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Copyright of China Forest Products Industry is the property of China Forest Products Industry Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The ecologically friendly disposal of arsenic-enriched plants is the key link to achieve the industrial development of phytoremediation, and plays a restricting role in the high-quality development of soil heavy metal pollution control. Conventional treatment methods of hyperaccumulators mainly include incineration and landfill, but these methods may lead to secondary pollution of heavy metals. Hydrothermal liquefaction can transform agricultural and forestry waste with low energy density into liquid biofuel with high energy density. It has the advantages of low reaction temperature, low energy consumption, water as solvent and no need for drying as raw material. As a typical representative of arsenic contaminated soil phytoremediation, the effects of ethanol ratio and water cycle times on hydrothermal oil production and heavy metal arsenic distribution of centipede grass were investigated in this study using Pteris vittata L. as raw material and ethanol-water reaction co-solvent system. The results showed that under the conditions of 60% ethanol concentration and 3 cycles of aqueous phase, the highest yield of liquefied bio-oil was 51.08%, and its calorific value was 29.15 MJ/kg. The reasons for the increase of biooil after water phase circulation in the co-solvent system are as follows: 1) the organic acids (acetic acid, etc.) in the recycled water phase have an acid catalytic effect to promote biomass liquefaction; 2) Compared with pure water, ethanol in cosolvent has lower liquefaction critical point and dielectric constant, which promotes biomass degradation and hydrolysis; 3) Ethanol can esterify the acid in the aqueous phase to improve the yield of bio-oil. Bio-oil is mainly composed of esters (>80%), phenols, alcohols, ketones, hydrocarbons, etc. With the increase of water cycle times, the esters and phenols in bio-oil increased and the high boiling point compounds decreased, the bio-oil yield and energy recovery increased by 58% and 32.23%, respectively. This may be affected by esterification of ethanol with fatty acids. Moreover, aqueous cycle can promote the degradation of high boiling point compounds to low boiling point compounds, which may be related to the low boiling point compounds produced after the reuse of liquefied water phase with the addition of 60% ethanol-water cosolvent. After water phase circulation, the content of bio-oil distillate (boiling point <538 ℃) increased from 65.57% to 71.70%, which show that ethanol-water co-solvent can produce high quality bio-oil in aqueous phase recycling. Finally, the migration and transformation of arsenic in enriched plants during liquefaction were also investigated. After aqueous phase circulation, more than 80% of heavy metal arsenic was mainly distributed in the water phase and the concentration of arsenic increased to 215.05 mg/kg. The enrichment and removal of arsenic during liquefaction plays an important role in the post-disposal of arsenic-enriched plants, which greatly reduces the secondary pollution of heavy metals. Therefore, water phase recycling is an effective way to obtain high-yield bio-oil and arsenic enrichment from liquefaction disposal of arsenic-enriched plants, which provides a new idea for ecologically friendly disposal of arsenic-enriched plants, promotes the industrial development of phytoremediation, and speeds up the treatment of soil heavy metal pollution. To provide theoretical support for green, low-carbon and new quality development in the process of heavy metal pollution control in our country. [ABSTRACT FROM AUTHOR]

Agricultural residue is an important biomass resource in China. Utilization of agricultural residue for production of high-quality fuel oil is an attractive and challenging topic towards the goals of “Carbon Peaking and Carbon Neutrality”. Biomass hydropyrolysis integrated with volatile catalytic hydrogenation is a new process that can efficiently improve the yield and quality of bio-oil. This work is purposed to explore this new biomass conversion technology by laboratory experiments using a tandem pressurized fixed bed reactor. A bimetallic molecular sieve catalyst (NiMo-HZSM-5) was prepared by an impregnation method and used for catalytic hydrogenation. Biomass was hydropyrolyzed under a condition of 5 MPa H2 pressure, 15℃/min heating rate and 700℃ final temperature to generate volatile matter, which was online hydrogenated through the NiMo-HZSM-5 catalyst bed under a condition of 5 MPa H2 pressure, 320℃ reaction temperature and 26 s residence time (corresponding to space velocity of 112.5 h−1 ). The paper firstly presents the oil production results of three types of agricultural residue, corn stalk, cotton stalk and peanut straw by the catalytic hydrogenetion. The paper is then devoted to further clarifying the conversion characteristics of different biomass fiber constituents by means of the water washing and acid washing pretreatments of three agricultural residues as well as by adopting cellulose and lignin as model compounds. Results showed that in the case of non-catalytic hydrogenation, all of the bio-oils obtained from three agricultural residues contained oxygenates and aromatic hydrocarbons as two main classes of compounds, and that from peanut straw also contained a high proportion of nitrogenous compounds. In contrast, all of the bio-oils derived from three agricultural residues by the catalytic hydrogenation (CH bio-oils) contained almost neither oxygenates nor nitrogenous compounds. The yields of CH bio-oils reached 10.3%–15.9% for three agricultural residues. The CH-bio-oils were composed of 73.0–84.8% saturated aliphatic hydrocarbons (mainly cyclopentanes, cyclohexanes, and perhydro- naphthalenes), 6.1%–13.1% partially hydrogenated aromatic hydrocarbons (mainly di-, tetra-hydronaphthalenes) and a small amount of monocyclic aromatic hydrocarbons. The result highlights that the two-stage process of hydrogenation pyrolysis integrated with NiMo-HZSM-5 catalytic hydrogenation can effectively convert agricultural residue into a kind of high-quality bio-oil composed mainly of alicyclic hydrocarbons. The water washing could remove about half of neutral extractives from each of three agricultural resides. After the water washing, three agricultural residues showed increases in the yields of CH bio-oil to 18.1%–18.5%, suggesting that neutral extractives are less conducive to the production of CH bio-oil compared to other fiber components. The acid washing enabled cellulose and lignin to be left in the agricultural residues as main components. Via this pretreatment, the yields of CH bio-oil increased to 18.2%–22.5% for three agricultural residues, with cotton stalk having the highest yield. The yields of typical aliphatic hydrocarbon compounds (methyl-cyclopentane, methyl-cyclohexane and decahydro-naphthalene) from all three agricultural residues were increased by the acid washing. The study using model compounds revealed that cellulose is a fiber for not only achieving a high yield of CH bio-oil but also selectively producing aliphatic hydrocarbon compounds such as cyclopentane, cyclohexane, and decahydro-naphthalene. Meanwhile, lignin has a lower yield of bio-oil, and it tends to produce monocyclic aromatic hydrocarbons. Lignin can also generate cyclohexane compounds and partially hydrogenated polycyclic aromatic hydrocarbons, but it has a low propensity to the formation of cyclopentane compounds. This study has provided a new technical route to utilizing agricultural residues for high-efficient production of fuel oil. [ABSTRACT FROM AUTHOR]

