記述言語：英語   出版者・発行元：AMER CHEMICAL SOC  

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掲載種別：研究論文（学術雑誌）   出版者・発行元：American Chemical Society (ACS)  

DOI： 10.1021/ie501811x

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：ELSEVIER SCIENCE SA  

Biomass is getting notable as a new energy resource to replace fossil resources and to restrain CO2 emission recently. However, it is obvious that the energy use of biomass is unsuitable for its limit of available amounts. Consequently, we investigated the possibility of new refinery scheme of biomass to utilize biomass as an alternative raw material to fossil resources with suggested two-step treatment method. We oxidized cellulose and biomass with H2O2 first and put the residue into hydrothermal condition to obtain some specific chemicals. Through the first oxidation of cellulose, 0.26 g/g-cellulose of organic acid was obtained, and 0.35 g/g-cellulose of oxalic acid was obtained under the catalytic condition. Both cedar and cellulose decreased their crystallinity through the first oxidation and increased their reactivity, we could obtain hydroxymethylfurfural(HMF) from cellulose and biomass through the hydrothermal degradation, 0.11 g/g-cellulose and 0.12 g/g-cedar respectively.

DOI： 10.1016/j.cej.2013.08.055

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：WALTER DE GRUYTER GMBH  

An effective hydrolysis method for recovering oligosaccharides directly from lignocellulosic biomass has been investigated. Formic acid was selected as a hydrolysis reagent, due to its high acidity in organic acids. The degrees of cellulose hydrolysis and lignin elution were determined by the combination of the reaction temperature and formic acid aqueous solution concentration. We successfully obtained approximately 47 wt% of oligosaccharides, keeping the minimum lignin elution at 150 degrees C and with 25 vol% formic acid aqueous solution concentration. Such a high yield of oligosaccharides was due to the relaxation of biomass structure. Furthermore, by diluting the formic acid aqueous solution concentration, or evaporating the solution, lignin can be separated from the oligosaccharides completely as deposits. Finally, two options for the efficient recovery of saccharides have been proposed.

DOI： 10.1515/gps-2012-0090

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記述言語：英語   出版者・発行元：AMER CHEMICAL SOC  

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：AMER CHEMICAL SOC  

There has been a great interest in converting lignin into chemicals, but lignin is not used as feedstock for chemical production at present. Considering the rigid structure of lignin, we have developed a new method to recover chemicals from lignin under severe conditions. This method is the hydrothermal oxidative degradation using 0.1% hydrogen peroxide solution in the flow reactor at 150-200 degrees C. When alkali lignin was oxidized for 2 min at 200 degrees C, the total yield of organic acids was as large as 0.45 g/g-lignin. The organic acids consisted of formic, acetic, and succinic acids, and the high-molecular-weight lignin also remained after the oxidation. On the other hand, when organosolv lignin was oxidized at 160 degrees C, lignin molecules were depolymerized into the oligomer of M-W = ca. 300 and the total yield of organic acids was 0.20 g/g-lignin. The product distribution depended on the difference in the structures between the two lignin samples. It was clarified that the proposed method is valid to produce valuable chemicals from any kind of lignin.

DOI： 10.1021/ef101477d

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：ELSEVIER SCI LTD  

A kinetic analysis of the pyrolysis of various types of biomass (trunk, bark, leaf, shell, herbage, food dregs, and polysaccharide) as well as synthetic biomass consisting of cellulose and lignin was performed using thermogravimetric analysis data. The reaction rates of biomass pyrolysis were found to be expressed simply by a single nth-order reaction model. The kinetic parameters (frequency factor k(0), activation energy E, and reaction order n) were estimated first by differentiating the thermogravimetric curves and then by the nonlinear estimation method. The rate parameters of the pyrolysis of both 38 biomass samples and 9 synthetic biomass samples were successfully correlated in terms of the solid residue yield omega; charts are presented showing the correlations. Furthermore, a linear correlation was found between omega and the lignin content L in the woody biomass. This allows the kinetic parameters of biomass pyrolysis to be estimated using the value of omega, which is obtained from thermogravimetric measurements or estimated from the value of L for the biomass feedstock. (C) 2010 Elsevier Ltd. All rights reserved.

