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Upgrading pyrolysis oil by hydrodeoxygenation (HDO) is a promising route for the production of advanced biofuels. The proper reaction conditions and catalysts are important for the success of this process. Previously our research group investigated the ratio of Zn and Pd on the synergistic effect for HDO bio-oil upgrading. This present research focuses on determining the optimal reaction conditions for HDO conversion of pyrolysis oil produced from pine sawdust. Temperatures of 150, 200 and 250 °C and hydrogen pressures of 1.38, 2.76 and 4.14 MPa were evaluated. Syngas, liquids and coke were the primary products evaluated. Syngas was characterized using a Gas chromatography (GC). The liquids were characterized using a Gas chromatography–mass spectrometry (GC–MS). Increasing reaction temperature resulted in increased coke yields. Treatment at 250 °C and 1.38 MPa resulted in the highest hydrocarbon content (6.06%). The treatment at 200 °C and 1.38 MPa produced the largest amounts of hydrocarbons in C6–C12 range (5.07%). The physicochemical characterizations further support the GCMS results. Syngas analysis revealed that higher hydrogen pressure leads to increased hydrogen consumption and results in more oxy-compounds conversion to hydrocarbons. The syngas analysis also supports the liquid analysis result.

Cracking of camelina oil over non-catalyst and ZSM-5 catalyst doped with different Zn concentrations (0, 10, 20 and 30 wt.%) in a fixed-bed reactor was investigated. The fresh and used catalysts were characterized using XRD, FT-IR, BET and TEM. Characterizations of the produced hydrocarbon biofuel, distillation residual and non-condensable gas were carried out. The effect of non-catalyst and catalyst on the physicochemical properties and yield of products was discussed. The results showed that the introduction of Zn did not change the zeolite crystalline structure and ZnO might deposit on the external surface and/or inside the pores of the support ZSM-5. After upgrading, hydrocarbon biofuel had a lower viscosity, lower density, higher heating value (HHV) and higher water content than raw camelina oil. The optimum Zn concentration to ZSM-5 was 20 wt.%, at which the highest hydrocarbon biofuel yield and comprehensively the best quality were obtained. Compared to non-catalytic cracking of camelina oil, the loading of Zn to ZSM-5 could improve some physicochemical properties of the hydrocarbon biofuel. In addition, the loading of Zn to ZSM-5 could facilitate the chemical reactions such as decarbonylation and dehydrogenation.

A novel Heck reaction catalyst consisting of a palladium(II) complex of meso-tetra(p-hydroxyphenyl)porphyrin (MTP) and cross-linked chloromethylated polystyrene microspheres (PMs) was successfully prepared via covalent ether bonds between the chloride groups in the PMs and the hydroxyl groups in MTP. The catalyst was characterized using scanning electron microscopy, Fourier-transform infrared spectroscopy, and inductively coupled plasma atomic emission spectroscopy (ICP-AES). This polystyrene-supported palladium-complex was an efficient heterogeneous catalyst for cross-coupling of aryl iodides with ethyl acrylate. The reaction of iodobenzene and ethyl acrylate under N-2 at 100 degrees C and a catalyst concentration of 0.1% gave a gas chromatography product yield of 99.8%, which is much higher than that achieved using a free palladium(II) complex of MTP as the catalyst (41.3%). The catalyst was recycled up to six times without significant loss of catalytic activity. These results suggest that the immobilized palladium(II)-MTP catalyst has potential applications in synthetic and industrial chemistry. (C) 2014 Chinese Society of Particuology and Institute of Process Engineering, Chinese Academy of Sciences. Published by Elsevier B.V. All rights reserved.