This study explores the potential of bio-oil in rejuvenating the performance of aged asphalt. A bio-oil with high rejuvenation capacity was chosen to determine the optimal dosage. Three types of bio-oil, namely vegetable pitch. waste cooking oil, and industrial animal oil, were employed as rejuvenators to treat aged SBS modified asphalt. The impact of bio-oil type and dosage on the various properties of aged asphalt was evaluated through the measurement of the penetration, ductility. softening point. Brookfield viscosity of the bio-oil recycling asphalt, and thin film oven test. The results indicated that all three types of bio-oil possessed some recycling capability towards the fundamental performance and aging resistance of aged SBS modified asphalt. Waste cooking oil exhibited a stronger rejuvenation effect and offered higher social and economic benefits, followed by namely vegetable pitch and industrial animal oil. Waste cooking oil has been selected as the optimal recycled bio- oil, and a 4% content can completely restore the viscosity and high-temperature performance of aged SBS modified asphalt. thus being determined as the optimal content. [ABSTRACT FROM AUTHOR]

Bio-oil is one type of liquid product from the pyrolysis liquefaction of biomass. The heat-sensitive liquid with high water content and complex components can be further processed and then refined for the subsequent application. Moreover, the more large molecules of phenolics and sugars in the bio-oil are prone to serious coking on the catalyst during refinement. In this study, a systematic investigation was carried out on the distribution pattern of molecular distillation fractions in the different bio-oils. Two feedstocks (pine and maize stover) and temperatures (500, 550, and 600 ℃) were selected to evaluate the separation of bio-oils using molecular distillation. The pyrolysis liquefaction test was carried out by a bubbling fluidized bed reactor. The experiment showed that the bio-oil components were dominated by acids, aldehydes, ketones, phenols, and sugars. Both feedstock and pyrolysis temperature dominated the yield of bio-oil. Specifically, the yield of light components in pine biooil decreased continuously from 21% to 11% with the increase in pyrolysis temperature. While the yield of light components in maize stover bio-oil was stabilized at about 20%. There was a strong polarization in the mean free path of each component in the bio-oil at high temperatures. Once the pyrolysis temperature increased from 500 to 600 ℃, the evaporation percentage of pine light oil increased to 92%, while that of maize stover light oil increased to 86%. The molecular distillation was realized to separate more than 90% of water, acids, ketones and small molecules in the bio-oils. But it was difficult to separate the larger molecules of sugars. The separation of phenolics differed greatly from the number of phenolic hydroxyl groups; Monophenolics were easily vaporized, and thus more enriched in the distillation fraction (DF); While diphenolics were more difficult to be vaporized and thus more enriched in the residual fraction (RF). Higher pyrolysis temperatures promoted the conversion of methoxy into the phenolic hydroxyl groups in the bio-oil phenolics. The increasing number of phenolic hydroxyl groups in phenolics also resulted in the transfer of phenolics from the DF to the RF. The separation factor was introduced to evaluate the separation effect of various compounds in the bio-oil after molecular distillation. Among them, the separation factors of acids, ketones and mono phenolics in the bio-oil reached more than 0.9, whereas, less than 0.1 was found in the diphenolics of sugar. Therefore, the different compounds were enriched by more than 90% in their fractions. Molecular distillation was also used to increase the calorific value of bio-oils, where the water content and pH of bio-oils were reduced to obtain the higher-quality RF fractions. The effective separation was realized to improve the different bio-oils. The DF contained mainly acids, ketones and small-molecule phenols, while the RF was dominated by sugars and large-molecule phenols. The enrichment degree of most compounds in the bio-oils was more than 90%, except for the compounds, such as glycolaldehyde and benzofuran. This finding can provide a strong reference for the separation and subsequent refinement of biooil after biomass-fast pyrolysis. [ABSTRACT FROM AUTHOR]

