Pore structures and ethylene adsorption behavior of polysaccharide-derived carbons

CARBON

5 0 ( 2 0 1 2 ) 7 3 7 –7 3 9

Available at www.sciencedirect.com

journal homepage: www.elsevier.com/locate/carbon

Tanso 249 Abstracts Intercalation of sodium into graphite-like layered material BC2N

TANSO 2011 (No. 249), 168–173

Kaoru Yamadaa, Akihiro Kurasakia, Masayuki Kawaguchia,b a

Graduate School of Engineering, Osaka Electro-Communication

doi:10.1016/j.carbon.2011.08.062

University b

Fundamental

Electronics

Research

Institute,

Osaka

Electro-

Communication University

Carbon fiber & composite material – Landscape Germany Wilhelm Frohs, Hubert Jaeger

Graphite-like layered material of composition BC2N was prepared by the CVD reaction of acetonitrile with boron trichloride at 2070 K. Sodium was intercalated into the BC2N film and powder by two methods: a vapor phase reaction and an electrochemical method. The first stage compounds were prepared by the vapor phase reaction using the BC2N film and powder. A mixture of the first and the second stage compounds was prepared from the BC2N powder, while the first stage compound was prepared from the BC2N film by the electrochemical method. The d-spacing of the intercalated layers was 0.43 nm, calculated from the sharp (0 0 1) and (0 0 2) diffraction lines observed on the X-ray diffraction patterns of the first stage compounds prepared from the BC2N films by the two methods. TANSO 2011 (No. 249), 161–167 doi:10.1016/j.carbon.2011.08.061

SGL CARBON GmbH The commercialization of carbon fibers and their composites initially served the defence and aerospace industry. Sporting goods followed and allowed carbon fiber companies to survive the years after the cold war. High prices and manual production technologies hindered entrance into big consumer markets. This situation is going to change with the implementation of highly automated textile processes for the production of carbon fiber reinforced polymers (CFRP). The biggest impetus is coming from the energy and CO2 debate. Thus CFRP components will further grow in the aviation industry but also spread into automobiles, windmills, civil engineering and other industrial applications. The carbon fiber market is dominated by producers based in Japan and in the USA, with precursor production in the hands of Japanese companies. Europe has failed to build home-based precursor and carbon fiber production technologies. SGL Group – The Carbon Company as a leader in the carbon and graphite

Measurement of the dimension changes of carbon artifacts

industry recognized this situation and started to expand its com-

during graphitization in a pilot LWG furnace

petence in carbon fiber and related technology. This includes its

Raymond Perruchouda, Werner Fischera, Italo Letiziab

own precursor production as well as downstream processes like

a

R&D Carbon Ltd.

textile techniques and CFRP components. These activities are

b

Letizia Associates A pilot lengthwise graphitization (LWG) furnace designed and

operated by R&D Carbon Ltd. is a high temperature/pressure dilatometer. The equipment is suitable either for research purposes or for checking industrial baked carbon artifacts (electrodes/cath-

embedded in an industrial and scientific network which has its centre in the south of Germany. SGL’s strategy is to become a European/German home-based key player in carbon fiber and composite technology. TANSO 2011 (No. 249), 174–178 doi:10.1016/j.carbon.2011.08.063

odes) which have to resist the thermal stress created in the full size LWG process. Unlike conventional high temperature dilatometers, this equipment offers the possibility to test cylindrical specimens of large size (Ø50  500 mm) and under pressure.

Pore structures and ethylene adsorption behavior of polysac-

This pilot testing provides useful information for the optimiza-

charide-derived carbons

tion of the power profile in industrial furnaces aiming to maxi-

Naoya Miyajimaa, Koji Hirookaa, Hideto Sakanea,

mize the productivity and minimizing the scrap rate of the end

Masako Furuyab, Kaoru Tamurab, Yorioki Matsumotob

products.

doi:10.1016/S0008-6223(11)00707-X

738 a

CARBON

5 0 ( 2 0 1 2 ) 7 3 7 –7 3 9

Interdisciplinary Graduate School of Medicine and Engineering,

a

Department of Chemical Science and Engineering, Tokyo National

University of Yamanashi

College of Technology

b

b

Matsumoto Giken Co.

