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The steam gasification of tableted biomass for H2 production in molten salts was investigated under different conditions. The results showed that the ternary molten carbonates (32 wt% Li2CO3, 33 wt% Na2CO3 and 35 wt% K2CO3) acted as heat medium and catalyst in the gasification process. The use of molten salts could significantly increase total gas and H2 production and simultaneously decrease the concentrations of CO and CH4 in the product gas, and also decrease the yield of condensable tar. The increase in gasification temperature and mass ratio of steam to biomass (S/B) was beneficial for H2 production process. However, excessive steam contributed slightly to the increase in H2 production and largely increased the energy consumption. The optimal S/B ratio was found to be 1.0. The feedstock after tabletting could completely immersed in molten salts, which improved the contact between biomass and molten salts and thus favored the biomass gasification for H2 production. When biomass particle size was 0.25 g/piece, the yield of H2 reached 807.53 mL/g biomass.

Digestate (DE), the residue following anaerobic digestion, has been well utilized as a potential feedstock of molten carbonates pyrolysis and catalytic reforming. The lignin of DE was converted into phenolics, guaiacols and furfural with molten carbonates pyrolysis, and further upgraded to bio-based monophenols by coupling with modified HZSM-5 catalyst. The maximum monophenols yield could achieve 7.22 g/100 g of digestate, and 81.34% of the organic phase of bio-oil at the optimum reaction conditions. The alkali-treated and Fe-loaded on HZSM-5 catalyst, with enhanced pore diameter distinctly and mild acidity, has an outstanding selectivity for monophenols and preferable anti-coking ability in integrated pyrolysis system, while with quite a low catalyst coke yield of 3.97%. The results indicated that the formation of mesopores might minimize the diffusion hindrance of the reactant molecules and reduce coke accumulation. In addition, according to the experiment conducted on a self-designed thermogravimetric analysis device, the kinetic study of the digestate with molten carbonates certificated that the reaction rate of pyrolysis had been promoted by both decreasing activation energy and intensification of heat transfer.

In this study, an efficient route to synthesizing polyethyleneimine-modified ultrasonic-assisted acid hydrochar (PEI-USAH) is developed and reported. Ultrasonic irradiation technique was used as surface modification method to shorten the crosslinking reaction for hydrochar and polyethyleneimine (PEI). The PEI-USAH showed an excellent adsorption capacity for Cr(VI) from aqueous solution. The physicochemical properties of this PEI-modified adsorbent were comparatively characterized by Fourier transform infrared spectroscopy, scanning electron microscopy, X-ray photoelectron spectroscopy, Brunauer–Emmett–Teller analysis and CNHS analysis. The effects of contact time, initial pH, and biosorbent dose on adsorption capacities were investigated. The batch adsorption experiments showed that PEI-USAH possessed the maximum adsorption capacities of 94.38 mg/g and 330.84 mg/g for initial Cr(VI) concentration of 100 mg/L and 500 mg/L, respectively. Furthermore, this adsorption process could be fitted to Langmuir adsorption and described by the pseudo second order kinetic model. Based on the above findings, PEI-USAH could be used as a potential adsorbent for removal of Cr(VI) from wastewater.

