| Summary: | 碩士 === 國立屏東科技大學 === 森林系 === 91 === Abstract
This paper reports the quality of charcoal and activated carbon manufactured from 3 to 5 years old Moso bamboo (Phyllostachys heterocycla). Upon harvesting, bamboo stems were separated into basal sections (ground level to 2.5 m), mid sections (2.5 m to 4.9 m) and top sections (4.9 m to 7.3 m). Sections from different heights were further cut into 60 cm segments, followed by adjusting the materials into three moisture content regimes, above 60%, between 30% and 60%, and below 30%. Charcoalization was done at 500 ℃, 700 ℃, and 900 ℃, and the charcoal was analyzed for yield, shrinkage, ash content, pH, equilibrium moisture content (EMC), DC resistivity, and Methyl Blue Number. The charcoal obtained from the mid sections at below 30% moisture content was selected to manufacture activated carbon. Activation was done between 500 oC and 1100 oC with holding times between 30 minutes and 180 minutes and CO2 flow rates between 100 ml/min. to 300 ml/min. Activated carbon was analyzed for Methyl Blue Number, Brunauer-Emmett-Teller (BET) surface area, and pore surface area, and pore volume.
Results indicate that charcoal yield, EMC, and DC resistivity decreased with increasing charcoalization temperature and that ash content, pH, and radial and thickness shrinkage increased with increasing charcoalization temperature. Ash content, Methyl Blue Number, DC resistivity, pH, and radial and thickness shrinkage increased while charcoal yield decreased with increasing moisture content of the material during charcoalization. With the exception of a significant less radial and thickness shrinkage with the basal material, other charcoal quality was not affected by stem height of the material. It is concluded that the best charcoalization conditions for Moso bamboo were above 60% moisture content and 700 ℃. Under these charcoalization conditions, the charcoal had a significantly higher Methyl Blue Number (74.4 mg/g). The best conditions for obtaining activated carbon were 900 ℃, a CO2 flow rate of 200 ml/min., and a 120 minutes holding time. The activated carbon obtained under these conditions had 1094.10 mg/g for Methyl Blue Number, 1078.56 m2 /g for Langmuir surface area, 0.28 m2 /g for macro-pore surface area, 20.45 m2 /g for meso-pore surface area, 783.01 m2 /g for micro-pore surface area, 5.15 ×10-3 ml/g for macro-pore volume, 38.54 ×10-3 ml/g for meso-pore volume, and 343.56 ×10-3 ml/g for micro-pore volume. In addition, based on the relationships established and when the Methyl Blue Number falls between 100 mg/g and 1100 mg/g, the BET surface area, micro pore surface area, and micro pore volume can be estimated from the Methyl Blue Number.
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