How to dispose heavy metal-rich plant harvest in a green, efficient and resource ・ based manner is an urgent technical problem for the industrial development of phytoremediation of heavy metal・containinated soil・ Using ramie as raw material and water as reaction solvent, the effects of reaction temperature, reaction time and acid-base catalysts on the oil yield and heavy metal migration of ramie were investiga・ ted. The results showed that the highest yield of ramie liquefied bio-oil was 20. 86% at 275 °C, 30 min and 5% HCOOH, and 让s calorific value was 30. 68 MJ/kg・ The organic components of bio・oil in blank group were mainly composed of alcohols, hydrocarbons, acids, ketones and N・containing compounds・ The contents of hydrocarbon and ester compounds in liquefied bio-oil in HCOOH group were increased, while the contents of hydrocarbon, alcohols and acids in bio・oil in NaCO2 group were decreased・ In addition, more than 85% of heavy metals (Cd, Pb, Cu and Cr) are retained in the solid phase residue, while As is mainly transferred to the aqueous phase, and the heavy metal content in bio-oil is less than 4%. [ABSTRACT FROM AUTHOR]

Copyright of Biomass Chemical Engineering is the property of Editorial Office of Biomass Chemical Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Plastics Science & Technology / Suliao Ke-Ji is the property of Plastics Science & Technology Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Dielectric barrier discharge reaction technology is an effective way to achieve the hydrogenation and upgrading of thermosensitive bio-oil under mild reaction conditions. To analyze the hydrogenation reaction pathway and mechanism of each component of bio-oil under the condition of dielectric barrier discharge, hydrogenation experiments and theoretical investigation on the simulated bio-oil prepared by model compounds were conducted based on the previous studies. The results show that butyric acid and butanol are mainly esterified to produce butyl butyrate, and the hydrogenation liquid product of hydroxyl acetone is mainly isobutyl aldehyde. Furfural is mainly saturated by hydrogenation to produce furfuryl alcohol, and the guaiacol is mainly broken by methyl to produce catechol and further hydrogenation to cyclohexene. The conversion rates of model compounds of butyric acid, butanol, furfural, hydroxyacetone, guaiacol, ethyl acetate and cyclohexane are 82.86%, 85.95%, 82.05%, 83.79%, 51.70%, 68.54% and 13.03%, respectively. Acid, aldehyde and ketone can lead bio-oil to poor corrosion and thermal stability and show high reactivity. [ABSTRACT FROM AUTHOR]

Copyright of Biomass Chemical Engineering is the property of Editorial Office of Biomass Chemical Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Chemistry & Industry of Forest Products is the property of Chemistry & Industry of Forest Products Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Shenyang Agricultural University is the property of Journal of Shenyang Agricultural University Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Biomass Chemical Engineering is the property of Editorial Office of Biomass Chemical Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Zhengzhou University: Engineering Science is the property of Editorial Office of Journal of Zhengzhou University: Engineering Science and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Biomass has been one of the most promising renewable energy substitutes for fossil fuels. However, the bio-oil production from biomass pyrolysis has been greatly limited the application value, due to the complex components and low enrichment of available components. An effective way can be to selectively regulate the pyrolysis reaction using the catalyst. Among them, the coal fly ash can be widely expected to serve as the low-cost and high-efficiency catalytic medium, due to the rich pore structure and inorganic mineral composition. Generally, solid waste is produced by the combustion of pulverized coal in the boiler of the thermal power plant. More importantly, CO2 rich in carbon source can participate in the pyrolysis process to enrich the platform compounds. Therefore, CO2 and coal fly ash can be applied for the biomass pyrolysis process, in order to improve the quality of bio-oil for the high-value utilization of solid wastes. It is very necessary to explore the co-pyrolysis behavior of coal fly ash and biomass in the CO2 atmosphere for the goal of carbon neutralization. This work aims to investigate the effects of coal fly ash on the distribution of the products during the pyrolysis of maize stalks with different particle sizes. The liquid products were also characterized by catalytic pyrolysis under N2/CO2 atmosphere. The coupling mechanism of CO2 and coal fly ash was proposed, according to the experimental data. Specifically, the particle sizes of corn straw were ranged from 0.1-0.16, 0.17-0.21, 0.22-0.30, and 0.31-0.45 mm, respectively. The mixing ratio of maize stalk and coal fly ash was 1:1. A catalytic pyrolysis experiment of maize stalk was carried out in a fixed bed reactor, where the temperature was 550±1 ℃, the flow rate of N2 was 100 mL/min, and the flow rates of CO2 were 40, 70, 100, and 130 mL/min. The obtained bio-oil was detected using an elemental analyzer and Gas Chromatography-Mass Spectrometry (GC-MS). The results showed that the particle size dominated the heat and mass transfer behavior of the biomass pyrolysis process. The increase of particle size led to the increase of bio-oil production first and then the decrease in only single biomass pyrolysis. The yield of semi-coke decreased, but the gas increased. The addition of coal fly ash was conducive to the formation of bio-oil, where the maximum bio-oil yield was 44.32% using 0.17-0.21mm of biomass particles. Coal fly ash was also greatly contributed to the biomass pyrolysis with the large particle size, where the bio-oil yield increased by 8.94 percentage point, compared with the blank sample. The main reason was the synergistic effects among metal components in the coal fly ash, thereby enhancing the heat and mass transfer efficiency inside and outside biomass particles. In addition, CO2 was introduced to inhibit the formation of bio-oil, and the liquid yield decreased with the increase of CO2 flow rate in the system. The co-pyrolysis of coal fly ash and biomass with small particle size was conducive to enhancing the selective phenolic compounds. The strong binding ability of CO2 and hydrogen radical was further promoted to enrich the phenolic compounds in the system. The methoxyphenol compounds increased significantly among phenolic compounds in the bio-oil. The relative content of phenolic compounds was the highest- when the flow rate of CO2 was 40 mL/min. [ABSTRACT FROM AUTHOR]

