Table 1 Pyrolysis conditions and chemical properties of the carbonized rice husks

Temp.

(°C)

330

400

600

Time

(min)

15

15

30

pH

(1:10, H₂O)

6.10 ± 0.01

7.10 ± 0.02

11.00 ± 0.01

EC

(dS/m)

11.49 ± 1.62

9.50 ± 0.83

6.59 ± 0.13

SA

(m²/g)

2.55 ± 0.01

6.49 ± 0.02

5.30 ± 0.00

T-C

(%)

42.33 ± 0.84

43.47 ± 0.12

55.50 ± 0.30

T-N

0.40 ± 0.02

0.40 ± 0.05

0.60 ± 0.01

T-H

5.39 ± 0.11

5.32 ± 0.03

2.11 ± 0.03

T-O

34.61 ± 0.59

32.50 ± 1.33

5.88 ± 1.98

H:C ratio

1.52 ± 0.00

1.46 ± 0.00

0.45 ± 0.01

O:C ratio

0.61 ± 0.01

0.56 ± 0.00

0.08 ± 0.02

(O + N):C ratio

0.33 ± 0.00

0.30 ± 0.01

0.05 ± 0.01