DOI： 10.1016/j.fuel.2010.08.023

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：AMER CHEMICAL SOC  

Primary tars produced from gas treatment in a low-temperature region were confirmed by thermogravimetric analysis of tar-mixed biomass that they would be easily handled by using simple reforming methods. A two-stage reactor was used to investigate the secondary reaction of light tar decomposition. The effect of air on light tar decomposition showed that gas products increased when the upper temperature was increased from 600 to 900 degrees C. When biomass char pyrolyzed to 900 degrees C was loaded in the upper reactor, the decomposition of light tar under inert atmosphere occurred by steam reforming to produce fuel gases even at a low temperature of 600 degrees C. When the upper temperature was increased to 800-900 degrees C, the yield of light tar significantly decreased and became almost zero because steam reforming and related reactions could proceed to produce CO and CO(2) even in the case without biomass char. However, CO could be selectively obtained at the highest yield of 24.0 wt % because of the effect of catalytic char at a high temperature of 900 degrees C. Finally, alternative methods of light tar reforming are discussed for the development of a biomass gasification process to obtain tar-free gaseous products and/or valuable chemicals.

DOI： 10.1021/ie901695r

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記述言語：日本語   出版者・発行元：公益社団法人 化学工学会  

DOI： 10.11491/scej.2010f.0.112.0

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：AMER CHEMICAL SOC  

The analyses of structure change during pyrolysis of cellulose at different heating rates were investigated to clarify the existent behavior of the cross-linking reaction. For Structural analyses of cellulose precursors, FTIR spectra and XRD patterns confirmed that the dehydration reaction to produce water and cross-liked precursor Simultaneously Occurred with the glycosidic reaction to produce tar during pyrolysis. on the basis of the assumptions that hydroxyl groups in cellulose converted to water,a new parameter index, so-called the degree of dehydration during pyrolysis, X-p, including its distribution in char (X-c) and tar (X-t), was determined. For the cross-linking analyses at low healing rate, cross-linking reaction may occur until approximately 360 degrees C where X-c reached its maximum,while the cross-linked tar seems to be released above 360 degrees C. For tar analyses, cross-linked dinner can be observed for slow pyrolysis, whereas tar products obtained by flash pyrolysis showed relatively higher yield in cellobiosan with no cross-linked volatiles. Finally, based on previous kinetic models, the modified pathway of cellulose pyrolysis was proposed by considering the proposed parameter related to the dehydration.

DOI： 10.1021/ef900674b

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：AMER CHEMICAL SOC  

Treatment of biomass in nitrogen and air at 240-340 degrees C was conducted in order to examine the low-temperature region in a downdraft gasifier by analyzing the treated precursors and product distribution, Gas-treated precursors were then pyrolyzed in flash mode at 764 degrees C for further analysis. Overall, the tar yield decreased from approximately 50 wt % to less than 20 wt % upon oxidation of the sample at a very low heating rate to 260-300 degrees C in air. Moreover, tar evolution was almost completely suppressed during the subsequent flash pyrolysis. This indicates that the structure of the treated precursors was gradually changed to suppress tar release through cross-linking reactions and partial oxidation. From elemental analysis of the precursors treated with air, it was also estimated that dehydration and partial oxidation proceeded simultaneously. The results indicate that the release of tar products such as dimers call be partially suppressed by air treatment at low temperature.

DOI： 10.1021/ie900264n

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記述言語：日本語   出版者・発行元：公益社団法人 化学工学会  

DOI： 10.11491/scej.2009.0.499.0

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：ELSEVIER SCI LTD  

A shaft kiln is considered to be a promising pyrolysis device for the efficient decomposition of municipal wastes. In this device, the temperature distributions of the gas and solid phases can be separately controlled, thereby leading to considerably different profiles for both the phases. The temperature controllability in a shaft kiln helps us to obtain a suitable profile of the gas-phase temperature for the decomposition of tar that evolves from the solid phase. By leveraging this advantage of the shaft kiln, we performed further pyrolysis and steam reforming of the volatiles formed from the pyrolysis of biomass and several polymers using a two-stage reactor that was maintained at different temperatures. The amount of tar decreased with an increase in the temperature in the upper reactor in the absence of a catalyst. By using the experimental results, we developed a lumped kinetic model for secondary gas-phase reactions and performed a kinetic analysis of the reactions that proceeded in the upper reactor. It is confirmed that the simulation model is successful in reproducing the product distribution of the gas-phase reactions of volatiles from biomass and polymers. (C) 2008 Elsevier Ltd. All rights reserved.