The effect of alkali/alkaline earth metals (AAEM) on biomass pyrolysis and the composition of pyrolysis products can provide important theoretical basis for the study of biomass pyrolysis characteristics and the efficient utilization of pyrolysis products. In this paper, pine sawdust was used as pyrolysis raw materials, and the acid washed sample was soaked with potassium, calcium, sodium and magnesium chloride solution, respectively. The samples were rapidly pyrolyzed at 500℃under Ar atmosphere. The influence of four metal ions on the composition and distribution of pine sawdust pyrolysis products was investigated. The pyrolysis characteristics of each sample were investigated by thermo-gravimetric analysis. The tar components of the fast pyrolysis were investigated by gas chromatography/mass spectrometry (GC/MS). The results show that: AAEM has obvious catalytic effect on pine sawdust, the existence of AAEM ions can improve the yield of pyrolysis gas and solid, reduce the yield of tar; AAEM can reduce the pyrolysis temperature and make the pyrolysis easier; the tar components of fast pyrolysis mainly include phenols, ketones, aldehydes, aromatics, alcohols, dehydrated sugars, furans, acids and AAEM will cause changes in the relative contents of these substances, especially furans and aromatics. These experimental results provide an important reference for optimizing the pyrolysis conditions of biomass and improving the quality of pyrolysis bio-oil. [ABSTRACT FROM AUTHOR]

Copyright of Transactions of China Pulp & Paper is the property of China Pulp & Paper Magazines Publisher and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Biomass has drawn much attention, due to renewable and green energy against environmental degradation and energy shortage in recent decades. Pyrolysis of biomass in anaerobic/anoxic conditions can be an important way to produce high value-added biofuels, such as alkanes, hydrocarbons, aromatics, and phenol derivatives. However, the bio-oil from biomass direct pyrolysis is a type of complex oxygen-containing mixture, composed of organic acids, aldehydes, ketones, alcohols, phenols, and sugars. The bio-oil is difficult to be directly used, because of high acidity, low calorific value, and thermal stability. In this study, a combination of hydrochloric acid washing and torrefaction pretreatment was proposed to improve the quality of bio-oil from biomass pyrolysis, in order to deal with the high oxygen content, strong corrosiveness, and a wide variety of compounds in bio-oil. The physical and chemical properties of sweet sorghum straw were measured before and after pretreatment. The results showed that the simple pickling was beneficial to the generation of volatiles, whereas, the torrefaction pretreatment alone reduced the ratio of H/C and O/C, while increased the energy yield up to 95.13%, particularly on the increased generation of carbon. The combination of pickling and torrefaction pretreatment also significantly increased the biochar and non-condensable gases. A pyrolysis test was carried out in a horizontal tube furnace (OTF-1200X). The high purity N2 was used as the protective gas, and the flow rate was 100 mL/min. The program was set to raise the temperature to 500 ℃, and the quartz boat containing 10 g samples was quickly pushed into the central constant temperature section of the tubular furnace. At this time, the temperature changed within ±2 ℃ and returned to 500 ℃ within 1 min. The heating stopped after 30 min. The test results showed that the acid washing, torrefaction, and combined pretreatment reduced 62, 58, and 68 compounds in the bio-oil from sweet sorghum straw pyrolysis, compared with 111, respectively, while the contents of ketones, acids, and furans were all reduced. There was a weak catalytic effect of most metal ions that were removed by pickling on the acetyl group in the pyrolysis process. A significant decrease was observed in the acetic acid content and the acidic components in the bio-oil for a better corrosion resistance of bio-oil. Furthermore, the pickling and torrefaction pretreatment improved the carbohydrate compounds, and the precious D-Allose, a kind of very rare monosaccharide in nature, particularly with the very limited synthesis amount but a high medicinal value. Allosose was expected to inhibit the proliferation of tumor cells, while protecting islet β cells of diabetic animals. In addition, the combined pickling and pretreatment also promoted the formation of nonanoic acid and valeric acid, with a high yield of furfural, where the yield was higher at about 500 ℃. Furfural was a kind of chemical product with high added value, widely used in resin, varnish, and organic reagent in the food industry. Simple torrefaction was beneficial to increase the relative content of cellulose in biomass, rich in -OH functional group, thereby for the high content of phenols in bio-oil. Although no new substances were formed, the pH value was significantly improved in the bio-oil. [ABSTRACT FROM AUTHOR]

