The pyrolysis mechanism of rice straw (RS) was investigated using a tube reactor with Fourier transform infrared (FTIR) spectroscopy and thermogravimetric analyzer. The results show that the maximum pyrolysis rate increases with increasing heating rate and the corresponding temperature also increases. The three-pseudocomponent model could describe the pyrolysis behavior of rice straw accurately. The main pyrolysis gas products are H

2

O

CO

2

CO

CH

4

HCHO(formaldehyde)

HCOOH (formic acid)

CH3OH (methanol)

C

6

H

5

OH (phenol)

etc. The releasing of H

2

O

CO

2

CO and CH

4

mainly focuses at 220-400℃. The H

2

O formation process is separated into two stages corresponding to the evaporation of free water and the formation of primary volatiles. The release of CO

2

first increases with increasing temperature and gets the maximum at 309℃. The releasing behavior of CO is similar to H

2

O and CO

2

between 200 and 400℃. The production of CH

4

happens

compared to CO

2

and CO

at higher temperatures of 275-400℃ with the maximum at 309℃. When the temperature exceeds 200℃

hydroxyl and aliphatic C—H groups decrease significantly

while C—O

olefinic C—C bonds and ether structures increase first in the chars and then the aromatic structure develops with rising temperature. Above 500℃

the material becomes increasingly more aromatic and the ether groups decreases with an increase

of temperature. The aromatization process starts at ≈350℃ and continues to higher temperatures.