The activation regeneration of chlorella residue in the biotechnology factory for activated carbon materials

• Main Authors: Chang, Yuan-Ming, 張元銘
• Other Authors: Tsai, Wen-Tien
• Format: Others
• Language: zh-TW
• Published: 2016
• Online Access: http://ndltd.ncl.edu.tw/handle/34163590673205822016

博士 === 國立屏東科技大學 === 生物資源研究所 === 104 === Microalgae contain many nutrients such as protein and lipid, and possess potential advantages of easy cultivation and rapid growth. Therefore, they have become the most valuable precursors for the development of health-care medical foods or products. On the other hand, microalgal residue will be inevitably generated from the manufacturing process of microalgae-derived products at a certain percentage. This biomass residue is currently reused as feed and fertilizers. In the present study, the chlorella-based microalgal residue was tested as a novel precursor for preparing high-surface area activated carbons by the two processes. One was investigated in a thermogravimetric analysis (TGA) system to proceed carbonization and physical activation with flowing N2 and CO2, respectively. Another process is a combined carbonization-chemical activation with flowing N2 gas in a small-scale laboratory pyrolysis furfance. The results showed that the maximal Brunauer–Emmett–Teller (BET) surface area of the resulting activated carbon, which was produced at the first stage up to 500℃ of carbonization temperature under 10 ℃/min of heating rate and the second stage at activation temperature of 950℃ with the residence time of 30 min, were 840 m2/g. On the other hand, the reuslting activated carbon with over 1,900 m2/g of BET surface area was obtained at 700℃ of activation temperature under 10 ℃/min of heating rate and the residence time of 30 min by potassium carbonate with 3 g/g of impregation ratio (60 min of impregation time at 80℃). More significantly, the resulting activated carbons have high nitrogen contents and no traces of toxic elements as compared to commercial activated carbons, which make them to be used as one of food additives.