Mo–Cu/HZSM-5 catalysts for pine sawdust thermal conversion were prepared using an impregnation method. The Mo–Cu/HZSM-5 catalysts and HZSM-5 were characterized by Brunauer–Emmett–Teller (BET), X-ray diffraction (XRD) and transmission electron microscopy (TEM). All characterization results indicated that the introduction of CuO is beneficial to the dispersion of MoO3 in the HZSM-5. Combined with the two-stage catalytic pyrolysis system, the Mo–Cu/HZSM-5 catalysts were used for pine sawdust thermal conversion. The products included gas, bio-oil and bio-char. The gas was analyzed by Gas chromatography (GC). Gas chromatography–mass spectrometry (GC–MS) was used to identify the compounds in bio-oils. The water content, higher heating value (HHV) and viscosity of bio-oils were measured. The HHV and elements of bio-char were determined. The results indicated that Mo(3%)–Cu(3%)/HZSM-5 treatment yielded the highest amount of C6–C12 hydrocarbons, showed a robust ability to convert methane in the gas to bio-oil, and displayed no significant difference in the properties of bio-char when compared to different treatments in the same pyrolysis conditions.

In this study, the pine sawdust thermal conversions over HZSM-5 catalyst were carried out under different reaction temperatures in a two-stage catalytic pyrolysis reactor. Higher temperatures in the catalytic reactor tended to decrease the yield of bio-oil and change the component of bio-oil. The results from the gas chromatography–mass spectrometry (GC–MS) analysis showed that the pyrolysis reaction at 500 °C and catalytic reaction at 500 °C treatment obtained the highest hydrocarbon content (58.63%) and the highest C 8 –C 12 content (48.03%) in the oil phase of the bio-oil. The X-ray diffraction (XRD) and selected-area-electron-diffraction (SEAD) characterization showed that the distortion of the ZSM-5 zeolite lattice occurred before and after use. The Brunauer–Emmett–Teller (BET) characterization indicated that the formation of coke increased as the catalytic temperature rose. The physical characterization of bio-oils, such as water content, density, viscosity, pH, and higher heating value (HHV) further demonstrated that HZSM-5 catalyst was beneficial in achieving low viscosity and higher HHV bio-oils. All the results suggest that the two-stage catalytic pyrolysis reactor with HZSM-5 catalyst has a great potential for achieving advanced biofuel.

Polyethylenimine-grafted poly(glycidyl methacrylate) (PGMA-PEI) microspheres were prepared using the dispersion polymerization method and a two-step reaction with ethylenediamine (EDA) and polyethylenimine (PEI). The PGMA-PEI microspheres were then characterized by Fourier transform infrared spectroscopy (FTIR) and scanning electron microscopy (SEM) and tested for their ability to remove hexavalent chromium (Cr(VI)) from an aqueous solution in batch tests. The results demonstrated that Cr(VI) adsorption depended significantly on pH. The optimized pH value for the Cr(VI) adsorption was 2.0. The adsorption isotherms of PGMA-PEI microspheres with Cr(VI) fit the Langmuir model. The maximum adsorption capacities were 460.83, 485.44 and 505.05 mg g(-1) for PGMA-PEI600, PGMA-PEI1800 and PGMA-PEI10,(172) microspheres, respectively. The adsorption reached equilibrium within 10min and the experimental data fit the pseudo-second-order model. The obtained thermodynamic parameters (Delta G(0), Delta H-0 and Delta S-0) showed that the adsorption of Cr(VI) was an endothermic and spontaneous process. Competition from coexisting ions of K+, Na+, Ca2+, Cu2+, Cl-, NO3-, H2PO4-, and HPO42- was insignificant except SO42-. The regeneration study revealed that PGMA-PEI microspheres could be repeatedly used with no significant loss of adsorption efficiency. (C) 2014 Elsevier B.V. All rights reserved.

