Preparation and characterization of carbonaceous adsorbent from Cedar (Cryptomeria japonica D. Don) Bark

雪松（Cryptomeria japonica D. Don）树皮在林业中是一种麻烦的废弃物，因为它需要很长时间才能腐烂。另一方面，活性炭虽然已经得到了广泛的应用，但由于其在不同的原料和制备条件下表现出不同的性能，因此仍然是活跃的研究对象。本研究旨在阐明以杉木皮为原料制备活性炭的适宜条件。(1)首先，研究了雪松皮在惰性气氛中的碳化行为。通过光学显微镜、表面积和孔隙率测量等仪器分析，对杉木皮的加工过程进行了监控，发现了杉木皮纤维结构基本保留的情况。(2)以所得的含碳材料为原料，考察了活性炭在二氧化碳气氛中的活化条件，得到了性能与商品活性炭相当的活性炭。(3)对当地产生的另一种生物质废弃物，即稻草、糠等进行了炭化和活化研究，发现在研究的材料中，雪松皮最适合作为活性炭的原料。(4)以甲烷为探针，采用脉冲色谱法测定了氦载体的传质速度。从雪松皮制备的样品比常规活性炭的速率略高。

Cedar (Cryptomeria japonica D. Don) bark is a troublesome waste matter in the forestry because it takes long time to rot if left on the ground. On the other hand, activated carbons, although they have been widely used already, are still object of active research because they show large variety of performance depending on starting materials and preparation conditions. This work aimed at clarifying the suitable conditions for preparation of activated carbon from Japanese cedar bark.(1)Firstly, the carbonization behavior of cedar bark in inert atmosphere was investigated. The process was monitored by optical microscope, surface area and porosity measurement, and other instrumental analysis, and the condition in which the fibrous structure of the cedar bark was largely retained was found out.(2)Using the carbonaceous material thus obtained as a starting material, the condition of the activation in the carbon dioxide atmosphere was investigated, and an activated carbon having characteristics comparable to commercial ones was obtained.(3)The carbonization and the activation of another biomass waste produced in the local area, i.e. rice straw, chaff, and others, were also studied, and it was found that cedar bark is most suitable for raw material of activated carbon among the materials studied.(4)The mass transfer velocity was evaluated by a pulse chromatography adapting methane as a probe in helium carrier. The sample prepared from cedar bark showed somewhat higher rate than conventional activated carbon.