Naoto Tsubouchi, Megumi Nishio, Yuji Shinohara, Javzandolgor Bud, Yuuki Mochizuki
Fuel Processing Technology 176 76 - 84 0378-3820 2018/07/01
[Refereed][Not invited] The optimum conditions for the production of high-surface-area activated carbon from peat were examined in a fixed-bed quartz reactor by using natural soda ash (>
99 mass% Na2CO3) as the activation agent and urea (CH4N2O) as the nitrogen source. In the heating of the peat/urea/Na2CO3 mixture, the surface area of activated carbon significantly increased when the temperature was higher than 700 °C, and it reached 940 and 1100 m2/g at 800 and 900 °C, respectively. When the mixture was also held at 700 and 800 °C for 1 h, the surface area drastically increased from 100 m2/g without holding treatment to 730 m2/g at 700 °C, and it became 1050 m2/g at 800 °C. The effect of the peat/urea/Na2CO3 mixing ratio on the increase in surface area was investigated. The ratio of urea to Na2CO3 was fixed at 1/2 and the proportion of peat was varied in the range of 0.5–2
the surface area was maximum when peat = 1. In another case, the ratio of peat to urea was fixed at 1/1 and the proportion of Na2CO3 was varied in the range of 1–4. In this case, the surface area was maximum (940 m2/g) when Na2CO3 = 2 but decreased when Na2CO3 = 4. On the other hand, when the ratio of peat to Na2CO3 was fixed at 1/2 and the proportion of urea was varied in the range of 0.5–3, the surface area markedly increased up to urea = 1
however, a significant increase did not take place thereafter, even when the proportion of urea was increased. According to these results, the optimum mixing ratio of peat/urea/Na2CO3 and heat treatment conditions to produce high-surface-area activated carbon from peat may be 1/1–3/2 and holding at 800–900 °C for 0–1 h, respectively.