Copyright of Chemistry & Industry of Forest Products is the property of Chemistry & Industry of Forest Products Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Utilization of duckweed in wastewater treatment has gained ever-increasing attention in recent years. Meanwhile, the harvested duckweed can offer potential to use for energy production. As a promising thermochemical conversion technology, the pyrolysis can convert the solid fuel to bio-char, bio-oil and combustible gas products with high efficiency. However, the duckweed generally has a high ash content, such as alkali, alkali earth metals, and minerals, due to the special cultivation environment and harvesting. This has posed a great challenge for the thermochemical conversion and the quality of pyrolysis products. Therefore, the pretreatment, such as acid washing, is necessary to reduce the content of these minerals in the conversion process. In this work, a pyrolysis experiment was performed on the duckweed, which was normally used to mitigate the water pollutions in Erhai Lake, Yunnan Province, China. Acid-washing was firstly conducted for the duckweed to remove the inorganic species in the fuel. Then, the pyrolysis experiments of the raw and acid-washed duckweed were carried out in a fixed bed reactor at 400-900 ℃, with an interval of 100 ℃, in order to investigate the effect of acid-washing on the yield and composition of solid, liquid and gaseous products. The results showed that the acid treatment can effectively remove most of the alkali, alkaline earth metals, and the majority of phosphorus in the biomass. Meanwhile, the fixed carbon and C content were greatly improved. The heating value increased substantially to 19.4 kJ/kg, which was close comparatively to the woody biomasses with a heating value of 17.6-20.8 kJ/kg. The results of pyrolysis experiments showed that the solid products decreased but the gas products increased with the increase of temperature in both raw and acid-washed fuel. Conversely, the liquid products increased firstly to the maximum at 500 ℃, and decreased with the increase of temperature. After treatment, the solid and gas products decreased by 1.43-8.02%, and 2.81-9.89%, respectively, with the increase of liquid product by 1.63-16.72%. In acid-washed duckweed, the solid, liquid and gas products changed slightly, when the pyrolysis temperature was higher than 600 ℃. In addition, there were more significant differences of liquid and solid products between the raw and acid-washed duckweed at 700-900℃. In the gas products, the acid treatment relatively reduced the release of CO, CO2, CH4, and H2. However, the reduction of CO2 was much higher than that of the other gases, and thereby the heating value of gas products increased by 5-155%, compared with that from the raw duckweed. In the solid products, both the fixed carbon and C content of the char samples from the acid-washed duckweed increased significantly with the decrease of ash and O content, compared with that from the raw duckweed. The composition of bio-oil changed slightly after acid treatment. Specifically, there was a slight change trend of N-containing species, aliphatic hydrocarbon, and aromatic hydrocarbon after acid treatment. However, the content of phenols, furans and carbonyl compounds in bio-oil decreased with the significant increase of alcohols and ether at 400-600 ℃. The acid treatment can greatly improve the quality of gas and solid products, where the content of combustible compounds increased for the high heating value. In the liquid products, both the raw and acid-washed duckweed showed potential utilization in producing N-containing species and aromatic hydrocarbon at low and high temperature. [ABSTRACT FROM AUTHOR]

For investigating the pyrolytic characteristics and mechanism of spent mushroom substrate, this research studies the thermogravimetric (TG) curve and differential thermogravimetric (DTG) curves of spent mushroom substrate (SMS) of Shiitake mushroom at different heating rates, using the combination of thermogravimetry and thermogravimetry-infrared the pyrolysis in nitrogen atmosphere. A peak splitting technique was used to analyze the DTG curve, thereby to calculate the activation energy E, reaction order n, frequency factor A, further to obtain the precipitation characteristics of the pyrolysis products. A pyrolysis experiment at constant temperature for SMS of Shiitake mushroom was performed on a fixed bed, where the experimental temperatures were set at 500, 550, and 600 ℃, thereby to analyze the yield and composition of three-phase products. Industrial analyzers were used to characterize and compare raw materials and pyrolysis semi-coke, where the FTIR was used to perform functional group analysis on semi-coke, the GC-MS was used to analyze pyrolysis tar, and a flue gas analyzer was selected to measure pyrolysis gas online. The results showed that the pyrolysis of SMS of Shiitake mushroom can be divided into three stages: the water precipitation, the pyrolysis, and the carbonization stage. The pyrolysis stage dominated during the entire process with the temperature range of 250-550 ℃, where the weight loss reached 58%. There was no obvious effect of heating rate on pyrolysis. Nevertheless, the TG and DTG curves of the sample shifted to the high temperature zone, as the heating rate increased. The apparent activation energy for the pyrolysis of SMS of Shiitake mushroom was 66.33 kJ/mol, easier for pyrolysis due to the low apparent activation energy. In the pyrolysis experiment performed on the fixed-bed at constant temperature, the main components of the pyrolysis gas of SMS of Shiitake mushroom were CO2, CO, CH4, H2, ranking in order: CO2, CO, CH4, H2, which was well consistent with the measured data from the TG-FTIR. At 600 ℃, the contents of CO and H2 increased significantly. The data of gas analysis showed that the overall gas yield of the reaction was well consistent under the experimental conditions, indicating that the pyrolysis reaction was fully completed. At 500 ℃, the liquid products of pyrolysis were mainly silicon-containing organics, showing that there was a certain amount of silicon in the raw material. The main component of the bio-oil from the pyrolysis of the mushroom residue was CxHyOz, as the pyrolysis temperature increased, indicating a promising potential application using the pyrolysis of mushroom residue to produce the bio-oil. In the semicoke from the slow pyrolysis of mushroom residue, the dominated component was fixed carbon, compared with the raw material, indicating the proportion of volatile contained in pyrolytic semicoke decreased significantly. There was no significant difference in the types of functional groups in the pyrolysis semicoke at the three temperatures, whereas, there were obvious characteristic peaks of alcohols, carboxylic acids, and aromatic groups. [ABSTRACT FROM AUTHOR]

