Acta Phys. -Chim. Sin. ›› 2010, Vol. 26 ›› Issue (08): 2115-2120.doi: 10.3866/PKU.WHXB20100832

• CHEMICAL KINETICS AND MOLECULE DYNAMICS • Previous Articles     Next Articles

Oxidation Reaction Kinetics of Abietic Acid and Rosin under Ultraviolet Light Irradiation

LIU Xiong-Min, QIN Rong-Xiu, HUANG Pin-Xian, LIU Jia-Ling, MA Li, LI Wei-Guang   

  1. School of Chemistry and Chemical Engineering, Guangxi University, Nanning 530004, P. R. China
  • Received:2010-04-08 Revised:2010-04-19 Published:2010-07-23
  • Contact: LIU Xiong-Min E-mail:xmliu1@gxu.edu.cn
  • Supported by:

    The project was supported by the National Key Technology R & D Program of China (2007BAD82B01) and Science Foundation of Guangxi, China (0639001, 0832002).

Abstract:

We designed an oxidation reactor for abietic acid and rosin oxidation under ultraviolet light irradiation. The oxidation process of abietic acid and rosin were determined by UV spectrophotometry and the rate constants (kb) and activation energy (Ea) of the oxidation process were calculated. The kinetic effect of the quantum efficiency (Φ) and the light intensity (I) on the photooxidation reaction were also investigated. The experimental results showed that the photooxidation kinetics of abietic acid and rosin were pseudo first order. The relationship between the natural logarithm of rate constant (lnkb) and the natural logarithm of the light intensity (lnI) is linear. When the reaction temperatures were 20, 25, and 35 ℃, the apparent reaction rate constants of abietic acid were: lnkb=0.9911lnI-8.860, lnkb=0.8786lnI-8.069, and lnkb=0.8364lnI-7.690, respectively. At 20 ℃, the apparent reaction rate constant of rosin was lnkb=1.204lnI-10.49. The initial quantum efficiency of abietic acid is 0.471 and the relationship between the activation energy (Ea) of abietic acid and the natural logarithm of the light intensity (lnI) is also linear: Ea=-7.549lnI+60.02.

Key words: Abietic acid, Rosin, Photo-oxidation, Kinetics, Rate constant

MSC2000: 

  • O643