Oleaginous biomass conversion to liquid hydrocarbon biofuels has emerged as an effective solution to the energy crisis and environmental problems. In this process, the removal of oxygenated compounds will directly affect the effectiveness of subsequent biofuel applications. Herein, deoxygenation of oleic acid by catalytic cracking was conducted using five various elements (La, Ni, P, Zr and Ce) modified Al-MCM-41. The related characterizations were carried out for these catalysts, including N2 physisorption, XRD, XPS, pyridine-FTIR and NH3-TPD techniques. The results showed the mesoporous structure of Al-MCM-41 was maintained after different modifications, and these catalysts greatly improved the hydrocarbons content and physiochemical properties of biofuels. The modified catalysts tended to facilitate the decarbonylation pathway and showed high selectivity to alkane and aromatic hydrocarbons. Besides, La/Al-MCM-41 presented excellent anti-coking activity. Ni/Al-MCM-41 showed both high dehydrogenation and deoxygenation activities. The Zr modification and Ce modification had a promotion effect in the deoxidizing activity of the catalyst, owing to the formation of oxophilic metal oxides. Noteworthily, P/Al-MCM-41 displayed the best deoxidizing performance due to its high Bronsted acidity, which caused the highest hydrocarbons content (82.30 %) and the lowest fatty acids content (around 0 %) of the biofuel. Moreover, the resulting biofuel had not only low oxygen content (3.88 wt.%) and acid value (5.47 mgKOH g−1) but also a high calorific value (44.50 MJ kg−1), which could be processed into green diesel. Hence, the catalytic cracking of fatty acid over P/Al-MCM-41 has excellent potential to produce high-quality renewable fuels.

Molten carbonate pyrolysis is proposed to convert digestate (DE) into biobased monophenols coupled with a metal-modified HZSM-5 catalyst. The results indicated that Fe/HZSM-5 was the most suitable catalyst for this process. The optimum reaction conditions for the process were WHSV = 15 h−1 at a pyrolysis temperature of 430 °C and a catalytic cracking temperature of 475 °C, and 79.22 % of monophenol components were achieved in the bio-oil. A kinetic study on the digestate with carbonates indicated that the alkali metal ion in the molten carbonates attached to the β-O-4 bonds and branch methoxy group of lignin, which promoted the removal of these functional groups, resulting in a reduction in the activation energy during monophenol generation. The Fe/HZSM-5 catalyst reinforced the generation of monophenol compounds in both concentration and yield. Compared with molten carbonate pyrolysis, the Fe on the catalyst not only benefited the breaking of β-O-4 bonds and methoxy groups of lignin but also lowered the temperature during molten carbonate pyrolysis to minimize the secondary cracking of phenolic compounds.

The solubility of sulfuryl fluoride in water was experimentally measured over the pressure from P = (0 to 600) kPa and T = (283.15 to 308.15) K using isochoric saturation method. Results show that SO2F2 solubility increases with increasing pressure and decreases with increasing temperature. Using the experimental solubility data, Henry’s law constants and the thermodynamic properties such as the standard Gibbs free energy, enthalpy, and entropy changes of SO2F2 solvation were obtained. Henry’s law constant based on mole fraction and molality of SO2F2 in water vary from (432.21 to 1052.96) MPa and (7.78 to 18.96) MPa at T = (283.15 to 308.15) K, respectively.

The intensification mechanism of aqueous/organic phase reaction by the addition of magnetic polymer nanoparticles was investigated. To understand how nanoparticles intensify the liquid–liquid (L–L) reaction, three reaction enhancement strategies of mechanical agitation (MA), the addition of magnetic polymer nanoparticles (MPN) or phase transfer catalyst (PTC) were compared in Montanari oxidation system. A mass transfer mathematical model was established to describe the oxidation reaction process owing to its inherently fast characteristic of the oxidation of selected substrate (benzyl alcohol). Moreover, the influence of the nanoparticles concentration on the biphasic reaction was explored. The results indicate that the emulsification of nanoparticles is the main reason to intensify the L–L reaction, and the mass transfer specific surface area (aow) is a crucial factor to accelerate the reaction rate. In addition, the emulsion type also plays a significant role to influence the overall mass transfer coefficient (K) of substrate.