Department of Electrical Engineering, Tokyo National College of

Technology Changes of the pore structures in the carbonization process of

c

Kyoto Plant, SEC Carbon Ltd.

two kinds of polysaccharides, cellulose and starch, were investigated in connection with their ethylene adsorption behavior. Both

The effect of electrolysis temperature on the resistivity change of

polysaccharides showed a large weight loss at around 400 °C

cathode graphite during and after electrolysis of alumina molten salt

during pyrolysis. Thereafter, micropores were developed at

was investigated. The resistivity decreased along with electrolysis

500–700 °C where carbon micro-textures are formed with the

and increased after the electrolysis ended. For electrolysis at 910

elimination of light gases. N2 adsorption at 196 °C could not cor-

and 920 °C, q/q0, the resistivity normalized by the original value,

rectly evaluate the micropores because of a temperature kinetic

decreased to 0.80 at first and then showed a plateau at q/q0  0.40

effect on the adsorption, while CO2 adsorption at 25 °C was suc-

during electrolysis. On the other hand, for electrolysis at 950 and

cessful. The uptake amount of ethylene can be predicted from

980 °C, only a plateau at q/q0  0.80 was observed. Formation of the

the micropore surface area calculated from CO2 adsorption. The

stage 8 sodium–graphite intercalation compounds was confirmed

polysaccharides used in this study showed excellent ethylene

for the phase with q/q0  0.40, in contrast to the random stage struc-

adsorption after a simple carbonization treatment without car-

ture for the phase with q/q0  0.80. The SEM-EDX measurement of the

bon-surface modification such as activation or a catalyst support.

phase with q/q0  0.40 showed that sodium was detected not only in

TANSO 2011 (No. 249), 179–184

the vicinity of the surface but also the inner part of the cathode. The signal intensity of sodium was almost uniform in the cross section of

doi:10.1016/j.carbon.2011.08.064

cathode, indicative of sodium intercalation all over the graphite. The cathode was continuously kept at the electrolysis temperature for long time after interruption of electrolysis current until the resistivity

Evaluation of organic vapor breakthrough time of an activated carbon bed containing moisture by Wood’s estimation model

showed a steady value. The resistivity determined after cooling to room temperature was larger than that before electrolysis. TANSO 2011 (No. 249), 191–194

using the Wheeler-Jonas equation Hironobu Abiko

doi:10.1016/j.carbon.2011.08.066

Work Environment Research Group, National Institute of Occupational Safety and Health (JNIOSH), Japan The breakthrough time estimation model reported by Wood makes use of the Wheeler-Jonas equation, the Dubinin-Radushkevich equation and previous research progress regarding gaseous

Relation

of

crystallinity and

orientation

function

to

the

magnetoresistance of carbon materials Yoshihiro Hishiyamaa, Yutaka Kaburagib, Michio Inagakic

adsorption of compact activated carbon beds. The estimation

a

model can take into account the effects of temperature and rela-

b

Faculty of Engineering, Tokyo City University

tive humidity in the environments of activated carbon beds and

c

Professor Emeritus Hokkaido University

Professor Emeritus Tokyo City University

type of organic vapor as adsorbates. In using the model, the determination of several constants or coefficients of its equations is

The relation of crystallinity and preferred orientation parame-

important, and Wood also reported several empirical formulas

ters to the magnetoresistance of carbon materials was examined.

for the constants or coefficients. In this study, we carried out an

We derived the parameters for carbon samples having a planar ori-

estimation of the breakthrough time by the model, and examined

entation with the electric current flowing along the direction per-

problems regarding its empirical formulas and its effectiveness

pendicular to the orientation symmetry axis and for those

with reference to the experimental data of breakthrough times.

having an axial orientation along the direction parallel to the ori-

In particular, the determination of affinity coefficient of organic

entation symmetry axis. On the basis of the magnetoresistance

vapor bOV is most significant in the model. The values of bOV calcu-

data on carbon materials, including pyrolytic carbons, carbon

lated by the empirical formula presented by Wood are liable to be

films, cokes, carbon fibers, etc., the formulae of orientation func-

small for application of recent activated carbon products for gas

tions for planar and axial orientations were derived. The I3/I1 value

adsorption or gas respirators in Japan, and the formula requires

derived from the orientation function is proposed as the parame-

further improvement for exact estimation by the model.

ter for preferred orientation in carbon materials, which changes

TANSO 2011 (No. 249), 185–190

in the range 0–2/3 for the planar orientation, 2/3 for random and point orientations and in the range 2/3–1 for the axial orientation

doi:10.1016/j.carbon.2011.08.065

The parameter ðDq=q0 Þcr shows a good correspondence to interlayer spacing d002 for all carbon materials used, which is useful to differentiate the crystallinity of highly graphitized materials.

Electrical resistivity change of cathode graphite during electrolysis in alumina molten salt – Effect of electrolysis temperature Noboru Akuzawaa, Tomohiro Komodaa, Koji Tamadab, c

c

Takahiro Hirayama , Hiroshi Imagawa

TANSO 2011 (No. 249), 195–212 doi:10.1016/j.carbon.2011.08.067