DOI： 10.1016/j.fuel.2008.04.005

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：AMER CHEMICAL SOC  

Pretreatment of cellulose with acid and hot water at low temperature (200-260 degrees C) was performed to control the pyrolysis products by changing the precursor structure. Acid pretreatment changed cellulose into a partly cross-linked and loose structure, which resulted in a large amount of tar consisting of levoglucosan and high-molecular weight components by flash pyrolysis. On the contrary, hot water treatment caused the suppression of tar formation by imparting a random and highly cross-linked structure to the cellulose precursor. A new parameter index, referred to as the degree of cross-linking for pretreated precursors, X(0), which is based on glucose and oligosaccharide yields produced from acid hydrolysis of pretreated samples, was proposed to analyze the precursor structure. As the degree of cross-linking increased with the severity of the pretreatment conditions, the number of OH groups in the pretreated samples decreased. Through analysis of the solid precursors using this index, a simple structural model was proposed to properly estimate the distribution of the pyrolysis products. The estimated values were in agreement with the product yields experimentally obtained by flash pyrolysis.

DOI： 10.1021/ie800080u

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：ELSEVIER SCI LTD  

We propose a novel method for preparing iron-dispersed carbonaceous materials by utilizing low-grade materials and waste heat. Iron is loaded into the biomass through stirring it in a solution of FeCl2 for 2 h and then pyrolyzed at 600-900 degrees C to prepare materials composed of iron and carbon. Further in order to investigate the reactivity of the sample, steam and CO2 gasifications of the material was performed at 800-900 degrees C. Approximately 80% of the carbon in the biomass remained in the solid state during pyrolysis at 600 degrees C because of the effect of FeCl2 in promoting the carbonization of the biomass. The prepared material displayed high reactivity during gasification due to the catalytic effect of loaded iron. This result indicated the possibility that the composite may be used as an iron and heat source for a steel converter. Furthermore, the high reactivity of the composite during steam gasification suggests its usefulness as a medium for hydrogen or carbon monoxide production. (C) 2007 Elsevier Ltd. All rights reserved.

DOI： 10.1016/j.fuel.2007.12.013

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記述言語：日本語   掲載種別：研究論文（学術雑誌）  

A new method has been presented by which the contents and elemental composition of biomass and plastics in the wastes is quantitatively determined. A new two-stage pyrolyzer was proposed to determine simply the contents of biomass and each plastic from the gas analysis during the pyrolysis of mixture under no interaction state. It was found that the contents of polyethylene, polypropylene, polystyrene, and biomass is determined from the ethane, propylene, C4 compounds, and CO2 yields, respectively. Next, a new method has been proposed to determine the elemental composition of each component by combining CHO diagram and the calorimetric value of the mixture. The estimated values were coincided with the real values within 10 % error. Thus, it was clarified the proposed method is valid for estimating the quality of waste materials to stably operate the treatment process of wastes such as combustion, pyrolysis, gasification etc.

DOI： 10.3775/jie.87.519

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：SOC CHEMICAL ENG JAPAN  

Pyrolysis or Douglas fir with metal compounds has been carried out to examine the effect of metal compounds oil the pyrolysis profiles. The profiles dramatically shifted into lower or higher temperatures by adding some metal compounds. On the other hand, the presence of metal chlorides promoted file decomposition of Douglas fir, at low temperature. The metal compounds having high hydrophilicity, by Douglas fir decomposition was shifted toward lower temperatures, caused all increase in char and a decrease in tar through promoting the cross-linking reaction at low temperature. From these results. it call be said that the control of dehydration at low, temperature is an essential Factor to achieve high char Yield with minimizing tar formation.

