*2.2. Reaction Kinetics*

Li et al. [10] have studied and estimated the kinetics of Reactions (1) and (2) in the temperature range of 323.15 K to 353.15 K, as shown by Equations (3) and (4):

$$-r\_{AcAu} = d c\_{AcAu} / dt = k\_{1+} c\_{AcAu} c\_{BuAc} - k\_{1-} c\_{BuAuAc} c\_{HAC} \tag{3}$$

$$r\_{BuAu} = d c\_{BuAu} / dt = k\_{2+} c\_{BuAuAc} c\_{BuAc} - k\_{2-} c\_{BuAu} c\_{HAC} \tag{4}$$

In Equations (3) and (4), *n* is the reaction step; + and − represent forward and backward reaction respectively; *kn*<sup>+</sup>, *kn*− are the reaction rate constants for reaction *n* with unit dm3·mol−1·min−1, which are calculated by Equations (5)–(8):

$$k\_{1+} = 3.29 \times 10^7 e^{(-7115.86/T)} \tag{5}$$

$$k\_{1-} = 1.63 \times 10^{\mathcal{T}} e^{(-6202.74/T)} \tag{6}$$

$$k\_{2+} = 7.93 \times 10^4 e^{(-6009.26/T)} \tag{7}$$

$$k\_{2-} = 7.45 \times 10^5 \varepsilon^{(-6594.28/T)}.\tag{8}$$