With the tncreasing production of used cigarette filter (UCF) , its efficient treatment and conversion has become a research hot topic today. This study is aimed to efficient conver­sion of UCF (used cigarette filter) trito value-added chemicals by microwave-assisted depoly­merization method. The liquid product of bio-oil was analyzed by FTIR and GC-MS. The sol­id product of bio-char was characterized by FE-SEM and BET. Results showed that the yield of bio-oil obtained from UCF was 48. 28%. The esters, aromatics, phenols and ethers in bio­oil showed the high selectivity. The selectivity of methyl acetate in bio-oil reached to 53. 86%. UCF bio-char presented high specific surface area (316. 7 m2/g) and mesoporous pore structure(4.24 nm) , whichindicatedthatit hascertaintion, catalysis and electrochemistry.Thisstudy willprovideanew wayforthereductionand high value utilization of UCF. [ABSTRACT FROM AUTHOR]

Copyright of Chemistry & Industry of Forest Products is the property of Chemistry & Industry of Forest Products Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Advances in New & Renewable Energy is the property of Editorial Office of Advances in New & Renewable Energy and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Dual catalyst was prepared with the co-precipitation method and then applied to the research of hydrogen production from steam reforming process of bio-oil. The effects of temperature， S/C ratio (molar ratio of steam to carbon) and weight hourly space velocity on the reaction process were studied. Comparing with the common steam reforming process， the hydrogen yield and volume fraction of the sorption-enhanced steam reforming process of bio-oil for hydrogen production was significantly increased. As both temperature and S/C ratio increased， hydrogen yield and volume fraction of the sorption-enhanced steam reforming process were elevated first and then reduced slightly， and the temperature corresponding to the highest hydrogen yield decreased significantly compared with the common reforming. At 650℃， when the S/C ratio was 4.5， the hydrogen yield reached the peak value of 87.60%， with the hydrogen volume fraction of 94.75%. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Petrochemical Universities / Shiyou Huagong Gaodeng Xuexiao Xuebao is the property of Journal Editorial Department Of Liaoning Shihua University and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

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Copyright of Journal of Xinyang Normal University Natural Science Edition is the property of Journal of Xinyang Normal University Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

生物油轻质组分中水的质量分数高达85%，除水困难，弃之浪费又造成污染.采用水相重整的方法可充分利用这部分物质，得到宝贵的氢气资源.实验室以Pt/Al2O3为催化剂，可得到757 mL的气体，并且氢气的体积分数高达65.86%.由于Pt为贵金属催化剂，研究其在反应过程中的稳定性非常必要.为此，对反应后的催化剂进行了 XRD、TEM、SEM和TPO表征，发现其性质发生了较大的改变.将催化剂煅烧处理后进行重复试验，发现其催化活性和对氢气的选择性均明显下降，即Pt/Al2O3在生物油轻质组分水相重整制氢反应体系中的稳定性较差，难以重复利用.

Bamboo is a typical agricultural and forestry biomass resource in China, which has the advantage of short growth cycle, high yield, abundant reserves. However, biomass has the disadvantages of high water content, high O/C ratio, poor grinding performance and low energy density. Torrefaction is a mild pre-pyrolysis process which operates at normal pressure, inert gas and lower temperature (200 to 300°C). Torrefaction pretreatment can effectively improve the properties of biomass, such as increasing the heating value or energy density, reducing the moisture content and O/C ratio, and improving the grinding and hydrophobicity. By these upgraded properties, the torrefaction pretreatment can also reduce the content of moisture and oxygen-containing compounds in the bio-oil, increase the heating value of bio-oil, and improve the quality and stability of bio-oil. In this paper, bamboo torrefaction was carried out in a furnace with programmed temperature controlling, Thermogravimetric analyzer coupled with Fourier transform infrared spectrometry (TGA–FTIR), pyrolyzer coupled with gas chromatography/mass spectrometer (Py–GC/MS) at different temperatures of 210, 240, 270 and 300°C. Then the effect of torrefaction temperature on the properties of the gas, solid, and liquid products was studied in order to reveal the torrefaction mechanism. The results showed that: (1) When the torrefaction temperature increased, the content of fixed carbon and C in the solid product increased significantly, resulting in an increasing of the calorific value and energy density from 18.85 MJ/kg to 23.12 MJ/kg. The oxygen content was significantly reduced, resulting in a decrease of the O/C ratio from 0.74 to 0.42. (2) Based on the FTIR analysis, the gas composition was mainly composed of H2O, CO2, CO, and CH4, and CO2 was the dominant gas, followed by H2O, CH4 and CO, and all gas content gradually increased as the torrefaction temperature increased; (3) Based on the Py-GC/MS analysis, the liquid products are mainly composed of acids, ketones, furans, phenols, aldehydes and other organic compounds. Acids, phenols and furans were the dominant components with the content of the 20.34%, 22.05% and 31.42% respectively. However, the contents of ketones and aldehydes were relatively lower, which are 10.43% and 8.26%, respectively. As the torrefaction temperature increases, the content of acid increases first and then decreases. The contents of furans, phenols, and ketones increase gradually, and the aldehyde content does not change significantly. (4) Based on the properties of gas, solid, and liquid products, the oxygen in the bamboo was mainly removed in the form of gas components (H2O, CO2 and CO, etc.) and oxygen-containing organic components (acids, phenols and furans, etc.). The torrefaction pretreatment can improve the content of C in the solid product and reduce the oxygen content, thereby increasing the energy density of bamboo. In addition, torrefaction can remove moisture and oxygen-containing compounds in bio-oil, and eventually increase the application value of biomass. This study provides basic data for the energy use of bamboo. [ABSTRACT FROM AUTHOR]