Bio-jet fuel produced from non-edible oilseeds can be an alternative to fossil fuels with the benefits of increasing national energy security, reducing environmental impact, and fostering rural economic growth. Efficient oil extraction from oilseeds is critical for economic production of bio-jet fuels. Oil extractions from camelina (sativa) and canola (Brassica napus) seeds were conducted using a cold press method. The effect of the frequency controlling the screw rotation speed on the oil recovery and quality was discussed. Characterization of the produced raw vegetable oils, such as heating value, elemental content and main chemical compositions, was carried out. The results showed that the oil recovery increased when the frequency decreased. The highest oil recoveries for camelina and canola seeds were 88.2% and 84.1% respectively, both at 15 Hz. The cold press frequency and processing temperature (97.2°C - 106.0°C) had a minor influence on the qualities and recovery of both camelina and canola oils. In addition, camelina and canola oils produced at 15 Hz underwent catalytic cracking to examine potential hydrocarbon fuels production. It was observed that some of oil physicochemical properties were improved after catalytic cracking. Although more study is needed for further improvement of oil recovery and qualities, cold press could be an efficient method for oil extraction from non-edible oilseeds. Additionally, the preliminary results of upgrading the oils produced show very promising for future bio-jet fuels production.

Micron-sized polyethylenimine-functionalized poly(glycidyl methacrylate) superparamagnetic microspheres (m-PGMA-PEI) were prepared by a process involving: (1) synthesis of PGMA microspheres using the dispersion polymerization method; (2) ring-opening reaction of epoxy groups on PGMA microspheres with ethylenediamine (EDA) to yield amino groups; (3) in situ coprecipitation of Fe3O4 nanoparticles into the pores of microspheres; (4) Michael addition of amino groups with methyl acrylate (MA) to yield ester groups; and (5) amidation of the terminal ester groups with polyethylenimine (PEI). Once generated, the resulting m-PGMA-PEI microspheres were tested for their ability to remove Cr(VI) from an aqueous solution in batch experiments. The results demonstrated that Cr(VI) adsorption was significantly pH dependent. The optimized pH value was 2.0. The adsorption isotherm of the adsorbent fit the Langmuir model, with the maximum adsorption capacity of 492.61 mg/g. The Cr(VI) adsorption rate was rapid, and the adsorption reached equilibrium within 15 min. The thermodynamic parameters (Delta G(0), Delta H-0, Delta S-0) demonstrated that the adsorption process was endothermic and spontaneous in nature. The presence of the coexisting anions involving Cl-, NO3-, H2PO4- and HPO42- had no remarkable influence on Cr(VI) adsorption except SO42-. The regeneration study proved that the m-PGMA-PEI microspheres could be repeatedly utilized with no significant loss of adsorption efficiency. (C) 2013 Elsevier B.V. All rights reserved.

A novel separation technology at room temperature for traditional Chinese medicines was proposed in this work by adding magnetic molecularly imprinted polymers (M-MIPs) into extraction solution and sample matrix. The M-MIPs show a more adsorption capacities and higher selectivity for the template than magnetic non-molecularly imprinted polymers (M-NMIPs) without the specific binding sites. Addition of the M-MIPs to the extraction solution provides one-step extraction and cleanup, the improvement of extraction rate and extraction yields of three tanshinones (from 0.40, 0.23 and 0.12 mg g(-1) in 240 min by solvent extraction to 0.52, 0.27 and 0.19 mg g(-1) in 5 min by 200 mg sorbent), and reusability of extraction solvent. The extraction yields of three tanshinones by this technology at room temperature in 5 min were higher than those by ultrasonic extraction in 30 min, by heat reflux extraction in 45 min and by solvent extraction at room temperature in 4 h. The integrated technology has the advantages of one-step extraction and cleanup, high extraction efficiency, low solvent consumption and room temperature. Crown Copyright (C) 2013 Published by Elsevier B.V. All rights reserved.