La-Fe modified Si-MCM-41 (La-Fe/Si-MCM-41) catalysts were prepared by the wet impregnation method and used in catalytic cracking of soybean oil (CCS) for biofuel production. The catalysts were characterized by BET, XRD, XPS, Py-FTIR and CO2-TPD. The results showed that the aromatics content increased with the increase in B/L value, while the content of oxygenated compounds decreased, indicating that Bronsted acid sites were the major active sites for deoxygenation and aromatization reactions. Compared with Si-MCM-41, the Bronsted acidity of LFM-6 sharply decreased from 22.49 to 5.86 μmol g−1. Accordingly, the aromatics content was reduced from 37.51 wt.% to 14.52 wt.% which was lower than the limitation (15 wt.%) according to the global environmental legislation. However, for the LFM-6 catalyst, the excessive loss of Bronsted acid sites and sharp decrease in BET surface area and pore volume led to the decrease in deoxygenation. As a result, the fatty acids content increased from 2.71 wt.% to 16.67 wt.% and the acid value reached 35.20 mgKOH g−1. When the La-Fe loading increased to 15 wt.%, part of fatty acids were converted into ketones by the active sites on Fe2O3/La2O3 and strong Lewis acid sites on catalysts. Besides, the new weak Lewis acid and basic sites on Fe2O3/La2O3 exhibited the synergistic effect on promoting the generation of alkenes. The CaO/LFM-6 composite catalysts prepared by the mechanical mixing of LFM-6 and CaO were used in CCS to reduce the acid value of biofuel. LFM-6-C-3 was proved to be an effective catalyst for CCS to produce biofuel with low aromatics (12.31 wt.%) and fatty acids (2.76 wt.%) content.

In this paper, we report the catalytic cracking of soybean oil for biofuel over γ-Al2O3/CaO composite catalysts. The influence of catalysts, cracking temperature and weight hourly space velocity (WHSV) on the products distribution were investigated. The maximum yield (70.0 wt.%) of biofuel with low acid value (6.7 mg KOH g-1) and oxygen content (5.6%), as well as high calorific value (44.2 MJ kg-1) was achieved over 35 wt.% γ-Al2O3/CaO at 480 ºC and 3.72 h-1. The paper focused on the variation of biofuel composition and cracking pathway caused by γ-Al2O3/CaO composite catalysts via gas chromatography-mass spectrometry (GC-MS) and thermogravimetric (TG) analysis. Calcium oxide would react with fatty acid to yield calcium carboxylates at 300-350 ºC, which were subsequently decomposed into hydrocarbons (57.9 wt.%) and ketones (22.6 wt.%) at 415-510 ºC. As for 35 wt.% γ-Al2O3/CaO, the addition of γ-Al2O3 was beneficial to generate alkenes (38.2 wt.%), arenes (10.6 wt.%) and alcohols (12.3 wt.%) with ketones decreasing (16.5 wt.%) via γ-hydrogen transfer reaction and disproportination.

The influence of treatment on pyrolysis characteristic and the products evolution performance of rice straw had been investigated by thermogravimetric analyzer coupled with Fourier transform infrared spectrometry(TG-FTIR). The results showed that after chemical treatment such as acid and alkali treatment, the initial pyrolysis temperature and the maximum weight loss temperature shifted to high temperature zone, the maximum weight loss rate increased, and the shoulder peaks of DTG went to fade. The ranges of E (activation energy), which was calculated through Flynn-Wall-Ozawa method, were 198∼219 kJ/mol, 184∼216 kJ/mol, 175∼205 kJ/mol, 184∼216 kJ/mol, and 205∼230 kJ/mol for raw-RS, H 2 SO 4 -RS, H 3 PO 4 -RS, HCl-RS, and NaOH-RS, respectively. The thermodynamic parameters of ΔH, ΔG, andΔS were calculated at the DTG peak temperature. After chemical treatment, most of alkali metals were removed, and the absorbance intensities of CO 2 and CO decreased comparing to that of raw sample, while the evolution of pyrolysis products including C-H, C-O-H, and C–O–C functional groups were enhanced through acid. Particularly, C=O functional groups were decreased through acid, but increased through NaOH.

