精煉度與孟宗竹炭特性之關係

Relationship between Degree of Refining and Characteristics of Moso Bamboo Charcoals

葉民權(Min-Chyuan Yeh) ； 邱郁惠(Yu-Hui Chiu) ； 謝惠貞(Hui-Jen Hsieh) ； 潘靖淳(Jing-Chun Pan)

《林產工業》 25卷2期 (2006/06) Pp. 123-132

摘要

本研究利用鹿谷地區4～5年生之孟宗竹以土窯燒製竹炭，依不同方式進行電阻測定檢測竹炭之精煉度，並將竹炭區分為表、中、內三層，探討不同精煉度竹炭之基本性質。結果顯示燒製溫度500℃條件下其精煉度為7，碳含量為81.96%，氣乾時之電阻係數較絕乾者低。600℃條件下精煉度為3，碳含量84.93%，氣乾與絕乾條件之電阻係數並無差別。尺寸較大竹炭有較低之電阻係數，50x120mm竹炭之電阻係數約為30x30 mm竹炭之76%。由於竹炭電阻值變異大，在炭材內外層表面及各切面測定之電阻係數均無差別，垂直與平行織維方向之條件亦無顯著差別。以毫歐姆電阻錶測得之值約為三用電錶之11.6%。精煉度為3之孟宗竹炭其中層之炭材BET比表面積遠較外層及內層為高，可達282.67g/m2，且微孔表面積佔95.4%為最高，屬鹼性竹炭，其各層平均密度為1.672g/cm3的。精煉度為7之竹炭為偏酸性，各層平均真密度為1.543 g/cm3，與精煉度3之竹炭其莫氏硬度均介於3～4而不易區分。

關鍵字

孟宗竹 ； 竹炭 ； 土窯 ； 比表面積

並列摘要

Bamboo charcoal was produced using muddy kiln with 3-4 year old Moso bamboos from Lu-Gu region as materials in the study. The degree of refining of bamboo charcoal were estimated based on the electric resistivity measured with different ways and instmments. The basic properties of bamboo charcoal with different refinement were then investigated by dividing bamboo culm into inner, middle, and outer layers. The resulted degree of refining of 7 was obtained for the bamboo charcoal produced at 500°C having 81.96% of carbon content and lower electric resistivity in air-dried condition than that in kiln-dried condition. While the bamboo charcoal produced at 600°C was classified as degree of refining of 3 having 84.93% of carbon content and showed the similar electric resistivity both in air-dried and kiln-dried condition. Larger specimens had lower electric resistivity, i.e., the electric resistivity measured from 50x120 mm bamboo charcoal was 76% of measured from 30x30 mm specimen. There was no significant difference of electric resistivity measured from outer, inner surface, and other cutting faces of bamboo charcoal products due to large variation. The values of electric resistivity measured along and across the grain of bamboo charcoal also showed no significant difference. The value of electric resistivity measured with more accurate instruments was only 11.6% of that with more convenient multi-meters. BET specific surface area measured from middle layer of bamboo charcoal with degree of refining of 3 was 282.67 g/cm2 which was higher than those of outer and inner layers, and had highest micropore surface area. The bamboo charcoal with degree of refining of 3 is alkaline and 1.672 g/cm3 for average physical density of each layer, while the charcoal with refinement of 7 is acid and 1.543 g/cm3 for average tme density. Both degree of refining of 3 and 7 bamboo charcoal had Mohs hardness between 3-4, which is difficult to distinguish.

並列關鍵字

Moso bamboo ； Bamboocharcoal ； Muddy kiln ； Specific surface area