DOI： 10.1252/jcej.07we275

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：SOC CHEMICAL ENG JAPAN  

Pyrolysis of NaOH-loaded Douglas fir and cellulose has been carried out to determine the effect of sodium hydroxide on the pyrolysis profile. A tar yield of 0 wt% and the char yield of 32 wt% were obtained at a final pyrolysis temperature of 500 degrees C. It was revealed that the amount of hydroxyl groups in the residue significantly decreased at 200 degrees C and that the structure of cellulose was distorted via crosslinking at the same temperature through spectroscopic analyses and diffraction patterns. The crosslinking led to the increase in char yield al 500 degrees C. A detailed analysis showed that char Yield from cellulose at 500 degrees C correlaled linearly with the degree of cross-linking calculated From the amount of dehydration at 200 degrees C. These results showed a possibility that the pyrolysis profile of biomass may be controlled through;in appropriate pretreatment to change the structure of the intermediate.

DOI： 10.1252/jcej.07we262

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：ELSEVIER SCI LTD  

Carbonaceous material produced from municipal waste (MW) was studied as a potential substitute for coal energy by evaluating its calorific values, chlorine content, and combustion behavior. The behaviors of calorific values and chlorine content of carbonized MWs (CMWs) during carbonization were investigated to replace the coal CMWs in the supply material of the existing boilers. By comparing the combustion behaviors of the CMWs and coals with various fuel ratios (=fixed carbon/volatile matter), the overall conversions of the combustion of the CMWs and coals were arranged in the order of their fuel ratios. Therefore, it was possible to evaluate their combustion behaviors using the fuel ratios for practical applications. However, strictly speaking, the detailed combustion behavior of the CMWs was different. A detailed investigation of the combustion process revealed that the combustion of fixed carbon at the burnout of the CMWs was slightly slower than that of the coals for the same fuel ratio, while the initial combustion process including the devolatilization of the CMWs was faster. This behavior was considered to be caused by complicated phenomena such as the catalytic effect on the gasification behavior of alkali and alkali earth metals, hindrance effect of ash on gasification reactant, original chemical structure, and transition of pore structure. (c) 2006 Elsevier Ltd. All rights reserved.

DOI： 10.1016/j.fuel.2006.06.008

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記述言語：日本語   出版者・発行元：公益社団法人 化学工学会  

DOI： 10.11491/scej.2007.0.152.0

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記述言語：英語  

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記述言語：日本語   出版者・発行元：一般社団法人日本エネルギー学会  

A method for predicting the yields of products and the elemental composition of char during pyrolysis of biomass was presented. 10 kinds of biomass feedstocks with a focus on wood biomass were pyrolyzed at various temperatures using a Curie-Point Pyrolyzer attached to a gas chromatograph. At moderate temperature not lower than 485℃, the yields of total volatiles linearly increased with the atomic ratio H/C which was also correlated with the lignin content in feedstock. Furthermore, it was clarified that the average elemental composition of total volatiles produced at these temperatures was equal to that of cellulose and that the tar fraction among volatiles consisted of glucosan or cellobiosan, the molecular weight of which was about 300. By combining these results, we developed a new chart for predicting the elemental composition of char pyrolyzed at moderate temperature only from the elemental analysis of feedstock. The presented method is expected to provide a useful guideline for the decision on pyrolysis condition or subsequent conversion such as gasification and combustion.

DOI： 10.3775/jie.84.46

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記述言語：日本語   出版者・発行元：公益社団法人 化学工学会  

DOI： 10.11491/scej.2005.0.658.0

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記述言語：英語  

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記述言語：日本語   出版者・発行元：公益社団法人 化学工学会  

DOI： 10.11491/scej.2005.0.642.0

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：ELSEVIER SCIENCE SA  

We fabricated two new types of multi-stage micromixers, YM-1 and YM-2. In these devices, mixing is achieved through the repeated splitting and recombination of the fluid flow. It was shown that the two types of micromixers presented here were capable to produce soap free emulsions at short contact times. From the investigation of the effects of the device wall material, the number of stages, etc. on the size of the droplets in the resulting emulsion, it was clarified that the emulsion was formed through efficient mixing achieved by utilizing the interactions which uniquely occur in microspaces, particularly between the device wall and fluid flow. The attained maximum production rates of emulsion in experiments were 5 1/h for YM-1 and 20 1/h for YM-2, respectively. To show the applicability of the mixers to other purposes, rapid extraction of phenol from dodecane by water was also conducted. It was found that YM-1 has a potential to continuously extract phenol even at extremely high flow rates (mixing times within I s). These results show that, although the mixers are extremely small, they have the capability to be used in fairly large-scale industrial plants. (C) 2004 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.cej.2003.10.011