Citrus sinensis is an important agricultural product with huge economic value. In this study, we report the complete mitochondrial (mt) genome sequence of Citrus sinensis for the first time. Our assembly of the Citrus sinensis mt genome resulted in a final sequence of 640,906 bp in length which contains 63 genes. Phylogenetic analysis showed that Citrus sinensis was closely related to Brassica napus and Arabidopsis thaliana, which also belong to malvids. The complete mt genome will facilitate further genetic studies of Citrus sinensis.

The ZnCl2–KCl molten salt mixture was used as the catalyst in soybean oil pyrolysis. The thermogravimetric (TG) experiments showed that the reaction pathway of soybean oil pyrolysis could be changed in the presence of molten salts. Moreover, the catalytic pyrolysis experiments were conducted in a laboratory-scale continuous stirred tank reactor (1.5 L). CaO was added to the molten salt mixture as a basic catalyst. The influence of the reaction temperature along with the CaO catalyst on molten salt pyrolysis of soybean oil was studied. The data of non-catalytic pyrolysis was also listed to explain the roles of molten salts and CaO catalyst. The results revealed that the ZnCl2–KCl molten salt mixture had a unique performance in producing diesel-like fuels. The hydrocarbons were the main part of the bio-oil, which accounted for more than 80 wt %. The acid value was 3.9 mg of KOH/g at 40 g (5 wt % to the 800 g molten salt mixture) of CaO catalyst.

In order to obtain a fuel with properties similar to fossil fuel, the catalytic pyrolysis of soybean oil was accomplished over Me-Al-MCM-41 (Me = La, Ni or Fe) mesoporous catalysts. The catalysts were synthesized by hydrothermal method and characterized by X-ray diffraction (XRD). Pyrolysis experiments were performed in a tubular reactor at the constant conditions of temperature 450 °C, weight hourly space velocity (WHSV) 6 h−1 and reaction time 4 h in the absence and presence of the above catalysts. The catalytic activity of the catalysts was studied on the base of the yields and composition of the pyrolysis products. All the pyrolysis products were distilled and classified into three categories according to the distillation temperature (DT) of fossil fuel. (a) Green gasoline (DT ≤ 50 °C); (b) Green diesel (50 °C

The effectiveness of indirect oxidation of glycerol to prepare 1,3-dihydroxyacetone (DHA) was further verified in this work. The oxidation of the 1,3-acetalized glycerol (5-hydroxyl-2-phenyl-1,3-dioxane, HPD) to 1,3-acetalized dihydroxyacetone (2-phenyl-1,3-dioxan-5-one, PDO) was successfully achieved by Montanari oxidation system (NaClO/NaBr/Magnetic recyclable TEMPO). The magnetic polystyrene nanosphere immobilized TEMPO catalyst (1.02 mmol g −1 nitroxyl radical) was readily prepared and characterized by elemental analysis, particle size analysis, and TEM. The catalyst can be used as recyclable and efficient catalyst for HPD oxidation, and high catalytic activity for up to five cycles was obtained. The target product DHA can be efficiently separated by biphasic extraction without complicated purification. The overall yield of DHA was 95.3%, and 78.1% yield with >99% purity after crystallization.

Titanium-containing mesoporous silica TiO 2 /MCM-41 (C) was prepared by impregnating MCM-41, pretreated by refrigeration at 278 K, with aqueous TiCl 4 solution as titanium precursor. In addition, TiO 2 /MCM-41 (H) was produced by same method but the support MCM-41 without refrigeration in order to investigate the influence of unrefrigerated pretreatment on the structure of TiO 2 /MCM-41. The dispersion and nature of titanium species were characterized by inductively coupled plasma mass spectrometry (ICP-MS), powder X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), UV–visible diffuse reflectance spectra (UV-vis DRS), standard Brunauer–Emmnett–Teller (BET), X-ray photoelectron spectra (XPS), scanning electron micrographs (SEM), transmission electron microscopy (TEM). The results indicate that TiO 2 /MCM-41 (C) showed better mesoscopic order, higher dispersion of titanium oxide species, stronger interaction with the MCM-41 support. But the pore size decreases from 3.4 to 2.4 nm when the titanium content increases to 76.6 mg/g. TiO 2 /MCM-41 (C2) exhibits more excellent catalytic performance than others, and the 97.6% conversion of methyl oleate (MO) and 93.1% selectivity to epoxidation methyl oleate (EMO) can be obtained at 353 K for 10 h.