As an ideal clean energy, biomass is friendly to the environment. Bio-oil is a brown and black viscous liquid obtained by rapid pyrolysis of biomass under anoxic conditions. As a kind of liquid fuel, it has the disadvantages of high acid value, high water content, high viscosity and low calorific value. In addition, bio-oil is the mixture of hundreds of chemicals. Carboxylic acids enhance corrosion resistance of bio-oil. Amounts of water reduce the calorific value of the bio-oil. Aldehydes and other labile compounds make the bio-oil coking or polymerize easily during storage, with the increased viscosity, affecting the quality of the bio-oil. In this experiment, in order to reduce the content of carboxylic acid in bio-oil, the carbon-based solid acid catalysts were used to catalyze esterification of bio-oil. In the experiment, 4 kinds of carbon-based solid acid catalysts were prepared by incomplete carbonization and carbonization-sulfonation. They were starch-TsOH, sucrose-TsOH, glucose-TsOH and corn flour-sulfuric acid. The catalysts were characterized by FTIR (Fourier transform infrared spectroscopy), indicating that the carbon-based solid acid catalyst is an aromatic carbon compound with sulfonic groups. Esterification was carried out with acid and alcohol as model compounds. Among the 4 catalysts, starch-TsOH had the highest esterification rate, and the conversion of acetic acid reached 91.58%. The effects of reaction temperature, reaction time, catalyst mass fraction and ratio of alcohol to acid on the conversion of acetic acid were investigated by single factor experiment. Response surface methodology was used to optimize the catalytic esterification conditions of the bio-oil model compound. The optimum reaction conditions were as follows: reaction temperature 100 °C, alkyd ratio 3.37, reaction time 2.49 h, and catalyst mass fraction 5.26%, and the acetic acid conversion rate reached 95.51%. Under these conditions, 3 validation experiments were carried out, the conversion rates were 94.89%, 94.26% and 95.01%, respectively, and the relative deviation was 0.83%, which was very close to the predicted value. This indicated that the model was reliable for the analysis and prediction of the optimum esterification conditions. Under the optimum reaction conditions, the starch-TsOH catalyst was reused 5 times, and the activity of the catalyst was investigated. The results showed that the catalyst was deactivated seriously after 4 times, and the conversion rate of acetic acid was reduced to 52.14%. After esterification of bio-oil with methanol, ethanol and n-butanol, the carboxylic acid was converted into neutral ester, and the acid value was reduced by 82.82%-91.41%. Moreover, after esterification, the density and viscosity of bio-oil decreased obviously, and the calorific value increased. The bio-oil and esterified bio-oil were analyzed by FTIR and GC-MS (gas chromatography - mass spectrometer), which showed that some carboxylic acids in bio-oil were converted into esters, some acetals were produced, and phenols were unchanged basically. So, in the future experiments, we should consider how to make better use of phenolic compounds. After esterification and dehydration of bio-oil, the water content of bio-oil was reduced to 2.5%, and the calorific value was increased. The effect was significant, which indicated the necessity of water separation. [ABSTRACT FROM AUTHOR]

