hydrogen from acetic acid (HAc) was performed by using a novel electrochemical catalytic reforming (ECR) approach over the 18%NiO/Al 2 O 3 catalyst. ECR was carried out in a fixed-bed continuous flow reactor, where an ac electric current was passed through the catalyst. A high yield of hydrogen (>90%) and carbon conversion (>90%) were obtained as the reforming temperature over 400 °C via the ECR approach. The influences of the current on the HAc decomposition, its reforming, and the catalyst reduction in the ECR process have been investigated, which were compared with those in the common steam reforming (CSR) route. The mechanism of the HAc reforming in ECR was also discussed based on the present investigation.

High-efficient production of hydrogen from bio-oil was performed by a novel electrochemical catalytic reforming method over the NiCuZn–Al2O3 catalyst. The influences 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 nearly complete conversion with a hydrogen yield of 93.5% even at low reforming temperature of 400 °C. The thermal electrons would play important roles in promoting the reforming reactions of the oxygenated-organic compounds in bio-oil, molecular dissociation and the catalyst reduction.

Atomic fluorine anion (F−) emission from the nanoporous crystal [Ca24Al28O64]4+·(F−)3.36(O2−)0.32 (C12A7-F−) surface, was observed via a time-of-flight mass spectrometry (TOF-MS). C12A7-F− is a nan...

The present study provides a novel approach to produce pure and stable atomic fluorine anions (F−) in the gas phase by using the F− storage emission material of [Ca24Al28O64]4+·(O2−)0.35(F−)3.30 (abbreviated as C12A7-F−), synthesized by the solid-state reaction of CaF2, CaCO3, and γ-Al2O3. The anionic species stored in the C12A7-F− material were dominated by the F− anions, about (1.9 ± 0.3) × 1021 cm−3, accompanied by a small amount of O2−, O−, and O2−, via ion chromatography and electron paramagnetic resonance measurements, which corroborates that the anionic species emitted from the C12A7-F− surface were dominated by the F− anions (about 90%) together with a small amount of the O− anions and electrons, identified by a time-of-flight mass spectroscopy. The absolute emission current density of F− was sensitive to the surface temperature and extraction field, reaching about 16.7 ± 0.8 µA/cm2 at 800 °C and 1200 V/cm. A pure and stable atomic fluorine anion beam was developed by using an electrochemistry imp...

A novel approach to surface modification of polystyrene (PS) polymer with atomic oxygen radical anions-dissolved solution (named as O − water) has been investigated. The O − water, generated by bubbling of the O − (atomic oxygen radical anion) flux into the deionized water, was characterized by UV-absorption spectroscopy and electron paramagnetic resonance (EPR) spectroscopy. The O − water treatments caused an obvious increase of the surface hydrophilicity, surface energy, surface roughness and also caused an alteration of the surface chemical composition for PS surfaces, which were indicated by the variety of contact angle and material characterization by atomic force microscope (AFM) imaging, field emission scanning electron microscopy (FESEM), X-ray photoelectron spectroscopy (XPS), and attenuated total-reflection Fourier transform infrared (ATR-FTIR) measurements. Particularly, it was found that some hydrophilic groups such as hydroxyl (OH) and carbonyl (C O) groups were introduced onto the polystyrene surfaces via the O − water treatment, leading to the increases of surface hydrophilicity and surface energy. The active oxygen species would react with the aromatic ring molecules on the PS surfaces and decompose the aromatic compounds to produce hydrophilic hydroxyl and carbonyl compounds. In addition, the O − water is also considered as a “clean solution” without adding any toxic chemicals and it is easy to be handled at room temperature. Present method may suit to the surface modification of polymers and other heat-sensitive materials potentially.

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.