Sweet sorghum is a high-yielding energy crop that leaves a large amount of lignocellulosic residues after the sugar fraction fermented to ethanol. Here, we developed a biphasic kinetic model for the dilute sulfuric acid-catalyzed hemicellulose hydrolysis of sweet sorghum bagasse at temperatures of 110–150 °C, and we then calculated the kinetic parameters for xylose production and furfural decomposition. The results indicated that elevated reaction temperatures promote the hydrolysis of hemicellulose and the degradation of xylose. The xylose yield increased in proportion to reaction time in the initial stages and then declined due to the degradation of xylose to furfural. The pre-exponential factors for the ‘easy-to-hydrolyze’ fraction, the ‘hard-to-hydrolyze’ fraction of hemicellulose and xylose degradation were 3.53 × 106, 1.80 × 105 and 0.62 min−1, respectively, and the activation energies were 60.7, 58.1 and 14.5 kJ/mol, respectively. The ideal hydrolysis condition for xylose production was 140 °C for 50 min, under which the xylose yield reached 60% of hemicellulose weight. This xylose can be used to form bioethanol and produce further downstream products.

Lignocellulose and other carbohydrates are being studied extensively as potential renewable carbon sources for liquid biofuels and other valuable chemicals. In the present study, a simple, sensitive, selective, and reliable HPLC method using a photodiode array (PDA) detector and an evaporative light scattering detector (ELSD) was developed for the simultaneous determination of important sugars (D(+)-cellobiose, glucose, xylose, and arabinose), furfural and 5-hydroxymethylfurfural (5-HMF) in lignocellulose hydrolysate. The analysis was carried out on an Aminex HPX-87H column (250 mm × 4.6 mm, 5 μm particle size). Ultra-pure water with 0.00035 M H(2)SO(4) was used as the mobile phase with a flow rate of 0.6 mL/min. The temperature of the ELSD drift tube was kept at 50 °C, the carrier gas pressure was 350 kPa, and the gain was set at 7. Furfural and 5-HMF were quantified on a PDA detector at 275 nm and 284 nm, respectively. The sugar concentrations were determined by ELSD. This method was validated for accuracy and precision. The regression equation revealed a good linear relationship (r(2) = 0.9986 ± 0.0012) within the test ranges. The method showed good reproducibility for the quantification of six analytes in corncob hydrolysate, with intra- and inter-day variations less than 1.12%. This method is also convenient because it allows the rapid analysis of the primary products of biomass hydrolysis and carbohydrate degradation.

Experiments were conducted on syngas preparation from dry reforming of methane by carbon dioxide with a DC arc plasma at atmospheric pressure. In all experiments, nitrogen gas was used as the working gas for thermal plasma to generate a high-temperature jet into a horizontal tube reactor. A mixture of methane and carbon dioxide was fed vertically into the jet. In order to obtain a higher conversion rate of methane and carbon dioxide, chemical energy efficiency and fuel production efficiency, parametric screening studies were conducted, in which the volume ratio of carbon dioxide to methane in fed gases and the total flux of fed gases were taken into account. Results showed that carbon dioxide reforming of methane to syngas by thermal plasma exhibited a larger processing capacity, higher conversion of methane and carbon dioxide and higher chemical energy efficiency and fuel production efficiency. In addition, thermodynamic simulation for the reforming process was conducted. Experimental data agreed well with the thermodynamic results, indicating that high thermal efficiency can be achieved with the thermal plasma reforming process.