In recent years, the number of fossil fuels is decreasing sharply, and the harmful gases produced by fossil fuel combustion endanger human health and pollute the environment, people are devoted to looking for the alternative fuels of fossil fuels. Biomass energy is a good choice, it is renewable and clean. But the biomass was always burned directly, it is a great waste of biomass sources. In order to reduce the waste of biomass resources and protect the environment, we studied the rapid pyrolysis and catalytic cracking technology to convert the biomass to liquid fuel, which we called the liquid bio-oil. Choosing rape straw as biomass raw materials, HZSM-5 and MCM-41 were used to catalyze the rape straw pyrolysis with different mixing ratios. The experimental instruments include electronic controller, catalytic reactor, pyrolysis reactor, vacuum pump, cold trap, cooling tower, bio-oil collector and connecting pipe. The rape straws were placed in the pyrolysis reactor, the catalysts were replaced in the catalytic reactor, the vacuum pump pressure was controlled at 5kPa and the temperature of the cooling tower was set to -20 ℃. According to the physical and chemical properties, FT-IR and GC-MS analysis results of organic oil and the BET analysis results of catalysts, we studied the effect of HZSM-5 and MCM-41 mixing ratios on the quality of bio-oil. The results showed that with the increase of MCM-41 content, the yield of bio-oil organic phase decreased first and then increased. The density, oxygen content and kinematic viscosity of refined organic oil decreased first and then increased，while carbon content and calorific value increased first and then decreased, when HZSM-5 and MCM-41 were mixed with 1:1, the higher calorific value was 34.31 MJ/kg. The organic phase of refined oil showed six obvious absorption peaks, respectively, they were the absorption peaks of alcohols or phenols, aromatic compounds, acids and aldehydes, ketones, carboxylates, esters and substituted aromatic compounds. The mass fraction of aromatic hydrocarbon increased first and then decreased, while the mass fraction of carbonyl compounds showed the opposite trend, the mass fraction of acids was continuously reduced. With the increase of MCM-41 content, the catalytic activity and absorption capacity of mixed catalysts improved and tended to be stable when the mass fraction of MCM-41 was 50%. From these analysis results, we can speculate the catalytic cracking reaction mechanism of rape straw on HZSM-5 and MCM-41. Because of the large specific surface area and pore size of mesoporous molecular sieve MCM-41, most of the macromolecules in its pore channels can be decomposed into small molecules such as aldehydes, ketones and other small molecules by decarboxylation, dehydroxylation and ring-opening polymerization in the pore channels. These small molecules re-entered the pores of the microporous molecular sieve HZSM-5, and generated aromatic hydrocarbons, H2O, CO2 and CO through the decarbonylation, aromatization and deoxidation, and then the oxygen content in organic phase decreased, aromatic substances content increased, the acidity reduced, so that the quality of bio-oil was improved. This study could provide the experimental basis and the theoretical basis for the efficient utilization of biomass. [ABSTRACT FROM AUTHOR]

In order to upgrade bio-oil through hydrofining under the operating conditions of atmospheric pressure, low temperature and catalyst-free, the technology of non-thermal plasma discharge unit for gas-liquid two-phase were applied. The influence law of operating voltage, gas flow rate, reaction time and other factors on the hyclrodeoxygenation and physicochemical properties of bio-oil were investigated systematically by the self-designed nonthermal plasma discharge device for gas-liquid two-phase. The results showed that with the increase of operating voltage and gas flow rate, the deoxygenation rate and the high calorific value of gas-liquid two-phase discharge hydrofining biological oil first increased and then decreased. With the extension of reaction time, they first increased and then stabilized. Compared with the catalytic pyrolysis and fast pyrolysis bio-oil, the content of alcohols, phenols and ketones in gas-liquid two phase discharge hydrogenation of refined bio-oil were relatively low, and hydrocarbons increased significantly. Refined bio-oil quality was also improved, which confirmed that the feasibility of gas-liquid two phase discharge hydrofining biological oil technical scheme. [ABSTRACT FROM AUTHOR]

采用不同硅铝比的HZSM-5催化剂，在不同条件下（超临界、亚超临界、非超临界乙醇）催化提质生物油中的高沸点组分(HBF)，应用磷核磁共振(31P-NMR)定量检测了提质前后生物油中醇、酚和羧酸类羟基的质量比（羟基质量/生物油质量）变化，研究和评价了催化剂和超临界条件对生物油催化提质的效果.研究表明，超临界条件有利于生物油中脂肪族羟基的转化，但是不利于非缩合羟基的转化；使用不同酸强度的HZSM-5都能使生物油中的羧基完全转化，增加催化剂的酸强度可以促进脂肪族羟基的转化，而只有酸性较弱的催化剂才能顺利转化非缩合酚羟基.

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With Ce-Ni/Co as reforming catalyst and CaO from calcination of calcium acetate as CO2 adsorbent, the sorption-enhanced steam reforming of bio-oil for hydrogen production was studied. The results show that the addition of CO2 sorbent can effectively promote the hydrogen molar fraction and hydrogen yield compared with the case without CO2 sorbent under the same temperature and M (S)/ M (C)ratio (the molar mass of steam to carbon in the model compounds of bio-oil). When the CO2 sorbent existed, the hydrogen molar fraction and yield increased first, then decreased with the increase of the reforming temperature, and reached the maximum at 700°C. With the increase of M (S)/M (C)ratio, the hydrogen molar fraction increased first, then decreased, and was the largest at the M(S)/M(C)ratio of 9, while the hydrogen yield increased till the M(S)/M(C)ratio reached 9, then changed slightly. With the increase of M(CaO)/M (C)ratio (the molar mass of calcium oxide to carbon in the model compounds of bio-oil), the hydrogen molar fraction increased gradually, but changed slightly after the M (CaO)/M (C)ratio reached 3, while the hydrogen yield increased first and then decreased, reached the maximum at the M(CaO)/M(C)ratio of 3. The optimum conditions for steam reforming of bio-oil with CO2 sorption are 700°C, M (S)/M (C)=9 and M (CaO)/M (C)=3 , where the hydrogen molar fraction and the hydrogen yield are 92.2% and 84.1% respectively. [ABSTRACT FROM AUTHOR]