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：AMER CHEMICAL SOC  

New pretreatment methods were developed for separating hemicellulose, cellulose, and lignin from biomass for their efficient use in the thermo-chemical conversion of each component. One method is basically a two-step process. Biomass treated in hot water at 180 degreesC was extracted in a flowing stream of water/acetone mixture under 10 MPa at 230 degreesC. Through the hot water treatment, hemicellulose in biomass was successfully recovered as saccharides, leaving lignin and cellulose as a solid. Through the sequential extraction by the water/acetone solvent, lignin was depolymerized into the water/acetone-soluble compounds and the residual cellulose was partly dehydrated. The other method is a one-step process, in which biomass was directly extracted in 50% water/acetone solution at 200 degreesC using a batch reactor, and the residue was pure cellulose. The proposed methods were expected to be new routes for converting low-grade resources into valuable chemicals.

DOI： 10.1021/ef030148e

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記述言語：日本語   出版者・発行元：公益社団法人 化学工学会  

DOI： 10.11491/scej.2003f.0.309.0

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：AMER CHEMICAL SOC  

Recently, the authors have presented a new method to estimate the strength distribution of hydrogen bonds (HBD) in coal. The method analyzes the IR spectra ranging from 2400 to 3700 cm(-1) that are obtained using an in-situ diffuse reflectance IR Fourier transform (DR) technique with neat, undiluted coal samples. Each spectrum was divided into six hydrogen bonded absorption bands by a curve-resolving method; then the amount of hydroxyls contributing to each hydrogen bond was estimated by Beer's law with different absorptivity for each band. The strength of each hydrogen bond was estimated using a relation presented by Drago et al. that is known as one of the "linear enthalpy-spectroscopic shift relations". In this paper, the method was applied to estimate the hydrogen bond strength distributions formed between coal and several polar solvents: acetone, ethyl acetate, THF, DMF, and pyridine. The enthalpies accompanying the adsorption or desorption of the solvents, which correspond to the heats of adsorption, were also estimated from the HBDs. Only IR spectra measurements were found to be enough to obtain such enthalpies. This greatly simplified the calculation procedure and increased the accuracy of the enthalpies. The validity of the proposed in situ IR measurement method and the analysis method for obtaining HBD was well clarified by comparing the enthalpies obtained in this work with the heats of adsorption and the hydrogen bond formation enthalpies proposed by Arnett et al.

DOI： 10.1021/ef0101457

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：AMER CHEMICAL SOC  

A new oddative degradation method was developed for separating hemicellulose, cellulose, and lignin from an oil palm shell waste, and for converting them into valuable chemicals. The method is basically a two-step process in which the shell pretreated in hot water at 180 degreesC was oxidized with 30%-H2O2 at 60 degreesC (first-stage oxidation) under ambient pressure with or without an Fe catalyst. To increase the product yield and selectivity, a second-stage oxidation of the water-soluble components obtained from the first-stage oxidation was also performed in the presence of the Fenton reagent at 25 degreesC. Through the hot water treatment, hemicellulose in the palm oil shell was successfully recovered as saccharides, leaving lignin and cellulose. Through the first-stage oxidation without the Fe catalyst lignin was converted to water-soluble compounds containing small molecular weight fatty acids such as HCOOH and CH3COOH, and almost pure cellulose was recovered in 22% of yield on carbon basis. After the second-stage oxidation, the yield of small molecular weight fatty acids reached 30 wt % on the oil palm shell basis. The proposed method was expected to be a new route for converting low grade resources into valuable chemicals.

DOI： 10.1021/ef000091l

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記述言語：日本語  

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記述言語：英語  

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記述言語：日本語   出版者・発行元：公益社団法人 化学工学会  

DOI： 10.11491/scej.2007.0.150.0

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記述言語：英語  

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記述言語：日本語  

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記述言語：日本語   出版者・発行元：エネルギー・資源学会  

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記述言語：日本語   出版者・発行元：化学工業社  

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