Undecylenic acid methyl ester (UAME) was continuously produced from methyl ricinoleate using a microwave-assisted pyrolysis system with atomization feeding. The UAME yield of 77 wt.% was obtained at 500 °C using SiC as the microwave absorbent and heating medium. The methyl ricinoleate conversion and UAME yield from microwave-assisted pyrolysis process were higher than those from conventional pyrolysis. The effect of temperature on the pyrolysis process was also investigated. The methyl ricinoleate conversion increased but the cracking liquid yield decreased when the temperature increased from 460 °C to 560 °C. The maximum UAME yield was obtained at the temperature of 500 °C.

In order to investigate the effects of molten salts on pyrolysis characteristics of rice straw, the pyrolysis behaviors of rice straw had been investigated with thermogravimtirc analysis by changing cations (Na+, K+) and anions (Cl-, CO32- and SO42-) of the molten salts, respectively. The results indicated that the pyrolysis of rice straw was occurred in the range of 200°C and 400°C. With the increase of heating rate, hysteresis was existed during the pyrolysis process, and the maximum weight loss rate increased. The pyrolysis happened at a lower temperature range and the volatile matter vapored easily under the role of CO32-, and SO42- had advantages of fixing charcoal under the same cation conditions. Compared with Na+, it was easier for K+ to generate charcoal under the same anion conditions. Integration method Ozawa was used in kinetic analysis on the samples processed by deducting the added salts, the results showed that the activation energy of rice straw under the role of NaCl, Na2SO4 and KCl decreased compared with that of the sample without additives, while the activation energy processed by Na2CO3 increased. This research can provide a certain reference for the exploitation and utilization of agricultural residues.

Sawdust, a renewable by-product of furniture manufacturing industry, is an energy source that can be utilized to meet the increasing demands for energy. Pyrolysis of sawdust was performed in a self-designed reactor under the conditions of nitrogen atmosphere, the effect of feeding rate, flow rate of sweeping gas, sawdust type, and inorganic salts additive on the pyrolysis product yields from sawdust have been investigated. The results shows that the char yield increased gradually with the increasing of feeding rate, the maximum yield of liquid and gaseous attained at the feeding rate of 1.36g/min; the liquid yield decreased gradually with the increasing of sweeping gas flow rate, and the maximum of gaseous attained at the flow rate of 100L/h; different kinds of sawdust can be used to produce different pyrolysis products, and ZnCl2 can retrain the formation of liquid and char obviously, the effect on formation of gaseous was slight.

The pyrolysis of soybean oil was studied in a continuous fixed bed reactor. The effect of reaction temperature (400-550°C) and feed rate (0.21-1.04 g·min-1) were studied over the yield of the liquid condensates. The maximum yield (76.0%) of liquid condensate was obtained at 450°C pyrolysis temperature and 0.62 g·min-1 feeding rate. The catalytic pyrolysis experiments were studied over several oxides and zeolite catalysts. The calcium oxide presented a good catalytic result. The acid value decreased from 83.6 mg KOH·g-1 to 8 mg KOH·g-1 when in the presence of excess calcium oxide, and an attractive yield (41.1%) of diesel-like fuel was obtained. The compositions of the products were analyzed by gas chromatograph and mass spectrometry (GC-MS). Some of the fuel properties such as density, viscosity and heat value were also studied. The results showed the diesel-like fuel produced with catalytic pyrolysis of soybean oil had higher qualities and might serve as a substitution of the fossil fuel.

Wastewater from chemical plant, refinery and pharmaceutical factory contains many kinds of aromatic compounds. Wastewater including aromatic compounds is hazardous and difficult to be biodegraded. This study concerned the method of extracting aromatic compounds from the wastewater using biodiesel as extracting solvent. Biodiesel as solvent has some special characteristics: its solubility in water is smaller, its flash point is higher, it is nontoxic, and it is biodegradable. In this work, the solute removal rate, COD removal rate and solvent recovery were studied. In addition, the multistage countercurrent extraction experiments were carried out. The results showed that the multistage extraction rates of aniline, nitrobenzene and phenol were greater than 98.67%. The recovery performance of biodiesel was better. Biodiesel is a better extracting solvent for the wastewater containing aromatic compounds.

