Development of carbon fibers from biomass tars

Transcription

1 Development of carbon fibers from biomass tars WM Qiao a, M Huda a, S-H Yoon a, Y Korai a, I Mochida a, H Hayashi b, K Kawamoto c a Institute for Materials Chemistry and Engineering, Kyushu University Fukuoka , Japan b The Kansai Electric Power Co., Inc. Hyogo , Japan c Kansai Environmental Engineering Center Co., Ltd. Osaka , Japan

2 Background Biomass tar is a by-product in the carbonization, but the most is not utilized. Effective utilization of the biomass tar is indispensable for sequestration of CO 2. Charcoal from biomass is used as fuel, functional charcoal etc. Tar from fossil fuel is the source for functional carbons. Objective Biomass tar was modified through the polymerization of its phenol-containing components to develop biomass tar resin. Carbon materials such as carbon fibers were expected to be developed from the resin as unique precursor.

3 Biomass tar Formaldehyde Experimental Preparation procedure of biomass resin and its derived carbon fibers Mixing 10% Oxalic acid 10% HCl acid 90 o C x 60min 90 o C x 35min Polymerization Removal of H 2 O Biomass resin Spinning Curing Carbonization o C 200 o C o C Carbon fibers

4 Analysis and measurement Biomass tar and its resin: 1 H-NMR for hydrogen distribution of tar FT-IR for oxygen-containing components of tar TG for thermal stability of tar and its resin TOF-MS for molecular weight distribution of tar and its resin GC-MS for determination of components of tar Property measurement of carbon fibers: XRD, Raman, SEM, Mechanical properties (tensile strength and modulus)

5 Results Basic data of wood, bamboo tars and their resins after the polymerization Elemental analysis (wt%) C/O SP C H N O (by diff) ( o C) Wood tar Bamboo tar Wood tar resin Bamboo tar resin Biomass tar contains a lot of oxygen-containing groups

6 1 H-NMR analysis of wood and bamboo tars in CDCl 3 Wood tar Bamboo tar Chemical shift, ppm Chemical shift, ppm Hydrogen distribution, % f a Wood tar Bamboo tar H a H H +H H a :aromatic hydrogen ( 1 H)=6~9ppm; H : -hydrogen ( 1 H)=1.7~4; H : -hydrogen ( 1 H)=1~1.7; H : -hydrogen ( 1 H)=0.5~ Biomass tar shows low aromatic fraction

7 FT-IR spectra of wood and bamboo tars Wood tar Bamboo tar -COOH -OH H 2 O -CHx -CHx -C=O Aromatic -C-O-C- -OH -CHx Bamboo tar contains more oxygen groups, namely phenol-group fraction.

8 Phenol-containing components are polymerized in biomass tar

9 GC-MS spectra Wood tar Bamboo tar Retention time (min)

10 Compound formulas in wood and bamboo tars No RT Compound MW Formula GC peak area, % min Wood tar Bamboo tar furancarboxalfehyde 96 C 5 H 4 O furanmethanol 98 C 5 H 6 O methyl-2-cyclopenten-1-one 96 C 6 H 8 O (2-franyl)-ethanone 110 C 6 H 6 O Butyrolactone 86 C 4 H 6 O methyl cyclopentanone 98 C 6 H 10 O methyl-2-furancarboxalfehyde 110 C 6 H 6 O Tetrahydro-2-furanmethanol 102 C 5 H 10 O methyl-1,2-cyclopentanedione 112 C 6 H 8 O Phenol 94 C 6 H 6 O Methoxy phenol 124 C 7 H 8 O No known Methyl phenol 108 C 7 H 8 O Maltol 126 C 6 H 8 O Methyl phenol 108 C 7 H 8 O Methyl phenol 108 C 7 H 8 O Dimethyl phenol 122 C 8 H 10 O Dimethyl phenol 122 C 8 H 10 O Naphthalene 128 C 10 H methoxy-4-methyl phenol 138 C 8 H 10 O methoxy-4-methyl phenol 138 C 8 H 10 O ethyl phenol 122 C 8 H 10 O Dimethyl phenol 122 C 8 H 10 O ,4:3,6-dianhydro-α-d-glucopyranose ethyl-4-methoxy phenol 152 C 9 H 12 O

11 Benzenediol 110 C 6 H 6 O Benzenediol 110 C 6 H 6 O Methyl-1,2-benzenediol 124 C 7 H 8 O ,6-dimethoxy phenol 154 C 8 H 10 O methoxy-4-propyl phenol 166 C 10 H 14 O Methyl-1,2-benzenediol 124 C 7 H 8 O hydroxy-3-methoxy benzoic acid 168 C 8 H 8 O methoxy-4-(1-propenyl)-phenol 164 C 10 H 12 O (4-hydroxy-4-methoxyphenyl)-ethanone 166 C 9 H 10 O (2,6-dihydroxy-4-methoxyphenyl)-ethanone 182 C 9 H 10 O (4-hydroxy-3-methoxyphenyl)-2-propanone 180 C 10 H 12 O ,4-dihydroxy-3-methyl propiophenone 180 C 10 H 12 O ,6-dimethoxy-4-(2-propeny)-phenol 194 C 11 H 14 O No known ,6-dimethoxy-4-(2-propeny)-phenol 194 C 11 H 14 O No known No known No known (5α,9α,10β)-kaur-15-ene 272 C 20 H (1,1-dimethylethyl)-anthrancene 234 C 18 H No known C 20 H 30 O C 21 H 30 O Other peak area, % Peak area of phenol-containing group, %

12 Carbon fibers with smooth surface, diameter: 15~20 µm

13 Properties of carbon fibers derived from tar resins Fiber Curing conditions Curing yield* Carbonization conditions Carbonization yield** d 002 R o C-h- o C/h % o C-h- o C/min % nm (I 1350 /I 1580 ) Bamboo tar resin Wood tar resin Yield base:*resin; **cured resin

14 Mechanical properties of carbon fibers derived from bamboo and wood tar resins Precursor Carbonization Diameter of fiber Tensile modulus Tensile strength o C µm GPa MPa Bamboo tar resin Wood tar resin Phenol resin* *Kynol carbon fiber derived from phenol resin

15 Conclusions 1. Biomass tar contains a lot of phenol-group compounds. The components can be polymerized into a thermol-setting resin, which is confirmed a useful precursor to develop high performance carbon materials. 2. Carbon fibers (10~20 µm in diameter) have been successfully prepared through spinning, curing and carbonization from biomass tar resins. Their properties (tensile strength of 250~630 MPa and tensile modulus of 27~44 GPa) are comparable to those of commercial isotropic carbon fibers. 3. Activated carbon fibers can be derived.