Catalytic fast pyrolysis (CFP) is proven one of the most promising processes for effectively converting biomass to liquid advanced biofuels. The yield and quality of biofuels are depended on biomass species, reactor type, operating conditions (such as temperature, pressure, heating rate, etc.) as well as the presenting of appropriate catalysts. Based on current CFP research, a hypothesis of biomass precision pyrolysis was proposed. A novel accurate control catalyst fast pyrolysis (ACCFP) reactor was invented and tested for exploration of biomass precision pyrolysis possibility. Various lignocellulosic biomass materials such as switchgrass, corn stover, prairie cordgrass, and pine sawdust were tested. The effects of reaction temperature, pressure, and heating rate on pyrolysis products (bio-oil, bio-char, and biosyngas) were investigated. ZSM-5 combined with various metal catalysts were applied in the ACCFP process. The pyrolysis products (bio-oil, bio-char, and biosyngas) produced were characterized for their physicochemical properties such as total acid number (TAN), water content, density, pH value, viscosity, higher heating value, and/or chemical composition. The results indicated that it is possible to accurately control CFP processing conditions to produce target bioproducts, which may lead to biomass precision pyrolysis. Compared to conventional pyrolysis, the ACCFP process could improve pyrolysis products yields and quality, such as greatly reducing oxygen content in the bio-oils produced. Although further research is needed, the study confirms that precision biomass pyrolysis may be an effective pathway for converting lignocellulosic biomass to advanced biofuels or chemicals.

Because not conflict with human and animal food resources, non-food vegetable oils are promising sources for developing liquid advanced biofuel. Directly upgrading non-food vegetable oils to hydrocarbon fuels is likely offering reasonable profit margin for bio-jet fuel production. The sunflower oil extracted from residues that were produced in sunflower seed de-hulled processing is inedible due to its quality not meeting food standards. Genetically modified sunflower grown on margin lands can also provide one possible non-food source for sustainable biofuel production source since it doesn’t compete with the use of arable lands. Sunflower oils produced from those non-food sources were cracked on ZSM-5 catalysts in a fixed-bed reactor at three temperatures, 450 °C, 500 °C, and 550 °C. Characterization of the upgraded sunflower oils, advanced hydrocarbon fuel and distilled residual fuel, including pH value, density, water content, viscosity, heating value, and fatty acid profile, was carried out. The composition of non-condensable gases generated during the catalytic cracking process was also analyzed. The effect of the reaction temperatures on the upgraded sunflower oils’ yield and quality was discussed. The results showed that reaction temperatures affected the yield and properties of upgraded sunflower oils. The highest yield of advanced hydrocarbon fuel from raw sunflower oils was 21.1% at 550 °C. Upgraded sunflower oils were a mixture of un-cracked oils and hydrocarbons. After distillation, the advanced hydrocarbon fuel had lower viscosity, moisture content and density. The non-condensable gases contained C 1 – C 5 light hydrocarbons, H 2 , CO, CO 2 , etc. The reaction temperatures had significant effect on the concentrations of these compounds during catalytically cracking sunflower oils.

Bio-jet fuel produced from non-food oilseeds can be an alternative to fossil fuels with the benefits of increasing national energy security, less impact on environment, and fostering rural economic growth. Efficient oil extraction from oilseeds is critical for the production of bio-jet fuels. In this study, oil extractions from camelina and canola (Brassica napus) seeds were conducted using a cold press method. The effect of the frequency controlling the screw rotating speed on the oil yield and quality was discussed. Characterization of the produced raw vegetable oils, including pH value, density, water content, viscosity, heating value, element component, and fatty acid profile, was carried out. The remaining oil contents left in the cold press meals were also determined. The results show that the oil recovery increased when the frequency decreased. The highest oil recoveries for camelina and canola seeds were 88.2% and 84.1% respectively, both at 15 HZ. The cold press frequency and processing temperature (97.2 °C - 106.0 °C) had minor influence on the quality and yield of both camelina and canola oils. In addition, camelina oil produced at 15 HZ was catalytically cracked to examine the potential of upgrading to hydrocarbon fuels. It was observed that some of oil physicochemical properties were improved after catalytic cracking. Though more study is needed for further improvement of oil recovery and quality, cold press could be an efficient method for oil extraction from non-food oilseeds and the oil produced is promising for future bio-jet fuel production.