Hydrogen production from biomass pyrolysis with molten NaOH had achieved high yield of hydrogen, but the molten mixture of Na 2 CO 3 and NaOH was obtained during the process of hydrogen production, since Na 2 CO 3 can be acted as a product and NaOH is recycled, Na 2 CO 3 and NaOH need to be separated. In this paper, the separation of molten mixture of NaOH and Na 2 CO 3 was investigated through molten crystallization. The influences of thermostatic time, depart temperature, teperature controlling way and molar content on the separation results were studyed. The results showed that the suitable thermostatic time was 30 minutes, and temperature directly dropping to desirable temperature was in favor of improving the percentage of NaOH The suitable separation temperature was impacted by the content of Na 2 CO 3 . The quality was kept constant when the molar content of Na 2 CO 3 is 25%, and the appropriate separation temperature is 370°C, which is higher 80°C than that of the molar content of 10% Na 2 CO 3 . This article provides some references for separating the residue which is attained in the process of hydrogen production by pyrolysis of biomass in molten NaOH.

The demand for sustainable development has led to a growing interest in biomass energy. Molten salts, such as alkali metallic salts, have been applied in biomass pyrolysis because of their good thermal stability, low vapour pressure, large heat capacity, large thermal conductivity, high solubility, low viscosity, and chemical stability. Using thermogravimetric analysis, this work studied the influence of sodium and potassium carbonates as additives for pyrolysis. Rice straws were mixed at different ratios with two alkali carbonates (Na 2 CO 3 , K 2 CO 3 , and their mixture, Na 2 CO 3 -K 2 CO 3 ). The weight of rice straw decreased at around 200 and 380 oC in the presence of carbonates. Temperatures of initial release of volatiles decreased with the increase of mass of salt. The shoulder of the differential thermogravimetric curves appeared earlier under the catalysis by carbonates. The char yield of rice straw with added eutectic molten salt was nearly the minimum compared with that obtained with other salts. Based on this experiment, two reaction models for biomass pyrolysis were proposed. The models can describe the pyrolysis process satisfactorily over the whole temperature range. The kinetic parameters in the different reaction models were calculated by fitting single experiments and by multivariate regression. The results illustrate that the salts can decrease the activation energy and alter the paths of rice straw pyrolysis, and the catalytic activity of eutectic salts is higher than those of the individual salts.

Pyrolysis of cellulose with different catalysts has been conducted in a fixed-bed reactor. Micro-mesoporous composite molecular sieves of ZSM-5(38)/A1-MCM-41 with different Si/A1 ratios were prepared under hydrothermal conditions. With powder X-ray diffraction (XRD), the catalyst samples were characterized. GC-MS was used to analyze the bio-oil composition. The effects of catalysts on the pyrolysis product yields were investigated and the results were compared with the results of experiments performed without catalyst under the same pyrolitic conditions. The presence of the catalysts decreased the liquid yield, while increased the moisture content. The major improvement in the quality of bio-oil with the use of catalysts was the increase of DL-2,3-Butanediol. ZSM-5(38)/A1-MCM-41(20) favored the formation of phenol and 2-methoxy-phenol. In addition, these catalysts were all benefit for the generation of small molecular compounds. Also, it was found that ZSM-5(38) was better for the production of C4-C5 compounds. And micro-mesoporous composite molecular sieves mainly promoted the production of C6-C8 compounds.

In order to investigate the effects of pyrolysis conditions on bio-oil production from biomass in molten salt, experiments of biomass pyrolysis were carried out in a self-designed reactor in which the molten salt ZnCl2-KCl (with mole ratio 7/6) was selected as heat carrier, catalyst and dispersion agent. The effects of metal salt added into ZnCl2-KCl and biomass material on biomass pyrolysis were discussed, and the main compositions of bio-oil were determined by GC-MS. Metal salt added into molten salt could affect pyrolysis production yields remarkably. Lanthanon salt could enhance bio-oil yield and decrease water content in bio-oil, when mole fraction of 5.0% LaCl3 was added, bio-oil yield could reach up to 32.0%, and water content of bio-oil could reduce to 61.5%. The bio-oil and char yields were higher when rice straw was pyrolysed, while gas yield was higher when rice husk was used. Metal salts showed great selectivity on compositions of bio-oil. LiCl and FeCl2 promoted biomass to pyrolyse into smaller molecular weight compounds. CrCl3, CaCl2 and LaCl3 could restrain second pyrolysis of bio-oil. The research provided a scientific reference for production of bio-oil from biomass pyrolysis in molten salt.

Characteristics of copyrolysis polyethylene (PE) with greenhouse gas carbon dioxide (CO 2 ) was investigated in a horizontal DC plasma jet reactor, for the aim to adjust the H 2 /CO molar ratio in the gaseous products in a wide range to further synthesize liquid fuel. For comparison, pyrolysis PE alone as well as pyrolysis CO 2 alone was also studied in light of CO yield. Results showed that: in case of plasma pyrolysis PE alone, product streams included combustible gas and solid carbon, and the main components of the gaseous products consisted of a large amount of H 2 achieved at 21.3 vol % and a small amount of low molecular hydrocarbon, CO was not determined in the gaseous products thanks to PE being hydrocarbon polymer. In terms of H 2 yield performance, the horizontal plasma jet reactor under development was superior to the downward mode. In case of plasma pryolysis CO 2 alone, just a small amount of CO obtained from the decomposing reaction of CO 2 , and the CO concentration in the gaseous products was less than 5%. In case of plasma copyrolysis PE with CO 2 , a wide range of H 2 /CO molar ratio in the gaseous products can be obtained with varying the inlet CO2 concentration, and the product of CO obtained mainly from the gasified reaction of carbon with CO 2 , in which carbon generated from plasma pyrolysis PE. In this paper, the H 2 /CO molar ratio was adjustable in the range of 1 to 12 from plasma copyrolysis PE with CO 2 . Thus, a significant synergy effect can be observed from copyrolysis PE with CO 2 in terms of the CO yields.

Ruthenium-based materials are the second-generation catalysts for ammonia synthesis. Ruthenium is less inhibited by ammonia, less sensitive to poisons, and more active than the traditional iron-based catalyst. The relatively high cost of Ru compared to that of iron requires a high dispersion of the metal on a suitable support. Carbon-supported Ru catalysts with promoters have been reported to be active for ammonia synthesis. The ultrasonic technique has been proven to be beneficial to the preparation of supported catalysts. In this paper, the effects of ultrasonic treatment on the surface texture, oxygen groups of activated carbon (AC) as well as ruthenium dispersion were investigated by the employments of N(2) physisorption, TPD-MS and CO chemisorption respectively. It have been shown that ash content in AC can be effectively eliminated by ultrasonic pretreatment, at the same time, the BET surface area and total pore volume are reduced, and the amount of the decomposable surface oxygen groups are decreased. Furthermore the ash content decrease and the mesopore surface area increase with the ultrasonic power increasing. The activities of a series of barium-potassium-promoted Ru/AC catalysts for ammonia synthesis were tested at 10,000 h(-1), 10.0 MPa and 400 degrees C. The results show that the activities of Ru/AC catalysts which were prepared by ultrasonic treatment are greatly increased, and the optimum pretreatment power is 100 W. The ash content of this carbon support is decreased from 1.39% to 1.15%. As a result, the catalytic activity is improved from 65.3 to 83.8 mmol g(-1) h(-1).